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452篇 您的检索式:作者名="Li Fang Du"
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1Gallstone recurrence after successful percutaneous cholecystolithotomy:a 10-year follow-up of 439 cases显示文摘BACKGROUND: Stone recurrence is a major problem in the medication of gallstones with gallbladder preservation. The aim of this study was to determine the long-term recurrence rate of gallstones and the clinical outcome after successful percutaneous cholecystolithotomy (PCCL) treatment, and to investigate the possible risk factors for gallstone recurrence. METHODS: After successful PCCL for gallstones, 439 patients were followed up during a 10-year period. The long-term gallstone recurrence rate and clinical outcome were evaluated. Risk factors associated with stone recurrence were identified. RESULTS: Gallstone recurrence was detected in 182 of 439 PCCL patients, giving an overall recurrence rate of 41.46%. The cumulative gallstone recurrence rate for each of the 10 post-operative years was 9.57%, 18.91%, 27.33%, 34.14%, 37.59%, 39.86%, 41.90%, 42.73%, 42.85%, and 43.21%, respectively. Among these recurrent patients, 94 were asymptomatic, 80 suffered from nonspecific upper gastrointestinal symptoms and 8 suffered from abdominal pain or biliary colic. Thirty-eight of the 182 patients were retreated with cholecystectomy. The risk factors for stone recurrence included a family history of gallstones, preference for fatty food, accompanying liver disease, multiple stones and poor gallbladder function pre-PCCL. CONCLUSIONS: In this study, the overall recurrence rate of gallstone was 41.46% during a 10-year period. The highest frequency of gallstone recurrence was during the 5th to 6th postoperative years and then continued to slowly increase. Risk factors for stone recurrence varied.We suggest that the use of PCCL in patients with gallstones should be considered carefully because of stone recurrence.Zou, Yi-Ping Du, Ji-Dong Li, Wei-Min Xiao, Yin-Qi Xu, Hong-Bin Zheng, Fang Huang, Hui Liu, Hao-Run Li, Hu-Cheng 2007Hepatobiliary & Pancreatic Diseases International2007,6,2:43
2MiRNA profile in esophageal squamous cell carcinoma:Downregulation of miR-143 and miR-145显示文摘AIM:To investigate the expression profile of miRNA in esophageal squamous cell carcinoma(ESCC).METHODS:The expression profile of miRNA in ESCC tissues was analyzed by miRNA microarray.The expression levels of miR-143 and miR-145 in 86 ESCC patients were determined by real-time polymerase chain reaction(PCR) using TaqMan assay.The mobility effect was estimated by wound-healing using esophageal carcinoma cells transfected with miRNA expression plasmids.RESULTS:A set of miRNAs was found to be deregulated in the ESCC tissues,and the expression levels of miR-143 and-145 were significantly decreased in most of the ESCC tissues examined.Both miR-143 and miR-145 expression correlated with tumor invasion depth.The transfection of human esophageal carcinoma cells with miR-143 and miR-145 expression plasmids resulted in a greater inhibition of cell mobility,however,the protein level of the previously reported target of miR-145,FSCN1,did not show any significant downregulation.CONCLUSION:These findings suggest that the deregulation of miRNAs plays an important role in the progression of ESCC.Both miR-143 and miR-145 might act as anti-oncomirs common to ESCC.Bing-Li Wu Li-Yan Xu Ze-Peng Du Lian-Di Liao Hai-Feng Zhang Qiao Huang Guo-Qiang Fang En-Min Li 2011World Journal of Gastroenterology2011,17,1:31
3Waist Circumference Reference Values for Screening Cardiovascular Risk Factors in Chinese Children and Adolescents显示文摘Objectives To explore the optimal threshold values of waist circumference(WC)for detecting cardiovascular(CV)risk factors among Chinese children and adolescents.Methods Association of WC with CV risk factors was studied among 65 898 children aged 7-18 years whose data were pooled from nine previous studies in China.CV risk factors in this study included hypertension(blood pressure above 95 percentile levels),dyslipidemia(with one or more of the following three indexes:TG≥1.7 mmol/L,TC≥5.18 mmol/L,and HDL-C≤1.04 mmol/L)and elevated glucose level(fasting plasma glucose ≥5.6 mmol/L).Receive-operating characteristic analysis(ROC)and logistic regression were employed to derive optimal age-and sex-specific waist circumference references for predicting CV risk factors.Results A slight increasing trend of CV risk factors was observed starting from the 75th percentile of waist circumference in the study population,while a remarkable increasing trend occurred from the 90th percentile.The optimal waist circumference thresholds for predicting high blood pressures were at the 75th percentile for both boys and girls,which was at the 90th percentiles for detecting at least two of the above three CV risk factors.In comparison with children with waist circumference below the 75th percentile,the odds ratio of two CV risk factors doubled among children with waist circumference between the 75th and the 90th percentile,and increased by 6 times among children with waist circumference above the 90th percentile.The trend of high blood pressure increasing with waist circumference remained significant after having been stratified by BMI category.Conclusion The 75th and the 90th percentiles of WC are the optimal cut-off points for predicting an increased and a substantially increased risk of CV factors in Chinese children and adolescents,respectively.GUAN-SHENG MA CHENG-YE JI JUN MA JIE MI R1TA YT SLING FENG XIONG WEI-LI YAN XIAO-QI HU YAN-PING LI SONG-M1NG DU HONG-YUN FANG AND J1NG-XIONG JIANG 2010Biomedical and Environmental Sciences2010,23,1:25
4Pharmacokinetics and disposition of anlotinib, an oral tyrosine kinase inhibitor, in experimental animal species显示文摘Chen-chun ZHONG Feng CHEN Jun-ling YANG Wei-wei JIA Li LI Chen CHENG Fei-fei DU Su-ping ZHANG Chengying XIE Na-ting ZHANG Olajide E OLALEYE Feng-qing WANG Fang XU Li-guang LOU Dong-ying CHEN Wei NIU Chuan LI 2018Acta Pharmacologica Sinica2018,39,6:24
5The Chinese Society of Clinical Oncology(CSCO)clinical guidelines for the diagnosis and treatment of nasopharyngeal carcinoma显示文摘Nasopharyngeal carcinoma(NPC)is a malignant epithelial tumor originating in the nasopharynx and has a high incidence in Southeast Asia and North Africa.To develop these comprehensive guidelines for the diagnosis and management of NPC,the Chinese Society of Clinical Oncology(CSCO)arranged a multi-disciplinary team comprising of experts from all sub-specialties of NPC to write,discuss,and revise the guidelines.Based on the findings of evidencebased medicine in China and abroad,domestic experts have iteratively developed these guidelines to provide proper management of NPC.Overall,the guidelines describe the screening,clinical and pathological diagnosis,staging and risk assessment,therapies,and follow-up of NPC,which aim to improve the management of NPC.Ling-Long Tang Yu-Pei Chen Chuan-Ben Chen Ming-Yuan Chen Nian-Yong Chen Xiao-Zhong Chen Xiao-Jing Du Wen-Feng Fang Mei Feng Jin Gao Fei Han Xia He Chao-Su Hu De-sheng Hu Guang-Yuan Hu Hao Jiang Wei Jiang Feng Jin Jin-Yi Lang Jin-Gao Li Shao-Jun Lin Xu Liu Qiu-Fang Liu Lin Ma Hai-Qiang Mai Ji-Yong Qin Liang-Fang Shen Ying Sun Pei-Guo Wang Ren-Sheng Wang Ruo-Zheng Wang Xiao-Shen Wang Ying Wang Hui Wu Yun-Fei Xia Shao-Wen Xiao Kun-Yu Yang Jun-Lin Yi Xiao-Dong Zhu Jun Ma 2021Cancer Communications2021,41,11:22
6Mechanism of action of gypenosides on type 2 diabetes and non-alcoholic fatty liver disease in rats显示文摘AIM:To explore the mechanism of action of gypenosides(GPs)on type 2 diabetes mellitus and non-alcoholic fatty liver disease(T2DM-NAFLD)in rats.METHODS:Sixty rats were randomly divided into a healthy group,an untreated disease model group andGP-treatment groups.The study involved the evaluation of biochemical parameters,including serum aspartate transaminase(AST),alanine transferase(ALT),blood glucose(BG),triglycerides(TG)and total cholesterol(TC).Additionally,the protective effect of the treatments were confirmed histopathologically and the expression of TNF-αand NF-κB in the rat liver was analyzed using immunohistochemistry.The expression of proliferatoractivated receptor gamma(PPARγ)and cytochrome P450(CYP450)1A1 m RNA was determined by quantitative RTPCR.RESULTS:GP treatments at oral doses of 200,400,and800 mg/kg per day significantly decreased the levels of serum AST and ALT(P<0.05,P<0.01),especially at the dose of 800 mg/kg per day.To a similar extent,GP at800 mg/kg per day reduced the levels of BG(4.19±0.47,P<0.01),TG(80.08±10.05,P<0.01),TC(134.38±16.39,P<0.01)and serum insulin(42.01±5.04,P<0.01).The expression of TNF-αand NF-κB measured by immunohistochemistry was significantly reduced by GPs in a dose-dependent manner,and the expression of PPARγand CYP4501A1 m RNA,as measured using quantitative real-time PCR,were significantly down-regulated by GPs.Moreover,GPs decreased the infiltration of liver fats and reversed the histopathological changes in a dosedependent manner.CONCLUSION:This study suggests that GPs have a protective effect against T2DM-NAFLD by down-regulating the expression of TNF-αand NF-κB proteins,and PPARγand CYP4501A1 m RNAs.Qin He Jin-Ke Li Fang Li Ru-Gui Li Guo-Qing Zhan Gang Li Wei-Xing Du Hua-Bing Tan 2015World Journal of Gastroenterology2015,21,7:22
7Intraoperative radiofrequency ablation combined with ^(125)iodine seed implantation for unresectable pancreatic cancer显示文摘AIM: To evaluate the feasibility, efficacy and safety of intraoperative radiofrequency ablation (RFA) combined with 125 iodine seed implantation for unresectable pancreatic cancer. METHODS: Thirty-two patients (21 males and 11 females) at the age of 68 years (range 48-90 years) with unresectable locally advanced pancreatic cancer admitted to our hospital from January 2006 to May 2008 were enrolled in this study. The tumor, 4-12 cm in diameter, located in pancreatic head of 23 patients and in pancreatic body and tail of 9 patients, was found to be unresectable during operation. Diagnosis of pancreatic cancer was made through intraoperative biopsy. Patients were treated with FRA combined with 125 iodine seed implantation. In brief, a RFA needle was placed, which was confirmed by intraoperative ultrasound to decrease the potential injury of surrounding vital structures, a 125 iodine seed was implanted near the blood vessels and around the tumor border followed by bypass palliative procedure (cholangio-jejunostomy and/or gastrojejunostomy) in 29 patients.RESULTS: The serum CA 19-9 level was decreased from 512 ± 86 U/mL before operation to 176 ± 64 U/mL, 108 ± 42 U/mL and 114 ± 48 U/mL, respectively, 1, 3 and 6 mo after operation (P < 0.05). The pain score on day 7 after operation, 1 and 3 mo after combined therapy was decreased from 5.86 ± 1.92 before operation to 2.65 ± 1.04, 1.65 ± 0.88 and 2.03 ± 1.16, respectively, after operation (P < 0.05). The rate of complete response (CR), partial response (PR), stable disease (SD), progressive disease (PD) in 32 patients was 21.8% (7/32), 56.3% (18/32), 15.6% (5/32) and 6.3% (2/32), respectively, 6 mo after operation, with a median overall survival time of 17. 5 mo. The median survival time of patients at stage Ⅲ was longer than that of those at stage Ⅳ (19 mo vs 10 mo, P = 0.0026). The median survival time of patients who received and did not receive chemotherapy after operation was 20 mo and 16 mo, respectively (P = 0.0176). Of the 32 patients, 3 (10.6%) experienced postoperative complications including transient biliary leaks in 2 patients and acute pancreatitis in 1 patient. All the patients recovered well after conservative support treatment. CONCLUSION: Intraoperative RFA combined with 125 iodine seed implantation is a feasible and safe procedure for unresectable pancreatic cancer with acceptable minor complications, and can prolong the survival time of patients, especially those at stage Ⅲ.Yi-Ping Zou Wei-Min Li Fang Zheng Fu-Cheng Li Hui Huang Ji-Dong Du Hao-Run Liu 2010World Journal of Gastroenterology2010,16,40:21
8Climate and litter C/N ratio constrain soil organic carbon accumulation显示文摘Soil organic carbon(SOC) plays critical roles in stabilizing atmospheric CO2 concentration, but the mechanistic controls on the amount and distribution of SOC on global scales are not well understood. In turn, this has hampered the ability to model global C budgets and to find measures to mitigate climate change. Here, based on the data from a large field survey campaign with 2600 plots across China’s forest ecosystems and a global collection of published data from forested land, we find that a low litter carbon-to-nitrogen ratio(C/N) and high wetness index(P/PET, precipitation-to-potentialevapotranspiration ratio) are the two factors that promote SOC accumulation, with only minor contributions of litter quantity and soil texture. The field survey data demonstrated that high plant diversity decreased litter C/N and thus indirectly promoted SOC accumulation by increasing the litter quality. We conclude that any changes in plant-community composition, plant-species richness and environmental factors that can reduce the litter C/N ratio, or climatic changes that increase wetness index, may promote SOC accumulation. The study provides a guideline for modeling the carbon cycle of various ecosystem scales and formulates the principle for land-based actions for mitigating the rising atmospheric CO2 concentration.Guoyi Zhou Shan Xu Philippe Ciais Stefano Manzoni Jingyun Fang Guirui Yu Xuli Tang Ping Zhou Wantong Wang Junhua Yan Gengxu Wang Keping Ma Shenggong Li Sheng Du Shijie Han Youxin Ma Deqiang Zhang Juxiu Liu Shizhong Liu Guowei Chu Qianmei Zhang Yuelin Li Wenjuan Huang Hai Ren Xiankai Lu Xiuzhi Chen 2019National Science Review2019,6,4:21
9Relationship of Body Mass Index, Waist Circumference and Cardiovascular Risk Factors in Chinese Adult显示文摘Objective To compare the relative risk of waist circumference (WC) and/or BMI on cardiovascular risk factors. Methods A cross-sectional data of 41 087 adults (19 567 male and 21 520 female) from the 2002 China National Nutrition and Health Survey were examined. According to the obesity definition of WGOC (BMI, 24 kg/m2 and 28 kg/m2; WC, male 85 cm and 95 cm for male, 80 cm and 90 cm for female), the study population were divided into 9 groups. The prevalence and odds ratio (ORs) of cardiovascular disease (CVD) risk factors (hypertension, high fasting plasma glucose and dyslipidemia) were compared among these 9 groups. Stepwise linear regression analyses were used to compare the likelihood of BMI and/or WC on CVD risk factors. Results Both the indexes levels and the odds ratios of CVD risk factors were significantly increased (decreased for HDL-C levels) along with the increase of WC and/or BMI, even when the effect of age, sex, income, education, sedentary activity and dietary factors were adjusted. The variances (R2) in CVD risk factors explained by WC only and BMI only were quite similar, but a little bit larger when WC and BMI were combined. The standard β was higher of BMI when predicting systolic BP and was higher of WC when predicting TG, TC and HDL. Conclusions BMI and WC had independent effects on CVD risk factors and combination of BMI and WC would be more predictive. Findings from the present study provided substantive evidence for the WGOC recommendation of a combined use of BMI and WC classifications.SONG-MING DU GUAN-SHENG MA YAN-PING LI HONG-YUN FANG XIAO-QI HU XIAO-GUANG YANG YONG-HUA HU 2010Biomedical and Environmental Sciences2010,23,2:18
10A hepatoprotection study of Radix Bupleuri on acetaminophen-induced liver injury based on CYP450 inhibition显示文摘We investigated the potential hepatoprotective effect of Radix Bupleuri(RB) by inducing acute liver injury(ALI) in an animal model using acetaminophen(APAP) after pretreatment with RB aqueous extract for three consecutive days. Compared to those of the APAP group, the biochemical and histological results of the RB pretreatment group showed lower serum aspartate transaminase(AST) and alanine transaminase(ALT) levels as well as less liver damage. Pharmacokinetic study of the toxicity related marker acetaminophen-cysteine(APC) revealed a lower exposure level in rats, suggesting that RB alleviated APAP-induced liver damage by preventing glutathione(GSH) depletion. The results of cocktail approach showed significant inhibition of CYP2 E1 and CYP3 A activity. Further investigation revealed the increasing of CYP2 E1 and CYP3 A protein was significantly inhibited in pretreatment group,while no obvious effect on gene expression was found. Therefore, this study clearly demonstrates that RB exhibited significant protective action against APAP-induced acute live injury via pretreatment, and which is partly through inhibiting the increase of activity and translation of cytochrome P450 enzymes, rather than gene transcription.WANG Yu-Xin DU Yi LIU Xia-Fei YANG Fang-Xiu WU Xiao TAN Li LU Yi-Hong ZHANG Jing-Wei ZHOU Fang WANG Guang-Ji 2019Chinese Journal of Natural Medicines2019,17,7:18
11Report on Childhood Obesity in China (10): Association of Sleep Duration with Obesity显示文摘Objectives To explore the association of sleep duration with obesity among children in urban areas of China.Methods A total of 6 576 children(3 293 boys and 3 283 girls) aged 7-11 years were randomly selected from 36 primary schools in 6 metropolitan cities in China.A 7-day Physical Activity Recall was used to assess the sleep duration and physical activity level.The height,weight,waist circumference(WC) and percentage of body fat(%BF,as determined by bioelectrical impedance analysis technique) were measured by following the standardized operation procedures.The information on demography,lifestyle and eating habits was collected with a self-administered questionnaire from participants and their parents.Results The average sleep duration per night in the children was 9.7 h with the decreasing trends along with the increase of age(P<0.05).The sleep duration was negatively associated with body mass index(BMI) and WC in both boys and girls after adjustment for confounders(β value-0.23 and-0.82 for boys,-0.24 and-0.91 for girls,respectively,P<0.01).However,no significant association of sleep duration with %BF was found.Children who slept less than 9.0 h per night had a higher risk for overweight and obesity(OR=1.29,95% CI:1.01,1.64) and abdominal obesity(OR=1.38,95% CI:1.04,1.83) as compared with those who slept for 10.0-10.9 h.Conclusions Short sleep duration is associated with obesity.It is important to ensure adequate sleep duration of children and foster their healthy lifestyle at an early stage of life.MENG Li Ping LIUAi Ling HU Xiao Qi ZHANG Qian DU Song Ming FANG Hong Yun MA Jun XU Gui Fa LI Ying GUO Hong Wei DU Lin MA Guan Sheng 2012Biomedical and Environmental Sciences2012,25,2:16
12Thorombolytic therapy with rescue percutaneous coronary intervention versus primary percutaneous coronary intervention in patients with acute myocardial infarction: a multicenter randomized clinical trial显示文摘背景尽管有营救的 thrombolytic 治疗经皮的冠的干预(一种总线标准)是为圣片断举起的普通治疗策略尖锐心肌的梗塞( STEMI ),欠缺的数据在它相对主要一种总线标准,和比较的功效上是可得到的因此是这 study.Methods 的目的这 multicenter ,开标签,使随机化,平行试用与 STEMI 在病人(年龄 70 年)上在 12 所医院里被进行在 12 以内介绍了症状发作的小时(吝啬的间隔> 3 个小时)。病人们被使随机化到三个组:主要一种总线标准组(n=101 ) ;recombinant staphylokinase (r-Sak ) 组(n=104 ) ;并且 recombinant 织物类型 plasminogen 使活跃之物(rt-PA ) 组(n=106 ) 。为分配到 thrombolytic 治疗手臂的所有病人,冠的 angiography 在药治疗以后在 90 分钟被执行证实梗塞相关的动脉(IRA ) 明显;营救一种总线标准与 TIMI 流动等级 2 在情况中被执行。赤裸金属的 stent 培植为所有病人被计划。 113.4 的一般水准纪录开始 thrombolytic 治疗( door-to-needle 时间)和 141.2 分钟在 IRA (到汽球时间的门)执行第一汽球通货膨胀的在它要求了的随机化以后的结果 IRA 明显( TIMI 流动等级 2 或 3 )和 TIMI 流动等级的 .Rates 3 是显著地更低的在在 90 点的 thrombolysis 组在过程的结束比在主要一种总线标准组在药治疗以后纪录(70.5%对98.0%, P < 0.0001 ,和53.0%对85.9%, P < 0.0001 ,分别地)。有 stenting 的营救一种总线标准在 thrombolytic 治疗手臂在 117 个病人(55.7%) 被执行。明显和 3 仍然是的 TIMI 流动等级的率显著地比在主要一种总线标准组在营救一种总线标准降低(88.9% 对 97.9% , P=0.0222,并且 68.4% 对 85.0% , P=0.0190,分别地) 。在 30 天治疗以后,死亡率在比在主要一种总线标准组与营救一种总线标准组相结合的 thrombolysis 是显著地更高的(7.1% 对 0, P=0.0034 ) 。 death/Ml 和流血复杂并发症的率比在主要一种总线标准组在与营救一种总线标准组一起的 thrombolysis 是显著地更高的(10.0%对1.0%, P=0.0380 ,并且28.10%对8.91%, P=0.0001 ,分别地)有营救一种总线标准的 .Conclusions Thrombolytic 治疗与冠的明显和 TIMI 流动等级的显著地更低的率被联系 3 ,但是与在 30 天的死亡, death/Ml 和出血性的复杂并发症的显著地更高的率,作为与在这组中国 SGAO Run-lin HAN Ya-ling YANG Xin-chun MAO Jie-ming FANG Wei-yi WANG Lei SHEN Wei-feng LI Zhan-quan JIA Guo-liang LU Shu-zheng WEI Meng ZENG Ding-yin CHEN Ji-lin QIN Xue-wen XU Bo DU Chang-hui 2010Chinese Medical Journal2010,,11:15
13Sensitive assay for measurement of volatile borneol, isoborneol, and the metabolite camphor in rat pharmacokinetic study of Borneolum (Bingpian) and Borneolum syntheticum (synthetic Bingpian)显示文摘Chen CHENG Xin-wei LIU Fei-fei DU Mei-juan LI Fang XU Feng-qing WANG Yang LIU Chuan LI Yan SUN 2013Acta Pharmacologica Sinica2013,34,10:15
14Pharmacokinetics and disposition of monoterpene glycosides derived from Paeonia lactiflora roots (Chishao) after intravenous dosing of antiseptic XueBiJing injection in human subjects and rats显示文摘瞄准:从 Paeonia lactiflora 根(Chishao ) 导出的 Monoterpene glycosides 被相信为防腐草药的注射 XueBiJing pharmacologically 重要。这研究被设计描绘 monoterpene glycosides.Methods 的 pharmacokinetics 和布置:到 Chishao monoterpene glycosides 的全身的暴露在收到静脉内的注入和 XueBiJing 注射的多重注入的人的题目被估计,由对主要传播混合物的 pharmacokinetics 的评价列在后面。支持的老鼠研究也被执行。膜渗透和血浆蛋白质绑定在 vitro.Results 被估计:18 monoterpene glycosides 的一个总数在 XueBiJing 注射被检测(内容层次, 0.001-2.47 mmol/L ) ,并且 paeoniflorin 说明了检测的 monoterpene glycosides 的 85.5% 全部的剂量。在人的题目,未改变的 paeoniflorin 与 1.2-1.3 h 的消除一半生活展出了全身的暴露的可观的层次;没有重要代谢物被检测。Oxypaeoniflorin 和 albiflorin 展出了低暴露层次,并且留下的次要的 monoterpene glycosides 可以忽略或未被发现。Glomerular-filtration-based 肾的排泄是 paeoniflorin 的主要消除小径,它血浆蛋白质糟糕一定。在老鼠,当剂量被增加, paeoniflorin 的全身的暴露水平按比例增加了。老鼠肺,心,和 paeoniflorin 的肝暴露层次比血浆水平低,与肾水平的例外,它是比血浆水平大的 4.3 褶层;大脑穿入被差的膜 permeability.Conclusion 限制:由于它的重要全身的暴露和适当 pharmacokinetic 侧面,以及以前报导了防腐性质, paeoniflorin 是治疗学的重要性的有希望的 XueBiJing 成分。Chen CHENG Jia-zhen LIN Li LI Jun-ling YANG Wei-wei JIA Yu-hong HUANG Fei-fei DU Feng-qing WANG Mei-juan LI Yan-fen LI Fang XU Na-ting ZHANG Olajide E. OLALEYE Yan SUN Jian LI Chang-hai SUN Gui-ping ZHANG Chuan LI 2016Acta Pharmacologica Sinica2016,37,4:15
15Laboratory simulation on acoustic well-logging with phased array transmitter显示文摘Two small scale acoustic phased arrays with 4 elements have been designed and assembled in the laboratory. Experiments have been carried out with them. It is found that both directivity and radiation lobe width of the phased array can be regulated by changing the time delay between the input signals on neighboring elements. Results measured are in good agreement with those calculated. By using the phased array as an acoustic transmitter and hydrophone as a receiver, small scale acoustic well-logging simulations have been carried out both on an aluminum model well and on a concrete one. Experimental results show that, by increasing the time delay of the input signals on neighboring elements, the steered radiation angle of the phased array becomes larger and larger, and generation conditions of the refracted compressional wave and the refracted shear wave are reached successively, and the refracted compressional wave, the refracted shear wave and the Stoneley wave axe strengthened, respectively. Therefore, by choosing element spacing of a phased array and acoustic wave frequency appropriately, the main radiation lobe of the phased array can be widened to cover the first critical angle of all kinds of formations, which makes it possible to apply phased array acoustic well-logging in any formation continuously without regulating directivity of the phased array.QIAO Wenxiao CHEN Xuelian DU Guangsheng FANG Jun LI Gang(Faculty of Natural Resources and Information Technology, University of Petroleum Beijing 102249) 2003Chinese Journal of Acoustics2003,22,4:14
16NEECF: a project of nutrient enrichment experiments in China’s forests显示文摘Anthropogenic nitrogen(N)emissions to atmosphere have increased dramatically in China since 1980s,and this increase has aroused great concerns on its ecological impacts on terrestrial ecosystems.Previous studies have showed that terrestrial ecosystems in China are acting as a large carbon(C)sink,but its potential in the future remains largely uncertain.So far little work on the impacts of the N deposition on C sequestration in China’s terrestrial ecosystems has been assessed at a national scale.Aiming to assess and predict how ecological processes especially the C cycling respond to the increasing N deposition in China’s forests,recently researchers from Peking University and their partners have established a manipulation experimental network on the ecological effects of the N deposition:Nutrient Enrichment Experiments in China’s Forests Project(NEECF).The NEECF comprises 10 experiments at 7 sites located from north to south China,covering major zonal forest vegetation in eastern China from boreal forest in Greater Khingan Mountains to tropical forests in Hainan Island.This paper introduces the framework of the NEECF project and its potential policy implications.Enzai Du Zhang Zhou Peng Li Xueyang Hu Yuecun Ma Wei Wang Chengyang Zheng Jianxiao Zhu Jin-Sheng He Jingyun Fang 2013Journal of Plant Ecology2013,6,5:13
17China Patient-centered Evaluative Assessment of Cardiac Events Prospective Study of Acute Myocardial Infarction: Study Design显示文摘Rachel P Dreyer Xi Li Xue Du Nicholas S Downing Li Li Hai-Bo Zhang Fang Feng Wen-Chi Guan Xiao Xu Shu-Xia Li Zhen-Qiu Lin Frederick A Masoudi John A Spertus Harlan M Krumholz Li-Xin Jiang 2016Chinese Medical Journal2016,,1:13
18Serum Uric Acid is Associated with the Predicted Risk of Prevalent Cardiovascular Disease in a Community-dwelling Population without Diabetes显示文摘Objective To examine the association between serum uric acid levels and cardiovascular disease risk among individuals without diabetes. Methods We investigated the association between serum uric acid levels and the risk of prevalent cardiometabolic diseases, 10-year Framingham risk for coronary heart disease, and 10-year risk for atherosclerotic cardiovascular diseases(ASCVD) among 8,252 participants aged ≥ 40 years without diabetes from Jiading district, Shanghai, China. Results Body mass index, waist circumference, blood glucose, glycated hemoglobin, blood pressure, and serum lipids increased progressively across the sex-specific quartiles of uric acid(all P trend < 0.05). Compared with individuals in the lowest quartile, those in the higher quartiles had a significantly higher prevalence of obesity, hypertension, and dyslipidemia(all P trend < 0.05). A fully adjusted logistic regression analysis revealed that individuals in the highest quartile had an increased risk of predicted cardiovascular disease compared with those in the lowest quartile of uric acid. The multivariate adjusted odds ratios(ORs) [95% confidence intervals(CIs)] for the highest quartiles for high Framingham risk were 3.00(2.00-4.50) in men and 2.95(1.08-8.43) in women. The multivariate adjusted ORs(95% CIs) for the highest quartile for high ASCVD risk were 1.93(1.17-3.17) in men and 4.53(2.57-7.98) in women. Conclusion Serum uric acid level is associated with an increased risk of prevalent obesity, hypertension, dyslipidemia, 10-year Framingham risk for coronary heart disease, and 10-year risk for ASCVD among Chinese adults without diabetes.CHENG Di DU Rui WU Xue Yan LIN Lin PENG Kui MA Li Na XU Yu XU Min CHEN Yu Hong BI Yu Fang WANG Wei Qing DAI Meng LU Jie Li 2018Biomedical and Environmental Sciences2018,31,2:13
19Downregulation of serum mi R-17 and mi R-106b levels in gastric cancer and benign gastric diseases显示文摘Altered micro RNA(mi RNA) associated with gastric cancer(GC) development and mi R-17 and mi R-106 b were differentially expressed in GC tissues. This study detected serum levels of mi R-17 and mi R-106 b expression in GC, benign gastric disease(BGD) and healthy controls to assess them as tumor markers for GC. Serum samples from 40 GC, 32 BGD(10 gastric ulcer, 14 gastric polyps, and 8 gastric ulcer with polyps) and 36 healthy individuals were subjected to quantitative reverse transcription polymerase chain reaction(q RT-PCR) analysis of mi R-17 and mi R-106 b expression. The data showed that the serum levels of mi R-17 and mi R-106 b were significantly reduced in healthy individuals and BGD patients compared to GC patients. There was a significant association of mi R-17 and mi R-106 b expression with age, but not with other clinicopathological features, such as gender, tumor differentiation, stage and lymphatic metastasis. Further analysis showed that, in discriminating GC patients from healthy controls, mi R-17 could yield a receiver-operating characteristic(ROC) area under the curve(AUC) of 0.879 with 80.6% sensitivity and 87.5% specificity and mi R-106 b could yield an AUC of 0.856 with 75.0% sensitivity and 92.5% specificity. The combined AUC of mi R-17 and mi R-106 b was 0.913 with 83.3% sensitivity and 87.5% specificity. Collectively, these data suggest that detection of serum mi R-17 and mi R-106 b levels should be further evaluated as novel non-invasive biomarkers in early GC detection and surveillance of disease progression.Qinghai Zeng Cuihong Jin Wenhang Chen Fang Xia Qi Wang Fan Fan Juan Du Yihang Guo Changwei Lin Kaiyan Yang Jingjing Li Xiaowei Peng Xiaorong Li Ke Cao 2014Chinese Journal of Cancer Research2014,26,6:12
20An Estimation of Internal Soliton Forces on a Pile in the Ocean显示文摘Internal soliton forces on oil-platform piles in the ocean are estimated with the Morison Formula. Different from sur- face wave forces, which change only in magnitude along a pile, internal soliton forces can be distributed over the entire pile in the water and they change not only in magnitude but also in direction with depth. Our calculations show that the maximum total force caused by a soliton with its associated current of 2.1 m s-1 is nearly equal to the maximum total force exerted by a surface wave with a wavelength of 300 m and a wave-height of 18 m. The total internal soliton force is large enough to affect the operations of marine oil platforms and other facilities. Therefore, the influence of internal solitons should not be neglected in the design of oil platforms.DU Tao SUN Li ZHANG Yijun BAO Xianwen FANG Xinhua 2007Journal of Ocean University of China2007,6,2:12
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