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1Association of H.pylori infection with gastric carcinoma:a Meta analysis显示文摘AIM: To follow the principles of evidence based medicine to reach the integrated results of these studies.METHODS: Twenty-one papers of case-control studies were selected, including 11 on gastric cancer, 7 on precancerous lesion of stomach and 3 on lymphoma of stomach: Meta analysis was used to sum up the odds ratios (OR) of these studies.RESULTS: H. Pylori vsgastric cancer (intestinal and diffuse type): the odds ratio from the fixed effect model is 3.0016(95% Cl 2.4197-3.7234, P < 0.001 ). H. Pylori vs precancerous lesion of stomach: a random effect model was used to calculate the summary odds ratio and its value is 2.5635 (95% Cl: 1.8477-3.5566, P < 0.01). H. Pylori vs lymphoma of stomach: though the quantity of literature is too small to make Meta analysis, the data of these 3 studies show that lymphoma of stomach is highly associated with H. Pylori infections.CONCLUSION: Since it had been revealed that H. Pylori infection pre-exists in gastric carcinoma and precancerous lesions, the results of Meta analysis present a strong evidence to support the conclusion that H. Pylori infection is a risk factor for gastric carcinoma.Fu-Bo Xue~1 Yong-Yong Xu~1 Yi Wan~1 Bo-Rong Pan~2 Jun Ren~2 Dai-Ming Fan~3 1 Department of Health Statistics,Department of2 Oncology3 Gastroenterology of XiJing Hospital,the Fourth Military Medical University,Xi’an 710032,Shaanxi Province,China 2001World Journal of Gastroenterology2001,7,6:66
2Rosenthal type inequalities for asymptotically almost negatively associated random variables and applications显示文摘In this paper, we establish some Rosenthal type inequalities for maximum partial sums of asymptotically almost negatively associated random variables, which extend the corresponding results for negatively associated random variables. As applications of these inequalities, by employing the notions of residual Cesàro α-integrability and strong residual Cesàro α-integrability, we derive some results on Lp convergence where 1 < p < 2 and complete convergence. In addition, we estimate the rate of convergence in Marcinkiewicz-Zygmund strong law for partial sums of identically distributed random variables.YUAN DeMei AN Jun 2009Science China Mathematics2009,52,9:50
3BMP-6 inhibits microRNA-21 expression in breast cancer through repressing 6EF1 and AP-1显示文摘Jun Du Shuang Yang Di An Fen Hu Wei Yuan Chunli Zhai Tianhui Zhu 2009Cell Research2009,19,4:44
4The vegetation and climate change during Neocene and Early Quaternary in Jiuxi Basin, China显示文摘Sporopollen record in the Laojunmiao Section at Yumen in the Hexi Corridor foreland depression at the northern margin of the Tibetan Plateau revealed that during the period of 13.0―11.15 Ma the ecological environment of the Jiuxi Basin is characterized by steppe vegetation and a semi-moist climate. During 11.16―8.60 Ma prevailed forests of cypress and a still warmer, moister climate; steppe vegetation and dry climate began probably at about 8.6 Ma. Although aridification had been relaxed time and again during 8.40―6.93 Ma (forest-steppe, warm-semi-moist), 6.64―5.67 Ma (open-forest and steppe, warmer-semi-moist) and 5.42―4.96 Ma (steppe, semi-arid), the climate in the region became drier and drier in response to the fre- quent occurrence of aridity during 6.93―6.64 Ma (steppe, semi-arid), 5.67―5.42 Ma (de- sert-steppe, arid), 3.66―3.30 Ma (desert-steppe, arid) and 2.56―2.21 Ma (desert, arid). Perhaps the important findings of our study are the notable expansion of drought-enduring plants during 3.66―3.30 Ma and about 2.56 Ma and the replacement of vegetation by vast arid desert.MA Yuzhen 1 , FANG Xiaomin 1,2 , LI Jijun 1 , WU Fuli 1 & ZHANG Jun 1 1. Key Laboratory of Western China’s Environmental Systems and College of Resources and Environment, Lanzhou University, Lanzhou 730000, China 2. State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi’an 710075, China 2005Science China Earth Sciences2005,48,5:31
5Assessment of duodenogastric reflux by combined continuous intragastric pH and bilirubin monitoring显示文摘AIM: To assess the diagnostic value of a combination of continuous intragastric pH and bilirubin monitoring in the detection of duodenogastric reflux (DGR), and the effects of diet on the bilirubin absorbance.METHODS: 30 healthy volunteers were divided into twogroups: standard diet group (Group 1) 18 cases, free diet group (Group 2) 12 cases. Each subjects were subjected to simultaneous 24 hour intragastric pH and spectrophotometric bilirubin concentration monitoring (Bilitec 2000).RESULTS: There was no difference of preprandial phasebilirubin absorbance between two groups. The absorbanceof postprandial phase was significantly increased in group 2than group 1. There was no difference between preprandialphase and postprandial phase absorbance in group 1.Postprandial phase absorbance was significantly higher ingroup 2. In a comparison of bile reflux with intragastric pHduring night time, there were 4 types of reflux:Simultaneous increase in absorbance and pH in only 19.6%, increase in bilirubin with unchanged pH 33. 3 %, pHincrease with unchanged absorbance 36. 3 %, and bothunchanged in 10. 8 %. Linear regression analysis showed nocorrelation between percertage total time of pH < 4 aridpercentage total time of absortance > 0. 14, r=0.068, P<0.05.CONCLUSION: Because of the dietary effect, highabsorbance fluids or foods should be avoided in detection.Intrsgastric pH and bilirubin monitoring separately predictthe presence of duodenal (and/or pancreatic) reflux and bilereflux. They can not substitute for each other. The detectionof DGR is improved if the two parameters are combinedsimultanoously.Fei Dai Jun Gong Ru Zhang Jin-Yan Luo You-Ling Zhu Xue-Qin Wang,Department of Gastroenterology,Second Hospital of Xi’ an Jiaotong University,Xi’an 710004,Shaanxi Province,China 2002World Journal of Gastroenterology2002,8,2:30
6Compound Danshen injection improves endotoxin-induced microcirculatory disturbance in rat mesentery显示文摘AIM: To investigate the effect of compound Danshen injection on lipopolysaccharide (LPS)-induced rat mesenteric microcirculatory dysfunctions and the underlying possible mechanism by an inverted intravital microscope and high-speed video camera system. METHODS: LPS was continuously infused through the jugular artery of male Wistar rats at the dose of 2 mg/kg per hour. Changes in mesenteric microcirculation,such as diameters of arterioles and venules,velocity of RBCs in venules,leukocyte rolling,adhesion and emigration,free radicals released from post-capillary venules,FITC- albumin leakage and mast cell degranulation,were observed through an inverted intravital microscope assisted with CCD camera and SIT camera. Meanwhile,the expression of adhesion molecules CD11b/CD18 and the production of free radical in neutrophils,and the expression of intercellular adhesion molecule 1 (ICAM-1) in human umbilical vein endothelial cells (HUVECs) were quantified by flow cytometry (FACS) in vitro. RESULTS: The continuous infusion with LPS resulted in a number of responses in microcirculation,including a significant increase in the positive region of venulestained with Monastral blue B,rolling and adhesion of leukocytes,production of oxygen radical in venular wall,albumin efflux and enhanced mast cell degranulation in vivo,all of which,except for the leukocyte rolling,were attenuated by the treatment with compound Danshen injection. Experiments performed in vitro further revealed that the expression of CD11b/CD18 and the production of oxygen free radical in neutrophils,and the expression of ICAM-1 in HUVECs were increased by exposure to LPS,and they were attenuated by compound Danshen injection. CONCLUSION: These results suggest that compound Danshen injection is an efficient drug with multi-targeting potential for improving the microcirculatory disturbance.Jing-Yan Han Yoshinori Horie Soichiro Miura, Yasutada Akiba Jun Guo Dan Li Jing-Yu Fan Yu-Ying Liu Bai-He Hu Li-Hua An Xin Chang Man Xu De-An Guo Kai Sun Ji-Ying Yang Shu-Ping Fang Ming-Ji Xian Masahiro Kizaki Hiroshi Nagata Toshifumi Hibi 2007World Journal of Gastroenterology2007,13,26:26
7Characteristics of one-year observation of VOCs,NOx, and O_3 at an urban site in Wuhan, China显示文摘A continuous online observation of ozone and its precursors(NOx, VOCs) was carried out in central urban Wuhan from September 2016 to August 2017. The concentration levels of ozone,NOx, VOCs and their variations in urban Wuhan were analyzed, as well as effects of VOCs on ozone photochemical generation and the main controlling factors for ozone production. During the observation period, the average concentrations of ozone and NOx in Wuhan was 22.63 and30.14 ppbv, respectively, and the average concentration of VOCs was 32.61 ppbv(42.3% alkanes,13.0% alkenes, 10.0% aromatics, 7.3% acetylene, 9.9% OVOCs, and 10.5% halohydrocarbons).Ozone concentration was higher in spring and summer as compared with autumn and winter,wheras VOCs and NOx concentratios were lower in spring and summer but higher in autumn and winter. Aromatics and alkenes, two of VOCs species, showed the highest contributions to ozone formation potential in Wuhan(35.7% alkenes, 35.4 aromatics, 17.5% alkanes, 8.6% OVOCs,1.6% halogenated hydrocarbons, and 1.4% acetylene). Among all VOCs species, those with the highest contribution were ethylene, m-xylene, toluene, propylene and o-xylene. The contribution of these five compounds to the total ozone formation potential concentration was 43.90%.Ozone-controlling factors in Wuhan changed within one day; during the early morning hours(6:00–9:00), VOCs/NOx was low, and ozone generation followed a VOCs-limited regime.However, during the peak time of ozone concentration(12:00–16:00), the ratio of VOCs/NOx was relatively high, suggesting that ozone generation followed a NOx-limited regime.Yichang Yang Xingang Liu Jun Zheng Qinwen Tan Miao Feng Yu Qu Junling An Nianliang Cheng 2019Journal of Environmental Sciences2019,31,5:26
8Preparation and activity of conjugate of monoclonal antibody HAb18 against hepatoma F( ab′ )_2 fragment and staphylococcal enterotoxin A显示文摘AIM To prepare the conjugate of staphylococcal enterotoxin A (SEA) protein which is a bacterial SAg and the F(ab')2 fragment of mAb HAbl8 against human hepatocellular carcinoma (HCC), and identify its activity in order to use SAg in the targeting therapy of HCC.METHODS MAb HAbl8 was extracted from the abdominal dropsy of Balb/ c mice, and was purified through chromatography column SP-40HR with Fast protein liquid chromatography (FPLC) system. The F(ab')2 fragment of mAb HAb18 was prepared by papainic digestion method. The conjugate of mAb HAb18 F(ab')2fragment and SEA was prepared with chemical conjugating reagent N-succinimidyl-3-( 2-pyridyldithio) propionate (SPDP) and purified through chromatography column Superose 12with FPLC system. The molecular mass and purity of each collected peak were identified with SDS-PAGE assay. The protein content was assayed by Lowry's method. The antibody activity of HAb18 F (ab')2 against HCC in the conjugate was identified by indirect immunocytochemical ABC method, and the activity of SEA in the conjugate to activate peripheral blood mononuclear cells (PBMC) was identified with MTT assay.RESULTS The lgG mAb HAb18 was extracted,and purified successfully. Immunocytochemical staining demonstrated that it reacted with most of HHCC cells of human HCC cell line. There were two peaks in the process of purification of the prepared HAb18 F(ab)2-SEA conjugate. SDS-PAGE assay demonstrated that the molecular mass of the first peak was about 130 ku, and the second peak was the mixture of about 45 ku and a little 100 ku proteins. The immunocytochemical staining was similar in HAb18 F (ab ')2-SEAconjugate and HAb18 F (ab ')2, i.e., thecytoplasm and/or cell membranes of most HHCC cells were positively stained. The MTT assay showed that the optical absorbance (A) value at 490 nm of HAb18 F (ab')2-SEA conjugate was 0.182 ± 0.012, that of negative control was 0.033± 0.009, and there was significant difference between them ( P < 0.05).CONCLUSION SPDP is a good proteinconjugating reagent and can be used in preparing protein conjugate. The conjugate of mAb HAb18F(ab')2 fragment and SEA protein was preparedsuccessfully in present study and can be used in the experimental study of HCC targeting therapy with the conjugate of SAg and anti-HCC mAbs or their fragments.Lian Jun Yang Yan Fang Sui Zhi Nan Chen Department of Pathology, Fourth Military Medical University. Xi’an 710032, Shaanxi Province, China 2001World Journal of Gastroenterology2001,7,2:20
9Zircon U-Pb geochronology of the volcanic rocks from Fanchang-Ningwu volcanic basins in the Lower Yangtze region and its geological implications显示文摘The latest eruptions in two important Mesozoic volcanic basins of Fanchang and Ningwu located in the middle-lower reaches of the Yangtze River formed the bimodal volcanic rocks of the Kedoushan Formation and ultrapotassic volcanic rocks of the Niangniangshan Formation, respectively. The repre-sentative volcanic rocks of the two Formations were selected for LA-ICPMS zircon U-Pb dating. The results indicate that there exist a large amount of magmatic zircons as indicated by high Th/U ratios in these volcanic rocks. The weighted mean age of 21 analyses is 130.7±1.1 Ma for the Kedoushan Formation, and that of 20 analyses is 130.6±1.1 Ma for the Niangniangshan Formation. These U-Pb ages are interpreted to represent the formation times of the volcanic rocks. In combination with other known geochronological data for Mesozoic volcanic rocks from the Lower Yangtze region, it is proposed that the latest volcanic activations in the Jinniu, Luzong, Fanchang and Ningwu volcanic basins probably came to end prior to ca. 128 Ma. There is no significant time interval between the early and later volcanic activities in the Luzong and Ningwu basins, suggesting a short duration of volcanic activities and thus implying the onset of an extensional tectonic setting at about 130 Ma in the Lower Yangtze region. Integrated studies reveal that the Early Cretaceous magmatic activities and their geochronological framework in the Lower Yangtze region are a response to progressively dynamic deep processes that started with the transformation of tectonic setting from compression to extension, followed by delaminating of the lower part of the thickened lithosphere, lithospheric thinning, asthenosphere upwelling, and crust-mantle interaction.YAN Jun LIU HaiQuan SONG ChuanZhong XU XiSheng AN YaJun LIU Jia DAI LiQun 2009Chinese Science Bulletin2009,54,16:20
10Studies on mechanism of Sialy Lewis-X antigen in liver metastases of human colorectal carcinoma显示文摘INTRODUCTIONSialyl Lewis-X antigen ,correlated with carcinoma, is a group of carbohydrate antigen containing oligosaccharide expressed of embryonic tisue and glycoproteins on cell surface of embryonic tissue[1].The SLeX antigen located on cell surface is synthesized principally by two enzymes ,al ,3fucosyltransfrease and a2, 3sialyctransferase.In adults ,SLeX antigen is expressed principally on the surfaces of granulocytic cells and some tumor cells .Xiao Wei Li~1 Yan Qing Ding~1 Jun Jie Cai~1 Shao Qing Yang~2 Lian Bing An~3 Dong Fang Qiao~3 ~1Department of Pathology,Nanfang Hospital of the First Military Medical University,Guangzhou 510515,Guangdong Province,China ~2The Northern Hospital of PLA,Shenyang 110015,Liaoning Province,China ~3Department of Electronmicroscopy,First Military Medical University,Guangzhou 510515,Gangdong Province,ChinaDr.Xiao Wei Li graduated from the First Military Medical University with a MM degree in 1999.Physician in Charge of pathology,having 6 papers published. 2001World Journal of Gastroenterology2001,7,3:19
11Clinical outcomes of EGFR-TKI treatment and genetic heterogeneity in lung adenocarcinoma patients with EGFR mutations on exons 19 and 21显示文摘Background:Epidermal growth factor receptor(EGFR) mutations,including a known exon 19 deletion(19 del) and exon 21 L858 R point mutation(L858R mutation),are strong predictors of the response to EGFR tyrosine kinase inhibitor(EGFR-TKI) treatment in lung adenocarcinoma.However,whether patients carrying EGFR 19 del and L858 R mutations exhibit different responsiveness to EGFR-TKls and what are the potential mechanism for this difference remain controversial.This study aimed to investigate the clinical outcomes of EGFR-TKI treatment in patients with EGFR 19 del and L858 R mutations and explore the genetic heterogeneity of tumors with the two mutation subtypes.Methods:Of 1127 patients with advanced lung adenocarcinoma harboring EGFR 19 del or L858 R mutations,532 received EGFR-TKI treatment and were included in this study.EGFR 19 del and L858 R mutations were detected by using denaturing high-performance liquid chromatography(DHPLC).T790 M mutation,which is a common resistant mutation on exon 20 of EGFR,was detected by amplification refractory mutation system(ARMS).Next-generation sequencing(NGS) was used to explore the genetic heterogeneity of tumors with EGFR 19 del and L858 R mutations.Results:Of the 532 patients,319(60.0%) had EGFR 19 del,and 213(40.0%) had L858 R mutations.The patients with EGFR 19 del presented a significantly higher overall response rate(ORR) for EGFR-TKI treatment(55.2%vs.43.7%,P = 0.017) and had a longer progression-free survival(PFS) after first-line EGFR-TKI treatment(14.4 vs.11.4 months,P = 0.034) compared with those with L858 R mutations.However,no statistically significant difference in overall survival(OS) was observed between the two groups of patients.T790 M mutation status was analyzed in 88 patients before EGFR-TKI treatment and 134 after EGFR-TKI treatment,and there was no significant difference in the co-existence of T790 M mutation with EGFR 19 del and L858 R mutations before EGFR-TKI treatment(5.6%vs.8.8%,P = 0.554)or after treatment(24.4%vs.35.4%,P = 0.176).In addition,24 patients with EGFR 19 del and 19 with L858 R mutations were analyzed by NGS,and no significant difference in the presence of multiple somatic mutations was observed between the two genotypes.Conclusions:Patients with EGFR 19 del exhibit longer PFS and higher ORR compared with those with L858 R mutations.Whether the heterogeneity of tumors with EGFR 19 del and L858 R mutations contribute to a therapeutic response difference needs further investigation.Jiang-Yong Yu Si-Fan Yu Shu-Hang Wang Hua Bai Jun Zhao Tong-Tong An Jian-Chun Duan Jie Wang 2016Chinese Journal of Cancer2016,35,4:19
12Pathogenesis of acute lung injury in rats with severe acute pancreatitis显示文摘BACKGROUND: Acute lung injury (ALI) is the most common and severe complication of severe acute pancreatitis (SAP). The elucidation of the mechanism of ALI contributes to the diagnosis and treatment of the illness. In this study, we studied the pathogenesis of ALI in rats with severe acute pancreatitis. METHODS: The rats were sacrificed at 1, 3, 5, 6, 9 and 12 hours after the establishment of the model of SAP. Pancreas and lung tissues were obtained for pathological study, and examination of microvascular permeability and myeloperoxidase (MPO) examination. The gene expressions of tumor necrosis factor-α (TNF-α) and intercellular adhesion molecule-1 (ICAM-1) in the pancreas and lung tissues were detected by reverse transcriptase-polymerase chain reaction (RT-PCR). RESULTS: After the establishment of the SAP model, the degree of pancreatic and lung injury increased gradually along with the gradual increase of MPO activity and micro-vascular permeability. Gene expressions of TNF-α and ICAM-1 in the pancreas rose at 1 hour and peaked at 7 hours. In contrast, their gene expression in the lungs rose slightly at 1 hour and peaked at 9-12 hours. CONCLUSION: An obvious time window existed between SAP and lung injury, which is beneficial to the early prevention of the development of ALI.Xue-Min Liu, Jun Xu and Zi-Fa Wang Department of Hepatobiliary Surgery, First Hospital, Xi’an Jiaotong University, Xi’an 710061 , China 2005Hepatobiliary & Pancreatic Diseases International2005,4,4:18
13Comparison of membrane fouling during short-term filtration of aerobic granular sludge and activated sludge显示文摘氧气的小粒的污泥被栽培采用定序批空运反应堆的内部传播。关于短期的膜在氧气的小粒的污泥系统和活性污泥系统之间犯规的对比的实验被调查。膜肮脏蚂蚁被 Fourier 变换也描绘红外线(FTIR ) 光谱学技术。结果证明氧气的小粒的污泥有优秀脱氮能力;TN 的移动效率能到达 90% 。氧气的小粒的污泥能减轻有效地犯规的膜。氧气的小粒的污泥的稳定的膜流动是两次像活性污泥系统的一样。另外,氧气的小粒的污泥能导致严重的膜,这被发现堵住毛孔然而,活性污泥能引起犯规的严重蛋糕。肮脏蚂蚁的主要部件作为蛋白质和多糖材料包括被识别。ZHOU Jun YANG Feng-lin MENG Fan-gang AN Peng WANG Di 2007Journal of Environmental Sciences2007,19,11:18
14Effect of notoginsenoside R1 on hepatic microcirculation disturbance induced by gut ischemia and reperfusion显示文摘AIM: To assess the effect of notoginsenoside R1 on hepatic microcirculatory disturbance induced by gut ischemia/reperfusion (I/R) in mice.METHODS: The superior mesenteric artery (SMA) of C57/BL mice was ligated for 15 min to induce gut ischemia followed by 30-min reperfusion. In another set of experiments, R1 was continuously infused (10 mg/kg per hour) from 10 min before I/R until the end of the investigation to study the influence of R1 on hepatic microcirculatory disturbance induced by gut I/R. Hepatic microcirculation was observed by inverted microscopy, and the vascular diameter, red blood cell (RBC) velocity and sinusoid perfusion were estimated. Leukocyte rolling and adhesion were observed under a laser confocal microscope. Thirty and 60 min after reperfusion, lactate dehydrogenase (LDH), alanine aminotransferase (ALT) and aspartate transaminase (AST) in peripheral blood were determined. The expression of adhesion molecules CD11b/CD18 in neutrophils and tumor necrosis factor-alpha (TNF-α), interleukin-6 (IL-6) and monocyte chemotactic protein-1 (MCP-1) in plasma were evaluated by flow cytometry. E-selectin and intercellular adhesion molecule-1 (ICAM-1) in hepatic tissue were examined by immunofluorescence. RESULTS: After gut I/R, the diameters of terminal portal venules and central veins, RBC velocity and the number of perfused sinusoids were decreased, while the leukocyte rolling and adhesion, the expression of E-selectin in hepatic vessels and CD18 in neutrophils, IL-6, MCP-1, LDH, ALT and AST were increased. R1 treatment attenuated these alterations except for IL-6 and MCP-1.CONCLUSION: R1 prevents I/R-induced hepatic microcirculation disturbance and hepatocyte injury. The effect of R1 is related to its inhibition of leukocyte rolling and adhesion by inhibiting the expression of E-selectin in endothelium and CD18 in neutrophils.Wei-Xing Chen Fang Wang, Yu-Ying Liu, Qing-Jiang Zeng, Kai Sun, Xin Xue, Xiang Li, Ji-Ying Yang, Li-Hua An,Bai-He Hu, Jin-Hui Yang, Chuan-She Wang, Zhi-Xin Li, Lian-Yi Liu, Yan Li, Jun Zheng, Fu-Long Liao, Dong Han,Jing-Yu Fan, Jing-Yan Han Fang Wang Yu-Ying Liu Qing-Jiang Zeng Kai Sun Xin Xue Xiang Li Ji-Ying Yang Li-Hua An Bai-He Hu Jin-Hui Yang Chuan-She Wang Zhi-Xin Li Lian-Yi Liu Yan Li Jun Zheng Fu-Long Liao Dong Han Jing-Yu Fan Jing-Yan Han 2008World Journal of Gastroenterology2008,14,1:17
15An efficient method to synthesize HMX by nitrolysis of DPT with N_2O_5 and a novel ionic liquid显示文摘A novel polyethylene glycol(PEG)-200-based dicationic acidic ionic liquid(PEG_(200)-DAIL) was used to synthesize HMX from DPT by nitrolysis with N_2O_5.It was found that either N_2O_5 or PEG_(200)-DAIL could improve the yield.Furthermore,the combined use of PEG_(200)-DAIL and N_2O_5 could increase the yield of HMX to 64%with the used quantity of HNO_3 decreased dramatically.Hui Zhen Zhi Jun Luo Guang An Feng Chun Xu Lv 2009Chinese Chemical Letters2009,20,4:15
16MHD Flow Control of Oblique Shock Waves Around Ramps in Low-temperature Supersonic Flows显示文摘This article is devoted to experimental study on the control of the oblique shock wave around the ramp in a low-temperature supersonic flow by means of the magnetohydrodynamic(MHD) flow control technique.The purpose of the experiments is to take advantage of MHD interaction to weaken the oblique shock wave strength by changing the boundary flow characteristics around the ramp.Plasma columns are generated by pulsed direct current(DC) discharge,the magnetic fields are generated by Nd-Fe-B rare-earth permanent magnets and the oblique shock waves in supersonic flow are generated by the ramp.The Lorentz body force effect of MHD interaction on the plasma-induced airflow velocity is verified through particle image velocimetry(PIV) measurements.The experimental results from the supersonic wind tunnel indicate that the MHD flow control can drastically change the flow characteristics of the airflow around the ramp and decrease the ratio of the Pitot pressure after shock wave to that before it by up to 19.66%,which leads to the decline in oblique shock wave strength.The oblique shock waves in front of the ramp move upstream by the action of the Lorentz body force.The discharge characteristics are analyzed and the MHD interaction time and consumed energy are determined with the help of the pulsed DC discharge images.The interaction parameter corresponding to the boundary layer velocity can reach 1.3 from the momentum conservation equation.The velocity of the plasma column in the magnetic field is much faster than that in the absence of magnetic field force.The plasma can strike the neutral gas molecules to transfer momentum and accelerate the flow around the ramp.Su Changbing,Li Yinghong,Cheng Bangqin,Wang Jian,Cao Jun,Li Yiwen Engineering College,Air Force Engineering University,Xi’an 710038,China 2010Chinese Journal of Aeronautics2010,23,1:15
17Hollow-in-hollow carbon spheres with hollow foam-like cores for lithium-sulfur batteries显示文摘Jun Zang Taihua An Yajie Dong Xiaoliang Fang Mingsen Zheng Quanfeng Dong Nanfeng Zheng 2015Nano Research2015,8,8:15
18Characterization of Nestin-positive stem Leydig cells as a potential source for the treatment of testicular Leydig cell dysfunction显示文摘Mei Hua Jiang Bing Cai Ying Tuo Jiancheng Wang Zhi Jun Zang Xiang'an Tu Yong Gao Zhijian Su Weiqiang Li Guilan Li Min Zhang Jianwei Jiao Zi Wan Chunhua Deng Bruce T Lahn Andy Peng Xiang 2014Cell Research2014,24,12:14
19Growth induction of hepatic stimulator substance in hepatocytes through its regulation on EGF receptors显示文摘The cytosolic liver-specific growth factor-hepatic stimulator substance (HSS) has been shown to be able to amplify the rat hepatocyte proliferation responded to EGF. In order to get more insight into the mechanism, the regulatory effect of HSS on EGF-receptor(EGF-R) and the receptor phosphorylation at molecular level was studied. HSS partially purified from weanling rat liver was given to cultured hepatocytes and its influence on EGF-R specific binding and internalization as well as mRNA expression were investigated. The results showed that preincubation of hepatocytes with HSS could lead to an increase in [125I]-EGF binding to its receptors and inhibit EGFinduced receptor down-regulation. Furthermore, the overexpression of EGF-R mRNA stimulated by HSS was seen during 2-12 h after the incubation. Additionally, it was demonstrated with human hepatoma sMMC-7721 cells in Western blot that the EGF-R expression and the receptor autophosphorylation were increased with dose/timedependency after HSS treatment. These results strongly suggest that the mechanism of HSS action on hepatocyte growth might be related to its modulation on EGF-R and receptor-mediated signaling transduction.AN WEI XIAO JUN LIU TIAN GUANG LEI JIE DAI GUO GUANG DU(Department of Cell Biology, Capital University of Medical Sciences, Beijing 100054, China) 1999Cell Research1999,9,1:13
20COVID-19: Challenges to GIS with Big Data显示文摘The outbreak of the 2019 novel coronavirus disease(COVID-19)has caused more than 100,000 people infected and thousands of deaths.Currently,the number of infections and deaths is still increasing rapidly.COVID-19 seriously threatens human health,production,life,social functioning and international relations.In the fight against COVID-19,Geographic Information Systems(GIS)and big data technologies have played an important role in many aspects,including the rapid aggregation of multi-source big data,rapid visualization of epidemic information,spatial tracking of confirmed cases,prediction of regional transmission,spatial segmentation of the epidemic risk and prevention level,balancing and management of the supply and demand of material resources,and socialemotional guidance and panic elimination,which provided solid spatial information support for decision-making,measures formulation,and effectiveness assessment of COVID-19 prevention and control.GIS has developed and matured relatively quickly and has a complete technological route for data preparation,platform construction,model construction,and map production.However,for the struggle against the widespread epidemic,the main challenge is finding strategies to adjust traditional technical methods and improve speed and accuracy of information provision for social management.At the data level,in the era of big data,data no longer come mainly from the government but are gathered from more diverse enterprises.As a result,the use of GIS faces difficulties in data acquisition and the integration of heterogeneous data,which requires governments,businesses,and academic institutions to jointly promote the formulation of relevant policies.At the technical level,spatial analysis methods for big data are in the ascendancy.Currently and for a long time in the future,the development of GIS should be strengthened to form a data-driven system for rapid knowledge acquisition,which signifies ts that GIS should be used to reinforce the social operation parameterization of models and methods,especially when providing support for social management.Chenghu Zhou Fenzhen Su Tao Pei An Zhang Yunyan Du Bin Luo Zhidong Cao Juanle Wang Wen Yuan Yunqiang Zhu Ci Song Jie Chen Jun Xu Fujia Li Ting Ma Lili Jiang Fengqin Yan Jiawei Yi Yunfeng Hu Yilan Liao Han Xiao 2020Geography and Sustainability2020,1,1:13
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