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Contrast-enhanced endoscopic ultrasound in discrimination between focal pancreatitis and pancreatic cancer 被引量:43
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作者 Michael Hocke Ewald schulze +2 位作者 Peter Gottschalk Theodor Topalidis Christoph F Dietrich 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第2期246-250,共5页
AIM: To evaluate the contrast-enhanced endosonography as a method of differentiating inflammation from pancreatic carcinoma based on perfusion characteristics of microvessels. METHODS: In 86 patients with suspected ... AIM: To evaluate the contrast-enhanced endosonography as a method of differentiating inflammation from pancreatic carcinoma based on perfusion characteristics of microvessels. METHODS: In 86 patients with suspected chronic pancreatitis (age: 62± 12 years; sex: f/m 38/48), pancreatic lesions were examined by conventional endo- scopic B-mode, power Doppler ultrasound and contrastenhanced power mode (Hitachi EUB 525, SonoVue, 2.4 mL, Bracco) using the following criteria for malignant lesions: no detectable vascularisation using conventional power Doppler scanning, irregular appearance of arterial vessels over a short distance using SonoVue contrastenhanced technique and no detectable venous vessels inside the lesion. A malignant lesion was assumed if all criteria were detectable [gold standard endoscopic ultrasound (EUS)-guided fine needle aspiration cytology, operation]. The criteria of chronic pancreatitis without neoplasia were defined as no detectable vascularisation before injection of SonoVue, regular appearance of vessels over a distance of at least 20 mm after injection of SonoVue and detection of arterial and venous vessels. RESULTS: The sensitivity and specifidty of conventional EUS were 73.2% and 83.3% respectively for pancreatic cancer. The sensitivity of contrast-enhanced EUS increased to 91.1% in 51 of 56 patients with malignant pancreatic lesion and the specificity increased to 93.3% in 28 of 30 patients with chronic inflammatory pancreatic disease.CONCLUSION: Contrast-enhanced endoscopic ultrasound improves the differentiation between chronic pancreatitis and pancreatic carcinoma. 展开更多
关键词 Endoscopic ultrasound Contrast enhancer Chronic pancreatitis Pancreatic cancer
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基于激光反射的土壤表面粗糙度测量装置设计与试验 被引量:30
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作者 蔡祥 孙宇瑞 +1 位作者 林剑辉 schulze Lammers P 《农业机械学报》 EI CAS CSCD 北大核心 2010年第1期68-71,91,共5页
为了实时获取土壤表面粗糙度数据,设计了一种基于激光三角测距原理的土壤表面粗糙度专用测量装置。采用激光扫描测距仪测量微位移,其精度高、响应速度快,测距分辨力高达0.1 mm,显著提高了土壤表面粗糙度的测量精度;借助于光电编码盘和... 为了实时获取土壤表面粗糙度数据,设计了一种基于激光三角测距原理的土壤表面粗糙度专用测量装置。采用激光扫描测距仪测量微位移,其精度高、响应速度快,测距分辨力高达0.1 mm,显著提高了土壤表面粗糙度的测量精度;借助于光电编码盘和螺杆组合实现高精度扫描定位;PDA作为上位机,农田环境下具有方便携带,大容量存储数据和智能化实时处理功能等优点。 展开更多
关键词 土壤 粗糙度 三角测距法 激光测距传感器 设计 试验
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Herbal traditional Chinese medicine and its evidence base in gastrointestinal disorders 被引量:21
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作者 Rolf Teschke Albrecht Wolff +2 位作者 Christian Frenzel Axel Eickhoff Johannes schulze 《World Journal of Gastroenterology》 SCIE CAS 2015年第15期4466-4490,共25页
Herbal traditional Chinese medicine(TCM) is used to treat several ailments, but its efficiency is poorly documented and hence debated, as opposed to modern medicine commonly providinge ffective therapies. The aim of t... Herbal traditional Chinese medicine(TCM) is used to treat several ailments, but its efficiency is poorly documented and hence debated, as opposed to modern medicine commonly providinge ffective therapies. The aim of this review article is to present a practical reference guide on the role of herbal TCM in managing gastrointestinal disorders, supported by systematic reviews and evidence based trials. A literature search using herbal TCM combined with terms for gastrointestinal disorders in Pub Med and the Cochrane database identified publications of herbal TCM trials. Results were analyzed for study type, inclusion criteria, and outcome parameters. Quality of placebo controlled, randomized, double-blind clinical trials was poor, mostly neglecting stringent evidence based diagnostic and therapeutic criteria. Accordingly, appropriate Cochrane reviews and meta-analyses were limited and failed to support valid, clinically relevant evidence based efficiency of herbal TCM in gastrointestinal diseases, including gastroesophageal reflux disease, gastric or duodenal ulcer, dyspepsia, irritable bowel syndrome, ulcerative colitis, and Crohn's disease. In conclusion, the use of herbal TCM to treat various diseases has an interesting philosophical background with a long history, but it received increasing skepticism due to the lack of evidence based efficiency as shown by high quality trials; this has now been summarized for gastrointestinal disorders, with TCM not recommended for most gastrointestinal diseases. Future studies should focus on placebo controlled, randomized, double-blind clinical trials, herbal product quality and standard criteria for diagnosis, treatment, outcome, and assessment of adverse herb reactions. This approach will provide figures of risk/benefit profiles that hopefully are positive for at least some treatment modalities of herbal TCM. Proponents of modern herbal TCM best face these promising challenges of pragmaticmodern medicine by bridging the gap between the two medicinal cultures. 展开更多
关键词 EVIDENCE based trials TRADITIONAL Chinesemedicine HERBAL TRADITIONAL CHINESE MEDICINE Gastrointestinaldisorders
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An Improved Frequency Domain Technique for Determining Soil Water Content 被引量:13
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作者 SUN Yu-Rui MA Dao-Kun +2 位作者 LIN Jian-Hui P. schulze LAMMERS L. DAMEROW 《Pedosphere》 SCIE CAS CSCD 2005年第6期805-812,共8页
For many years a soil water content sensor with low cost, reliability and sufficient accuracy has been desirable. Thus, an improved measurement method based on the frequency domain (FD) principle for determining soil ... For many years a soil water content sensor with low cost, reliability and sufficient accuracy has been desirable. Thus, an improved measurement method based on the frequency domain (FD) principle for determining soil water content was considered. Unlike other measurement principles, a new measurable index, η, which was independent of the output impedance and the amplitude of the oscillator while relying on the electrical impedance of a multi-pin probe, was pro- posed. Moreover, a model for processing the impedance of the multi-pin soil probe was developed, and several important electrical parameters for establishing their operating ranges applicable to this probe were evaluated. In order to confirm the theoretical analysis, an experiment was conducted with a 4-pin probe. Using the developed model, the relationship between the proposed index η and soil volumetric water content was shown to be linear (R2 = 0.9921). Thus, as the measurable index, η seemed satisfactory. 展开更多
关键词 dielectric constant frequency domain principle MEASUREMENT soil water content
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大田尺度下车载式土壤多参数测量方法研究 被引量:13
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作者 盛文溢 曾庆猛 +2 位作者 林剑辉 schulze Lammers P 孙宇瑞 《农业机械学报》 EI CAS CSCD 北大核心 2010年第11期188-192,共5页
应用自行研制的土壤含水量、电导率与耕作阻力车载测试系统以及EM38电导率测试仪,在特定的耕作和施肥管理制度试验田中进行大田尺度下的土壤多参数车载测量研究。在土壤参数空间分布信息基础上进行相关分析,结果表明复合传感器具备农田... 应用自行研制的土壤含水量、电导率与耕作阻力车载测试系统以及EM38电导率测试仪,在特定的耕作和施肥管理制度试验田中进行大田尺度下的土壤多参数车载测量研究。在土壤参数空间分布信息基础上进行相关分析,结果表明复合传感器具备农田土壤含水量和电导率变异响应能力,进一步建立了农田土壤电导率与含水量、耕作阻力以及施肥信息之间的统计预测模型。 展开更多
关键词 土壤参数 车载式测量 大田尺度 相关分析
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基于电磁阀的喷嘴直接注入式农药喷洒系统 被引量:13
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作者 蔡祥 Walgenbach Martin +2 位作者 Doerpmund Malte schulze Lammers Peter 孙宇瑞 《农业机械学报》 EI CAS CSCD 北大核心 2013年第6期69-72,200,共5页
设计了一种喷嘴直接注入式农药喷洒系统。通过与传统喷雾机械比较,简述了喷嘴直接注入式喷雾系统的结构和喷雾执行单元。为了实现农药定量注入,设计一种基于电磁原理的快速响应阀,并论述其工作原理和闭环控制方式。通过试验测试了喷雾... 设计了一种喷嘴直接注入式农药喷洒系统。通过与传统喷雾机械比较,简述了喷嘴直接注入式喷雾系统的结构和喷雾执行单元。为了实现农药定量注入,设计一种基于电磁原理的快速响应阀,并论述其工作原理和闭环控制方式。通过试验测试了喷雾执行单元的喷雾特性和喷杆组内各喷雾单元的一致性。结果表明在一定喷洒速率范围内,喷雾执行单元的喷水量和水压强存在多项式关系,农药注入量和PWM信号的高电平时间存在指数关系,其决定系数均高于0.9,并且同一喷杆组内6个喷雾单元的喷雾效果大体一致。 展开更多
关键词 直接注入式 电磁原理 快速响应阀门 脉宽调制 变量喷雾
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基于土壤表面粗糙度预测降雨影响下的表层土壤孔隙度 被引量:13
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作者 陈世超 林剑辉 +1 位作者 孙宇瑞 Peter schulze Lammers 《北京林业大学学报》 CAS CSCD 北大核心 2013年第2期69-74,共6页
根据表层土壤(0~40mm)孔隙度与降水量和土壤表面粗糙度之间的关系,提出一种预测表层土壤孔隙度的新方法。基于此目的,在德国波恩大学Dikopshof试验站,以两块采用不同耕作方式(地块1:铧式犁+圆盘耙;地块2:旋转锄+圆盘耙)处理过的耕地为... 根据表层土壤(0~40mm)孔隙度与降水量和土壤表面粗糙度之间的关系,提出一种预测表层土壤孔隙度的新方法。基于此目的,在德国波恩大学Dikopshof试验站,以两块采用不同耕作方式(地块1:铧式犁+圆盘耙;地块2:旋转锄+圆盘耙)处理过的耕地为研究对象,以耕后50d内的表层土壤孔隙度(TSP)与土壤表面粗糙度(SSR)为测量对象,分别采用地面激光扫描仪和气压比重计对TSP与SSR随时间的变化进行了连续测量,以研究TSP与SSR两者的动态关系。自2006到2009年,每年夏天进行1次重复试验,以研究不同降雨量对TSP与SSR关系的影响,并引入累计平均日降雨量(ARF)的影响指数。通过4a试验,得出结论:TSP随ARF增加而降低,随SSR降低而降低。在此基础上,建立了由ARF和SSR预测TSP的多元线性模型,且模型通过了F检验。结果表明,借助于地面激光扫描仪和降雨量数据,该模型可快速连续估算不同耕作方式下的土壤表层孔隙度。 展开更多
关键词 孔隙度 粗糙度测量 降雨
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Drug and herb induced liver injury: Council for International Organizations of Medical Sciences scale for causality assessment 被引量:11
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作者 Rolf Teschke Albrecht Wolff +3 位作者 Christian Frenzel Alexander Schwarzenboeck Johannes schulze Axel Eickhoff 《World Journal of Hepatology》 CAS 2014年第1期17-32,共16页
Causality assessment of suspected drug induced liver injury(DILI) and herb induced liver injury(HILI) is hampered by the lack of a standardized approach to be used by attending physicians and at various subsequent eva... Causality assessment of suspected drug induced liver injury(DILI) and herb induced liver injury(HILI) is hampered by the lack of a standardized approach to be used by attending physicians and at various subsequent evaluating levels. The aim of this review was to analyze the suitability of the liver specific Council for International Organizations of Medical Sciences(CIOMS) scale as a standard tool for causality assessment in DILI and HILI cases. PubMed database was searched for the following terms: drug induced liver injury; herb induced liver injury; DILI causality assessment; and HILI causality assessment. The strength of the CIOMS lies in its potential as a standardized scale for DILI and HILI causality assessment. Other advantages include its liver specificity and its validation for hepatotoxicity with excellent sensitivity, specificity and predictive validity, based on cases with a positive reexposure test. This scale allows prospective collection of all relevant data required for a valid causality assessment. It does not require expert knowledge in hepatotoxicity and its results may subsequently be refined. Weaknesses of the CIOMS scale include the limited exclusion of alternative causes and qualitatively graded risk factors. In conclusion, CIOMS appears to be suitable as a standard scale for attending physicians, regulatory agencies, expert panels and other scientists to provide a standardized, reproducible causality assessment in suspected DILI and HILI cases, applicable primarily at all assessing levels involved. 2014 Baishideng Publishing Group Co., Limited. All 展开更多
关键词 DRUG INDUCED LIVER INJURY DRUG hepatotox-icity HERB INDUCED LIVER INJURY Herbal HEPATOTOXICITY Causality assessment
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水文对土地利用和气候变化反应的模拟:以非洲南部为例 被引量:11
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作者 Roland schulze 孙颖 《AMBIO-人类环境杂志》 2000年第1期12-22,58,共11页
本文根据非洲南部的实际情况,确定出9个有关土地利用和气候变化的水文问题,每个问题都依据实地观察或模型模拟实例进行阐明。这9个问题是:①非洲南部的水文动态已经非常易变,因而使得气候变化难以察觉;②水文动态的变动被气候波动所放大... 本文根据非洲南部的实际情况,确定出9个有关土地利用和气候变化的水文问题,每个问题都依据实地观察或模型模拟实例进行阐明。这9个问题是:①非洲南部的水文动态已经非常易变,因而使得气候变化难以察觉;②水文动态的变动被气候波动所放大;③水文对土地利用变化的反应高度敏感;④土地利用的局部范围突变可能比区域范围渐变对水文的意义更为重大;⑤土地利用的变化常常使已经多变的河流动态更加恶化;⑥详尽的空间信息对评价重大的土地利用的影响是至关重要的;⑦水文体系的主要成分对气候变化的反应是迥异的;⑧在发展中国家季节间的气候变化可能会比以十年为单位的气候变化更重要;⑨有必要确定出一个区域中的一些水文敏感地段。 展开更多
关键词 土地利用 气候变化 水文学 水文模拟 非洲南部
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土壤圆锥指数、水分与容重耦合模型的试验比较--Ⅰ.模型性能的统计检验与容重预测 被引量:10
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作者 林剑辉 孙宇瑞 +1 位作者 曾庆猛 P. schulze Lammers 《应用基础与工程科学学报》 EI CSCD 2008年第6期779-786,共8页
应用一种先进的双变量(土壤圆锥指数与水分)传感器复合测量系统,基于前人提出的土壤圆锥指数、水分与容重的4种半经验模型(Ayers,Upadhyaya,Busscher与Hernanz模型),以相关系数R2与统计残差作为检验指标,根据各模型的结构特点,结合两种... 应用一种先进的双变量(土壤圆锥指数与水分)传感器复合测量系统,基于前人提出的土壤圆锥指数、水分与容重的4种半经验模型(Ayers,Upadhyaya,Busscher与Hernanz模型),以相关系数R2与统计残差作为检验指标,根据各模型的结构特点,结合两种质地土壤(粘土与粉质壤土),针对容重预测精度与可应用性进行了深入试验研究.结果表明,Ayers和Upadhyaya模型虽然预测精度较高,但与土壤容重的解析关系为隐函数,在线辨识计算工作量只能取决迭代过程的收敛性,因而在实际应用上受到一定程度的限制.相比之下Busscher与Hernanz模型计算土壤容重方便快捷,但预测精度较低. 展开更多
关键词 模型 圆锥指数 土壤水分 容重
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陶瓷部件的浆料打印快速成型(英文) 被引量:10
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作者 王树海 Jang J H +1 位作者 schulze W A Pilgrim S M 《硅酸盐学报》 EI CAS CSCD 北大核心 2001年第4期344-349,共6页
采用Sanders公司的四打印头快速成型机进行了陶瓷部件的浆料打印成型实验 ,实际测试了所用四打印头快速成型机的打印工作条件 ,考察了石蜡和挥发性介质两种浆料技术路线 ,并采用石蜡为介质制备了钛酸钡陶瓷浆料 ,研究了其流变性能 .实... 采用Sanders公司的四打印头快速成型机进行了陶瓷部件的浆料打印成型实验 ,实际测试了所用四打印头快速成型机的打印工作条件 ,考察了石蜡和挥发性介质两种浆料技术路线 ,并采用石蜡为介质制备了钛酸钡陶瓷浆料 ,研究了其流变性能 .实验表明 ,虽然偶联剂的加入可以降低石蜡介质浆料的粘度 ,但是粘度足够低的可打印浆料的固相含量太低 [约 3 % (involume)以下 ] ,打印成型后不能完全烧结 ,因此 ,要通过打印成型出可完全烧结的陶瓷部件便只能采用挥发性液体作为浆料介质 。 展开更多
关键词 陶瓷部件 浆料 打印成型 烧结 四打印头快速成型机
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基于智能手机方位传感器的叶面积测量校正 被引量:7
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作者 高大帅 林剑辉 +2 位作者 余江斌 孙宇瑞 schulze Lammers Peter 《中国农业大学学报》 CAS CSCD 北大核心 2017年第6期128-134,共7页
针对使用智能手机野外测量叶面积时很难保证主光轴与叶平面垂直导致测量精度下降的问题,采用针孔相机模型和数字图像处理技术相结合的方法,对叶片平面和手机平面存在夹角时的叶面积测量建立误差校正模型并进行研究。1)以10片不同大小的... 针对使用智能手机野外测量叶面积时很难保证主光轴与叶平面垂直导致测量精度下降的问题,采用针孔相机模型和数字图像处理技术相结合的方法,对叶片平面和手机平面存在夹角时的叶面积测量建立误差校正模型并进行研究。1)以10片不同大小的椭圆形模拟叶片对开发的android App进行仿真测试,结果显示,叶面积测量值与理论值之间的决策系数高于97%,并且随着叶片与手机平面夹角的增大而减小,校正后的相对误差为-6%~8%,未校正的高达41.4%。2)以向日葵、番茄、辣椒和茄子等植物叶片对误差校正公式进行验证,结果显示,当夹角<15°,拍照高度为30~65cm时,叶面积测量的相对误差为-6%~6%,未校正的为-27.5%~25%。 展开更多
关键词 叶面积 针孔相机模型 ANDROID APP 误差校正
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牧场土壤含水率与坚实度空间变异与相关性分析 被引量:9
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作者 程强 孙宇瑞 +3 位作者 林剑辉 曾庆猛 schulze Lammers P Schellberg J 《农业机械学报》 EI CAS CSCD 北大核心 2009年第3期103-107,89,共6页
利用土壤水分/圆锥指数复合测量装置,应用精细农作技术体系网格定点测量与GPS定位,在一块面积约1.27 hm2的草地上获取了土壤含水率与坚实度空间分布基础数据,并针对采样过程中出现的数据缺失,用偏最小二乘法对数据进行修补。然后运用克... 利用土壤水分/圆锥指数复合测量装置,应用精细农作技术体系网格定点测量与GPS定位,在一块面积约1.27 hm2的草地上获取了土壤含水率与坚实度空间分布基础数据,并针对采样过程中出现的数据缺失,用偏最小二乘法对数据进行修补。然后运用克里格插值法进行数字化成图,并在此基础上分别对含水率与坚实度的空间变异性及两者的相关性做了分析。 展开更多
关键词 牧场草地 土壤 含水率 坚实度 空间变异 相关性
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Herbal hepatotoxicity:Challenges and pitfalls of causality assessment methods 被引量:9
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作者 Rolf Teschke Christian Frenzel +1 位作者 Johannes schulze Axel Eickhoff 《World Journal of Gastroenterology》 SCIE CAS 2013年第19期2864-2882,共19页
The diagnosis of herbal hepatotoxicity or herb induced liver injury(HILI) represents a particular clinical and regulatory challenge with major pitfalls for the causality evaluation.At the day HILI is suspected in a pa... The diagnosis of herbal hepatotoxicity or herb induced liver injury(HILI) represents a particular clinical and regulatory challenge with major pitfalls for the causality evaluation.At the day HILI is suspected in a patient,physicians should start assessing the quality of the used herbal product,optimizing the clinical data for completeness,and applying the Council for International Organizations of Medical Sciences(CIOMS) scale for initial causality assessment.This scale is structured,quantitative,liver specific,and validated for hepatotoxicity cases.Its items provide individual scores,which together yield causality levels of highly probable,probable,possible,unlikely,and excluded.After completion by additional information including raw data,this scale with all items should be reported to regulatory agencies and manufacturers for further evaluation.The CIOMS scale is preferred as tool for assessing causality in hepatotoxicity cases,compared to numerous other causality assessment methods,which are inferior on various grounds.Among these disputed methods are the Maria and Victorino scale,an insufficiently qualified,shortened version of the CIOMS scale,as well as various liver unspecific methods such as thead hoc causality approach,the Naranjo scale,the World Health Organization(WHO) method,and the Karch and Lasagna method.An expert panel is required for the Drug Induced Liver Injury Network method,the WHO method,and other approaches based on expert opinion,which provide retrospective analyses with a long delay and thereby prevent a timely assessment of the illness in question by the physician.In conclusion,HILI causality assessment is challenging and is best achieved by the liver specific CIOMS scale,avoiding pitfalls commonly observed with other approaches. 展开更多
关键词 Herbal HEPATOTOXICITY Herb INDUCED LIVER INJURY Herbs DRUG HEPATOTOXICITY DRUG INDUCED LIVER INJURY CAUSALITY assessment
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Fetal MRI Artifacts: Semi-Supervised Generative Adversarial Neural Network for Motion Artifacts Reducing in Fetal Magnetic Resonance Images
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作者 Ítalo Messias Félix Santos Gilson Antonio Giraldi +1 位作者 Heron Werner Junior Bruno Richard schulze 《Journal of Computer and Communications》 2024年第6期210-225,共16页
This study addresses challenges in fetal magnetic resonance imaging (MRI) related to motion artifacts, maternal respiration, and hardware limitations. To enhance MRI quality, we employ deep learning techniques, specif... This study addresses challenges in fetal magnetic resonance imaging (MRI) related to motion artifacts, maternal respiration, and hardware limitations. To enhance MRI quality, we employ deep learning techniques, specifically utilizing Cycle GAN. Synthetic pairs of images, simulating artifacts in fetal MRI, are generated to train the model. Our primary contribution is the use of Cycle GAN for fetal MRI restoration, augmented by artificially corrupted data. We compare three approaches (supervised Cycle GAN, Pix2Pix, and Mobile Unet) for artifact removal. Experimental results demonstrate that the proposed supervised Cycle GAN effectively removes artifacts while preserving image details, as validated through Structural Similarity Index Measure (SSIM) and normalized Mean Absolute Error (MAE). The method proves comparable to alternatives but avoids the generation of spurious regions, which is crucial for medical accuracy. 展开更多
关键词 Fetal MRI Artifacts Removal Deep Learning Image Processing Generative Adversarial Networks
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Wound-Induced Shoot-to-Root Relocation of JA-Ile Precursors Coordinates Arabidopsis Growth 被引量:8
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作者 Adina schulze Marlene Zimmer +4 位作者 Stefan Mielke Hagen Stellmach Charles WMelnyk Bettina Hause Debora Gasperini 《Molecular Plant》 SCIE CAS CSCD 2019年第10期1383-1394,共12页
Multicellular organisms rely on the movement of signaling molecules across cells,tissues,and organs to communicate among distal sites.In plants,localized leaf damage activates jasmonic acid(JA)-dependent transcription... Multicellular organisms rely on the movement of signaling molecules across cells,tissues,and organs to communicate among distal sites.In plants,localized leaf damage activates jasmonic acid(JA)-dependent transcriptional reprogramming in both harmed and unharmed tissues.Although it has been indicated that JA species can translocate from damaged into distal sites,the identity of the mobile compound(s),the tissues through which they translocate,and the effect of their relocation remain unknown.Here,we found that following shoot wounding,the relocation of endogenous jasmonates through the phloem is essential to initiate JA signaling and stunt growth in unharmed roots of Arabidopsis thaliana.By employing grafting experiments and hormone profiling,we uncovered that the hormone precursor cis-12-oxo-phytodienoic acid(OPDA)and its derivatives,but not the bioactive JA-Ile conjugate,translocate from wounded shoots into undamaged roots.Upon root relocation,the mobile precursors cooperatively regulated JA responses through their conversion into JA-Ile and JA signaling activation.Collectively,our findings demonstrate the existence of long-distance translocation of endogenous OPDA and its derivatives,which serve as mobile molecules to coordinate shoot-to-root responses,and highlight the importance of a controlled redistribution of hormone precursors among organs during plant stress acclimation. 展开更多
关键词 GRAFTING JASMONATE OPDA PHLOEM PHYTOHORMONE
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大别山超高压变质带层析地震调查 被引量:7
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作者 彭聪 姜枚 +3 位作者 宿和平 史大年 A.schulze T.Ryberg 《地质论评》 CAS CSCD 北大核心 2000年第3期288-294,共7页
1997年3月中德合作进行了大别山科学钻探选址区层析地震调查,研究结果揭示出大别山超高压变质带(UHP)地壳精细结构。郯庐断裂带近垂直延伸至Moho界面(可能更深),在Moho界面以上郯庐断裂带西侧大别山地壳物质没有迁移进入其东侧。在主测... 1997年3月中德合作进行了大别山科学钻探选址区层析地震调查,研究结果揭示出大别山超高压变质带(UHP)地壳精细结构。郯庐断裂带近垂直延伸至Moho界面(可能更深),在Moho界面以上郯庐断裂带西侧大别山地壳物质没有迁移进入其东侧。在主测线(横中至潜山镇)20km深度发现一个由西向东倾斜的强反射层,推测可能是一个大的滑脱层。超高压变质岩石(或地幔物质)可能由地幔深处通过郯庐断裂带再沿此滑脱层折返到地壳上部,经后期剥蚀出露地表。 展开更多
关键词 大别山 超高压变质带 郯庐断裂 地震层析成像
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高对映选择性环氧化物水解酶产生菌的筛选及特性研究 被引量:7
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作者 唐燕发 许建和 +2 位作者 武慧渊 叶勤 schulze Birgit 《微生物学通报》 CAS CSCD 北大核心 2001年第5期14-17,共4页
从土壤中分离的芽孢杆菌BacillusmegateriumECU1 0 0 1所产环氧化物水解酶能高对映选择性水解缩水甘油苯基醚 (对映选择率E值可达 47 8) ,当转化率为 5 5 9%时 ,剩余的 (S) 缩水甘油苯基醚的光学纯度 (对映体过量值 ,ee)可达 99 5 % ... 从土壤中分离的芽孢杆菌BacillusmegateriumECU1 0 0 1所产环氧化物水解酶能高对映选择性水解缩水甘油苯基醚 (对映选择率E值可达 47 8) ,当转化率为 5 5 9%时 ,剩余的 (S) 缩水甘油苯基醚的光学纯度 (对映体过量值 ,ee)可达 99 5 % ;当底物浓度提高到 60mmol/L时 ,光学纯 (S) 缩水甘油苯基醚的收率达到 2 5 6% 展开更多
关键词 缩水甘油苯基醚 手性环氧化物 巨大芽孢杆菌 环氧化物水解酶 菌株筛选 对映选择性 水解
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基于3-D图像的植物亏水胁迫萎蔫体态辨识方法 被引量:8
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作者 张慧娟 赵燕东 +3 位作者 孙宇瑞 王聪颖 蔡祥 schulze Lammers P 《农业机械学报》 EI CAS CSCD 北大核心 2011年第1期154-158,共5页
萎蔫现象是植物亏水胁迫环境下表现出的一种生命特征。为了定量辨识植株的萎蔫体态,在应用激光扫描装置快速获取植株3-D图像基础上,定义了4种萎蔫指数,即叶面卷曲统计指数、叶片形心的高斯曲率、基于形心切平面的叶尖投影以及叶片边缘... 萎蔫现象是植物亏水胁迫环境下表现出的一种生命特征。为了定量辨识植株的萎蔫体态,在应用激光扫描装置快速获取植株3-D图像基础上,定义了4种萎蔫指数,即叶面卷曲统计指数、叶片形心的高斯曲率、基于形心切平面的叶尖投影以及叶片边缘投影求和平均。实验方法将叶片萎蔫程度分为5个等级水平(LS1~LS5),通过逐一检验每种定义的萎蔫指数是否具有单调性得出可应用性结论。实验结果表明距离投影算法满足萎蔫指数的单调要求,尤其是叶片边缘投影求和平均萎蔫指数具有更好的鲁棒性。 展开更多
关键词 亏水胁迫 萎蔫指数 三维图像 形态辨识
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Testicular expression of survivin and human telomerase reverse transcriptase(hTERT)associated with spermatogenic function in infertile patients 被引量:8
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作者 Steffen Weikert Frank Christoph +5 位作者 Wolfgang schulze Hans Krause Carsten Kempkensteffen Martin Schostak Kurt Miller Mark Schrader 《Asian Journal of Andrology》 SCIE CAS CSCD 2006年第1期95-100,共6页
Aim: To characterize the coexpression of survivin, an inhibitor of apoptosis (IAF), and human telomerase reverse transcriptase (hTERT) in human testes with varying spermatogenic function. Methods: Transcript lev... Aim: To characterize the coexpression of survivin, an inhibitor of apoptosis (IAF), and human telomerase reverse transcriptase (hTERT) in human testes with varying spermatogenic function. Methods: Transcript levels of survivin mRNA and hTERT mRNA were determined in normal testes (n = 11) and testes with defective spermatogenesis (n = 28) using real-time reverse-transcription polymerase chain reaction (RT-PCR). The histological work-up was performed according to a modified Johnsen score. Results: Expressions of both survivin and hTERT were highest at median levels of 96.8 and 709 in normal spermatogenesis and dropped to 53.3 and 534 in testes with postmeiotic spermatogenic arrest (n = 10). In severe spermatogenic failure (n = 18), survivin expression was lacking in most specimens (n = 16), whereas at least low levels of testicular hTERT expression were largely detectable with a normalized expression of 73 in premeiotic spermatogenic arrest (n = 7) and 45 in patients with Sertoli cell-only syndrome (SCOS) (n = 3). Both survivin and hTERT expressions increased with a progressing Johnsen score (P for trend = 0.001). Conclusion: Although both survivin and hTERT are correlated with spermatogenic function, they show different expression patterns in testes of infertile patients. These findings substantiate results from studies in the rodent testis suggesting a predominant expression of survivin in meiotically dividing germ cells. (Asian J Andro12006 Jan; 8: 95-100) 展开更多
关键词 SURVIVIN human telomerase reverse transcriptase apoptosis AZOOSPERMIA male infertility SPERMATOGENESIS
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