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一种由全球水循环产生的可能重要的CO_2汇 被引量:81
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作者 刘再华 wolfgang Dreybrodt 王海静 《科学通报》 EI CAS CSCD 北大核心 2007年第20期2418-2422,共5页
关于全球CO2汇的位置、大小、变化和机制目前仍不确定,还存有争议.在理论计算和野外观测数据证明的基础上发现,可能存在一种由全球水循环产生的重要的CO2汇(以溶解无机碳-DIC的形式).这个汇达到0.8013PgC/a(约占人类活动排放CO2总量的10... 关于全球CO2汇的位置、大小、变化和机制目前仍不确定,还存有争议.在理论计算和野外观测数据证明的基础上发现,可能存在一种由全球水循环产生的重要的CO2汇(以溶解无机碳-DIC的形式).这个汇达到0.8013PgC/a(约占人类活动排放CO2总量的10.1%,或占所谓的遗漏CO2汇的28.6%),它是由水对CO2的溶解吸收形成的,并随着碳酸盐的溶解及水生植物光合作用对CO2的消耗的增加而显著增加.这部分汇中有0.5188PgC/a通过海上降水(0.2748PgC/a)和陆地河流(0.244PgC/a)进入海洋,有0.158PgC/a再次释放进入大气,还有0.1245PgC/a储存在陆地水生生态系统中.因此,净沉降是0.6433PgC/a.随着全球变暖引起的全球水循环的加强、CO2和大气圈中碳酸盐粉尘的增加,还有造林地区的增多(会引起土壤CO2的增加进而导致水中DIC浓度的增大),这部分汇也可能增加. 展开更多
关键词 CO2汇 全球水循环 CO2吸收 碳酸盐溶解 溶解无机碳 水生植物光合作用
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Clinical characteristics and outcome of a cohort of 101 patients with hepatocellular carcinoma 被引量:61
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作者 Christian Rabe Tillmann Pilz +4 位作者 Christoph Klostermann Marc Berna Hans H.Schild Tilman Sauerbruch wolfgang H.Caselmann 《World Journal of Gastroenterology》 SCIE CAS CSCD 2001年第2期208-215,共8页
AIM: To conduct a cohort study of 101 patients with hepatocellular carcinoma (HCC) presenting to a tertiary care medical referral center in Germany between 1997 and 1999. METHODS AND RESULTS: Data were retrospectively... AIM: To conduct a cohort study of 101 patients with hepatocellular carcinoma (HCC) presenting to a tertiary care medical referral center in Germany between 1997 and 1999. METHODS AND RESULTS: Data were retrospectively analyzed by chart review. In 95 cases (72 males and 23 females) sufficient data were available for analysis. Twenty five (29%) of 85 patients were HBsAg or anti HBc positive, 21/85 (25%) were anti HCV positive, and 6/85 (7%) were positive for both HBV and HCV-markers. Age was significantly lower in HBV positive patients than in the other two groups. Thirty one (34%) of 90 patients had histories of alcohol abuse. In 79/94 (84%) patients, cirrhosis was diagnosed. Of these cirrhotic patients, 29/79 (37%) belonged to Child Pugh's group (CHILD) A, 32/79 (40%) to CHILD B, and 18/79 (23%) to CHILD C. AFP was elevated in 61/91 (67%) patients. A single tumor nodule was found in 38/94 (40%), more than one nodule in 31/94 (34%), and 25/94 (26%) had a diffusely infiltrating tumor, i.e. the tumor margins could not be seen on imaging procedures. Portal vein thrombosis was present in 19/94 (20%). Imaging data consistent with lymph node metastases were found in 10/92 (11%), while distant metastases were found in 8/93 (9%). According to Okuda 28/94 (30%) were grouped to stage I, 53/94 (56%) were grouped to stage II, and 13/94 (14%) were grouped to stage II. Survival data were available for 83 patients. The Kaplan-Meier estimate for median survival was 8 4 months. Factors influencing survival were the Okuda score, the presence of portal vein thrombosis, and the presence of ascites. The presence of non complicated liver cirrhosis by itself, distant metastases, or infection with hepatitis viruses did not influence survival. AFP positivity by itself did not influence survival, though patients with an AFP value greater than 100 microg/L did experience shortened survival. Treatment besides tamoxifen or supportive care was associated with prolonged survival. The influence of therapy on survival was most pronounced in Okuda 展开更多
关键词 Adult Aged Aged 80 and over Carcinoma Hepatocellular Cohort Studies Female Germany Hepatitis B Hepatitis C Humans Liver Cirrhosis Alcoholic Liver Neoplasms Male Middle Aged Research Support Non-U.S. Gov't Retrospective Studies Risk Factors Survival Analysis
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Anaerobic microbiologically influenced corrosion mechanisms interpreted using bioenergetics and bioelectrochemistry: A review 被引量:53
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作者 Yingchao Li Dake Xu +6 位作者 Changfeng Chen Xiaogang Li Ru Jia Dawei Zhang wolfgang Sand Fuhui Wang Tingyue Cu 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2018年第10期1713-1718,共6页
Microbiologically influenced corrosion (MIC) is a major cause of corrosion damages, facility failures, and financial losses, making MIC an important research topic. Due to complex microbiological activities and a la... Microbiologically influenced corrosion (MIC) is a major cause of corrosion damages, facility failures, and financial losses, making MIC an important research topic. Due to complex microbiological activities and a lack of deep understanding of the interactions between biofilms and metal surfaces, MIC occurrences and mechanisms are difficult to predict and interpret. Many theories and mechanisms have been pro- posed to explain MIC. In this review, the mechanisms of MIC are discussed using hioenergetics, microbial respiration types, and biofilm extracellular electron transfer (EET). Two main MIC types, namely EET-MIC and metabolite MIC (M-ME), are discussed. This brief review provides a state of the art insight into MIC mechanisms and it helps the diagnosis and prediction of occurrences of MIC under anaerobic conditions in the oil and gas industry. 展开更多
关键词 Microbiologically influenced corrosion BIOENERGETICS BIOFILM BIOELECTROCHEMISTRY MIC classification Extracellular electron transfer (EET)
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Significance of the carbon sink produced by H_2O–carbonate–CO_2–aquatic phototroph interaction on land 被引量:49
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作者 刘再华 wolfgang Dreybrodt 《Science Bulletin》 SCIE EI CAS CSCD 2015年第2期182-191,I0001,共11页
One of the most important questions in the science of global change is how to balance the atmospheric CO2 budget. There is a large terrestrial missing carbon sink amounting to about one billion tonnes of carbon per an... One of the most important questions in the science of global change is how to balance the atmospheric CO2 budget. There is a large terrestrial missing carbon sink amounting to about one billion tonnes of carbon per annum. The locations, magnitudes, variations, and mechanisms responsible for this terrestrial missing carbon sink are uncertain and the focus of much continuing debate. Although the positive feedback between global change and silicate chemical weathering is used in geochemical models of atmospheric CO2, this feedback is believed to operate over a long timescale and is therefore generally left out of the current discussion of human impact upon the carbon budget. Here, we show, by synthesizing recent findings in rock weathering research and studies into biological carbon pump effects in surface aquatic ecosystems, that the carbon sink produced by carbonate weathering based on the H2O- carbonate-CO2-aquatic phototroph interaction on land not only totals half a billion tonnes per annum, but also displays a significant increasing trend under the influence of global warming and land use change; thus, it needs to be included in the global carbon budget. 展开更多
关键词 Carbon sink H2O-carbonate-CO2- aquatic phototroph interaction Carbonate weathering Biological carbon pump Land aquatic ecosystem Global change
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Regulation of Pain and Itch by TRP Channels 被引量:43
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作者 Carlene Moore Rupali Gupta +2 位作者 Sven-Eric Jordt Yong Chen wolfgang B.Liedtke 《Neuroscience Bulletin》 SCIE CAS CSCD 2018年第1期120-142,共23页
Nociception is an important physiological process that detects harmful signals and results in pain perception. In this review, we discuss important experimental evidence involving some TRP ion channels as molecular se... Nociception is an important physiological process that detects harmful signals and results in pain perception. In this review, we discuss important experimental evidence involving some TRP ion channels as molecular sensors of chemical, thermal, and mechanical noxious stimuli to evoke the pain and itch sensations. Among them are the TRPA1 channel, members of the vanilloid subfamily (TRPV1, TRPV3, and TRPV4), and finally members of the melastatin group (TRPM2, TRPM3, and TRPMS). Given that pain and itch are pro-survival, evolutionarily-honed protective mechanisms, care has to be exercised when developing inhibitory/modulatory com- pounds targeting specific pain/itch-TRPs so that physio- logical protective mechanisms are not disabled to a degree that stimulus-mediated injury can occur. Such events have impeded the development of safe and effective TRPV1- modulating compounds and have diverted substantial resources. A beneficial outcome can be readily accom- plished via simple dosing strategies, and also by incorpo- rating medicinal chemistry design features during compound design and synthesis. Beyond clinical use, where compounds that target more than one channel might have a place and possibly have advantageous features, highly specific and high-potency compounds will be helpful in mechanistic discovery at the structure-function level. 展开更多
关键词 TRP channels PAIN ITCH Nociceptors - Inflammation Lipids Temperature HYPERALGESIA Nerve damage Neuropathic pain MECHANOTRANSDUCTION ALLODYNIA
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Assessment of metastatic liver disease in patients with primary extrahepatic tumors by contrast-enhanced sonography versus CT and MRI 被引量:39
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作者 Christoph F Dietrich wolfgang Kratzer +10 位作者 Deike Strobel Etienne Danse Robert Fessl Alfred Bunk Udo Vossas Karlheinz Hauenstein Wilhelm Koch wolfgang Blank Matthijs Oudkerk Dietbert Hahn Christian Greis 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第11期1699-1705,共7页
AIM: To evaluate contrast-enhanced ultrasonography (CEUS) using SonoVue in the detection of liver metastases in patients with known extrahepatic primary tumors versus the combined gold standard comprising CT, MRI a... AIM: To evaluate contrast-enhanced ultrasonography (CEUS) using SonoVue in the detection of liver metastases in patients with known extrahepatic primary tumors versus the combined gold standard comprising CT, MRI and clinical/histological data. METHODS: It is an international multicenter study, and there were 12 centres and 125 patients (64 males, 61 females, aged 59 ± 11 years) involved, with 102 patients per protocol. Primary tumors were colorectal in 35%, breast in 27%, pancreatic in 17% and others in 21%. CEUS using SonoVue was employed with a Iow-mechanical-index technique and contrast-specific software using Siemens Elegra, Philips HDI 5000 and Acuson Sequoia; continuous scanning for at least five minutes. RESULTS: CEUS with SonoVue increased significantly the number of focal liver lesions detected versus unenhanced sonography. In 31.4% of the patients, more lesions were found after contrast enhancement. The total numbers of lesions detected were comparable with CEUS (55), triple-phase spiral CT (61) and HRI with a liverspecific contrast agent (53). Accuracy of detection of metastatic disease (i.e. at least one metastatic lesion) was significantly higher for CEUS (91.2%) than for unenhanced sonography (81.4%) and was similar to that of triple-phase spiral CT (89.2 %). In 53 patients whose CEUS examination was negative, a follow-up examination 3-6 months later confirmed the absence of metastatic lesions in 50 patients (94.4%). CONCLUSION: CEUS is proved to be reliable in the detection of liver metastases in patients with known extrahepatic primary tumors and suspected liver lesions. 展开更多
关键词 CT MRI METASTASIS Detection SONOVUE
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Phase imaging with an untrained neural network 被引量:41
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作者 Fei Wang Yaoming Bian +5 位作者 Haichao Wang Meng Lyu Giancarlo Pedrini wolfgang Osten George Barbastathis Guohai Situ 《Light(Science & Applications)》 SCIE EI CAS CSCD 2020年第1期1258-1264,共7页
Most of the neural networks proposed so far for computational imaging(CI)in optics employ a supervised training strategy,and thus need a large training set to optimize their weights and biases.Setting aside the requir... Most of the neural networks proposed so far for computational imaging(CI)in optics employ a supervised training strategy,and thus need a large training set to optimize their weights and biases.Setting aside the requirements of environmental and system stability during many hours of data acquisition,in many practical applications,it is unlikely to be possible to obtain sufficient numbers of ground-truth images for training.Here,we propose to overcome this limitation by incorporating into a conventional deep neural network a complete physical model that represents the process of image formation.The most significant advantage of the resulting physics-enhanced deep neural network(PhysenNet)is that it can be used without training beforehand,thus eliminating the need for tens of thousands of labeled data.We take single-beam phase imaging as an example for demonstration.We experimentally show that one needs only to feed PhysenNet a single diffraction pattern of a phase object,and it can automatically optimize the network and eventually produce the object phase through the interplay between the neural network and the physical model.This opens up a new paradigm of neural network design,in which the concept of incorporating a physical model into a neural network can be generalized to solve many other CI problems. 展开更多
关键词 NEURAL NETWORK eventually
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Further Information of the Associated Li Deposits in the No.6 Coal Seam at Jungar Coalfield, Inner Mongolia, Northern China 被引量:37
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作者 SUN Yuzhuang ZHAO Cunliang +5 位作者 LI Yanheng WANG Jinxi ZHANG Jianya JIN Zhe LIN Mingyue wolfgang KALKREUTH 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2013年第4期1097-1108,共12页
Total 138 coal samples and 14 parting samples were taken from the No. 6 Seam of the Jungar Coalfield, Inner Mongolia. These samples were analysed by optical microscopy, sequential chemical extraction procedure (SCEP... Total 138 coal samples and 14 parting samples were taken from the No. 6 Seam of the Jungar Coalfield, Inner Mongolia. These samples were analysed by optical microscopy, sequential chemical extraction procedure (SCEP), inductively coupled plasma mass spectrometry (ICP-MS), X-ray powder diffraction (XRD), and scanning electron microscope in conjunction with an energy-dispersive X-ray spectrometer (SEM-EDX) analysis. The results indicate that the Li contents have reached the industrial grade of the coal associated Li deposit, and the total Li reserves have reached 2406600 tons, that is, 5157000 tons Li2O in the No. 6 seam in the Jungar Coalfield. The sequential chemical extraction procedure results suggest that the Li concentration is mainly related to inorganic matter. The minerals in the coals consist of kaolinite, boehmite, chlorite-group mineral, quartz, calcite, pyrite, siderite and amorphous clay material. Some Li could be absorbed by clay minerals in the Li-bearing coal seam. The chlorite phase?could be?most likely the host for a part of Li. The Yinshan Oldland should be the most possible source of Li of the coal. 展开更多
关键词 Li deposit industrial grade coal seam GEOCHEMISTRY Jungar Coalfield
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不同沉积环境及成熟度干酪根的碳氢同位素地球化学特征 被引量:37
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作者 王万春 徐永昌 +2 位作者 Manfred Schidlowski Eckhard Faber wolfgang Stahl 《沉积学报》 CAS CSCD 北大核心 1997年第A12期133-137,共5页
干酪根的碳同位素组成与源岩类型有无相关性存在不同认识,此次研究表明,在陆相沉积条件下,腐泥型干酪根相对富集轻碳同位素^(12)C(δ^(13)C一般小于-28‰),腐殖型干酪根相对富集重碳同位素^(13)C(δ^(13)C一般大于-26‰)。热模拟实验表... 干酪根的碳同位素组成与源岩类型有无相关性存在不同认识,此次研究表明,在陆相沉积条件下,腐泥型干酪根相对富集轻碳同位素^(12)C(δ^(13)C一般小于-28‰),腐殖型干酪根相对富集重碳同位素^(13)C(δ^(13)C一般大于-26‰)。热模拟实验表明,热演化过程对干酪根碳同位素不产生明显影响,但其H/C原子比随热演化程度增高而减小。已有资料对干酪根氢同位素研究较少,本文研究表明,干酪根的氢同位素组成主要与沉积介质的盐度有关。笔作者将干酪根氢同位素组成δD=-130‰作为源岩沉积介质为淡水和咸水一半咸水的界限,前者小于-130‰,后者大小-130‰。 展开更多
关键词 干酪根 碳同位素 氢同位素 成熟度 油气藏
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积雪和有机质土对青藏高原冻土活动层的影响 被引量:35
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作者 张伟 周剑 +5 位作者 王根绪 wolfgang Kinzelbach 程国栋 叶柏生 何晓波 李弘毅 《冰川冻土》 CSCD 北大核心 2013年第3期528-540,共13页
随着全球气候变暖,青藏高原冻土活动层正在逐渐加深,为了理解积雪和表层有机质土壤对冻土活动层的影响机理,一维水热耦合模型CoupModel被用于模拟气象驱动下土壤冻融的动态过程.基于祁连山冰沟和青藏高原唐古拉站长期监测数据,CoupMode... 随着全球气候变暖,青藏高原冻土活动层正在逐渐加深,为了理解积雪和表层有机质土壤对冻土活动层的影响机理,一维水热耦合模型CoupModel被用于模拟气象驱动下土壤冻融的动态过程.基于祁连山冰沟和青藏高原唐古拉站长期监测数据,CoupModel模型被成功的率定和验证.在冰沟站验证的模型被用于研究积雪对冻土活动层的影响,结果显示:目前较浅积雪情景(雪深<20cm)比完全忽略积雪的情景模拟的冬季土壤冻结深度深,说明青藏高原现状下较浅的积雪有利于冻土发育.原因是雪面较高的反照率造成地表吸收的太阳辐射减少,导致雪面温度较低,加之浅雪的阻热性能又较小,综合导致浅雪覆盖时表层土壤向大气释放的能量增加.但随着积雪深度逐渐增加,模拟的冬季土壤冻结深度反而越来越浅,说明较厚的积雪(>20cm的雪深)并不利于冻土的发育,主要是雪相对于空气低的热传导隔绝了表层土壤向大气的热损失.在唐古拉站验证的模型被用于研究有机质土对冻土活动层的影响,结果显示:随着有机质土壤深度增加,模拟的活动层夏季融化深度逐渐较小.有机质土壤较矿物质土壤低的热传导和高的热容性质减少了下伏土壤热状况对太阳辐射和气温波动的响应,说明有机质土有利于冻土的保护. 展开更多
关键词 青藏高原 冻土活动层 有机质土壤 积雪 CoupModel
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Hepatic steatosis is associated with an increased risk of carotid atherosclerosis 被引量:29
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作者 Henry V(o|¨)lzke Daniel M.Robinson +6 位作者 Volker Kleine Roland Deutscher wolfgang Hoffmann Jan Lüdemann Ulf Schminke Christof Kessler Ulrich John 《World Journal of Gastroenterology》 SCIE CAS CSCD 2005年第12期1848-1853,共6页
AIM: Although an association between hepatic steatosis and vascular risk factors has been described, direct relationships between fatty liver and atherosclerosis have not yet been investigated. The aim of the present ... AIM: Although an association between hepatic steatosis and vascular risk factors has been described, direct relationships between fatty liver and atherosclerosis have not yet been investigated. The aim of the present study has been to investigate those relationships. METHODS: The Study of Health in Pomerania examined a random population sample aged between 20 and 79 years. A study population of 4 222 subjects without hepatitis B and C infections and without liver cirrhosis was available for the present analysis. Hepatic steatosis was defined sonographically and intima-media thickness (IMT) as well as plaque prevalence were estimated by carotid ultrasound. RESULTS: The prevalence rate of hepatic steatosis was 29.9%. Among subjects aged ≥45 years, an association between hepatic steatosis and IMT of the carotid arteries was found in bivariate analysis, but not after adjustment for atherosclerotic risk factors. Individuals with fatty liver had more often carotid plaques than persons without fatty liver (plaque prevalence rate 76.8% vs 66.6%; P<0.001). This association persisted after adjustment for confounding factors and was predominantly present in subjects with no to mild alcohol consumption. CONCLUSION: There is an independent association between hepatic steatosis and carotid atherosclerotic plaques. Metabolic changes due to nonalcoholic fatty liver disease may explain this relationship. 展开更多
关键词 Hepatic steatosis Fatty liver ATHEROSCLEROSIS Study of Health in Pomerania
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也谈h指数的机会和局限性 被引量:26
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作者 wolfgang Gl nzel 刘俊婉 金碧辉 《科学观察》 2006年第1期10-11,共2页
传统的文献计量学指标工具是建立在包括均值、相对频次和分位数等简单统计函数基础之上的。这些基于论文和引文的统计已被证明是测度科研活动和科研绩效的一种有效工具,尤其是那些标准化的指标在宏观和中观层面的比较中很有优势。但是... 传统的文献计量学指标工具是建立在包括均值、相对频次和分位数等简单统计函数基础之上的。这些基于论文和引文的统计已被证明是测度科研活动和科研绩效的一种有效工具,尤其是那些标准化的指标在宏观和中观层面的比较中很有优势。但是,将其用在对科学家个人科研绩效的评估即微观层面的计估仍然存在很多问题。 展开更多
关键词 H指数 文献计量学指标 统计函数 科研绩效 科研活动 中观层面 微观层面 标准化 科学家 局限性
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结构有序、双重孔隙中孔炭材料的合成与表征(英文) 被引量:28
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作者 陆安慧 wolfgang Schmidt Ferdi Schütth 《新型炭材料》 SCIE EI CAS CSCD 2003年第3期181-185,共5页
 采用纳米涂层技术,以介孔分子筛SBA 15为模板,在其纳米孔道内引入糠醇/草酸溶液,经原位聚合,炭化后制得炭/SBA 15复合物。采用化学法脱除模板后制得具有规则结构的中孔炭。高分辨TEM表征结果显示该中孔炭是由纳米炭管相互联接、堆积而...  采用纳米涂层技术,以介孔分子筛SBA 15为模板,在其纳米孔道内引入糠醇/草酸溶液,经原位聚合,炭化后制得炭/SBA 15复合物。采用化学法脱除模板后制得具有规则结构的中孔炭。高分辨TEM表征结果显示该中孔炭是由纳米炭管相互联接、堆积而成,且具有六方对称结构。氮吸附结果显示其比表面积高达2000m2/g,孔径呈双峰分布。孔径相对较大的孔隙来源于SBA 15孔道经纳米涂层后所保留的孔隙;孔径相对较小的孔隙来源于SiO2移除后遗留的纳米孔空间。该方法可应用于以其他多孔氧化硅为模板制备新型纳米复合物的研究过程。 展开更多
关键词 中孔炭材料 合成 表征 孔径分布 介孔分子筛 模板
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Cryoablation of malignant liver tumors: results of a single center study 被引量:27
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作者 wolfgang Jungraithmayr Dieter Burger +1 位作者 Manfred Olschewski Stefan Eggstein 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS 2005年第4期554-560,共7页
BACKGROUND: Local ablative procedures such as cryo-surgery and thermo-ablation are increasingly employed as a supplement to liver resection for the therapy of primary and secondary liver tumors. It is still unclear if... BACKGROUND: Local ablative procedures such as cryo-surgery and thermo-ablation are increasingly employed as a supplement to liver resection for the therapy of primary and secondary liver tumors. It is still unclear if the survival time can be extended through local ablative procedures. This prospective study shows operative actions, complications and long-term follow-up of 19 patients undergoing cryotherapy. METHODS: Between 1997 and 1998, 19 patients underwent cryotherapy due to a non-resectable malignant liver tumor (17 patients with metastases of a colon carcinoma, 2 patients with a hepatocellular carcinoma). Twelve patients (63.2%) received cryotherapy only and seven patients (36.8%) received a combination of resection and cryotherapy. The median follow-up period was 23 months. RESULTS: In a total of 59 liver tumors (18 were resected and 41 received cryotherapy), 12 had cryotherapy only, and 7 had a combination of cryotherapy and resection. The 30-day lethality was 0%, and the rate of major complications was 21%. After one year, 27.3% of the patients were still recurrence- free. The recurrence rate for all tumors treated was 58.8%. The median survival time for all patients was 21 months. The one- and three-year survival rates were 62. 5% and 15.8%, respectively. CONCLUSIONS: The mortality for cryotherapy is low, but there is a high rate of complications and long-term tumor control is not sufficient. If local ablative procedures of hepatic lesions are to be performed, not laparotomy but percutaneous, percutaneous thermoablation should be discussed as an alternative therapeutic measure. 展开更多
关键词 CRYOTHERAPY COMPLICATIONS liver tumor SURVIVAL
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大别造山带北部卢镇关杂岩的U-Pb锆石年龄 被引量:23
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作者 江来利 wolfgang Siebel +2 位作者 陈福坤 刘贻灿 储东如 《中国科学(D辑)》 CSCD 北大核心 2005年第5期411-419,共9页
对大别造山带北部卢镇关杂岩的2个花岗片麻岩和1个斜长角闪岩的U-Pb锆石同位素年龄测定,得到其分别为740Ma和725Ma左右的原岩年龄.此结果表明卢镇关杂岩主要由新元古代酸性和基性岩浆岩组成,指示大别造山带东段北部不存在代表华北陆块... 对大别造山带北部卢镇关杂岩的2个花岗片麻岩和1个斜长角闪岩的U-Pb锆石同位素年龄测定,得到其分别为740Ma和725Ma左右的原岩年龄.此结果表明卢镇关杂岩主要由新元古代酸性和基性岩浆岩组成,指示大别造山带东段北部不存在代表华北陆块南缘古生代活动大陆边缘的岩石组合.据此年龄并结合地质和地球物理资料,将北淮阳带的中低变质岩分为以新元古代酸性和基性岩浆岩为主体的卢镇关杂岩,新元古代仙人冲组和祥云寨组及泥盆纪佛子岭群诸佛庵组和潘家岭组3部分,并推断南北陆块间的缝合线逆掩在北淮阳带之下. 展开更多
关键词 大别造山带 U-Pb 杂岩 锆石年龄 北部 同位素年龄测定 新元古代 地球物理资料 活动大陆边缘 北淮阳带 斜长角闪岩 花岗片麻岩 岩石组合 华北陆块 佛子岭群 岩浆岩 古生代 变质岩 泥盆纪 缝合线 基性 酸性 原岩 地质 南缘
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A possible important CO_2 sink by the global water cycle 被引量:23
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作者 LIU ZaiHua wolfgang DREYBRODT WANG HaiJing 《Chinese Science Bulletin》 SCIE EI CAS 2008年第3期402-407,共6页
The locations,magnitudes,variations and mechanisms responsible for the global CO2 sink are uncer-tain and under debate.Here,we show,based on theoretical calculations and evidences from field monitoring results,that th... The locations,magnitudes,variations and mechanisms responsible for the global CO2 sink are uncer-tain and under debate.Here,we show,based on theoretical calculations and evidences from field monitoring results,that there is a possible important CO2 sink(as DIC-dissolved inorganic carbon)by the global water cycle.The sink constitutes up to 0.8013 Pg C/a(or 10.1% of the total anthropogenic CO2 emission,or 28.6% of the missing CO2 sink),and is formed by the CO2 absorption of water and subsequent enhanced consumption by carbonate dissolution and aquatic plant photosynthesis.Of the sink,0.5188 Pg C/a goes to sea via precipitation over sea(0.2748 Pg C/a)and continental rivers(0.244 Pg C/a),0.158 Pg C/a is released to the atmosphere again,and 0.1245 Pg C/a is stored in the continental aquatic ecosystem.Therefore,the net sink could be 0.6433 Pg C/a.This sink may increase with the global-warming-intensified global water cycle,the increase in CO2 and carbonate dust in atmosphere,and reforestation/afforestation,the latter increasing soil CO2,and thus the concentration of the DIC in water. 展开更多
关键词 二氧化碳 全球水循环 碳酸盐分解 水生植物光合作用
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Diet therapy for inflammatory bowel diseases: The established and the new 被引量:22
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作者 Franziska Durchschein wolfgang Petritsch Heinz F Hammer 《World Journal of Gastroenterology》 SCIE CAS 2016年第7期2179-2194,共16页
Although patients with inflammatory bowel diseases(IBD) have a strong interest in dietary modifications as part of their therapeutic management, dietary advice plays only a minor part in published guidelines. The scie... Although patients with inflammatory bowel diseases(IBD) have a strong interest in dietary modifications as part of their therapeutic management, dietary advice plays only a minor part in published guidelines. The scientific literature shows that dietary factors might influence the risk of developing IBD, that dysbiosis induced by nutrition contributes to the pathogenesis of IBD, and that diet may serve as a symptomatic treatment for irritable bowel syndrome-like symptoms in IBD. The role of nutrition in IBD is underscored by the effect of various dietary therapies. In paediatric patients with Crohn's disease(CD) enteral nutrition(EN) reaches remission rates similar to steroids. In adult patients, however, EN is inferior to corticosteroids. EN is not effective in ulcerative colitis(UC). Total parenteral nutrition in IBD is not superior to steroids or EN. The use of specific probiotics in patients with IBD can be recommended only in special clinical situations. There is no evidence for efficacy of probiotics in CD. By contrast, studies in UC have shown a beneficial effect in selected patients. For patients with pouchitis, antibiotic treatment followed by probiotics, like VSL#3 or Lactobacillus GG, is effective. When probiotics are used, the risk of bacterial translocation and subsequent bacteremia has to be considered. More understanding of the normal intestinal microflora, and better characterization of probiotic strains at the phenotypic and genomic levels is needed as well as clarification of the mechanisms of action in different clinical settings. A FODMAP reduced diet may improve symptoms in IBD. 展开更多
关键词 ENTERAL NUTRITION PARENTERAL NUTRITION probiotics fermentable oligo- di- and monosaccharidesand POLYOLS Crohn's disease ULCERATIVE colitis
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埃森创伤问卷中文版的信度和效度研究 被引量:22
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作者 周娟 周肖榕 +12 位作者 李航 董非 王琳丽 鄢利福 刘欢 江瑞芳 余萍 邬晓艳 陈静 刘莉 Sefik Tagay wolfgang Senf 施琪嘉 《中华物理医学与康复杂志》 CAS CSCD 北大核心 2010年第2期121-124,共4页
目的对埃森大学医院心身科编制的埃森创伤问卷(ETI)进行初步的修订和信度效度检验。方法收集1120名受试者,分为心理患者组、躯体患者组、地震受灾组以及健康对照组,分别使用ETI进行测试,分析ETI中文版的信度、结构效度及效标效度... 目的对埃森大学医院心身科编制的埃森创伤问卷(ETI)进行初步的修订和信度效度检验。方法收集1120名受试者,分为心理患者组、躯体患者组、地震受灾组以及健康对照组,分别使用ETI进行测试,分析ETI中文版的信度、结构效度及效标效度。结果ETI共23个项目的总体信度克隆巴赫系数为0.94,各维度的相关性系数为0.69~0.80,提示有较好的内部一致性。因子分析得到3个因子结构(包括闯入、回避、分离);效标关联效度理想。结论修订的ETI具有较高的信度和效度。 展开更多
关键词 创伤心理学 问卷 信度 效度 诊断
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Proposal of an ultrasonographic classification for hepatic alveolar echinococcosis: Echinococcosis multilocularis Ulm classification-ultrasound 被引量:22
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作者 wolfgang Kratzer Beate Gruener +9 位作者 Tanja EM Kaltenbach Sarina Ansari-Bitzenberger Peter Kern Michael Fuchs Richard A Mason Thomas FE Barth Mark M Haenle Andreas Hillenbrand Suemeyra Oeztuerk Tilmann Graeter 《World Journal of Gastroenterology》 SCIE CAS 2015年第43期12392-12402,共11页
AIM: To establish an ultrasonographic classification based on a large sample of patients with confirmed hepatic alveolar echinococcosis(AE).METHODS: Clinical data and ultrasonography(US) findings of 185 patients(100 m... AIM: To establish an ultrasonographic classification based on a large sample of patients with confirmed hepatic alveolar echinococcosis(AE).METHODS: Clinical data and ultrasonography(US) findings of 185 patients(100 males; 85 females; mean age at diagnosis: 51.4 ± 17.6 years; mean age at time of US examination: 58.7 ± 18.2 years) were retrospectively reviewed with respect to the US morphology of hepatic AE lesions. The sonomorphological findings were grouped according to a five-part classification scheme.RESULTS: Application of the new classification resulted in the following distribution of sonomorphological patterns among the patients examined: hailstorm(54.1%); pseudocystic(13.5%); ossification(13.0%); hemangioma-like(8.1%); and metastasis-like(6.5%). Only 4.9% of lesions could not be assigned to a sonomorphological pattern.CONCLUSION: The sonomorphological classification proposed in the present study facilitates the diagnosis,interpretation and comparison of hepatic alveolar echinococcosis in routine practice and in the context of scientific studies. 展开更多
关键词 HEPATIC ECHINOCOCCOSIS ECHINOCOCCUS MUL tiloculari
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Detection of disseminated pancreatic cells by amplification of cytokeratin-19 with quantitative RT-PCR in blood,bone marrow and peritoneal lavage of pancreatic carcinoma patients 被引量:21
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作者 Katrin Hoffmann Christiane Kerner +4 位作者 wolfgang Wilfert Marc Mueller Joachim Thiery Johann Hauss Helmut Witzigmann 《World Journal of Gastroenterology》 SCIE CAS CSCD 2007年第2期257-263,共7页
AIM: To evaluate the diagnostic potential of cytokeratin-19 (CK-19) mRNA for the detection of disseminated tumor cells in blood, bone marrow and peritoneal lavage in patients with ductal adenocarcinoma of the pancr... AIM: To evaluate the diagnostic potential of cytokeratin-19 (CK-19) mRNA for the detection of disseminated tumor cells in blood, bone marrow and peritoneal lavage in patients with ductal adenocarcinoma of the pancreas. METHODS: Sixty-eight patients with pancreatic cancer (/7 = 37), chronic pancreatitis (n = 16), and non-pancreatic benign surgical diseases (/7 = 15, control group) were included in the study. Venous blood was taken preoperatively, intraoperatively and at postoperative d 1 and 10. Preoperative bone marrow aspirates and peritoneal lavage taken before mobilization of the tumor were analyzed. All samples were evaluated for disseminated tumor cells by CK-19-specific nested-PCR and quantitative fluorogenic RT-PCR. RESULTS: CK-19 mRNA expression was increased in 24 (64%) blood samples and 11 (30%) of the peritoneal lavage samples in the patients with pancreatic cancer. In 15 (40%) of the patients with pancreatic cancer, disseminated tumor cells were detected in venous blood and bone marrow and/or peritoneal lavage. In the peritoneal lavage, the detection rates were correlated with the tumor size and the tumor differentiation. CK-19 levels were increased in pT3/T4 and moderately/poorly differentiated tumors (G2/G3). Pancreatic cancer patients with at least one CK-19 mRNA-positive sample showed a trend towards shorter survival. Pancreatic cancer patients showed significantly increased detection rates of disseminated tumor cells in blood and peritoneal lavage compared to the controls and the patients with chronic pancreatitis. CONCLUSION: Disseminated tumor cells can be detected in patients with pancreatic ductal adenocarcinorna by CK-19 fluorogenic RT-PCR. In peritoneal lavage, detection rate is correlated with tumor stage and differentiation. In the clinical use, CK-19 is suitable for the distinction between malignant and benign pancreatic disease in combination with other tumor-specific markers. 展开更多
关键词 Tumor cell dissemination Pancreatic cancer CYTOKERATIN-19
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