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1Fluxes of CO_2, N_2O and CH_4 from a typical temperate grassland in Inner Mongolia and its daily variation显示文摘Using a dark enclosed chamber technique, the fluxes of CO2, N2O and CH4 from nature and disturbed grassland were measured on the spot in Inner Mongolian Temperate Grassland along the annual rainfall gradient section ranging from 450 to 200 mm. The results showed that the measured mean fluxes of CO2, N2O and CH4were (1 180.4 ±308.7), (0.010 ± 0.004) and (-0.039 ± 0.016) mg · m-2/h, respectively. The decrease of the fluxes of CO2, N2O and CH4 follows with that of annual rainfall gradient in the measurement area. Human activities, such as grazing and reclamation are also critical factors to affect the fluxes of these gases from grassland. Daily continuous measurement of CO2, N2O and CH4 fluxes showed a strong diurnal variation with higher emission in the daytime. A good relationship between the fluxes of CO2, N2O, CH4 and temperature was exposed in this study.DONG Yunshe, ZHANG Shen, Ql Yuchun, CHEN Zuozhong & GENG Yuanbo1. Institute of Geography, Chinese Academy of Sciences, Beijing 100101, China:2, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China Correspondence should be addressed to Dong Yunshe 2000Chinese Science Bulletin2000,45,17:66
2Analysis on the ecological benefits of the stream water conveyance to the dried-up river of the lower reaches of Tarim River,China显示文摘This paper analyzes the monitored data of the 4 times of stream water conveyances to the river section where the stream flow was cut-off, of 9 groundwater-monitoring sections and 18 vegetation plots in the lower reaches of Tarim River. The results show that the groundwater depth in the lower reaches of Tarim River rose from 9.87 m before the conveyances to 7.74 m and 3.79 m after the first and second conveyances, 3.61 and 3.16 m after the 2 phases of the third conveyance, and 2.66 m after the fourth conveyance. The transverse response scope of groundwater level was gradually enlarged along both sides of the channel of conveyances, i.e., from 450 m in width after the first conveyance to 1050 m after the fourth conveyance, but the response degree of groundwater level was reduced with the increase of the distance away from the channel of conveyances. The composition, distribution and growth status of the natural vegetation are directly related to the groundwater depth. The indexes of Simpson’s biodiversity, McIntosh’s evenness and Margalef’s richness, which reflect the change of the quantity of species and the degree of biodiversity, are reduced from 0.70, 0.48 and 0.90 to 0.26, 0.17 and 0.37 re- spectively along with the drawdown of groundwater level from the upper reaches to the lower reaches. After the stream water conveyances, the natural vegetation in the lower reaches is saved and restored along with the rise of groundwater level, the response scope of vegetation is gradually enlarged, i.e., from 200— 250 m in width after the first conveyance to 800 m after the fourth conveyance. However, there is still a great disparity to the objective of protecting the “Green Corridor”in the lower reaches of Tarim River. Thus, it is suggested to convey the stream water in double-channel way, combine the conveyance with water supply in surface scope, or construct the modern pipe-conveyance network systems so as to save the natural vegetation in an intensive way, achieve the efficient water consumption and speed up the restoration and re- generation of the damaged ecosystems in the lower reaches of Tarim River.CHEN Yaning1,ZHANG Xiaolei1,ZHU Xiangmin2,LI Weihong1,ZHANG Yuanming1,XU Hailiang1,ZHANG Hongfeng1 & CHEN Yapeng1 1.Xinjiang Institute of Ecology and Geography,Chinese Academy of Sciences,Urumqi 830011,China 2.Management Beureau od Tarim River Basin,Kurle 831102,China Correspondence should be addressed to Chen Yaning(email: cheyn@ms.xjb.ac.cn) 2004Science China Earth Sciences2004,47,11:58
3SHRIMP ages of detrital zircons from the Changcheng System in the Ming Tombs area,Beijing:Constraints on the protolith nature and maximum depositional age of the Mesoproterozoic cover of the North China Craton显示文摘The Mesoproterozoic Changcheng System is widely distributed in the North China Craton. Determining its time of deposition and sources is important to understand the Precambrian crustal evolution of the North China Craton. This paper suggests age distribution patterns for detrital zircons from clastic sediments of the Changcheng System in the Ming Tombs area, Beijing. Samples of feldspar-bearing sandstone (CHc-2) and pure sandstone (CHc-9) were collected from the Changzhougou Formation, which constitutes the basal part of the Changcheng System. Detrital zircons show an age range from 2.35 to 2.60 Ga. However, sample CHc-9 in the upper Changzhougou Formation also contains some zircons with ages of 1.9-1.8 Ga and 2.3-2.1 Ga. The age patterns lead to the following conclusions: (1) Most of the detrital material came from a source area composed predominantly of ~2.5 Ga continental crust of the North China Craton; (2) 1.9-1.8 Ga reflects the age record of Palaeoproterozoic continent-continent collisional event in the North China Craton; and (3) the oldest age for deposition of the Changcheng System is 1.8 Ga.WAN Yusheng1,2, ZHANG Qiaoda1 & SONG Tianrui1 1. Institute of Geology, Chinese Academy of Geological Sciences, Beijing 100037, China 2. Beijing SHRIMP Laboratory, Beijing 100037, China Correspondence should be addressed to Wan Yusheng (e-mail: wanyusheng@cags.net.cn) 2003Chinese Science Bulletin2003,48,22:60
4Structural pattern of eastern Himalayan syntaxis in Namjagbarwa and its formation process显示文摘The structural pattern of the eastern Himalayan syntaxis in Namjagbarwa consists of two series of structures with different styles. One series compiles the earlier ductile contractional and lateral-slip deformation system, formed by nearly north-south shortening within the syntaxis, left-lateral and right-lateral slipping along its western and eastern boundaries respectively. They were possibly produced by the indentation of the Indian continent into Asian continent after India-Asia collision. The peak deformation-metamorphic ages in these structures are 62-60 Ma, ~23 Ma and ~13 Ma. The other series is composed of ductile-brittle normal faults distributing concentrically and dipping toward the outsides of Namjagbarwa Peak. They were probably the collapse structures caused by rapid uplift in a later time and the beginning ages for the normal faulting are about 7.3-6.3 Ma.ZHANG Jinjiang, Jl Jianqing, ZHONG Dalai, DING Lin & HE Shundong1. Department of Geology, Peking University, Beijing 100871, China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China Correspondence should be addressed to Zhang Jinjiang (email: zhjj@pku.edu.cn) 2004Science China Earth Sciences2004,47,2:34
5Hyaluronic acid fragments evoke Kupffer cells via TLR4 signaling pathway显示文摘Kupffer cells, expressing toll-like receptor 4 (TLR4), play a central role in hepatic ischemia/reperfusion (I/R) injury. Hyaluronic acid (HA) fragments, degradative products of high-molecular-weight HA (HMW-HA), acquire the ability to activate immune cells under inflammatory conditions. Here we inves- tigated whether HA fragments could activate Kupffer cells and analyzed the underlying mechanism. Kupffer cells were isolated from wild-type mice (WT, C3H/HeN) and TLR4 mutant mice (C3H/HeJ) and HA fragments were produced by the methods of enzyme digestion and chromatography. Then Kupffer cells were stimulated by HA fragments or other control stimuli. The activation of Kupffer cells was estimated as the release of pro-inflammatory cytokines. The activation of p38 MAPK pathway of Kupffer cells was checked and blocking experiments were done as well. The results indicated that HA fragments acquired the ability to activate Kupffer cells in vitro, which was TLR4 dependent and not due to contamination of lipopolysaccharide. Experiments of p38 MAPK kinase inhibition by SB-203580 verified p38 MAPK was required in HA fragments induced Kupffer cells activation. This suggests that HA fragments, degradative products of one of the major glycosaminoglycans of the extracellular matrix, play critical roles in Kupffer cell activation mediated by TLR4 signaling pathway, which is, at least partially, de- pendent on p38 MAPK activation.ZHANG JinXiang1, WANG Hui2, XIAO Qing3, LIANG HuiFang4, LI ZhuoYa4, JIANG ChunFang1, WU HeShui5 & ZHENG QiChang5 1 Department of Emergency Surgery, Union Hospital Affiliated to Huazhong University of Science and Technology, Wuhan 430022, China 2 Department of Medical Genetics, Tongji Medical College Affiliated to Huazhong University of Science and Technology, Wuhan 430030, China 3 Department of Ophthalmology, Union Hospital Affiliated to Huazhong University of Science and Technology, Wuhan 430022, China 4 Department of Medical Immunology, Tongji Medical College Affiliated to Huazhong University of Science and Technology, Wuhan 430030, China 5 Department of General Surgery, Union Hospital Affiliated to Huazhong University of Science and Technology, Wuhan 430022, China 2009Science China(Life Sciences)2009,52,2:33
6Ultrasonically activated scalpel versus monopolar electrocautery shovel in laparoscopic total mesorectal excision for rectal cancer显示文摘AIM: To investigate the feasibility and safety of monopolar electrocautery shovel (ES) in laparoscopic total mesorectal excision (TME) with anal sphincter preservation for rectal cancer in order to reduce the cost of the laparoscopic operation, and to compare ES with the ultrasonically activated scalpel (US). METHODS: Forty patients with rectal cancer, who underwent laparoscopic TME with anal sphincter preservation from June 2005 to June 2007, were randomly divided into ultrasonic scalpel group and monopolar ES group, prospectively. White blood cells (WBC) were measured before and after operation, operative time, blood loss, pelvic volume of drainage, time of anal exhaust, visual analogue scales (VAS) and surgery-related complications were recorded. RESULTS: All the operations were successful; no one was converted to open procedure. No significant differences were observed in terms of preoperative and postoperative d 1 and d 3 WBC counts (P = 0.493, P = 0.375, P = 0.559), operation time (P = 0.235), blood loss (P = 0.296), anal exhaust time (P = 0.431), pelvicdrainage volume and VAS in postoperative d 1 (P = 0.431, P = 0.426) and d 3 (P = 0.844, P = 0.617) between ES group and US group. The occurrence of surgery-related complications such as anastomotic leakage and wound infection was the same in the two groups. CONCLUSION: ES is a safe and feasible tool as same as US used in laparoscopic TME with anal sphincter preservation for rectal cancer on the basis of the skillful laparoscopic technique and the complete understanding of laparoscopic pelvic anatomy. Application of ES can not only reduce the operation costs but also benef it the popularization of laparoscopic operation for rectal cancer patients.Bao-Jun Zhou, Wei-Qing Song, Qing-Hui Yan, Jian-Hui Cai, Feng-An Wang, Jin Liu, Guo-Jian Zhang, Guo-Qiang Duan, Zhan-Xue Zhang, Department of Gastrointestinal Surgery, The Second Hospital of Hebei Medical University, Shijiazhuang 050000, Hebei Province, China Author contributions: Zhou BJ, Song WQ, Yan QH, Cai JH, Wang FA, Liu J, Zhang GJ, Duan GQ and Zhang ZX contributed equally to this work Zhou BJ, Song WQ, Yan QH, Cai JH and Wang FA designed the research Zhou BJ, Liu J and Zhang GJ performed the research Duan GQ and Zhang ZX analyzed the data and Zhou BJ, Song WQ and Yan QH wrote the paper. 2008World Journal of Gastroenterology2008,14,25:25
7Quantitative relationships between vegetation and several pollen taxa in surface soil from North China显示文摘According to the vegetation investigation and pollen analysis of surface samples sampled along a precipitation gradient of the Northeast China Transect (NECT), several pollen taxa, including Pinus, Betula, Quercus, Tilia, Acer, Ulmus, Artemisia, Chenopodiaceae, Gramineae and Cyperaceae, were chosen to make the regression and correlation analyses. The results indicated that there exists a close relationship between vegetation and pollen taxa in surface samples. The regression parameters for ten taxa in the forests in the eastern part of NECT were different from those in the steppes in the western part. Pinus, Betula, Artemisia and Chenopodiaceae, which have large slope and y-intercept terms, were over-representative taxa. Acer, Gramineae and Cyperaceae, which have small slope and y-intercept terms, were under-representative taxa. Quercus, Tilia and Ulmus whose slope terms have negative correlation with y-intercept terms were equi-representative taxa. The pollen taxa with large slope or large y-interceptLI Yiyin, ZHANG Xinshi & ZHOU Guangsheng1. Department of Urbon and Environmental Sciences, Peking University, Beijing 100871, China 2. Laboratory of Quantitative Vegetation Ecology, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China 3. School of Urban and Environmental Sciences, Northeast Normal University, Changchun 130024, China Correspondence should be addressed to Li Yiyin 2000Chinese Science Bulletin2000,45,16:24
8Regional patterns of particulate spectral absorption in the Pearl River estuary显示文摘Spectral absorption coefficients of the total particulate, ap(l ), nonalgal particulate, ad(l ), and phyto-plankton pigment, aph(l ), in the Pearl River estuary and its vicinity waters were determined using the quantitative filter technique. The particulate absorption ap(443) ranged from 0.04 to 1.82 m-1, with the corresponding aph(443) ranging from 0.016 to 0.484 m-1. Two typical spectral patterns are found for the total particulate absorption. For the first typi-cal spectral pattern, the total particulate absorption spectra are similar to that of nonalgal particulate, with values of absorption coefficient decreasing with wavelength. In con-trast, for the second spectral pattern the spectral absorptions by total particulate are very similar to that of phytoplankton pigment. The spectral dependency of absorption by nonalgal particulate follows an exponential increase toward short wavelengths, with an average slope of 0.012±0.002 nm-1. The nonalgal absorption and the fraction of the nonalgal particulate absorption to the total particulate absorption exhibit a distinct trend of decreasing with salinity of the sur-face water. Phytoplankton pigment absorption exhibits a clear trend of increasing nonlinearly with chlorophyll a con-centration. The relationships between the phytoplankton pigment absorption and chlorophyll a concentration can be described by power law, with the determination coefficient r2 of 0.82. But only weak relationships between ap(l ) and chlorophyll a concentration are observed, with the determination coefficient r2 of 0.42. The relatively large scatter around ap(443) versus chl-a relationship would be attributed to the effects of loading of the nonalgal particulate absorption. Our analysis indicated that such relationships similar to that for Case Ⅰ waters can be applicable to optically complex Case Ⅱ waters if the effects caused by nonalgal are corrected. The chlorophyll-specific absorption coefficients of phytoplankton pigment are not constant, it increases with decreasing chlorophyll a level. To improve the accuracy of bio-optical algorithms for remote sensing in coastal waters, further investigations on the variations of specific absorption of chlorophyll pigment must be made.CAO Wenxi, YANG Yuezhong, XU Xiaoqiang, HUANG Liangmin & ZHANG Jianlin LED Laboratory, South China Sea Institute of Oceanology, Chinese Academy of Sciences, Guangzhou 510301, China Correspondence should be addressed to Cao Wenxi (e-mail: wxcao@ scsio.ac.cn) 2003Chinese Science Bulletin2003,48,21:24
9Typical basin-fill sequences and basin migration in Yanshan, North China ——Response to Mesozoic tectonic transition显示文摘Basin-fill sequences of Mesozoic typical basins in the Yanshan area, North China may be divided into four phases, reflecting lithosphere tectonic evolution from flexure (T3), flexure with weak rifting (J1+2), tectonic transition (J3), and rifting (K). Except the first phase, the other three phases all start with lava and volcaniclastic rocks, and end with thick coarse clastic rocks and/or conglomerates, showing cyclic basin development rather than simple cyclic rift mechanism and disciplinary basin-stress change from extension to compression in each phase. Prototype basin analysis, based on basin-fill sequences, paleocurrent distribution and depositional systems, shows that single basin-strike and structural-line direction controlling basin development had evidently changed from east-west to northeast in Late Jurassic in the Yanshan area, although basin group still occurred in east-west zonal distribution. Till Early Cretaceous, main structural-line strike controlling basins just turned to northeast by north in the studied area.LI Zhong, LIU Shaofeng, ZHANG Jinfang & WANG Qingchen1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. China University of Geosciences, Beijing 100083, ChinaCorrespondence should be addressed to Li Zhong (email: lizhongd@mail.igcas.ac.cn) 2004Science China Earth Sciences2004,47,2:15
10Quantitative reconstruction of the paleosalinity at Qinghai Lake in the past 900 years显示文摘Based on the function relationship between the shell length of Limnocythere inopinata and the salinity of its living water in Tibetan Plateau lakes, the paleosalinty of Qinghai Lake in the past 900 years was reconstructed through the measurement of the adult body length of Limno-cythere inopinata. Meanwhile, the paleosalinity sequence of Qinghai Lake during the same period was rebuilt by the Sr/Ca ratio of the shell of Eucypris inflata combined with the Sr/Ca ratio of living ostracod valves from the species of ge-nus Eucypris inflata and the host water. The paleosalinity results obtained by two different methods were compared and assessed in this paper. To check the result, it was also contrasted with other historical climatic sequences of this area including tree ring and ice core. It was shown that the paleosalinity sequence rebuilt by adult ostracod body length had high reliability, and the paleosalinity reconstruction method by trace elements of ostracod shells was not suitable for Qinghai Lake. From the reconstructed paleosalinty se-quence of Qinghai Lake, it can be found that low salinity during 1160—1290 AD showed the humid climate condition on the Mediaeval Warm Period in this area, while the high salinity during 1410—1540 AD, 1610—1670 AD and 1770—1850 AD which was corresponding to the three cold pulses of the Little Ice Age with a dry climate condition. And the high salinity in the latest several decades was consistent with re-cent warm and dry trends of the climate in this area. The good consistency of the reconstructed palaeosalinity sequence and the precipitation sequence in this area rebuilt by tree ring proves the reconstruction of past lake salinity is reliable.ZHANG Enlou1,2,SHEN Ji1,WANG Sumin1,YIN Yu1,ZHU Yuxin1 & XIA Weilan1 1.Key Laboratory of Lake Sediment and Environment,Nanjing institute of Geography and Limnology,Chinese Academy of Sciences,Nan-jing 210008,China 2.Graduate School of Chinese Academy of Sciences,Beijing 100039,China Correspondence should be addressed to Zhang Enlou(e-mail:elzhang@ niglas.ac.cn) 2004Chinese Science Bulletin2004,49,7:14
11Functional analysis of the larval serum protein gene promoter from silkworm,Bombyx mori.显示文摘The regulation region of larval serum protein gene, Bombyx mori. (BmLSP), consisting of the first intron, the first exon, the central promoter region and 5′-upstream region, is cloned from genomic DNA from the silkworm va-riety of Suju譓inghu. Using PCR and restriction endonu-clease methods, a series of luciferase reporter plasmids, driven by different length of BmLSP promoters, are con-structed. Via the transient expression system in BmN cells, the effects of the regulation elements and foreign insect hor-mones on the BmLSP promoter activity are investigated. The results demonstrate that the promoter activity of BmLSP is 5.8- or 4.4-fold higher than that of BmLSPs whose first in-tron or the element in 5′-upstream region harboring the homologous sequence with the first intron of light-chain fib-roin gene (EHIF) is deleted, respectively, suggesting that both the first intron and EHIF contain the main positive cis-acting elements. However, the inactive mariner transposable ele-ment (MTE) in 5′-upstream region presents a negative effect. Furthermore, the effects of juvenile hormone analogue (JHA) on the BmLSP promoter activity show a typical dose-dependent manner, that is, low concentration treat-ments increase the BmLSP promoter activity and high con-centration treatments decrease it. Meanwhile, insect ecdy-sone (MH) treatments present no significant effect.TANG Shunming, YI Yongzhu, SHEN Xingjia, ZHANG Zhifang, LI Yiren & HE Jialu Key Laboratory of Silkworm Biotechnology, Ministry of Agriculture, Sericultural Research Institute, Chinese Academy of Agricultural Sci-ences, Zhenjiang 212018, China Correspondence should be addressed to Zhang Zhifang (e-mail: zjsbsri@ public.zj.js.cn) 2003Chinese Science Bulletin2003,48,23:13
12Carbon isotopic variations of Proterozoic carbonates in Jixian, Tianjin, China显示文摘Along the Proterozoic stratigraphic sections of Jixian, Tianjin, the ??13C values of carbonates are mostly negative in the Changchengian (Changcheng System), varying approximately within a range of (0±1)‰ in the Jixianian (Jixian System), and have commonly positive values of (2±2)‰ in the Qingbaikouan (Qingbaikou System). From Chuanlinggou Formation to Dahongyu Formation, i.e. from ca. 1700 Ma to 1600 Ma, the δ13C values of carbonates increase from about -3‰ to 0‰, but oscillate with large excursion in Dahongyu Formation. Two large excursions occur in the Jixianian, one in Yangzhuang Formation and the other in the third submember of Wumishan Formation overlaying. These integrated and continuous records of carbon isotope reflect secular variations of δ13C value in ancient seawater from ca. 1700 Ma to ca. 800 Ma. The increase and subsequent oscillation of seawater δ13C value occurring from the ages of ca. 1700 to ca. 1600 Ma and <1300 Ma may signify two correlative global tectonic events.CHU Xuelei, ZHANG Tonggang, ZHANG Qirui, FENG Lianjun & ZHANG Fusong1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. Key Laboratory for Mineral Resources Research, Chinese Academy of Sciences, Beijing 100029, China Correspondence should be addressed to Chu Xuelei (email: xlchu@mail.c-geos.ac.cn) 2004Science China Earth Sciences2004,47,2:13
13Clinical and endoscopic features of Chinese reflux esophagitis patients显示文摘AIM: To analyze the clinical and endoscopic features of Chinese patients with reflux esophagitis (RE). METHODS: A total of 1405 RE patients were analyzed retrospectively. Data on gender, age, presence/absence of H pylori infection and associated esophageal hiatal hernia were collected. Esophagitis was divided into different grades according to Los Angeles Classification. RESULTS: Of 18823 patients, 1405 were diagnosed as RE. The ratio of male to female patients was 1.75:1 (P < 0.01). The mean age of male and female patients was significantly different (P = 0.01). The peak age at onset of the disease was 40-60 years. According to Los Angeles Classification, there were significant differences in the age of patients with grades A and B compared to patients with grades C and D (P < 0.01). Two hundred and seventy-seven patients were infected with H pylori, the infection rate was low (P < 0.01). Complication of esophageal hiatal hernia was found to be significantly associated with the severity of esophagitis and age in 195 patients (P < 0.01). Esophageal mucosa damages were mainly located at the right esophageal wall. CONCLUSION: The peak age of onset of RE is 40-60 years and higher in males than in females. The mean age of onset of RE is lower in males than in females. The infection rate of H pylori is significantly decreased in patients with esophagitis. Old age and esophageal hiatal hernia are associated with more severe esophagitis. Right esophageal mucosal damage can occur more often in RE patients.Wei Li, Shu-Tian Zhang, Zhong-Lin Yu, Department of Gastroenterology, Beijing Friendship Hospital Affiliated to Capital Medical University Faculty of Gastroenterology, Capital Medical University Beijing Digestive Disease Center, Beijing 100050, China 2008World Journal of Gastroenterology2008,14,12:12
14Transgene inheritance and quality improvement by expressing novel HMW glutenin subunit (HMW-GS) genes in winter wheat显示文摘The expression vector pBPC30, which carries the high molecular weight glutenin subunit (HMW-GS) 1Dx5 and 1Dy10 genes, was transferred into hexaploid winter wheat cv. Jinghua No. 1, Jing411 and Jingdong No. 6 ex-plants of immature embryos and immature inflorescence by particle bombardment. A large number of resistant trans-genic plants were obtained under the selection of herbicide bialaphos or phosphinothricin (PPT). Confirmed transgenic plants of T0 generation showed successful integration of HMW-GS genes and bar gene into the wheat genome. T1 generation of transgenic plants can resist 20150 mg/L PPT. Protein analysis of T2 seed by SDS-PAGE showed that HMW-GS 1Dx5 and 1Dy10 genes were well expressed in offspring seed of transgenic lines by co-expression with or substitution of endogenous 1Dx2 or 1Dy10. In one transgenic line, TG3-74, a new protein band between endogenous pro-tein subunits 7 and 8 (marked as 8*) of glutenin appeared, but endogenous subunit 8 (encoded by 1By8 gene) was ab-sent. Analysis of gluten rheological quality on seed proteins of 102 T3 plants showed that the sedimentation value of 5 transgenic lines (44.249.0 mL) was remarkably improved, 59.6%64.3% higher than that of wild type Jinghua No. 1 and Jingdong No. 6, similar to bread wheat Cheyenne (48.0 mL). Analysis of dough rheological properties of transgenic lines showed that the dough stable time of 5 transgenic lines range from 16 to 30 min, whereas the dough stable time of wild type was only between 37 min. Our research suggests that introducing novel HMW-GS genes into wheat is an effi-cient way to improve its bread-making quality.ZHANG Xiaodong, LIANG Rongqi, CHEN Xqing, YANG Fengping & ZHANG Liquan Beijing Agro-Biotechnology Research Center, Beijing Academy of Ag-ricultural & Forestry Science, Beijing 100089, China Correspondence should be addressed to Zhang Xiaodong (e-mail: zhangxd@public3.bta.net.cn) 2003Chinese Science Bulletin2003,48,8:12
15Over-expression of an Arabi-dopsisd δ-OAT gene enhances salt and drought tolerance in transgenic rice显示文摘d-OAT, ornithine--aminotransferase, is the key enzyme involved in proline biosynthesis. In this study the Arabidopsis d -OAT gene was transferred into rice (Oryza sativa L. ssp japonica cv. Zhongzuo 321), whose successful integration was demonstrated by PCR and Southern blot analysis. The over-expression of the gene in transgenic rice was also confirmed. Biochemical analysis showed that, under salt or drought stress conditions, proline contents in the leaves and roots in transgenic rice plants were 5- to 15-fold of those in non-transgenic controls. Under stress conditions, germinating rate of transgenic lines is higher than that of controls. Although the growth of rice plants tested were more and more retarded with the increasing of NaCl concentration, the transgenic plants grow faster compared to the controls under the same stress condition. Meanwhile, the resistance to KCl and MgSO4 stresses was also found enhanced in trans-genic rice. Furthermore, the over-expression of d -OAT also improved the yield of transgenic plants under stress condi-tions. The average yield per plant of transgenic lines in-creases about 12%—41% more than that of control lines under 0.1 mol/L NaCl stress. These data indicated that the over-expression of d -OAT, with the accumulation of proline, resulted in the enhancement of salt and drought tolerance and an increase of rice yield, which is of significance in agri-culture.WU Liangqi, FAN Zhanmin, GUO Lei, LI Yongqing, ZHANG Wenjing, QU Li-Jia & CHEN Zhangliang The National Laboratory of Protein Engineering and Plant Genetic En-gineering, College of Life Sciences, Peking University, Beijing 100871, China Correspondence should be addressed to Qu Li-Jia (e-mail: qulj@pku. edu.cn) 2003Chinese Science Bulletin2003,48,23:11
16A new prognostic histopathologic classification of nasopharyngeal carcinoma显示文摘Background:The current World Health Organization(WHO) classification of nasopharyngeal carcinoma(NPC) con?veys little prognostic information.This study aimed to propose an NPC histopathologic classification that can poten?tially be used to predict prognosis and treatment response.Methods:We initially developed a histopathologic classification based on the morphologic traits and cell differentia?tion of tumors of 2716 NPC patients who were identified at Sun Yat?sen University Cancer Center(SYSUCC)(training cohort).Then,the proposed classification was applied to 1702 patients(retrospective validation cohort) from hospitals outside SYSUCC and 1613 patients(prospective validation cohort) from SYSUCC.The efficacy of radiochemotherapy and radiotherapy modalities was compared between the proposed subtypes.We used Cox proportional hazards models to estimate hazard ratios(HRs) with 95% confidence intervals(CI) for overall survival(OS).Results:The 5?year OS rates for all NPC patients who were diagnosed with epithelial carcinoma(EC;3708 patients),mixed sarcomatoid?epithelial carcinoma(MSEC;1247 patients),sarcomatoid carcinoma(SC;823 patients),and squamous cell carcinoma(SCC;253 patients) were 79.4%,70.5%,59.6%,and 42.6%,respectively(P < 0.001).In mul?tivariate models,patients with MSEC had a shorter OS than patients with EC(HR = 1.44,95% CI = 1.27–1.62),SC(HR = 2.00,95% CI = 1.76–2.28),or SCC(HR = 4.23,95% CI = 3.34–5.38).Radiochemotherapy significantly improved survival compared with radiotherapy alone for patients with EC(HR 49–0.75),and possibly for those with SCC(HR = 0.67,95% CI = 0.56–0.80),MSEC(HR = 0.58,95% CI = 0..74–1.28).= 0.63;95% CI = 0.40–0.98),but not for patients with SC(HR = 0.97,95% CI = 0Conclusions:The proposed classification offers more information for the prediction of NPC prognosis compared with the WHO classification and might be a valuable tool to guide treatment decisions for subtypes that are associ?ated with a poor prognosis.Hai-Yun Wang Yih-Leong Chang Ka-Fai To Jacqueline S.G.Hwang Hai-Qiang Mai Yan-Fen Feng Ellen T.Chang Chen-Ping Wang Michael Koon Ming Kam Shie-Lee Cheah Ming Lee Li Gao Hui-Zhong Zhang Jie-Hua He Hao Jiang Pei-Qing Ma Xiao-Dong Zhu Liang Zeng Chun-Yan Chen Gang Chen Ma-Yan Huang Sha Fu Qiong Shao An-Jia Han Hai-Gang Li Chun-Kui Shao Pei-Yu Huang Chao-Nan Qian Tai-Xiang Lu Jin-Tian Li Weimin Ye Ingemar Ernberg Ho Keung Ng Joseph T.S.Wee Yi-Xin Zeng Hans-Olov Adami Anthony T.C.Chan Jian-Yong Shao 2016Chinese Journal of Cancer2016,35,6:10
17Mobile Ubiquitous Service Environment显示文摘The Mobile Ubiquitous Service Environment (MUSE),established through the coordination and integration of mobile telecommunications and ubiquitous network,in the pursuit of Always Best Experience (ABE),represents the major development trend for the next generation mobile wireless network. Research on MUSE will involve the integration of the computing model system,service platform system,operating system and terminal structure system,all of which involve exploration and innovation of a new networking structure,its control and management as well as way of measuring. The change in network resources triggers the change in network computing models. To let readers have a basic understanding of MUSE,this lecture introduces it in four sections. This section focuses on the development and demand analysis of the service platform.Zhang Ping,Ji Yang,Feng Zhiyong (Research Center for Wireless New Technology,Beijing University of Posts and Telecommunications,Beijing 100876,China) The Mobile Ubiquitous Service Environment (MUSE),established through the coordination and integration of mobile telecommunications and ubiquitous network,in the pursuit of Always Best Experience (ABE),represents the major development trend for the next generation mobile wireless network. Research on MUSE will involve the integration of the computing model system,service platform system,operating system and terminal structure system,all of which involve exploration and innovation of a new networking structure,its control and management as well as way of measuring. The change in network resources triggers the change in network computing models. To let readers have a basic understanding of MUSE,this lecture introduces it in four sections. This section focuses on the development and demand analysis of the service platform. 2007ZTE Communications2007,5,2:10
18Post-collisional extensional and thrust-nappe structures in northern part of Dabie Mountains显示文摘Thrust-nappe structures and extensional struc-tures simultaneously occur in the northern part of the Dabie Mountains. The systematic structural study reveals that extensional structures along the Mozitan-Xiaotian fault and thrust-nappe structures that take the Jinzhai-Shucheng fault as their frontal thrust share the same shear sense, and display a transitional relationship from the ductile exten- sional structure of deep level in the south to the ductile-brit- tle and brittle thrust-nappe structure of shallow level in the north. The extensional and thrust-nappe structures in the region are explained to result from post-collisional processes by the continuous subduction of the Yangtze continental block and the extension induced by the uplifting of the core part of the Dabie Mountains, which are components of the extensional structures produced in the exhumation process of the ultrahigh pressure metamorphic rocks in the Dabie Mountains. Because of the frontal blocking in the process of the north-westward spreading, the extension and detachment of the low-grade metamorphic rocks along the Mozi-tan-Xiaotian fault was transformed into the northwestward thrusting, resulting in the thrust-nappe structures. They de-veloped in the period of 200 170 Ma, maybe last till the late Jurassic.JIANG Laili, WU Weiping, CHU Dongru, LIU Yican & ZHANG Yong Geological Survey of Anhui Province , Hefei 230001, China Correspondence should be addressed to Jiang Laili (e-mail: lailij@mail. hf.ah.cn) 2003Chinese Science Bulletin2003,48,21:9
19Insulin improves cardiac myocytes contractile function recovery in simulated ischemia-reperfusion:Key role of Akt显示文摘The present study examined cardiac myocytecontractile and Ca2+ transient responses to insulin duringsimulated ischemia/reperfusion (I/R) and furtherinvestigated the role of protein kinase B (Akt) in the insulin-induced inotropic effect. Ventricular myocytes wereenzymatically isolated from adult Sprague-Dawley rats and perfused with Tyrode solution while electrically field-stimulated. Simulated I/R was induced by perfusing the cells with chemical anoxic solution including sodiumcyanide-sodium lactate for 15 min followed by reperfusionwith normal oxygenated Tyrode solution with or withoutinsulin. It is found that insulin only at concentration as high as 10 IU/L could increase cell shortening (16±5%, P < 0.05) in normal myocytes, whereas it concentration-dependently (0.01—10 IU/L) increased the contraction,the velocity ofshortening/releng- thening and Ca2+ transient in I/Rmyocytes. In addition, insulin treatment (1 IU/L) increasedAkt phosphorylation of I/R cardiomyocytes by 2.4-foldcompared with that of the control (P < 0.01). Mostimportantly, pretreatment with LY 294002, a specificinhibitor of phosphatidylinositol 3′-kinase (PI3-kinase), significantly inhibited both Akt phosphorylation and thepositive inotropic response to insulin in the I/Rcardiomyocytes. These results suggest that insulin exertsdirect positive inotropic effect by increasing Ca2+ transient of cardiomyocytes, which is enhanced in the pathologicalcondition of I/R. Akt activation plays an important role inthe insulin-induced improvement of myocyte contractile function following I/R.ZHANG Bo, ZHANG Haifeng, FAN Qian, MA Xinliang & GAO Feng Department of Physiology, The Fourth Military Medical University,Xi抋n 710032, China Correspondence should be addressed to Gao Feng (e-mail: fgao@fmmu.edu.cn) 2003Chinese Science Bulletin2003,48,13:9
20Periodicity and map for discovery of new ionic liquids显示文摘There is virtually no limit in the number of ionic liquids. How to select proper ones or discover new ones with desirable properties in such a large pool of ionic liquids? It has become a bottleneck in the researches and applications of ionic liquids. Mendeleev’s periodic law states that the properties of the elements vary periodically. Whether the similar regularity exists among ionic or mo-lecular fragments of compounds is an interesting topic. In this work, we attempted to establish a pe-riodicity and draw a “map” of ionic liquids for providing definite guidance to discover, design, and se-lect the proper ionic liquids rather than trial-and-error. If a complete regularity of the system of ionic liquids can be finally established in the future, we are near an epoch in understanding the existing differences and the reasons for the similarity of the ions or molecular fragments.ZHANG Suojiang, SUN Ning, ZHANG Xiangping & Lü Xingmei Research Laboratory for Green Chemical Engineering and Technology, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100080, China Correspondence should be addressed to Zhang Suojiang 2006Science China Chemistry2006,49,2:9
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