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中国的经济增长能否持续?——一个生产率视角 被引量:178
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作者 郑京海 胡鞍钢 arne Bigsten 《经济学(季刊)》 2008年第2期777-808,共32页
中国经济转型的渐进式方法产生了持续的高增长。然而,近年来中国的经济学家们越来越认为这种增长是“粗放式”的,主要是靠增加投入获得的。我们对中国改革时期的经济进行研究,发现改革的措施往往导致对全要素生产率(TFP)的一次性... 中国经济转型的渐进式方法产生了持续的高增长。然而,近年来中国的经济学家们越来越认为这种增长是“粗放式”的,主要是靠增加投入获得的。我们对中国改革时期的经济进行研究,发现改革的措施往往导致对全要素生产率(TFP)的一次性的水平效应。中国现在需要调整其改革方案以促进生产率的持续增长。市场与所有制的改革,以及开放政策,改善了中国企业的经营环境,但加强建设发展完善的市场经济,还需要更为深入的制度改革。 展开更多
关键词 增长核算 全要素生产率 可持续增长
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龙门山冲断带的隆升和川西前陆盆地的沉降 被引量:164
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作者 刘树根 罗志立 +2 位作者 戴苏兰 Dennis arne C.J.L.Wilson 《地质学报》 EI CAS CSCD 北大核心 1995年第3期204-214,共11页
通过龙门山地区和川西前陆盆地岩石样品的裂变径迹和镜质体反射率的测定和计算机模拟得出:(1)松潘-甘孜褶皱带10Ma以来至少隆升了3—4km,隆升速率最低为0.3—0.4mm/a;(2)龙门山逆冲推覆构造带10Ma以来至少隆升了5—6km,隆升速率最低为0.... 通过龙门山地区和川西前陆盆地岩石样品的裂变径迹和镜质体反射率的测定和计算机模拟得出:(1)松潘-甘孜褶皱带10Ma以来至少隆升了3—4km,隆升速率最低为0.3—0.4mm/a;(2)龙门山逆冲推覆构造带10Ma以来至少隆升了5—6km,隆升速率最低为0.5—0.6mm/a;(3)龙门山滑脱拆离带60Ma以来隆升1—2km,隆升速率为0.016—0.032mm/a;(4)川西前陆盆地60Ma以来隆升了1.7—3km,隆升速率为0.028—0.05mm/a;(5)10Ma以来北川—映秀—小关子断裂西侧的隆升速率是其东侧隆升速率的40倍;(6)60Ma以前松潘—甘孜褶皱带的隆升与川西前陆盆地的沉降曲线呈镜象关系,即松潘—甘孜褶皱带隆升较快时,盆地沉降也较快。60Ma以来,川西前陆盆地也以隆升为主,但松潘—甘孜褶皱带的隆升速率要大得多;(7)川西前陆盆地的古地温梯度为25℃/km。 展开更多
关键词 裂变径迹 隆升 龙门山冲断带 川西 前陆盆地
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龙门山造山带-川西前陆盆地系统构造事件研究 被引量:100
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作者 刘树根 赵锡奎 +4 位作者 罗志立 徐国盛 王国芝 C.J.L.Wilson Dennis arne 《成都理工学院学报》 CAS CSCD 北大核心 2001年第3期221-230,共10页
通过对构造事件形成的产物 (岩浆岩、各种矿物等 )进行氩 -氩年龄测定、裂变径迹年龄测定、ESR年龄测定和计算机模拟 ,得出龙门山造山带 -川西前陆盆地系统自印支期以来 ,共发生了 7次构造事件 :(1)卡尼期末的构造事件 (D1 ) ,形成 S1 ... 通过对构造事件形成的产物 (岩浆岩、各种矿物等 )进行氩 -氩年龄测定、裂变径迹年龄测定、ESR年龄测定和计算机模拟 ,得出龙门山造山带 -川西前陆盆地系统自印支期以来 ,共发生了 7次构造事件 :(1)卡尼期末的构造事件 (D1 ) ,形成 S1 和 F1 ,并有区域低温动热变质作用 ;(2 )诺利期末的构造事件 (安县运动 ,D2 ) ,产生川西前陆盆地上三叠统须四段与下伏地层不整合接触和须四段砾岩的分布 ,并有较强的岩浆作用 ;(3)燕山期 (12 0~ 130 Ma,D3) ,有较强的岩浆作用和变质作用 ;(4 )喜马拉雅期 6 0 Ma左右的构造事件 (D4) ;(5 )喜马拉雅期 30~ 40Ma的构造事件 (D5 ) ;(6 )喜马拉雅期 2 0~ 2 5 Ma的构造事件 (D6 ) ;(7)喜马拉雅期 10 Ma的构造事件 (D7)。后 4次构造事件使龙门山造山带 展开更多
关键词 氩-氩年龄测定 裂变径迹年龄测定 ESR年龄测定 盆山系统 构造事件 前陆盆地 龙门山造山带
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1980—1994期间中国国有企业的效率、技术进步和最佳实践 被引量:54
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作者 郑京海 刘小玄 arne Bigsten 《经济学(季刊)》 2002年第3期521-540,共20页
本文在1980年到1994年的700个国有企业样本数据的基础上,采用数据包络法和Malmquist指数法,以生产率的增长为指标,考察了国有企业的生产绩效。与样本企业中的最佳实践企业相比,我们的经验研究结果表明,这些样本企业的技术效率普遍... 本文在1980年到1994年的700个国有企业样本数据的基础上,采用数据包络法和Malmquist指数法,以生产率的增长为指标,考察了国有企业的生产绩效。与样本企业中的最佳实践企业相比,我们的经验研究结果表明,这些样本企业的技术效率普遍较低。尽管生产率增长引人注目,但这一增长主要是通过技术进步而不是通过提高技术效率。进一步的回归分析结果表明,大型国企生产率增长的概率明显高于小型企业。最佳实践企业存在于沿海省份的大型国企当中的概率也比较高。工资激励和职工学历对于生产率的增长有显著的促进作用,企业开工率通过技术效率可在短期内影响生产率的增长。 展开更多
关键词 中国 国有企业 效率 技术进步 1980-1994年 生产率
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内蒙古温都尔庙群变质火山——沉积岩钐-钕同位素研究 被引量:27
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作者 聂凤军 裴荣富 +1 位作者 吴良士 arne Bjφrlykke 《科学通报》 EI CAS CSCD 北大核心 1994年第13期1211-1214,共4页
温都尔庙群主要系指在集(宁)-二(连浩特)铁路线以东,朱日和及其北部出露的一套中-浅变质海相火山沉积岩系.该套岩层以产出有温都尔庙式铁矿,非层序性蛇绿岩和高压变质矿物组合为国内外地质学界所关注,并且一直作为早古生代海沟存在的重... 温都尔庙群主要系指在集(宁)-二(连浩特)铁路线以东,朱日和及其北部出露的一套中-浅变质海相火山沉积岩系.该套岩层以产出有温都尔庙式铁矿,非层序性蛇绿岩和高压变质矿物组合为国内外地质学界所关注,并且一直作为早古生代海沟存在的重要标志.鉴于温都尔庙群岩层遭受到不同程度构造变动和变质作用以及缺失可信的古生物化石,其时代归属众说纷纭. 展开更多
关键词 温都尔庙群 沉积岩 钐-钕同位素
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A review on the performance of conventional and energy-absorbing rockbolts 被引量:22
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作者 Charlie C.Li Gisle Stjern arne Myrvang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2014年第4期315-327,共13页
This is a review paper on the performances of both conventional and energy-absorbing rockbolts manifested in laboratory tests. Characteristic parameters such as ultimate load, displacement and energy absorption are re... This is a review paper on the performances of both conventional and energy-absorbing rockbolts manifested in laboratory tests. Characteristic parameters such as ultimate load, displacement and energy absorption are reported, in addition to load-displacement graphs for every type of rockbolt. Conventional rockbolts refer to mechanical rockbolts, fully-grouted rebars and frictional rockbolts. According to the test results, under static pull loading a mechanical rockbolt usually fails at the plate; a fully-grouted rebar bolt fails in the bolt shank at an ultimate load equal to the strength of the steel after a small amount of displacement; and a frictional rockbolt is subjected to large displacement at a low yield load. Under shear loading, all types of bolts fail in the shank. Energy-absorbing rockbolts are developed aiming to combat instability problems in burst-prone and squeezing rock conditions. They absorb deformation energy either through ploughing/slippage at predefined load levels or through stretching of the steel bolt. An energy-absorbing rockbolt can carry a high load and also accommodate significant rock displacement, and thus its energy-absorbing capacity is high. The test results show that the energy absorption of the energy-absorbing bolts is much larger than that of all conventional bolts. The dynamic load capacity is smaller than the static load capacity for the energy-absorbing bolts displacing based on ploughing/slippage while they are approximately the same for the D-Bolt that displaces based on steel stretching. 展开更多
关键词 Rockbolt Laboratory bolt testEnergy-absorbing rockbolt Yield rockbolt Pull testShear test Dynamic testDrop test
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The Uplift of the Longmenshan Thrust Belt and Subsidence of the West Sichuan Foreland Basin 被引量:21
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作者 Liu Shugen, Luo Zhili, Dai Sulan, Changlu Institute of Technology, Chengdu, Sichuan, ChinaDennis arne Dalhousie U niversity, Canadaand C.J.L. Wilson Melbourne U niversity, Australia Jiang M inxi 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 1996年第1期16-26,共11页
Based on fission track dating of apatite, and measurement of vitrinite reflectance of rock samples from the Longmenshan (Longmen Mountain)area and the West Sichuan foreland basin and computer modelling it is concluded... Based on fission track dating of apatite, and measurement of vitrinite reflectance of rock samples from the Longmenshan (Longmen Mountain)area and the West Sichuan foreland basin and computer modelling it is concluded that (l)the Songpan-Garze fold belt has uplifted at least by 3-4 km with an uplift rate of no less than 0.3-0.4 mm/a since 10 Ma B.P.; (2) the Longmenshan thrust nappe belt has uplifted at least by 5-6 km with an uplift rate of more than 0.5- 0.6 mm /a since 10 Ma B.P.; (3) the Longmenshan detachment belt has uplifted by 1 - 2 km at a rate of 0.016-0.032 mm/a since 60 Ma B.P.; (4) the West Sichuan foreland basin has uplifted by 1.7-3 km at a rate of 0.028-0.05 mm/a since 60 Ma B.P.; (5) the uplift rate of the area on the west side of the Beichuan-Yingxiu-Xiaoguanzi fault for the last 10 Ma is 40 times as much as that on its east side; (6) the uplifting of the the Songpan - Garze fold belt and the subsidence of the West Sichuan foreland basin 60 Ma ago exhibit a mirro-image correlation, i.e. the rapid uplifting of the the Songpan-Garze fold belt was corresponding to the rapid subsidence of the basin;the Songpan-Garze fold belt has uplifted at a much greater rate than the West Sichuan foeland basin in the last 60 Ma;and (7) the palaeogeothermal gradient was 25℃ /km in the West Sichuan foreland basin. 展开更多
关键词 fission track uplift (subsidence) history basin modelling Longmenshan thrust belt West Sichuan foreland basin
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Transarterial chemoembolization using degradable starch microspheres and iodized oil in the treatment of advanced hepatocellular carcinoma: evaluation of tumor response, toxicity, and survival 被引量:16
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作者 Timm D Kirchhoff Joerg S Bleck +10 位作者 arne Dettmer Ajay Chavan Herbert Rosenthal Sonja Merkesdal Bernd Frericks Lars Zender Nisar P Malek Tim F Greten Stefan Kubicka Michael P Manns Michael Galanski 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2007年第3期259-266,共8页
BACKGROUND: In a multidisciplinary conference patients with advanced non-resectable hepatocellular carcinoma (HCC) were stratified according to their clinical status and tumor extent to different regional modalities o... BACKGROUND: In a multidisciplinary conference patients with advanced non-resectable hepatocellular carcinoma (HCC) were stratified according to their clinical status and tumor extent to different regional modalities or to best supportive care. The present study evaluated all patients who were stratified to repeated transarterial chemoembolization (TACE) from 1999 until 2003 in terms of tumor response, toxicity, and survival. A moderate embolizing approach was chosen using a combination of degradable starch microspheres (DSM) and iodized oil (Lipiodol) in order to combine anti-tumoral efficiency and low toxicity. METHODS: Fourty-seven patients were followed up prospectively. TACE treatment consisted of cisplatin (50 mg/m2), doxorubicin (50 mg/m2), 450-900 mg DSM, and 5-30 ml Lipiodol. DSM and Lipiodol were administered according to tumor vascularization. Patient characteristics,toxicity, and complications were outlined. In multivariate regression analyses of pre-treatment variables from a prospective database, predictors for tumor response and survival after TACE were determined. RESULTS: 112 TACE courses were performed (2.4±1.5 courses per patient). Mean maximum tumor size was 75 (± 43) mm, in 68% there was bilobar disease. Best response to TACE treatment was: progressive disease (PD) 9%, stable disease (SD) 55%, partial remission (PR) 36%, and complete remission (CR) 0%. Multivariate regression analyses identified tumor size ≤75 mm, tumor number ≤5, and tumor hypervascularization as predictors for PR. The overall 1-, 2-, and 3-year-survival rates were 75%, 59%, and 41%, respectively, and the median survival was 26 months. Low α-fetoprotein levels (<400 ng/ml) (Odds ratio=3.3) and PR as best response to TACE (Odds ratio=6.7) were significantly associated with long term survival (>30 months, R2=36%). Grade 3 toxicity occurred in 7.1% (n=8), and grade 4 toxicity in 3.6% (n=4) of all courses in terms of reversible leukopenia and thrombocytopenia. The incidence of major complications was 5.4% (n=6). All compli 展开更多
关键词 carcinoma hepatocellular transarterial chemoembolization degradable starch microspheres LIPIODOL tumor response SURVIVAL
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Epidemiology of perforated peptic ulcer:Age-and gender-adjusted analysis of incidence and mortality 被引量:16
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作者 Kenneth Thorsen Jon arne Sreide +2 位作者 Jan Terje Kvaly Tom Glomsaker Kjetil Sreide 《World Journal of Gastroenterology》 SCIE CAS 2013年第3期347-354,共8页
AIM:To investigate the epidemiological trends in inci-dence and mortality of perforated peptic ulcer(PPU)in a well-defined Norwegian population. METHODS:A retrospective,population-based,single-center,consecutive cohor... AIM:To investigate the epidemiological trends in inci-dence and mortality of perforated peptic ulcer(PPU)in a well-defined Norwegian population. METHODS:A retrospective,population-based,single-center,consecutive cohort study of all patients diag-nosed with benign perforated peptic ulcer.Included were both gastric and duodenal ulcer patients admitted to Stavanger University Hospital between January 2001 and December 2010.Ulcers with a malignant neoplasia diagnosis,verified by histology after biopsy or resection,were excluded.Patients were identified from the hospitals administrative electronic database using pertinent ICD-9 and ICD-10 codes(K25.1,K25.2,K25.5, K25.6,K26.1,K26.2,K26.5,K26.6).Additional searches using appropriate codes for relevant laparoscopic and open surgical procedures(e.g.,JDA 60,JDA 61,JDH 70 and JDH 71)were performed to enable a complete identification of all patients.Patient demographics,presentation patterns and clinical data were retrieved from hospital records and surgical notes.Crude and adjusted incidence and mortality rates were estimated by using national population demographics data. RESULTS:In the study period,a total of 172 patients with PPU were identified.The adjusted incidence rate for the overall 10-year period was 6.5 per 100 000 per year(95%CI:5.6-7.6)and the adjusted mortality rate for the overall 10-year period was 1.1 per 100 000 per year(95%CI:0.7-1.6).A non-significant decline in ad-justed incidence rate from 9.7 to 5.6 occurred during the decade.The standardized mortality ratio for the whole study period was 5.7(95%CI:3.9-8.2),while the total 30-d mortality was 16.3%.No difference in in-cidence or mortality was found between genders.However,for patients≥60 years,the incidence increased over 10-fold,and mortality more than 50-fold,compared to younger ages.The admission rates outside office hours were high with almost two out of three(63%) admissions seen at evening/night time shifts and/or during weekends.The observed seasonal variations in admissions were not statistic 展开更多
关键词 Perforated PEPTIC ULCER EPIDEMIOLOGY INCIDENCE MORTALITY SEASONAL variation
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Combination of repeated single-session percutaneous ethanol injection and transarterial chemoembolisation compared to repeated single-session percutaneous ethanol injection in patients with non-resectable hepatocellular carcinoma 被引量:14
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作者 arne Dettmer Timm D Kirchhoff +11 位作者 Michael Gebel Lars Zender Nisar P Malek Bernhard Panning Ajay Chavan Herbert Rosenthal Stefan Kubicka Susanne Krusche Sonja Merkesdal Michael Galanski Michael P Manns Joerg S Bleck 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第23期3707-3715,共9页
AIM: To evaluate the treatment effect of percutaneous ethanol injection (PEI) for patients with advanced, non-resectable HCC compared with combination of transarterial chemoembolisation (TACE) and repeated single... AIM: To evaluate the treatment effect of percutaneous ethanol injection (PEI) for patients with advanced, non-resectable HCC compared with combination of transarterial chemoembolisation (TACE) and repeated single-session PEI, repeated single-session PEI alone, repeated TACE alone, or best supportive care. METHODS: All patients who received PEI treatment during the study period were included and stratified to one of the following treatment modalities according to physical status and tumor extent: combination of TACE and repeated single-session PEI, repeated single-session PEI alone, repeated TACE alone, or best supportive care. Prognostic value of clinical parameters including Okuda-classification, presence of portal vein thrombosis, presence of ascites, number of tumors, maximum tumor diameter, and serum cholinesterase (CHE), as well as Child-Pugh stage, α-fetoprotein (AFP), fever, incidence of complications were assessed and compared between the groups. Survival was determined using Kaplan-Meier and multivariate regression analyses. 展开更多
关键词 HCC Single-session PEI TACE Survival Prediction
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Intermittent blood flow restriction does not reduce atrophy following anterior cruciate ligament reconstruction 被引量:14
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作者 Erik Iversen Vibeke Rostad arne Larmo 《Journal of Sport and Health Science》 SCIE 2016年第1期115-118,共4页
Background:A previous study has reported a 50% reduction in disuse atrophy of the quadriceps during the first 14 days after anterior cruciate ligament(ACL) reconstruction.A follow-up trial is needed to confirm these p... Background:A previous study has reported a 50% reduction in disuse atrophy of the quadriceps during the first 14 days after anterior cruciate ligament(ACL) reconstruction.A follow-up trial is needed to confirm these promising results.The present study aims to investigate the effect of an occlusion stimulus on quadriceps atrophy after ACL reconstruction.Methods:A total of 24 subjects participated in the study.They were randomized into two groups.Starting the 2nd day after surgery,the occlusion group received an occlusion stimulus for 5 min,followed by removal of the occlusive pressure for 3 min.This was repeated five times in one training session,twice daily.During the period of occlusive stimulus,the subjects performed 20 low load exercises for the quadriceps.The control group followed the same exercise protocol,but without the occlusion stimulus.Changes in quadriceps anatomical cross section area(ACSA) were measured using axial magnetic resonance(MR) images at 40% and 50% of the length of the femur.Results:Both groups had a significant reduction of quadriceps ACSA from 2 days before surgery to 16 days after surgery.During the intervention period,the occlusion group lost 13.8% ± 1.1%(mean ± SEM) and the control group lost 13.1% ± 1.0% of their quadriceps ACSA,respectively.There was no significant difference between the occlusion and control groups with regards to atrophy of the quadriceps muscles.Conclusion:In conflict with other studies using a similar protocol,application of blood flow restriction the first 14 days after ACL reconstruction did not reduce quadriceps ACSA muscle atrophy measured by MR in a population of athletes. 展开更多
关键词 ACL reconstruction Ascular occlusion Hypoxia ischemia Quadriceps atrophy
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Redox-Dependent Regulation of the Stress-Induced Zinc-Finger Protein SAP12 in Arabidopsis thaliana 被引量:12
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作者 Elke Stroeher Xin-Jia Wang Nils Roloff Peter Klein arne Husemann Karl-Josef Dietz 《Molecular Plant》 SCIE CAS CSCD 2009年第2期357-367,共11页
The stress-associated protein SAP12 belongs to the stress-associated protein (SAP) family with 14 members in Arabidopsis thaliana. SAP12 contains two AN1 zinc fingers and was identified in diagonal 2D redox SDS-PAGE... The stress-associated protein SAP12 belongs to the stress-associated protein (SAP) family with 14 members in Arabidopsis thaliana. SAP12 contains two AN1 zinc fingers and was identified in diagonal 2D redox SDS-PAGE as a protein undergoing major redox-dependent conformational changes. Its transcript was strongly induced under cold and salt stress in a time-dependent manner similar to SAP10, with high levels after 6 h and decreasing levels after 24 and 48 h. The tran- script regulation resembled those of the stress marker peroxiredoxin PrxllD at 24 and 48 h. Recombinant SAP12 protein showed redox-dependent changes in quaternary structure as visualized by altered electrophoretic mobility in non-reducing SDS polyacrylamide gel electrophoresis. The oxidized oligomer was reduced by high dithiothreitol concentrations, and also by E. coli thioredoxin TrxA with low dithiothreitol (DTF) concentrations or NADPH plus NADPH-dependent thioredoxin reductase. From Western blots, the SAP12 protein amount was estimated to be in the range of 0.5 ngμg^-1 leaf protein. SAP12 protein decreased under salt and cold stress. These data suggest a redox state-linked function of SAP12 in plant cells particularly under cold and salt stress. 展开更多
关键词 abiotic/environmental stress cold acclimation cell signaling gene expression ARABIDOPSIS A20 and AN1 Zinc finger domains redox regulation stress associated protein thioredoxin.
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Different antibiotic susceptibility between antrum and corpus of the stomach,a possible reason for treatment failure of Helicobacter pylori infection 被引量:11
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作者 Michael Selgrad Ina Tammer +7 位作者 Cosima Langner Jan Bornschein Julia Mei?le arne Kandulski Mariya Varbanova Thomas Wex Dirk Schlüter Peter Malfertheiner 《World Journal of Gastroenterology》 SCIE CAS 2014年第43期16245-16251,共7页
AIM: To assess whether antibiotic resistance varies between the antrum and corpus of the stomach of patients that are either Helicobacter pylori (H. pylori) therapy-naive or pre-treated.
关键词 Helicobacter pylori treatment Antibiotic susceptibility HETERORESISTANCE Antibiotic susceptibility
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Biliary cholesterol secretion: More than a simple ABC 被引量:10
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作者 arne Dikkers Uwe JF Tietge 《World Journal of Gastroenterology》 SCIE CAS CSCD 2010年第47期5936-5945,共10页
Biliary cholesterol secretion is a process important for 2 major disease complexes, atherosclerotic cardiovascular disease and cholesterol gallstone disease. With respect to cardiovascular disease, biliary cholesterol... Biliary cholesterol secretion is a process important for 2 major disease complexes, atherosclerotic cardiovascular disease and cholesterol gallstone disease. With respect to cardiovascular disease, biliary cholesterol secretion is regarded as the f inal step for the elimination of cholesterol originating from cholesterol-laden macrophage foam cells in the vessel wall in a pathway named reverse cholesterol transport. On the other hand, cholesterol hypersecretion into the bile is considered the main pathophysiological determinant of cholesterol gallstone formation. This review summarizes current knowledge on the origins of cholesterol secreted into the bile as well as the relevant processes and transporters involved. Next to the established ATP-binding cassette (ABC) transporters mediating the biliary secretion of bile acids (ABCB11), phospholipids (ABCB4) and cholesterol (ABCG5/G8), special attention is given to emerging proteins that modulate or mediate biliary cholesterol secretion. In this regard, the potential impact of the phosphatidylserine flippase ATPase class Ⅰ type 8B member 1, the Niemann Pick C1-like protein 1 that mediatescholesterol absorption and the high density lipoprotein cholesterol uptake receptor, scavenger receptor class B type Ⅰ, is discussed. 展开更多
关键词 CHOLESTEROL BILE GALLSTONE Atherosclerosis Reverse cholesterol transport LIPOPROTEINS High density lipoprotein Scavenger receptor class B type
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激光诱导击穿光谱技术对冶金样品中钢及炉渣的同时分析 被引量:10
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作者 BENGTSON arne THOMAS Bjork 《冶金分析》 CAS CSCD 北大核心 2009年第2期8-13,共6页
本研究的初衷是开发一种不均匀冶金样品中钢和炉渣的快速、同时分析方法,以用于工艺控制。该方法基于激光诱导击穿光谱技术(LIBS)。选择激光诱导击穿光谱技术是因为它既可以分析导电材料又可分析非导电材料,并且相对来说不易受样品形状... 本研究的初衷是开发一种不均匀冶金样品中钢和炉渣的快速、同时分析方法,以用于工艺控制。该方法基于激光诱导击穿光谱技术(LIBS)。选择激光诱导击穿光谱技术是因为它既可以分析导电材料又可分析非导电材料,并且相对来说不易受样品形状及表面光洁度的影响。产生的不均匀样品包含大量亚毫米级的渣颗粒,这些颗粒在单次LIBS分析中不能从周围的钢里面分离出来。因此提出了一种方法来对样品表面进行行扫描,扫描以大约0.5mm的分辨率和10 mm的步长来进行。激光的脉冲速率为20 Hz,扫描速度为1 mm/s。炉渣颗粒在行扫描中表现为钢的"污染区",在这个区域中有高浓度的一些元素,如钙、铝及硅。基于单点校准,提出了一种数学模型来逐步评定所得出的数据。首先,辨别出"干净"的钢区域,测定出钢的成分;第二步,测定出扫描总长度范围内的平均成分;最后一步,通过差减法计算出炉渣的成分平均值。这种方法被应用于几个多相取样器采集的样品的分析。发现钢中的碳、硅、锰、磷、硫及铝等元素都可被测定,仅有百分之几的相对标准偏差。而在炉渣中,分析的相对标准偏差会更高,几个重要元素在10%左右。这一方法有望进一步被开发应用于更小的非金属夹杂物的快速分析。 展开更多
关键词 激光烧蚀 光学发射 钢分析
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Changes in fish diversity and community structure in the central and southern Yellow Sea from 2003 to 2015 被引量:7
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作者 CHEN Yunlong SHAN Xiujuan +3 位作者 JIN Xianshi JOHANNESSEN arne YANG Tao DAI Fangqun 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2018年第3期805-817,共13页
The central and southern Yellow Sea is an important overwintering ground for many fish species in the Bohai Sea and Yellow Sea. For better understanding the status of the fish community after years of heavy exploitati... The central and southern Yellow Sea is an important overwintering ground for many fish species in the Bohai Sea and Yellow Sea. For better understanding the status of the fish community after years of heavy exploitation, variations in fish community structure and diversity were analyzed using data from bottom trawls during 2003–2015. Five fish assemblage indices all showed fluctuations without clear trends from 2003 to 2015, yet there were strong positive and significant correlations(P < 0.05) among them. The top-five dominant species accounted for a high weight percentage(49.7%–82.1%) in the annual fish catch. Multivariate analysis showed that two year groups could be pooled for the fish community: Group Ⅰ consisted of the years 2006, 2007, 2008 and 2015, while Group Ⅱ consisted of the years 2003, 2004, 2005, 2009, 2010 and 2014; the groups aggregated with 63.71% similarity, indicating a high level of similarity among all years. The multivariate dispersion values were 1.455 and 0.818 for Groups Ⅰ and Ⅱ, respectively, indicating greater variances in fish assemblage structure in Group Ⅰ than that in Group Ⅱ. Similarity of percentage analysis demonstrated that the average similarities for Group Ⅰ and Group Ⅱ were 71.58% and 67.51%, respectively. Size-spectra analysis revealed no consistent trend in the intercept and slope( P > 0.05); there were also no significant differences between the slope of the size-spectra and fishing ef fort. The catch per unit ef fort and mean individual weight analyses of the whole fish assemblage both showed a significantly decreasing trend over time. Overall, the results showed that the fish community structure in the central and southern Yellow Sea was relatively stable from 2003 to 2015 and the study could be used as a reference for supporting ecosystem-based fishery management. 展开更多
关键词 dominant species fish community structure multivariate analysis trawl data
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Diversity of parasitic cuckoos and their hosts in China 被引量:8
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作者 杨灿朝 梁伟 +5 位作者 Anton ANTONOV 蔡燕 Brd G.STOKKE Frode FOSSφY arne MOKSNES Eivin RφSKAFT 《Chinese Birds》 2012年第1期9-32,72,共25页
In this exposé we provide the first review of host use by brood parasitic cuckoos in a multiple-cuckoo system in China, based on our own long-term field data and a compilation of observations obtained from the li... In this exposé we provide the first review of host use by brood parasitic cuckoos in a multiple-cuckoo system in China, based on our own long-term field data and a compilation of observations obtained from the literature. In total, we found that 11 species of cuckoos utilized altogether 55 host species. These hosts belong to 15 families, in which Sylviidae, Turdidae and Timaliidae account for 22.6%, 20.8% and 17.0% of parasitism records, respectively. The Common Cuckoo (Cuculus canorus) had the widest range of host species, accounting for 45.5% of the total number of parasitized species (25 in 10 families) of all parasitism records and is the most frequent brood parasite in the country. Cuckoo species differed in their egg coloration and the extent of egg polymorphism with most of them, e.g. the Common Cuckoo, the Lesser Cuckoo (C. poliocephalus) and the Plaintive Cuckoo (Cacomantis merulinus) laying well mimetic eggs with respect to their hosts based on human being’s visual observations, while others such as the Large Hawk-cuckoo (C. sparverioides), the Himalayan Cuckoo (C. saturatus) and the Asian Emerald Cuckoo (Chrysococcyx maculatus) usually laid non-mimetic eggs. The use of cuckoo hosts and egg color variation in China are compared with those in other parts of their ranges in Asia. 展开更多
关键词 brood parasitism egg color host use multiple-cuckoo system egg polymorphism
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High-fat diet and oral infection induced type 2 diabetes and obesity development under different genetic backgrounds 被引量:4
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作者 Iqbal M.Lone Nadav Ben Nun +3 位作者 Aya Ghnaim arne S.Schaefer Yael Houri-Haddad Fuad A.Iraqi 《Animal Models and Experimental Medicine》 CAS CSCD 2023年第2期131-145,共15页
Background:Type 2 diabetes(T2D)is an adult-onset and obese form of diabetes caused by an interplay between genetic,epigenetic,and environmental components.Here,we have assessed a cohort of 11 genetically different col... Background:Type 2 diabetes(T2D)is an adult-onset and obese form of diabetes caused by an interplay between genetic,epigenetic,and environmental components.Here,we have assessed a cohort of 11 genetically different collaborative cross(CC)mouse lines comprised of both sexes for T2D and obesity developments in response to oral infection and high-fat diet(HFD)challenges.Methods:Mice were fed with either the HFD or the standard chow diet(control group)for 12 weeks starting at the age of 8 weeks.At week 5 of the experiment,half of the mice of each diet group were infected with Porphyromonas gingivalis and Fusobacterium nucleatum bacteria strains.Throughout the 12-week experimental period,body weight(BW)was recorded biweekly,and intraperitoneal glucose tolerance tests were performed at weeks 6 and 12 of the experiment to evaluate the glucose tolerance status of mice.Results:Statistical analysis has shown the significance of phenotypic variations between the CC lines,which have different genetic backgrounds and sex effects in different experimental groups.The heritability of the studied phenotypes was estimated and ranged between 0.45 and 0.85.We applied machine learning methods to make an early call for T2D and its prognosis.The results showed that classification with random forest could reach the highest accuracy classification(ACC=0.91)when all the attributes were used.Conclusion:Using sex,diet,infection status,initial BW,and area under the curve(AUC)at week 6,we could classify the final phenotypes/outcomes at the end stage of the experiment(at 12 weeks). 展开更多
关键词 collaborative cross genetic covariance HERITABILITY high-fat diet machine learning mouse model OBESITY type 2 diabetes
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中国的酸化问题——一项基于重庆—广州森林监测点研究结果的评估 被引量:6
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作者 Hans M. Seip Per Aagaard +12 位作者 Valter Angell Odd Eilertsen ThorjφrnLarssen Espen Lydersen Jan Mulder Ivar P. Muniz arne Semb 汤大钢 Rolf D. Vogt 肖劲松 赵大为 孔国辉 岳欣 《AMBIO-人类环境杂志》 1999年第6期524-530,576+509,共7页
中国经济的快速增长一直伴随着污染的加剧。本文在现场观测和文献研究的基础上讨论了酸性降水及其先兆的范围和影响。目前酸性降水的主要原因是二氧化硫的排放,但氮氧化物的排放也在增加。中国污染最严重地区的硫化合物沉降比东欧和中... 中国经济的快速增长一直伴随着污染的加剧。本文在现场观测和文献研究的基础上讨论了酸性降水及其先兆的范围和影响。目前酸性降水的主要原因是二氧化硫的排放,但氮氧化物的排放也在增加。中国污染最严重地区的硫化合物沉降比东欧和中欧经受严重污染的地区要高。中国南部很多地区的土壤和土壤水看来已经被酸化。这些地区的污染已经影响了森林和其他植物的生命力,特别是在位于和靠近城市地区的地方。地表水的酸化似乎在近期不会成为主要的区域性问题,但一些地区的河流,目前虽仅接受少量的酸沉降,却对酸化显得较敏感。 展开更多
关键词 森林监测点 评估 酸化 重庆-广州 环境污染 酸雨
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The Need of Industry to Go FAIR 被引量:7
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作者 Herman van Vlijmen Albert Mons +13 位作者 arne Waalkens Wouter Franke Arie Baak Gerbrand Ruiter Christine Kirkpatrick Luiz Olavo Bonino da Silva Santos Bert Meerman Renger Jellema Derk Arts Martijn Kersloot Sebastiaan Knijnenburg Scott Lusher Rudi Verbeeck Jean-Marc Neefs 《Data Intelligence》 2020年第1期276-284,320,321,322,共12页
The industry sector is a very large producer and consumer of data,and many companies traditionally focused on production or manufacturing are now relying on the analysis of large amounts of data to develop new product... The industry sector is a very large producer and consumer of data,and many companies traditionally focused on production or manufacturing are now relying on the analysis of large amounts of data to develop new products and services.As many of the data sources needed are distributed and outside the company,FAIR data will have a major impact,both by reducing the existing internal data silos and by enabling the efficient integration with external(public and commercial)data.Many companies are still in the early phases of internal data”FAIRification”,providing opportunities for SMEs and academics to apply and develop their expertise on FAIR data in collaborations and public-private partnerships.For a global Internet of FAIR Data&Services to thrive,also involving industry,professional tools and services are essential.FAIR metrics and certifications on individuals,data,organizations,and software,must ensure that data producers and consumers have independent quality metrics on their data.In this opinion article we reflect on some industry specific challenges of FAIR implementation to be dealt with when choices are made regarding”Industry GOing FAIR”. 展开更多
关键词 FAIR application
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