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面向21世纪的卒中新定义:美国心脏病学会和美国卒中学会声明 被引量:206
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作者 俞羚 董荃 +25 位作者 宋叶平 江静雯 李卉 刘亮贤 苏爱萍 李焰生 Sacco RL Kasner SE Broderick JP Caplan LR Connors JJ Culebras A Elkind MS George MG Hamdan AD Higashida RT Hoh BL Janis LS Kase CS Kleindorfer DO Lee JM Moseley ME Peterson ED Turan TN Valderrama al Vinters HV 《神经病学与神经康复学杂志》 2013年第2期105-120,共16页
尽管脑血管病有着全球性影响且对其病理生理学的认识有了很多进步,但是"卒中"这一术语在临床实践、临床研究或公共卫生评估中的定义却不一致。传统的定义依据于临床,却没有考虑到科学技术的进步。美国心脏协会(AHA)和美国卒... 尽管脑血管病有着全球性影响且对其病理生理学的认识有了很多进步,但是"卒中"这一术语在临床实践、临床研究或公共卫生评估中的定义却不一致。传统的定义依据于临床,却没有考虑到科学技术的进步。美国心脏协会(AHA)和美国卒中协会(ASA)卒中分会组织了写作小组,为21世纪卒中新定义撰写专家共识性声明。中枢神经系统(CNS)梗死,指由缺血所导致的脑、脊髓或视网膜的细胞死亡,是基于持续性损害的神经病理学、神经影像学和(或)临床证据。CNS梗死表现为一个临床谱:缺血性卒中特指伴有明显症状的CNS梗死,而静息性梗死根据定义指未引起已知的症状的梗死。卒中也还包括脑出血和蛛网膜下腔出血。新定义的卒中结合了临床和组织学标准,可被用于实践、研究和公共卫生评估。 展开更多
关键词 美国心脏协会科学声明 脑出血 脑梗死 卒中 蛛网膜下腔出血 短暂性缺血发作
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我国胆石病十年来的变迁 被引量:155
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作者 Zhu Xueguang Zhang Shengduo +1 位作者 HuangZhiqiang et al. People′s Hospital,Beijing Medical U-niversity,Beijing100044. 《中华外科杂志》 CAS CSCD 北大核心 1995年第11期652-658,共7页
作者报道了由全国胆道外科学组组织的来自7个省市、33所医院3911例胆结石手术病例的第二次全国临床调查资料并与十年前首次调查的结果(中华外科杂志1987,25:321~329)比较。调查证实:胆石病仍是我国普外临床的... 作者报道了由全国胆道外科学组组织的来自7个省市、33所医院3911例胆结石手术病例的第二次全国临床调查资料并与十年前首次调查的结果(中华外科杂志1987,25:321~329)比较。调查证实:胆石病仍是我国普外临床的多发病,约占同时期住院患者的11.5%;多见于50岁以上的女性;女:男约2.57:1。约80%的单一部位结石分布于胆囊,以胆固醇类结石为主;而以胆色素类为主的胆管结石仅占10%。与十年前相比,胆囊:胆管结石从1.5:1上升至7.36:1;胆固醇:胆色素结石从1.4:1升至3.4:1。调查还发现:上述关于结石类型及结石部位上的变化与近十年来胆道蛔虫及胆道感染率的显著下降及饮食结构的变化有关。 展开更多
关键词 胆结石 胆囊 胆管 胆固醇 胆色素 流行病学
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晚新生代岷江下蚀速率及其对青藏高原东缘山脉隆升机制和形成时限的定量约束 被引量:72
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作者 李勇 曹叔尤 +2 位作者 周荣军 al DENSMORE M A ELLIS 《地质学报》 EI CAS CSCD 北大核心 2005年第1期28-37,共10页
青藏高原东缘具有青藏高原地貌、龙门山高山地貌和山前冲积平原三个一级地貌单元 ,本文以岷江作为切入点 ,研究了该地区河流下蚀速率与山脉的隆升作用之间的相互关系。在建立岷江阶地序列的基础上 ,利用阶地高程和热释光年代学测年资料... 青藏高原东缘具有青藏高原地貌、龙门山高山地貌和山前冲积平原三个一级地貌单元 ,本文以岷江作为切入点 ,研究了该地区河流下蚀速率与山脉的隆升作用之间的相互关系。在建立岷江阶地序列的基础上 ,利用阶地高程和热释光年代学测年资料分别定量计算了岷江在川西高原、龙门山和成都盆地的下蚀速率 ,结果表明岷江各河段的下蚀速率明显不同 ,分别为 1.0 7~ 1.6 1mm / a、1.81m m/ a和 0 .5 9mm / a;在龙门山地区岷江的下蚀速率最高 ,约为川西高原地区的 1.5倍 ,约为成都平原地区的 3倍 ;而同一河段不同时期岷江的下蚀速率基本是连续的 ,具有很好的线性关系 ,可作为该河段整个河谷的下蚀速率。基于龙门山的表面隆升速率 (0 .3~ 0 .4 mm / a) ,在约束局部侵蚀基准面和气候变化对阶地形成的控制作用的基础上 ,本文建立了青藏高原东缘岷江下蚀速率与龙门山表面隆升速率之间的线性关系 ,结果表明河流下蚀速率约为山脉表面隆升速率的 5倍。根据龙门山表面在隆升速率和下切速率等方面均大于川西高原 ,并结合龙门山活动构造以走滑作用为主 ,笔者认为青藏高原东缘的边缘山脉以剥蚀隆升为主 ,兼有构造隆升作用。最后 ,根据岷江最大切割深度所需的时间 (3.4 8Ma)和成都盆地最古老的岷江冲积扇大邑砾岩的时间 (3.6 展开更多
关键词 山脉隆升 龙门山 青藏高原东缘 阶地 成都盆地 升速 晚新生代 速率 走滑作用 砾岩
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Severe acute pancreatitis: Pathogenetic aspects and prognostic factors 被引量:69
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作者 Ibrahim A al Mofleh 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第5期675-684,共10页
Approximately 20% of patients with acute pancreatitis develop a severe disease associated with complications and high risk of mortality. The purpose of this study is to review pathogenesis and prognostic factors of se... Approximately 20% of patients with acute pancreatitis develop a severe disease associated with complications and high risk of mortality. The purpose of this study is to review pathogenesis and prognostic factors of severe acute pancreatitis (SAP). An extensive medline search was undertaken with focusing on pathogenesis, complications and prognostic evaluation of SAP. Cytokines and other inflammatory markers play a major role in the pathogenesis and course of SAP and can be used as prognostic markers in its early phase. Other markers such as simple prognostic scores have been found to be as e^ective as multifactorial scoring systems (MFSS) at 48 h with the advantage of simplicity, efficacy, low cost, accuracy and early prediction of SAP. Recently, several laboratory markers including hematocrit, blood urea nitrogen (BUN), creatinine, matrix metalloproteinase-9 (MMP-9) and serum amyloid A (SAA) have been used as early predictors of severity within the first 24 h. The last few years have witnessed a tremendous progress in understanding the pathogenesis and predicting the outcome of SAP. In this review we classified the prognostic markers into predictors of severity, pancreatic necrosis (PN), infected PN (IPN) and mortality. 展开更多
关键词 Acute pancreatitis PATHOGENESIS PREDICTION SEVERITY NECROSIS Infected necrosis MORTALITY
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改进Faster R-CNN的田间苦瓜叶部病害检测 被引量:56
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作者 李就好 林乐坚 +1 位作者 田凯 al Aasmi alaa 《农业工程学报》 EI CAS CSCD 北大核心 2020年第12期179-185,共7页
为实现在自然环境条件下对苦瓜叶部病害的目标检测,该研究提出了一种基于改进的更快速区域卷积神经网络(Faster Region with Convolutional Neural Network Features,Faster R-CNN)的苦瓜叶部病害目标检测方法。Faster R-CNN以残差结构... 为实现在自然环境条件下对苦瓜叶部病害的目标检测,该研究提出了一种基于改进的更快速区域卷积神经网络(Faster Region with Convolutional Neural Network Features,Faster R-CNN)的苦瓜叶部病害目标检测方法。Faster R-CNN以残差结构卷积神经网络ResNet-50作为该次试验的特征提取网络,将其所得特征图输入到区域建议网络提取区域建议框,并且结合苦瓜叶部病害尺寸小的特点,对原始的Faster R-CNN进行修改,增加区域建议框的尺寸个数,并在ResNet-50的基础下融入了特征金字塔网络(Feature Pyramid Networks,FPN)。结果表明,该方法训练所得的深度学习网络模型具有良好的鲁棒性,平均精度均值(Mean Average Precision,MAP)值为78.85%;融入特征金字塔网络后,所得模型的平均精度均值为86.39%,提高了7.54%,苦瓜健康叶片、白粉病、灰斑病、蔓枯病、斑点病的平均精确率(Average Precision,AP)分别为89.24%、81.48%、83.31%、88.62%和89.28%,在灰斑病检测精度上比之前可提高了16.56%,每幅图像的检测时间达0.322 s,保证检测的实时性。该方法对复杂的自然环境下的苦瓜叶部病害检测具有较好的鲁棒性和较高的精度,对瓜果类疾病预防有重要的研究意义。 展开更多
关键词 卷积神经网络 机器视觉 病害 自动检测 Faster R-CNN 苦瓜 特征金字塔网络
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全国第二次冠心病介入性治疗病例注册登记资料分析 被引量:50
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作者 Section of Interventional Cardiology, Chinese Society of Cardiology, Chinese Medical Association, et al. (Correspondent: GAO Runlin. Fu Wai Hospital, PUMC & CAMS, Beijing 100037, China) 《中华心血管病杂志》 CAS CSCD 北大核心 2000年第1期10-13,共4页
目的 分析 1997年和 1998年我国冠心病介入性治疗发展趋势。方法 采用填写统一发放的表格的方法 ,收集 1997、1998两年各医院冠心病介入性治疗病例资料 ,进行回顾性分析。结果共注册经皮冠状动脉腔内成形术 (PTCA)病例总数 872 5例 ,... 目的 分析 1997年和 1998年我国冠心病介入性治疗发展趋势。方法 采用填写统一发放的表格的方法 ,收集 1997、1998两年各医院冠心病介入性治疗病例资料 ,进行回顾性分析。结果共注册经皮冠状动脉腔内成形术 (PTCA)病例总数 872 5例 ,来自全国范围内 75所医院 ,总成功数 83 69例 (95 9% )。其中 1997年 3 74 0例 ,成功 3 5 5 3例 (95 0 % ) ;1998年 4 985例 ,成功 4 816例 (96 6% )。共扩张病变 10 2 18处 ,成功 965 0处 ,病变成功率为 94 4 %。急性心肌梗死 (AMI)急诊PTCA 10 4 5例 ,成功10 0 1例 (95 8% )。全组患者发生重要并发症 95 9例 (11 0 % ) ,包括死亡 3 2例 (0 3 7% )。冠状动脉支架置入术 63 2 9例 ,共置入支架 774 8只 ,其中左冠状动脉主干置入支架 86只 (占 1 1% )。置入成功7677只 (99 1% )。发生重要并发症 5 10例 (8 1% ) ,包括死亡 2 5例 (0 4 0 % )。全部患者服用噻氯匹啶 ,其中 13 8例 (1 8% )发生粒细胞减少症。另外 ,注册登记冠状动脉斑块旋磨术 93例 (94支血管 ) ,成功率为 93 6%。结论  1997年和 1998年我国冠心病介入治疗例数有大幅度增长 ,两年内完成病例数远远超过过去 12年积累病例总数 ,成功率较过去有增加趋势 ,但地区间及医院间发展仍很不平衡。 展开更多
关键词 冠心病 血管成形术 支架置入术 PTCA 介入疗法
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China's wetland change (1990-2000) determined by remote sensing 被引量:30
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作者 Peng Gong ZhenGuo Niu +8 位作者 Xiao Cheng KuiYi Zhao DeMin Zhou JianHong Guo Lu Liang XiaoFeng Wang DanDan Li HuaBing Huang et al. 《Science China Earth Sciences》 SCIE EI CAS 2010年第7期1036-1042,共7页
Two wetland maps for the entire China have been produced based on Landsat data acquired around 1990 and 2000. Wetlands in China have been divided into 3 broad categories with 15 sub-categories except rice fields. In 1... Two wetland maps for the entire China have been produced based on Landsat data acquired around 1990 and 2000. Wetlands in China have been divided into 3 broad categories with 15 sub-categories except rice fields. In 1990, the total wetland area in China was 355208 km2 whereas in 2000 it dropped to 304849 km2 with a net loss of 50360 km2. During an approximate 10-year period, inland wetland reduced from 318326 to 257922 km2, coastal wetland dropped from 14335 to 12015 km2, while artificial wetland increased from 22546 to 34911 km2. The greatest natural wetland loss occurred in Heilongjiang, Inner Mon- golia, and Jilin with a total loss of over 57000 km2 of wetland. In western China, over 13000 km2 of wetlands were newly formed in Xinjiang, Tibet, and Qinghai. About 12000 km2 of artificial wetlands were also added for fish farm and reservoir constructions. The newly formed wetlands in western China were caused primarily by climate warming over that region whereas the newly created artificial wetlands were caused by economic developments. China’s wetland loss is caused mainly by human activities. 展开更多
关键词 WETLAND MAPPING NATURAL WETLAND LOSS artificial WETLAND INCREASE
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中日竞走运动员高原训练的生理机能及运动能力的研究 被引量:23
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作者 Li Hua, et al. (Qinghai Institute of Sports Science, Xining, China 810000)J. Aoki, et al(University of Zuntendo, Japan) Sino-Japanese Research Group for altitude Training 《体育科学》 CSSCI 北大核心 1995年第5期30-39,共10页
10名世居高原(2260米)的中国竞走运动员和10名居平原(10m)的日本竞走运动员在多巴(2366米),作4周高原训练。高原训练后期与前期、高原与平原相比,观察到有益的代偿性改变。如运动后的恢复心率(1分至1分10秒)下降加快(13次/分降至105次/... 10名世居高原(2260米)的中国竞走运动员和10名居平原(10m)的日本竞走运动员在多巴(2366米),作4周高原训练。高原训练后期与前期、高原与平原相比,观察到有益的代偿性改变。如运动后的恢复心率(1分至1分10秒)下降加快(13次/分降至105次/分);在负荷心率相近条件下,步速加快(3.61m/s增至3.80m/s),无氧阈速度加快(中方,3.01增至3.22;日方,2.78增至3.30m/s);左室功能有改善(SV:日男由85.4→98.1ml;C1:中男由3.10→3.28L/m^2·min);乳酸—速度曲线右移(日男由7.2→5.4mM,中男由6.2→5.6mM);缓冲系统的能力有改善(女子:BE,—4.7→0.2mM;HCO_3,18.6→25.2mM);肺通气功能有所加强(MVV:中方,108.6→113.5L/min,日方,139.8→146.6L/min)。高原训练后,下平原比赛,中日各有8名队员提高了本人最好成绩。 展开更多
关键词 高原训练 竞走 心肺功能 血乳酸 递增运动试验
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481例急性早幼粒细胞白血病完全缓解后随访报告 被引量:24
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作者 Sun Guanlin Zhou Rongfu +1 位作者 Wu Wen et al(The National Cooperarive Group of Leukemia Treatment with ATRA, 200025) 《中华血液学杂志》 CAS CSCD 北大核心 1994年第8期411-413,共3页
481例急性早幼粒细胞白血病经全反式维甲酸诱导达完全缓解后,分别接受4种不同的缓解后治疗方案,经随访2~87(中位数25)个月,从Kaplan-Meier生存曲线与生存概率比较,以化疗与维甲酸交替治疗组疗效较好。3年... 481例急性早幼粒细胞白血病经全反式维甲酸诱导达完全缓解后,分别接受4种不同的缓解后治疗方案,经随访2~87(中位数25)个月,从Kaplan-Meier生存曲线与生存概率比较,以化疗与维甲酸交替治疗组疗效较好。3年生存概率为0.768±0.062。持续单用维甲酸维持组疗效最差。 展开更多
关键词 维甲酸 白血病 诱导分化 治疗
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高白细胞性急性白血病 244 例临床分析 被引量:27
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作者 Shanghai Leukemia Cooperation Group Wang Xiaoqin, Lin Guowei, Wang Jun, et al. Shanghai Huashan Hospital, Shanghai 200040 《中华内科杂志》 CAS CSCD 北大核心 1997年第8期532-535,共4页
为了解高白细胞性急性白血病(HAL)的临床规律和预后因素。对244例HAL和同期非HAL进行回顾性对照分析。结果显示:发现HAL构成比为8.5%,HAL中急性淋巴细胞白血病(ALL)较多,在急性髓细胞白血病(AML)... 为了解高白细胞性急性白血病(HAL)的临床规律和预后因素。对244例HAL和同期非HAL进行回顾性对照分析。结果显示:发现HAL构成比为8.5%,HAL中急性淋巴细胞白血病(ALL)较多,在急性髓细胞白血病(AML)中M5占的比例最多,为40.5%。HAL发病时肝、脾、淋巴结肿大,DIC,中枢神经系统白血病(CNSL)较非HAL为多。完全缓解(CR)率为41.4%,低于非HAL的54.2%,早期病死率是23.8%。早期死亡的主要原因是颅内出血,占50%。早期死亡的高危因素有发病时Hb≤40g/L,血小板≤30×109/L,DIC,感染,CNSL。结果显示:HAL完全缓解率低,早期死亡率高,预后差,特别是HAL-AML的早期死亡率明显高于HAL-ALL,要重视其早期处理。 展开更多
关键词 白血病 白细胞增多 诊断 治疗 临床分析
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Effects of heat shock on change of HSC70/HSP68,acid and alkaline phosphatases before and after rat partial hepatectomy 被引量:27
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作者 Lu al Xu CS 《World Journal of Gastroenterology》 SCIE CAS CSCD 2000年第5期730-733,共4页
INTRODUCTIONOnly the liver has the great capability ofregeneration in mammal.Few hepatocytes are inthe phase of division in the normal liver of an adultmammal (including human beings),but theremaining hepatocytes can ... INTRODUCTIONOnly the liver has the great capability ofregeneration in mammal.Few hepatocytes are inthe phase of division in the normal liver of an adultmammal (including human beings),but theremaining hepatocytes can be induced to proliferatequickly by partial hepatectomy (PH),and,to somedegree,they stop dividing and re-differentiate intocells functioning as hepatocytes.This shows 展开更多
关键词 partial hepatectomy(PH) liver regeneration CONSERVED HEAT-SHOCK PROTEIN 70/induced HEAT-SHOCK PROTEIN 68(HSCT0/HSP68) ACID PHOSPHATASES alkaline PHOSPHATASES
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Giant cavernous liver hemangiomas: is it the time to change the size categories? 被引量:25
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作者 isidoro di carlo renol koshy +3 位作者 saif al mudares annalisa ardiri gaetano bertino adriana toro 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2016年第1期21-29,共9页
BACKGROUND: Four different sizes (4, 5, 8 and 10 cm in diameter) can be found in the literature to categorize a liver hemangioma as giant. The present review aims to clarify the appropriateness of the size category... BACKGROUND: Four different sizes (4, 5, 8 and 10 cm in diameter) can be found in the literature to categorize a liver hemangioma as giant. The present review aims to clarify the appropriateness of the size category "giant" for liver heman- gioma. DATA SOURCES: We reviewed the reports on the categoriza- tion of hemangioma published between 1970 and 2014. The number of hemangiomas, size criteria, mean and range of hemangioma sizes, and number of asymptomatic and symp- tomatic patients were investigated in patients aged over 18 years. Liver hemangiomas were divided into four groups: 〈5.0 cm, 5.0-9.9 cm, 10.0-14.9 cm and 〉15.0 cm in diameter. Inclu- sion criteria were noted in 34 articles involving 1972 (43.0%) hemangiomas (〉4.0 cm). RESULTS: The patients were divided into the following groups: 154 patients (30.0%) with hemangiomas less than 5.0 cm in diameter (small), 182 (35.5%) between 5.0 cm and 9.9 cm (large), 75 (14.6%) between 10.0 and 14.9 cm (giant), and 102 (19.9%) more than 15.0 cm (enormous). There were 786 (39.9%) asymptomatic patients and 791 (40.1%) symptomatic patients. Indications for surgery related to symptoms were reported in only 75 (3.8%) patients. Operations including 137 non-anatomical resection (12.9%) and 469 enudeation (44.1%) were undearly related to size and symptoms.CONCLUSIONS: The term "giant" seems to be justified for liver hemangiomas with a diameter of 10 cm. Hemangiomas categorized as "giant" are not indicated for surgery. Surgery should be performed only when other symptoms are apparent. 展开更多
关键词 giant hemangioma cavernous hemangioma liver hemangioma
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Bartter and Gitelman syndromes:Spectrum of clinical manifestations caused by different mutations 被引量:25
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作者 Amar al Shibli Hassib Narchi 《World Journal of Methodology》 2015年第2期55-61,共7页
Bartter and Gitelman syndromes(BS and GS) are inherited disorders resulting in defects in renal tubularhandling of sodium,potassium and chloride.Previously considered as genotypic and phenotypic heterogeneous diseases... Bartter and Gitelman syndromes(BS and GS) are inherited disorders resulting in defects in renal tubularhandling of sodium,potassium and chloride.Previously considered as genotypic and phenotypic heterogeneous diseases,recent evidence suggests that they constitute a spectrum of disease caused by different genetic mutations with the molecular defects of chloride reabsorption originating at different sites of the nephron in each condition.Although they share some characteristic metabolic abnormalities such as hypokalemia,metabolic alkalosis,hyperplasia of the juxtaglomerular apparatus with hyperreninemia,hyperaldosteronism,the clinical and laboratory manifestations may not always allow distinction between them.Diuretics tests,measuring the changes in urinary fractional excretion of chloride from baseline after administration of either hydrochlorothiazide or furosemide show very little change(< 2.3%) in the fractional excretion of chloride from baseline in GS when compared with BS,except when BS is associated with KCNJ1 mutations where a good response to both diuretics exists.The diuretic test is not recommended for infants or young children with suspected BS because of a higher risk of volume depletion in such children.Clinical symptoms and biochemical markers of GS and classic form of BS(type III) may overlap and thus genetic analysis may specify the real cause of symptoms.However,although genetic analysis is available,its use remains limited because of limited availability,large gene dimensions,lack of hot-spot mutations,heavy workup time and costs involved.Furthermore,considerable overlap exists between the different genotypes and phenotypes.Although BS and GS usually have distinct presentations and are associated with specific gene mutations,there remains considerable overlap between their phenotypes and genotypes.Thus,they are better described as a spectrum of clinical manifestations caused by different gene mutations. 展开更多
关键词 Gitelman SYNDROME Bartter SYNDROME POTASSIUM Chloride Magnesium METABOLIC ALKALOSIS GENETICS
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Toxic tau: structural origins of tau aggregation in Alzheimer’s disease 被引量:24
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作者 Abdullah al Mamun Md.Sahab Uddin +1 位作者 Bijo Mathew Ghulam Md Ashraf 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第8期1417-1420,共4页
Alzheimer’s disease is characterized by the extracellular accumulation of the amyloidβin the form of amyloid plaques and the intracellular deposition of the microtubule-associated protein tau in the form of neurofib... Alzheimer’s disease is characterized by the extracellular accumulation of the amyloidβin the form of amyloid plaques and the intracellular deposition of the microtubule-associated protein tau in the form of neurofibrillary tangles.Most of the Alzheimer’s drugs targeting amyloidβhave been failed in clinical trials.Particularly,tau pathology connects greatly in the pathogenesis of Alzheimer’s disease.Tau protein enhances the stabilization of microtubules that leads to the appropriate function of the neuron.Changes in the quantity or the conformation of tau protein could affect its function as a microtubules stabilizer and some of the processes wherein it is involved.The molecular mechanisms leading to the accumulation of tau are principally signified by numerous posttranslational modifications that change its conformation and structural state.Therefore,aberrant phosphorylation,as well as truncation of tau protein,has come into focus as significant mechanisms that make tau protein in a pathological entity.Furthermore,the shape-shifting nature of tau advocates to comprehend the progression of Alzheimer’s disease precisely.In this review,we emphasize the recent studies about the toxic and shape-shifting nature of tau in the pathogenesis of Alzheimer’s disease. 展开更多
关键词 Alzheimer’s disease neurofibrillary tangles shape-shifting nature of tau tau aggregation toxic tau
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性别和社会发展对中国大学生男性观念的影响 被引量:17
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作者 吴荣先 Ronald F.Levant al Sellers 《心理科学》 CSSCI CSCD 北大核心 2001年第3期365-366,共2页
关键词 男性 性别 性观念 性关系 影响 男子 个性 文化信念 内化 中国大学生
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空气质量模型及参数选用导则 被引量:18
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作者 Lin Hong(Chinese Research Academy of Environmental Sciences, Beijing 100012)Sang Jianguo(Beijing University,Beijing 100871)Xu Dahai et al.(The Research Academy of Meteorology, Beijing 100086) 《环境科学研究》 EI CAS CSCD 1993年第4期24-33,共10页
本研究是为了在大气污染物浓度估算中提供一个可以接受的技术分析的共同尺度,将所需用的空气质量模式分为三个等级。第一级模式作为在制定大气环境管理的法规和政策时主要应用的模式。第二、三级模式作为研究级模式。本文详细介绍了第... 本研究是为了在大气污染物浓度估算中提供一个可以接受的技术分析的共同尺度,将所需用的空气质量模式分为三个等级。第一级模式作为在制定大气环境管理的法规和政策时主要应用的模式。第二、三级模式作为研究级模式。本文详细介绍了第一级模式的主要应用原则,简要介绍了第二、三级模式。 展开更多
关键词 扩散 转化 沉降 空气 质量模型
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Review of surfactant-assisted chemical enhanced oil recovery for carbonate reservoirs: challenges and future perspectives 被引量:19
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作者 Sreela Pal M.Mushtaq +1 位作者 Fawzi Banat ali M.al Sumaiti 《Petroleum Science》 SCIE CAS CSCD 2018年第1期77-102,共26页
A significant fraction of the conventional oil reserves globally is in carbonate formations which contain a substantial amount of residual oil. Since primary and secondary recovery methods fail to yield above 20%-40%o... A significant fraction of the conventional oil reserves globally is in carbonate formations which contain a substantial amount of residual oil. Since primary and secondary recovery methods fail to yield above 20%-40%of original oil in place from these reserves, the need for enhanced oil recovery(EOR) techniques for incremental oil recovery has become imperative. With the challenges presented by the highly heterogeneous carbonate rocks,evaluation of tertiary-stage recovery techniques including chemical EOR(c EOR) has been a high priority for researchers and oil producers. In this review, the latest developments in the surfactant-based c EOR techniques applied in carbonate formations are discussed, contemplating the future direction of existing methodologies. In connection with this, the characteristics of heterogeneous carbonate reservoirs are outlined. Detailed discussion on surfactant-led oil recovery mechanisms and related processes, such as wettability alteration, interfacial tension reduction, microemulsion phase behavior, surfactant adsorption and mitigation, and foams and their applications is presented. Laboratory experiments, as well as field study data obtained using several surfactants, are also included.This extensive discussion on the subject aims to help researchers and professionals in the field to understand the current situation and plan future enterprises accordingly. 展开更多
关键词 Oil reserves Original oil in place Carbonateformations SURFACTANTS Chemical enhanced oil recovery
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Support Vector Machine and Random Forest Modeling for Intrusion Detection System (IDS) 被引量:19
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作者 Md. al Mehedi Hasan Mohammed Nasser +1 位作者 Biprodip Pal Shamim Ahmad 《Journal of Intelligent Learning Systems and Applications》 2014年第1期45-52,共8页
The success of any Intrusion Detection System (IDS) is a complicated problem due to its nonlinearity and the quantitative or qualitative network traffic data stream with many features. To get rid of this problem, seve... The success of any Intrusion Detection System (IDS) is a complicated problem due to its nonlinearity and the quantitative or qualitative network traffic data stream with many features. To get rid of this problem, several types of intrusion detection methods have been proposed and shown different levels of accuracy. This is why the choice of the effective and robust method for IDS is very important topic in information security. In this work, we have built two models for the classification purpose. One is based on Support Vector Machines (SVM) and the other is Random Forests (RF). Experimental results show that either classifier is effective. SVM is slightly more accurate, but more expensive in terms of time. RF produces similar accuracy in a much faster manner if given modeling parameters. These classifiers can contribute to an IDS system as one source of analysis and increase its accuracy. In this paper, KDD’99 Dataset is used and find out which one is the best intrusion detector for this dataset. Statistical analysis on KDD’99 dataset found important issues which highly affect the performance of evaluated systems and results in a very poor evaluation of anomaly detection approaches. The most important deficiency in the KDD’99 dataset is the huge number of redundant records. To solve these issues, we have developed a new dataset, KDD99Train+ and KDD99Test+, which does not include any redundant records in the train set as well as in the test set, so the classifiers will not be biased towards more frequent records. The numbers of records in the train and test sets are now reasonable, which make it affordable to run the experiments on the complete set without the need to randomly select a small portion. The findings of this paper will be very useful to use SVM and RF in a more meaningful way in order to maximize the performance rate and minimize the false negative rate. 展开更多
关键词 INTRUSION Detection KDD’99 SVM KERNEL Random FOREST
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Safety and efficacy of ultrasound ciliary plasty as a primary intervention in glaucoma patients 被引量:18
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作者 Magda A.Torky Yousif A al Zafiri +3 位作者 Sherein M.Hagras Abeer M.Khattab Rania M.Bassiouny Tharwat H.Mokbel 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2019年第4期597-602,共6页
AIM: To evaluate the safety and the efficacy of the ultrasound ciliary plasty(UCP) on the intraocular pressure(IOP) control in glaucomatous eyes without previous glaucoma surgery.METHODS: A retrospective study include... AIM: To evaluate the safety and the efficacy of the ultrasound ciliary plasty(UCP) on the intraocular pressure(IOP) control in glaucomatous eyes without previous glaucoma surgery.METHODS: A retrospective study included patients with primary and secondary glaucoma who underwent UCP in Dar Al Shifa Hospital, Kuwait between January 2017 to June 2018. High-intensity focused ultrasound procedures were performed under peribulbar anesthesia using the 2^(nd) generation probe with 8 s duration of each of the 6 shots. Complete ophthalmologic examinations were scheduled pre-treatment, and at 1 d, 1 wk, 1, 3, 6 and 12 mo posttreatment. Primary outcomes were the IOP reduction and success rates at 12 mo, while the secondary outcomes were the occurrence of vision threatening complications and visual acuity.RESULTS: The records of 62 eyes of 62 patients were analyzed with mean age of 63.8 y(67.7% males). There was statistically significant reduction in the mean IOP from 35.2±8.3 mm Hg before treatment to 20.6±8.7 mm Hg at 12^(th) month(P<0.0005) with a mean percentage IOP reduction of 42.3% with significant reduction in the mean number of antiglaucomatous drugs from 3.2±0.4 before treatment to 2.1±1.02 at 12 mo(P<0.0005). Qualified success was achieved in 77.4% of eyes at 12 mo. No major intra-or posttreatment complications were reported.CONCLUSION: Second-generation UCP prove to be effective in reducing IOP in naive glaucoma patients with lower success rates in cases of neovascular and uveitic glaucomas. 展开更多
关键词 ULTRASOUND CILIARY PLASTY GLAUCOMA INTRAOCULAR pressure
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外用人α1型基因工程干扰素治疗慢性宫颈炎673例疗效观察 被引量:17
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作者 Wang Dawan, et al Beijing Obstetrics and Genecology Hospital, Beijing 《中国免疫学杂志》 CAS CSCD 北大核心 1990年第1期21-24,共4页
1988年8月至1989年1月,本协作组使用长春生研所研制成功的二种不同剂量外用人α1型基因工程干扰素1×10~5IU/ml及1×10~6IU/ml治疗慢性宫颈炎673例,在一疗程后总有效率达84.3%及86.6%,较对照组卡那霉素及妇炎灵的66.3%及62.9%为... 1988年8月至1989年1月,本协作组使用长春生研所研制成功的二种不同剂量外用人α1型基因工程干扰素1×10~5IU/ml及1×10~6IU/ml治疗慢性宫颈炎673例,在一疗程后总有效率达84.3%及86.6%,较对照组卡那霉素及妇炎灵的66.3%及62.9%为高(P<0.005)。停药6个月后,干扰素治疗组总有效率上升至90.1%及95.7%,疗效仍高于卡那霉素组的69.5%(P<0.05)。对宫颈糜烂病例宫颈局部作拭子标本197份进行HPV—16DNA分子杂交,阳性率达41.6%,其中经干扰素治疗166例,其治疗前后的阳性率分别为41.6%及17.5%,说明干扰素对HPV—16有一定的抑制作用。推测它有可能是一种阻断宫颈癌发生的方法。 展开更多
关键词 基因工程 干扰素 宫颈炎
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