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284篇 您的检索式:作者名="Qun ZHAO"
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1Analysis of in vivo patterns of caspase 3 gene expression in primary hepatocellular carcinoma and its relationship to p21^(WAF1) expression and hepatic apoptosis显示文摘AIM To detect the expression of caspase 3gene in primary human hepatocellular carcinoma(HCC)and investigate its relationship to p21WAF1gene expression and HCC apoptosis.METHODS In situ hybridization was employedto determine caspase 3 and p21WAF1expression inHCC.In situ end-labeling was used to detecthepatocytic apoptosis in HCC.RESULTS Twenty-one of 39(53.8%)cases ofHCC were found to express caspase 3transcripts,while 45.2% of HCC failed toexpress caspase 3.Non-cancerous adjacent livertissues showed more positive caspase 3(87.5%,7/8)as compared with HCC(P<0.05).The expression of caspase 3 is correlated withHCC differentiation,72.2%(13/18)ofmoderately to highly differentiated HCC showedcaspase 3 transcripts positive,while only 38.1%of poorly differentiated HCC harbored caspase 3transcripts(P<0.05).No relationship wasfound between caspase 3 expression and tumorsize or grade or metastasis,although 52.5%(5/8)of HCC with metastasis were caspase 3positive and a little higher than that with nometastasis(51.6%,P>0.05).Expression of caspase 3 alone did not affect the apoptosisindex(AI)of HCC.The AI was 7.12%o in caspase3-positive tumors(n=21),while in caspase 3-negative cases(n=18)6.59%0(P>0.05).Expression of caspase 3 clearly segregated withp21WAF1positive tumors as compared withp21WAF1-negative cases(16 of 23,69.6% versus5 of 16,31.3%)with statistical significance(P=0.017).In the cases with positive caspase 3and negative p21WAF1,the Al was found slightlyhigher,but with no statistical significance,thanthat with expression of p21WAF1and caspase 3(7.21‰ vs 6.98‰,P>0.05).CONCLUSION Loss of caspase 3 expressionmay contribute to HCC carcinogenesis,althoughthe expression of caspase 3 does not correlatewell with cell apoptosis in HCC.p21WAF1may bemerely one of the inhibitors which can reducecaspase 3 mediated cell apoptosis in HCCs.Bao Hua Sun Jun Zhang Bao JǜWang Xi Ping Zhao You Kun Wang Zhi Qun Yu Dong Liang Yang Lian Jie Hao Department of Clinical Immunology,Tongji Hospital,Tongji Medical University,Wuhan 430030,Hubei Province,China 2000World Journal of Gastroenterology2000,6,3:65
2Coalbed methane genesis, occurrence and accumulation in China显示文摘Coalbed methane (CBM) is an important type of unconventional gas. Commercial development of CBM in America has been very successful since the 1980s. The CBM industry in Australia and Canada has developed rapidly during the last decade. Commercial development of CBM in China started in the 1990s, and has made great progress. The geological theory of CBM in China has achieved great advancement in genesis, occurrence and accumulation. On the aspect of CBM genesis, five CBM genetic types (primary biogenic gas, secondary biogenic gas, thermal degradation gas, pyrolysis gas and mixed gas) are identified by studying the geochemical characteristics of CBM, and a tracing indicator system is established. The discovery of secondary biogenic gas in medium-high rank coal reservoirs has widened the potential of CBM resources. On the aspect of CBM occurrence, the gas adsorption regulation under combined action of temperature and pressure is revealed by conducting adsorption experiments of different coal ranks under varying temperature and pressure conditions. Besides, by applying the adsorption potential theory in CBM research, the adsorption model under combined action of temperature and pressure is established. The new model can predict CBM resources accurately, and overcome the limitation of the traditional Langmuir model which uses just a single factor to describe the adsorption characteristics of deep buried coal. On the aspect of CBM accumulation, it is proposed that there are three evolutionary stages during CBM accumulation, including gas generation and adsorption, unsaturated gas adsorption, gas desorption-diffusion and preservation. Controlled by tectonic evolution, hydrodynamics and sealing conditions, CBM tends to be regionally enriched in synclines. Advances in geological theory of CBM in China can not only improve understanding of natural gas, but also provide new ideas for further exploration of CBM.Song Yan Liu Shaobo Zhang Qun Tao Mingxin Zhao Mengjun Hong Feng 2012Petroleum Science2012,9,3:29
3Cardiotoxicity of 5-fluorouracil and capecitabine in Chinese patients: a prospective study显示文摘Background:5-Fluorouracil(5-FU)and capecitabine-associated cardiotoxicity ranging from asymptomatic electro-cardiography(ECG)abnormalities to severe myocardial infarction has been reported in a number of studies,but such cardiotoxicity in Chinese patients with malignant diseases has not been investigated to date.In the present study,we aimed to prospectively evaluate the incidence rates and clinical manifestations of 5-FU-and capecitabine-associated cardiotoxicity in cancer patients recruited from multiple centers in China.Methods:Among the 527 patients who completed the study,196 received 5-FU-based chemotherapy and 331 received capecitabine-based chemotherapy as either first-line or adjuvant therapy.Adverse events were reported during the treatment and up to 28 days of follow-up.Outcome measures included ECG,myocardial enzymes,cardiac troponin,brain natriuretic peptide and echocardiography.Univariate analysis and logistic regression were performed for subgroup analysis and identification of significant independent variables that are associated with cardiotoxicity of both agents.Results:In total,161 of 527 patients(30.6%)experienced cardiotoxicity.The incidence rate of cardiotoxicity was 33.8%(112/331)in the capecitabine group,which was significantly higher than the rate of 25%(49/196)in the 5-FU group(P=0.0042).110/527 patients(20.9%)suffered arrhythmia,105/527(19.9%)developed ischemic changes,while only 20/527 patients(3.8%)presented heart failure and 6/527 patients(1.1%)had myocardial infarction.Pre-existing cardiac disease,hypertension,capecitabine-based chemotherapy and duration of treatment were identified as sig-nificant risk factors associated with cardiotoxicity.The odds ratio were 15.7(prior history of cardiac disease versus no history),1.86(capecitabine versus 5-FU),1.06(5-8 versus 1-4 chemotherapy cycles)and 1.58(hypertension versus no hypertension),respectively.Conclusions:Cardiotoxicity induced by fluoropyrimidines in the Chinese population may be underestimated in clini-cal practice.Close monitoring of patients is recommended,especially for those patients at high risk for cardiotoxicity.Possible risk factors are duration of treatment,capecitabine-based chemotherapy,pre-existing cardiac diseases and hypertension.Trial registration This study was initiated on January 22,2014 and has been retrospectively registered with the registra-tion number ChiCTR1800015434 .Jianjun Peng Chao Dong Chang Wang Weihua Li Hao Yu Min Zhang Qun Zhao Bo Zhu Jun Zhang Wenliang Li Fenghua Wang Qiong Wu Wenhao Zhou Ying Yuan Meng Qiu Gong Chen 2018Cancer Communications2018,38,1:23
4Evaluation of an extracellular matrix-derived acellular biphasic scaffold/cell construct in the repair of a large articular high-load-bearing osteochondral defect in a canine model显示文摘YANG Qiang PENG Jiang LU Shi-bi GUO Quan-yi ZHAO Bin ZHANG Li WANG Ai-yuan XU Weng-jing XIA Qun MA Xin-long HU Yong-cheng XU Bao-shan 2011Chinese Medical Journal2011,,23:15
52D MOF Nanoflake-Assembled Spherical Microstructures for Enhanced Supercapacitor and Electrocatalysis Performances显示文摘Metal–organic frameworks(MOFs) are of great interest as potential electrochemically active materials.However, few studies have been conducted into understanding whether control of the shape and components of MOFs can optimize their electrochemical performances due to the rational realization of their shapes. Component control of MOFs remains a significant challenge. Herein, we demonstrate a solvothermal method to realize nanostructure engineering of 2D nanoflake MOFs. The hollow structures withNi/Co-and Ni-MOF(denoted as Ni/Co-MOF nanoflakes and Ni-MOF nanoflakes) were assembled for their electrochemical performance optimizations in supercapacitors and in the oxygen reduction reaction(ORR). As a result, the Ni/CoMOF nanoflakes exhibited remarkably enhanced performance with a specific capacitance of 530.4 F g^(-1)at 0.5 A g^(-1)in1 M LiO H aqueous solution, much higher than that of NiMOF(306.8 F g^(-1)) and ZIF-67(168.3 F g^(-1)), a good rate capability, and a robust cycling performance with no capacity fading after 2000 cycles. Ni/Co-MOF nanoflakes also showed improved electrocatalytic performance for the ORR compared to Ni-MOF and ZIF-67. The present work highlights the significant role of tuning 2D nanoflake ensembles of Ni/Co-MOF in accelerating electron and charge transportation for optimizing energy storage and conversion devices.Huicong Xia Jianan Zhang Zhao Yang Shiyu Guo Shihui Guo Qun Xu 2017Nano-Micro Letters2017,9,4:14
6Long Distance Transmission of SARS-CoV-2 from Contaminated Cold Chain Products to Humans——Qingdao City,Shandong Province,China,September 2020显示文摘Summary What is already known about this topic?Though coronavirus disease 2019(COVID-19)has largely been controlled in China,several outbreaks of COVID-19 have occurred from importation of cases or of suspected virus-contaminated products.Though several outbreaks have been traced to severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)isolated on the outer packaging of cold chain products,live virus has not been obtained.Huilai Ma Zhaoguo Wang Xiang Zhao Jun Han Yong Zhang Hong Wang Cao Chen Ji Wang Fachun Jiang Jie Lei Jingdong Song Shaofeng Jiang Shuangli Zhu Huihui Liu Dongyan Wang Yao Meng Naiying Mao Yanhai Wang Zhen Zhu Zhixiao Chen Bingling Wang Qinqin Song Haijun Du Qun Yuan Dong Xia Zhiqiang Xia Peipei Liu Yuchao Wu Zijian Feng Ruqin Gao George F.Gao Wenbo Xu 2021China CDC weekly2021,3,30:13
7Eleven COVID-19 Outbreaks with Local Transmissions Caused by the Imported SARS-CoV-2 Delta VOC-China,July-August,2021显示文摘Starting from December 2019,Wuhan,China,encountered the first outbreak of coronavirus disease 2019(COVID-19)(1-2).The epidemic was successfully suppressed by strict containment so that the number of infected people was reduced to 0 on April 8,2020(3–4).After that,China experienced roughly 3 dozen outbreaks with local transmission caused by imported severe acute respiratory syndrome coronavirus 2(SARS-CoV-2).Lei Zhou Kai Nie Hongting Zhao Xiang Zhao Bixiong Ye Ji Wang Cao Chen Hong Wang Jiangli Di Jinsong Li Chao Li Zhixiao Chen Ruiqi Ren Peihua Niu Hui Chen Tao Chen Yali Wang Lili Li Bingxue Han Ruhan A Si Chen Dan Li Dan Li Chunxia Jin Xin Zhang Jiangmei Liu Chunyu Xu Yecheng Yao Yenan Feng Zhili Li Bike Zhang Yang Song Peter Hao Yanping Zhang Hao Li Qun Li George F.Gao Guoqing Shi Wenbo Xu 2021China CDC weekly2021,3,41:13
8A Nosocomial COVID-19 Outbreak Initiated by an Infected Dockworker at Qingdao City Port-Shandong Province, China, October, 2020显示文摘On October 10,2020,3 cases of coronavirus disease 2019(COVID-19)were detected via routine preadmission nucleic acid screening of inpatients and their visitors at Qingdao Central Hospital.The 3 cases were all related to the Qingdao Chest Hospital.An additional 9 cases were discovered and confirmed through tracing and testing contacts of the 3 initial cases.Viral isolates from all 12 cases were found to have high degrees of genetic homology with the viral isolate from a dockworker at Qingdao Port,referred to as Patient A in this report.A joint investigation team was formed to determine the source of infection and the scale of the outbreak,and to prevent further spread of the virus.Qun Yuan Zengqiang Kou Fachun Jiang Zhongjie Li Lijie Zhang Huihui Liu Xiang Zhao Dianmin Kang Ruqin Gao Jie Lei 2020China CDC weekly2020,2,43:12
9Vehicle Active Steering Control Research Based on Two-DOF Robust Internal Model Control显示文摘Because of vehicle's external disturbances and model uncertainties,robust control algorithms have obtained popularity in vehicle stability control.The robust control usually gives up performance in order to guarantee the robustness of the control algorithm,therefore an improved robust internal model control(IMC) algorithm blending model tracking and internal model control is put forward for active steering system in order to reach high performance of yaw rate tracking with certain robustness.The proposed algorithm inherits the good model tracking ability of the IMC control and guarantees robustness to model uncertainties.In order to separate the design process of model tracking from the robustness design process,the improved 2 degree of freedom(DOF) robust internal model controller structure is given from the standard Youla parameterization.Simulations of double lane change maneuver and those of crosswind disturbances are conducted for evaluating the robust control algorithm,on the basis of a nonlinear vehicle simulation model with a magic tyre model.Results show that the established 2-DOF robust IMC method has better model tracking ability and a guaranteed level of robustness and robust performance,which can enhance the vehicle stability and handling,regardless of variations of the vehicle model parameters and the external crosswind interferences.Contradiction between performance and robustness of active steering control algorithm is solved and higher control performance with certain robustness to model uncertainties is obtained.WU Jian LIU Yahui WANG Fengbo BAO Chunjiang SUN Qun ZHAO Youqun 2016Chinese Journal of Mechanical Engineering2016,29,4:11
10Scalp Avulsion Combined with Unusual Severe Open Craniocerebral Avulsion Injury显示文摘To the Editor:Scalp avulsion is a severe type of scalp injury,which is most often caused when long,braided hair is caught in running wheels.[1,2] However,scalp avulsion combined with an open skull avulsion fracture is extremely rare.Here we report a unique case of scalp avulsion combined with open craniocerebral injury.Jin-Xi Zhao Qun Guo Yong Yuan Wei Xu Ning-Hui Zhao 2015Chinese Medical Journal2015,,20:10
11Subtle trap recognition based on seismic sedimentology- A case study from Shengli Oilfield显示文摘地震沉积科学用地震数据是沉积岩石和外形的学习。然而,经常,沉积身体特征不能被描述份量上由于地震分辨率的限制。高决定倒置抵消这限制并且被用于地震沉积科学在复杂地质的条件下面识别微妙的陷井,从而拓宽地震沉积科学的适用的范围。在这篇论文,基于地震沉积科学,地震控制阶段的非线性的随机的倒置被用来在 Shengli 油矿在 Chezhen 消沉预言 Es3 的沙的集团企业水库。厚度和在几个阶段的沙的集团企业身体的沉积微外形地图被钻介绍,几个微妙的陷井被预言并且验证。Huang Handong Zhang Ruwei Luo Qun Zhao Di Peng Yongmin 2009Applied Geophysics2009,6,2:10
12Surgical strategy for congenital blepharophimosis syndrome显示文摘背景到目前为止,大多数为先天的 blepharophimosis 症候群的外科的技术是二阶段的过程。在这研究,我们调查了一个修改一个阶段过程减少从 2003 ~ 2005 受苦 patients.Methods,我们采用了与先天的 blepharophimosis 症候群在 16 个病人把 blepharoptosis 修正与中间的 canthoplasty 相结合的一种一个阶段技术(10 男性, 6 女性;从 6 ~ 21 变老) 。所有病人有双边的严重 blepharoptosis,蒙古内此赘皮 inversus,和扁平的背 nasi。上面的盖的运动是 0 ~ 3 公里,眼睛裂缝的垂直长度 2 ~ 4 公里,水平长度在眼睛之间的 13 ~ 22 公里,和距离是 35 ~ 39 公里。病人被跟随在上面为到在在所有病人的 operation.Results 以后的 2 年的一一半在手术以后,眼皮的水平长度 25 公里,垂直长度 6 mm.and 在眼睛 35mm 之间的距离。他们的双眼皮的外观是把 blepharoptosis 修正与中间的 canthoplasty 相结合的修改一个阶段技术能完成的 satisfying.Conclusion 为有先天的 blepharophimosis 的病人的有利结果症候群。HUANG Wei-qing QIAO Qun ZHAO Ru WANG Xiao-jun FANG Xue-quan 2007Chinese Medical Journal2007,,16:9
13Soybean AP1 homologs control flowering time and plant height显示文摘Flowering time and plant height are key agronomic traits that directly affect soybean(Glycine max)yield.APETALA1(AP1)functions as a class A gene in the ABCE model for floral organ development,helping to specify carpel,stamen,petal,and sepal identities.There are four AP1 homologs in soybean,all of which are mainly expressed in the shoot apex.Here,we used clustered regularly interspaced short palindromic repeats(CRISPR)–CRISPR-associated protein 9 technology to generate a homozygous quadruple mutant,gmap1,with loss-of-function mutations in all four GmAP1 genes.Under short-day(SD)conditions,the gmap1 quadruple mutant exhibited delayed flowering,changes in flower morphology,and increased node number and internode length,resulting in plants that were taller than the wild type.Conversely,overexpression of GmAP1a resulted in early flowering and reduced plant height compared to the wild type under SD conditions.The gmap1 mutant and the overexpression lines also exhibited altered expression of several genes related to flowering and gibberellic acid metabolism,thereby providing insight into the role of GmAP1 in the regulatory networks controlling flowering time and plant height in soybean.Increased node number is the trait with the most promise for enhancing soybean pod number and grain yield.Therefore,the mutant alleles of the four AP1 homologs described here will be invaluable for molecular breeding of improved soybean yield.Liyu Chen Haiyang Nan Lingping Kong Lin Yue Hui Yang Qingsong Zhao Chao Fang Haiyang Li Qun Cheng Sijia Lu Fanjiang Kong Baohui Liu Lidong Dong 2020Journal of Integrative Plant Biology2020,62,12:9
14Role of Diffusion-weighted and Contrast-enhanced Magnetic Resonance Imaging in Differentiating Activity of Ankylosing Spondylitis显示文摘Ying-Hua Zhao Yan-Yan Cao Qun Zhang Ying-Jie Mei Ji-Jie Xiao Shao-Yong Hu Wei Li Shao-Lin Li 2017Chinese Medical Journal2017,,11:8
15Impact of land use conversion on soil organic carbon stocks in an agro-pastoral ecotone of Inner Mongolia显示文摘Soil organic carbon(SOC) stocks in terrestrial ecosystems vary considerably with land use types. Grassland, forest, and cropland coexist in the agro-pastoral ecotone of Inner Mongolia, China. Using SOC data compiled from literature and field investigations, this study compared SOC stocks and their vertical distributions among three types of ecosystems. The results indicate that grassland had the largest SOC stock, which was 1.5-and 1.8-folds more than stocks in forest and cropland, respectively. Relative to the stock in 0–100 cm depth, grassland held more than 40% of its SOC stock in the upper 20 cm soil layer; forest and cropland both held over 30% of their respective SOC stocks in the upper 20 cm soil layer. SOC stocks in grazed grasslands were remarkably promoted after ≥20 years of grazing exclusion. Conservational cultivation substantially increased the SOC stocks in cropland, especially in the 0–40 cm depth. Stand ages, tree species, and forest types did not have obvious impacts on forest SOC stocks in the study area likely due to the younger stand ages. Our study implies that soil carbon loss should be taken into account during the implementation of ecological projects, such as reclamation and afforestation, in the arid and semi-arid regions of China.ZHAO Wei HU Zhongmin LI Shenggong GUO Qun YANG Hao ZHANG Tonghui 2017Journal of Geographical Sciences2017,27,8:8
16Association of Overlapped and Un-overlapped Comorbidities with COVID-19 Severity and Treatment Outcomes: A Retrospective Cohort Study from Nine Provinces in China显示文摘Objective Several COVID-19 patients have overlapping comorbidities. The independent role of each component contributing to the risk of COVID-19 is unknown, and how some non-cardiometabolic comorbidities affect the risk of COVID-19 remains unclear.Methods A retrospective follow-up design was adopted. A total of 1,160 laboratory-confirmed patients were enrolled from nine provinces in China. Data on comorbidities were obtained from the patients’ medical records. Multivariable logistic regression models were used to estimate the odds ratio(OR) and 95% confidence interval(95% CI) of the associations between comorbidities(cardiometabolic or non-cardiometabolic diseases), clinical severity, and treatment outcomes of COVID-19.Results Overall, 158(13.6%) patients were diagnosed with severe illness and 32(2.7%) had unfavorable outcomes. Hypertension(2.87, 1.30–6.32), type 2 diabetes(T2 DM)(3.57, 2.32–5.49),cardiovascular disease(CVD)(3.78, 1.81–7.89), fatty liver disease(7.53, 1.96–28.96), hyperlipidemia(2.15, 1.26–3.67), other lung diseases(6.00, 3.01–11.96), and electrolyte imbalance(10.40, 3.00–26.10)were independently linked to increased odds of being severely ill. T2 DM(6.07, 2.89–12.75), CVD(8.47,6.03–11.89), and electrolyte imbalance(19.44, 11.47–32.96) were also strong predictors of unfavorable outcomes. Women with comorbidities were more likely to have severe disease on admission(5.46,3.25–9.19), while men with comorbidities were more likely to have unfavorable treatment outcomes(6.58, 1.46–29.64) within two weeks.Conclusion Besides hypertension, diabetes, and CVD, fatty liver disease, hyperlipidemia, other lung diseases, and electrolyte imbalance were independent risk factors for COVID-19 severity and poor treatment outcome. Women with comorbidities were more likely to have severe disease, while men with comorbidities were more likely to have unfavorable treatment outcomes.MA Yan ZHU Dong Shan CHEN Ren Bo SHI Nan Nan LIU Si Hong FAN Yi Pin WU Gui Hui YANG Pu Ye BAI Jiang Feng CHEN Hong CHEN Li Ying FENG Qiao GUO Tuan Mao HOU Yong HU Gui Fen HU Xiao Mei HU Yun Hong HUANG Jin HUANG Qiu Hua HUANG Shao Zhen JI Liang JIN Hai Hao LEI Xiao LI Chun Yan LI Min Qing LI Qun Tang LI Xian Yong LIU Hong De LIU Jin Ping LIU Zhang MA Yu Ting MAO Ya MO Liu Fen NA Hui WANG Jing Wei SONG Fang Li SUN Sheng WANG Dong Ting WANG Ming Xuan WANG Xiao Yan WANG Yin Zhen WANG Yu Dong WU Wei WU Lan Ping XIAO Yan Hua XIE Hai Jun XU Hong Ming XU Shou Fang XUE Rui Xia YANG Chun YANG Kai Jun YUAN Sheng Li ZHANG Gong Qi ZHANG Jin Bo ZHANG Lin Song ZHAO Shu Sen ZHAO Wan Ying ZHENG Kai ZHOU Ying Chun ZHU Jun Teng ZHU Tian Qing ZHANG Hua Min WANG Yan Ping WANG Yong Yan 2020Biomedical and Environmental Sciences2020,33,12:8
17A New Dendrobine-Type Alkaloid from Dendrobium nobile显示文摘A new dendrobine-type alkaloid has been isolated from stems of Dendrobium nobile lindl.. Its structure has been identified on the basis of spectroscopic method.Qun Fang LIU Wei Min ZHAO 2003Chinese Chemical Letters2003,14,3:8
18Transanal surgery for obstructed defecation syndrome: Literature review and a single-center experience显示文摘Obstructed defecation syndrome(ODS) is a functional disorder commonly encountered by colorectal surgeons and gastroenterologists, and greatly affects the quality of life of patients from both societal and psychological aspects. The underlying anatomical and pathophysiological changes of ODS are complex. However, intra-rectal intussusception and rectocele are frequently found in patients with ODS and both are thought to play an important role in the pathogenesis of ODS. With the development of evaluation methods in anorectal physiology laboratories and radiology studies, a great variety of new operative procedures, especially transanal procedures, have been invented to treat ODS. However, no procedure has been proved to be superior to others at present. Each operation has its own merits and defects. Thus, choosing appropriate transanal surgical procedures for the treatment of ODS remains a challenge for all surgeons. This review provides an introduction of the current problems and options for treatment of ODS and a detailed summary of the essential assessments needed for patient evaluation before carrying out transanal surgery. Besides, an overview of the benefits and problems of current transanal surgical procedures for treatment of ODS is summarized in this review. A report of clinical experience of some transanal surgical techniques used in the authors' center is also presented.Wei-Cheng Liu Song-Lin Wan SM Yaseen Xiang-Hai Ren Cui-Ping Tian Zhao Ding Ken-Yan Zheng Yun-Hua Wu Cong-Qing Jiang Qun Qian 2016World Journal of Gastroenterology2016,22,35:8
19Seasonal bioconcentration of heavy metals in Onchidium struma(Gastropoda:Pulmonata)from Chongming Island,the Yangtze Estuary,China显示文摘The seasonal concentration changes of selected heavy metal Cd,Cr,Cu,Fe,Mn,Pb,and Zn in five tissues of marine gastropod Onchidium struma were studied in the Chongming Island,the Yangtze Estuary in April 2007,July 2006,September 2006,and November 2006,respectively.The results demonstrated that the bioconcentration factor of Cu(biomass/water) in all selected tissues was about 104 magnitudes,Fe and Cd were 103,Zn was 102,and Mn,Pb,and Cr were 101.Hepatopancreas was proven to be the dominant storage tissue of Cr,Cu,Mn,and Zn,whereas Fe and Pb were mainly stored in muscle and digenetic gland,and Cd was stored in vitelline gland and albumen gland.Additionally,it was found that Cu,Fe,Mn,and Zn were concentrated significantly by O.struma(whole-body) in summer or autumn,and Cd,Cr,and Pb increased slightly in spring and winter.Furthermore,the bioconcentration of Cr was nearly 2-fold higher and Zn was 1.6-fold higher in the water compared with the Water Quality Standard for Fisheries.With view of excessive amount of Pb,Cd,and Cu according to seafood standard,the consumption of O.struma might have the risk of health hazard.LI Xiaobo JIA Linzhi ZHAO Yunlong WANG Qun CHENG Yongxu 2009Journal of Environmental Sciences2009,21,2:7
20Review of cylinder block/valve plate interface in axial piston pumps: Theoretical models,experimental investigations, and optimal design显示文摘Axial piston pumps have been widely used in aircraft hydraulic systems to supply the system with pressurized fluid. The continuous improvement of the aircraft performance has put forward the demand on aviation piston pumps for high power density, safety, and reliability. The lubricating interfaces in axial piston machines are the key design issue that greatly determines the pump performance and service life. The cylinder block/valve plate interface is one of these critical lubricating interfaces and has received considerable attention from many researchers in the last half century. This study aims to review the state-of-the-art literature on the cylinder block/valve plate interface comprehensively and systematically. First, we introduce various theoretical models developed to investigate the lubrication behaviors of the interface and compare them in terms of their assumptions and limitations. Second, the experimental studies on the cylinder block/valve plate interface are presented comprehensively, where the involved test rigs are divided into three types according to their fidelity levels and measurement functionality. Third, we summarize some typical approaches of structure optimization, surface shaping, and surface strengthening, which help improve the load-carrying and anti-wear capacities of the interface under severe operating conditions. Finally, the challenges and future trends of the cylinder block/valve plate interface research are discussed briefly.Jiang'ao ZHAO Yongling FU Jiming MA Jian FU Qun CHAO Yan WANG 2021Chinese Journal of Aeronautics2021,34,1:7
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