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Restoration or Rehabilitation of the Faleme River Affected by Mining Activities: What Methods?
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作者 Mor Diop Ibrahima Mall +3 位作者 Elhadji Mamadou Sonko Tidiane Diop Birane Niane Cheikh Mbow 《Journal of Water Resource and Protection》 CAS 2024年第4期233-263,共31页
The Faleme River, a West Africa long transboundary stream (625 km) and abundant flow (>1100 million m<sup>3</sup>) is affected by severe erosion because of mining activities that takes place throughout ... The Faleme River, a West Africa long transboundary stream (625 km) and abundant flow (>1100 million m<sup>3</sup>) is affected by severe erosion because of mining activities that takes place throughout the riverbed. To preserve this important watercourse and ensure the sustainability of its services, selecting and implementing appropriates restorations techniques is vital. In this context, the purpose of this paper was to present an overview of the actions and techniques that can be implemented for the restoration/rehabilitation of the Faleme. The methodological approach includes field investigation, water sampling, literature review with cases studies and SWOT analysis of the four methods presented: river dredging, constructed wetlands, floating treatment wetlands and chemical precipitation (coagulation and flocculation). The study confirmed the pollution of the river by suspended solids (TSS > 1100 mg/L) and heavy metals such as iron, zinc, aluminium, and arsenic. For the restoration methods, it was illustrated through description of their mode of operation and through some case studies presented, that all the four methods have proven their effectiveness in treating rivers but have differences in their costs, their sustainability (detrimental to living organisms or causing a second pollution) and social acceptance. They also have weaknesses and issues that must be addressed to ensure success of rehabilitation. For the case of the Faleme river, after analysis, floating treatment wetlands are highly recommended for their low cost, good removal efficiency if the vulnerability of the raft and buoyancy to strong waves and flow is under control. 展开更多
关键词 Faleme River River Restoration Constructed Wetlands DREDGING Floating Treatment Wetlands COAGULATION-FLOCCULATION
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Integrated Machine Learning and Deep Learning Models for Cardiovascular Disease Risk Prediction: A Comprehensive Comparative Study
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作者 Shadman Mahmood Khan Pathan Sakan Binte Imran 《Journal of Intelligent Learning Systems and Applications》 2024年第1期12-22,共11页
Cardiovascular Diseases (CVDs) pose a significant global health challenge, necessitating accurate risk prediction for effective preventive measures. This comprehensive comparative study explores the performance of tra... Cardiovascular Diseases (CVDs) pose a significant global health challenge, necessitating accurate risk prediction for effective preventive measures. This comprehensive comparative study explores the performance of traditional Machine Learning (ML) and Deep Learning (DL) models in predicting CVD risk, utilizing a meticulously curated dataset derived from health records. Rigorous preprocessing, including normalization and outlier removal, enhances model robustness. Diverse ML models (Logistic Regression, Random Forest, Support Vector Machine, K-Nearest Neighbor, Decision Tree, and Gradient Boosting) are compared with a Long Short-Term Memory (LSTM) neural network for DL. Evaluation metrics include accuracy, ROC AUC, computation time, and memory usage. Results identify the Gradient Boosting Classifier and LSTM as top performers, demonstrating high accuracy and ROC AUC scores. Comparative analyses highlight model strengths and limitations, contributing valuable insights for optimizing predictive strategies. This study advances predictive analytics for cardiovascular health, with implications for personalized medicine. The findings underscore the versatility of intelligent systems in addressing health challenges, emphasizing the broader applications of ML and DL in disease identification beyond cardiovascular health. 展开更多
关键词 Cardiovascular Disease Machine Learning Deep Learning Predictive Modeling Risk Assessment Comparative Analysis Gradient Boosting LSTM
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Stable lithium metal anode enabled by a robust artificial fluorinated hybrid interphase
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作者 Qiwen Ran Hongyuan Zhao +5 位作者 Jintao Liu Lei Li Qiang Hu Jiangxuan Song Xingquan Liu Sridhar Kormarneni 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第8期612-621,I0014,共11页
One of the key challenges for achieving stable lithium(Li) metal anode is the construction of the rational solid electrolyte interphase(SEI),but its realization still faces enormous challenges.In this work,a robust ar... One of the key challenges for achieving stable lithium(Li) metal anode is the construction of the rational solid electrolyte interphase(SEI),but its realization still faces enormous challenges.In this work,a robust artificial fluorinated hybrid interphase consisting of lithium-bismuth(Li3Bi) alloy and lithium-fluoride(LiF) was designed to regulate Li deposition without Li dendrite growth.The obtained hybrid interphase showed the high Li+diffusion rate(3.5 × 10^(-4)S cm^(-1)),high electron resistivity(9.04 × 10^(4)Ω cm),and high mechanical strength(1348 MPa),thus enabling the uniform Li deposition at the Li/SEI interface.Specifically,Li3Bi alloy,as a superionic conductor,accelerated the Li+transport and stabilized the hybrid interphase.Meanwhile,LiF was identified as a superior electron-blocker to inhibit the electron tunneling from the Li anode into the SEI.As a result,the modified Li anode showed the stable Li plating/stripping behaviors over 1000 cycles even at 20 mA cm^(-2).Moreover,it also enabled the Li(50 μm)‖LiNi_(0.8)Co_(0.1)Mn_(0.1)O_(2)(4.4 mA h cm^(-2)) full cell to achieve an average Coulombic efficiency(CE) of 99.6%and a high-capacity retention of 79.2% after 100 cycles,whereas the bare Li anode only exhibited a low-capacity retention of 8.0%.This work sheds light on the internal mechanism of Li+transport within the hybrid interface and provides an effective approach to stabilize the interface of Li metal anode. 展开更多
关键词 Li metal anode Artificial interphase Li Bi alloy LIF Uniform Li deposition
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How a Cancer Registry Was Set Up in Senegal: An Example to Follow for a Developing Country
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作者 Salif Baldé Sokhna Diop Niang +1 位作者 Oumar Ba Mamadou Diop 《Journal of Cancer Therapy》 2023年第9期382-389,共8页
Objectives: Senegal, with the support of WHO, had begun the establishment of a National Cancer Registry in 2009, although it had been at a standstill since 1969;the objective of this work was to test the reliability o... Objectives: Senegal, with the support of WHO, had begun the establishment of a National Cancer Registry in 2009, although it had been at a standstill since 1969;the objective of this work was to test the reliability of data collection tools and feasibility stages necessary for the validation of media before the establishment of a national cancer registry. Methodology: We conducted a non-exhaustive preliminary study over a period of three months from the first of January to 31 March 2010 at four major hospitals in Dakar at the time. Results: Two hundred and eighty-nine cases had been identified: 44% of men (n = 127) and 56% of women (n = 162) with a sex ratio of 0.8. The ages ranged from 20 to 90 years with an average of 50 years. The main diagnostic mode was essentially histological, with 76% of cases (n = 219). The most frequent locations were: ORL (ENT meaning Ear, Nose and Throat) with 25% of cases, liver 7% and bronchopulmonary 4.5% of cases. In men, liver cancer was the most common location and women for cervical cancer with 16%. Squamous cell carcinoma was the most common histological type with 68% of cases followed by adenocarcinoma with 22% of cases. Thirty-eight percent of patients were classified as stage III and IV. A quarter of our patients had received palliative treatment. In contrast, 15 (15%) had received chemotherapy and 4% had received radiotherapy. Data collection was satisfactory. Conclusion: Cancer is a reality in Senegal but it remains underdiagnosed. The materials made it possible to make the cancer registry effective throughout the country. 展开更多
关键词 REGISTRY CANCER Senegal
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Human Kallikrein-2 and Free Prostate Specific Antigen as Biomarkers for Early Detection of Prostate Cancer, Sudan: A Case-Control Study
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作者 Osman Khalid Yousif Badreldin Elsonni Abdalla +4 位作者 Mohammed Alimam M. Ahmed Sami Mahjoub Taha Ahmed Al Siddiq Ebraheem Muawia Mohamed Ahmed Elhadi Abdalla Ahmed 《Open Journal of Clinical Diagnostics》 2023年第1期9-21,共13页
Background: Prostate cancer (PCa) is considered one of the major health threats facing males in Sudan. Prostate-specific antigen (PSA) test is the most important laboratory test used in the diagnosis of prostate cance... Background: Prostate cancer (PCa) is considered one of the major health threats facing males in Sudan. Prostate-specific antigen (PSA) test is the most important laboratory test used in the diagnosis of prostate cancer, the main disadvantage of PSA is its limited specificity, which triggered a lot of interest in development, more research on other markers such as serum human kallikrein-2 (KLK-2) and free prostate specific antigen (fPSA). Objectives: To evaluate the validity of serum kallikrein-2 (KLK-2) and free prostate specific antigen (fPSA) in the early detection of prostate cancer among Sudanese patients. Method: In this study seventy men were considered as a case subject, who were diagnosed as cancer prostate at Gezira Hospital for Renal Disease and Surgery (GHRDS), Sudan during the period February 2018 to July 2019. Randomly selected sixty patients of BPH patients and forty-five apparently healthy men as control subject. KLK-2, fPSA and PSA estimations were performed from serum samples using the principle of Enzyme Linked Immunosorbent Assay (ELISA). Results: The results revealed a highly significant difference between the serum levels individual biomarkers (KLK-2, fPSA, PSA) and multiple biomarkers (fPSA/PSA, KLK-2/fPSA, KLK-2/PSA) for patients with prostate cancer when compared with the control groups. Furthermore, the fPSA/PSA ratio was lower in the patients with prostate cancer (P value = 0.00) than in the control group, the fPSA/PSA ratio showed that best accuracy to differentiate prostate cancer from control group, fPSA cut-off value was found to be more than (18 ng/ml), with sensitivity (93%), specificity (80%), and odds ratio (55). Conclusions: The use of multiple biomarkers rather than individual biomarkers especially fPSA/PSA ratio improves the specificity as well as maintenance of higher sensitivity for early diagnosis of the prostate cancer. 展开更多
关键词 Kallikrein-2 PSA FPSA Prostate Cancer SUDAN
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Nutritional therapy for gastroparesis
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作者 Zhen Wang Qin-Zhou Song +2 位作者 Jin-Xun Jiang Xiang-Hua Wu Jun-Qiang Chen 《Journal of Nutritional Oncology》 2023年第1期25-30,共6页
Gastroparesis is a common postoperative complication of abdominal surgery,mainly manifested by postprandial fullness,early satiety,nausea,vomiting,and bloating.Gastroparesis should be addressed with a comprehensive tr... Gastroparesis is a common postoperative complication of abdominal surgery,mainly manifested by postprandial fullness,early satiety,nausea,vomiting,and bloating.Gastroparesis should be addressed with a comprehensive treatment plan that includes nutritional therapy and medications such as metoclopramide,domperidone,cisapride,and antiemetic drugs.Surgical treatment,such as pyloroplasty or partial gastrectomy,should be considered if the conservative therapy is ineffective.Enteral and parenteral nutrition therapy can promote the recovery of gastrointestinal function,maintain the mucosal integrity and immunity,and reduce complications.Thus,nutrition can play an important role in the treatment of gastroparesis. 展开更多
关键词 GASTROPARESIS Nutritional therapy SURGERY
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A Prospective, Multicentric, Post Marketing Surveillance to Evaluate Efficacy & Safety of Ranitidine HCl (150 & 300 mg IR/CR) in Indian Patients with Gastroesophageal Reflux Disease (PROGRADE)
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作者 Akash Shukla Anil Kumar Awasthi +10 位作者 Ramesh Rao Dawesh Prakash Yadav Nilesh Nolkha Rajesh Pendlimari Sanjiv Dua Shrish Bhatnagar Ravindra Mote Ashish Birla Jay Savai Kapil Mehta Shashank Salunke 《Open Journal of Gastroenterology》 2023年第7期237-249,共13页
Purpose: Ranitidine hydrochloride (HCl) remains an important medication for treating acid-peptic ailments such as Gastroesophageal reflux disease (GERD). The main objective of this Post Marketing Surveillance (PMS) cl... Purpose: Ranitidine hydrochloride (HCl) remains an important medication for treating acid-peptic ailments such as Gastroesophageal reflux disease (GERD). The main objective of this Post Marketing Surveillance (PMS) clinical study was to test the efficacy and safety of Ranitidine HCl in Indian patients suffering from GERD. Patients and Methods: Data of 2446 patients (1307 males;1121 females) from 21 centers across India were analyzed. Patients received either of the three treatments: Ranitidine HCl 150 mg twice a day (BID) (ARM-A), Ranitidine HCl 300 mg once daily (OD) or BID (ARM-B), and Ranitidine HCl 300 mg OD (ARM-C). Gastroesophageal Reflux Disease Symptom Assessment Scale (GSAS) score and Heartburn Severity score were used to assess the drug’s efficacy. The adverse events reported by patients or investigators were analyzed to assess the safety profile of Ranitidine. Results: Of the 2446 subjects screened, 2428 were enrolled. There was a significant reduction in GSAS scores from baseline to the end of the study visit in all three ARMs. The GSAS scores reduced from 2.02 to 0.23 in ARM-A, 2.01 to 0.24 in ARM-B, and 2.07 to 0.26 in ARM-C patients. In ARM A, 72.82% had 24 hours heartburn-free days, and 66.89% had 7 consecutive heartburn-free days, which was more significant than the other two ARMs. 128 (5.27%) patients reported ADRs due to Ranitidine HCl at different doses. The most frequently reported ADR was constipation (17.18%), followed by oliguria (14.06%), cold (13.28%), and dysuria (12.5%). Of 128 ADRs, 113 (88.28%) were mild, and only 11 (8.59%) ADRs were related to the study drug. No severe ADRs were reported during the study. Conclusion: Ranitidine HCl 150/300 mg tablet was found to be an effective and safe H2-receptor antagonist for treating GERD in Indian Patients. 展开更多
关键词 Ranitidine Hydrochloride GERD HEARTBURN H2-Receptor Antagonists
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行为安全“2-4”模型及其在煤矿安全管理中的应用 被引量:283
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作者 傅贵 殷文韬 +2 位作者 董继业 Di FAN Cherrie Jiuhua ZHU 《煤炭学报》 EI CAS CSCD 北大核心 2013年第7期1123-1129,共7页
通过观察事故统计得知,几乎100%的生产安全事故是责任事故,且是由于事故单位的"管理漏洞"所引起。理论分析得知,应用古典、近代及已有的现代事故致因链不能够精确定位"管理漏洞"的具体位置和内容,事故预防困难。根... 通过观察事故统计得知,几乎100%的生产安全事故是责任事故,且是由于事故单位的"管理漏洞"所引起。理论分析得知,应用古典、近代及已有的现代事故致因链不能够精确定位"管理漏洞"的具体位置和内容,事故预防困难。根据组织行为学原理,并研究国内外已有事故致因链发现并提出了行为安全"2-4"模型这个新型现代事故致因链。在该模型中,将事故的原因首先分解为组织行为、组织成员个人行为两个层面,然后再将组织行为继续细化分解为指导行为、运行行为,将个人行为细化分解为习惯性行为、一次性行为4个行为阶段,分别对应事故的根源、根本、间接、直接原因,具体内容分别是安全文化,安全管理体系,安全知识、意识和习惯,不安全动作和不安全状态。煤矿事故案例分析证实,应用该模型,且把"安全管理"表达为"行为控制"之后,可以将导致事故发生的关键原因"管理漏洞"、"管理缺欠"理解为"行为控制缺欠",并可将其精确定位在"2"个层面、"4"个行为阶段的其中一个或几个上面,据此即可制定有效、明确的事故预防措施。 展开更多
关键词 行为安全模型 事故原因 管理漏洞 准确定位 煤矿事故
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AZ91 Mg-Al合金中β-(Mg_(17)Al_(12))析出相的形态及其晶体学特征 被引量:60
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作者 肖晓玲 罗承萍 +1 位作者 聂建峰 B.C.Muddle 《金属学报》 SCIE EI CAS CSCD 北大核心 2001年第1期1-7,共7页
应用透射电镜研究了时效AZ91 Mg-Al合金连续析出相的显微组织形态及晶体学特征。发现四种不同形态和晶体学特征的β-(Mg17Al12)析出相,其中占绝大多数的是板条状析出相沿基面(0001)α析出的板条析出相与基... 应用透射电镜研究了时效AZ91 Mg-Al合金连续析出相的显微组织形态及晶体学特征。发现四种不同形态和晶体学特征的β-(Mg17Al12)析出相,其中占绝大多数的是板条状析出相沿基面(0001)α析出的板条析出相与基体保持Burgers位向关系,生长方向为[7, 2,9,0];其晶体学特征与由不变线应变原理预测的完全一致。第二类析出相是以其轴线与基面垂直的六棱柱体,六个棱柱面都是{1100}α//{110}β,与基体保持对称性好的Crawley位向关系。另有少量短棒状析出相与基体保持Porter位向关系。实验中还观察到一种未见报道过的位向关系。讨论了形成不同形态和晶体学特征的机制。 展开更多
关键词 AZ91MG-AL合金 β-(MG17AL12)析出相 透射电镜分析 晶体学特征 镁合金
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血管内皮生长因子和表皮生长因子信号通路的联合抑制在非小细胞肺癌治疗中的应用 被引量:27
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作者 南娟 刘谦 +3 位作者 丁燕 张占雀 Allen C.Gao 周清华 《中国肺癌杂志》 CAS 2009年第12期1316-1324,共9页
肺癌是全球癌症相关死亡的首位原因,已成为人类面临的日益严重的公共卫生问题,各国政府均投入了大量的人力物力,以期在肺癌研究领域有所突破。大约50%新诊断的肺癌已属晚期,对于这些患者可采用姑息性系统治疗法。系统化疗是目前治疗非... 肺癌是全球癌症相关死亡的首位原因,已成为人类面临的日益严重的公共卫生问题,各国政府均投入了大量的人力物力,以期在肺癌研究领域有所突破。大约50%新诊断的肺癌已属晚期,对于这些患者可采用姑息性系统治疗法。系统化疗是目前治疗非小细胞肺癌(non—small cell lung cancer,NSCLC)的主要措施。许多基于顺铂的联合方案和单药疗法常用于晚期NSCLC患者不同阶段的治疗。 展开更多
关键词 非小细胞肺癌 血管内皮生长因子 表皮生长因子 治疗法 联合抑制 信号通路 公共卫生问题 cell
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基于NDVI数据的黄河流域地表植被覆盖综合分类研究 被引量:17
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作者 李道峰 田英 郝芳华 《水土保持研究》 CSCD 2003年第4期88-91,共4页
在地理信息系统支持下,文章以时间分辨率为植物一个完整生长周期、空间分辨率1km×1km的NOAA/AVHRR遥感影像的NDVI指标为数据源,采用目前较为流行的主成分变换法,结合气象资料和数字高程模型(DEM),参考相关的地理基础图件,对黄河流... 在地理信息系统支持下,文章以时间分辨率为植物一个完整生长周期、空间分辨率1km×1km的NOAA/AVHRR遥感影像的NDVI指标为数据源,采用目前较为流行的主成分变换法,结合气象资料和数字高程模型(DEM),参考相关的地理基础图件,对黄河流域地表植被覆盖的进行综合分类。与传统对单一NOAA/AVHRR图像NDVI数据进行分类的方法相比,综合分类方法获得了较高的分类精度,取得了较好的效果。 展开更多
关键词 黄河流域 地表植被覆盖 NDVI 主成分变换
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迭代法ECT对循环流化床底部固体浓度的测量 被引量:2
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作者 刘石 许华 +2 位作者 王海刚 姜凡 杨五强 《工程热物理学报》 EI CAS CSCD 北大核心 2002年第6期757-760,共4页
在矩形循环流化床底部固体浓度的测量中首次采用了迭代电容层析成象方法,比通用的线性逆映射方法明显提高了成象质量。通过层析成象分析得到了床层中固体浓度分布、平均固体浓度随时间的变化和频谱特性。
关键词 ECT 循环流化床 底部固体浓度 测量 电容层析成像 迭代成象法
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青少年及儿童近视进展及其危险因素 被引量:12
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作者 林仲 梁远波 +2 位作者 李晓霞 Balamurali Vasudevan Kenneth J Ciuffreda 《中华实验眼科杂志》 CAS CSCD 北大核心 2015年第12期1148-1152,共5页
近视是全球重要的公共卫生问题。青少年及儿童近视患病率因在全球范围,尤其在亚洲地区,快速增长且影响因素复杂多样而受到广泛关注。尽管目前已有大量关于青少年及儿童近视进展及其危险因素的报道,然而由于人群、近视定义、睫状肌麻... 近视是全球重要的公共卫生问题。青少年及儿童近视患病率因在全球范围,尤其在亚洲地区,快速增长且影响因素复杂多样而受到广泛关注。尽管目前已有大量关于青少年及儿童近视进展及其危险因素的报道,然而由于人群、近视定义、睫状肌麻痹剂、验光方法等不同导致彼此间难以比较。本文就1990年至今关于青少年(〈18岁)和儿童近视进展及其与年龄、性别、屈光状态、近距工作、户外活动、父母近视或父母生育年龄等危险因素关系的报道进行总结。 展开更多
关键词 近视 进展 危险因素
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我国能源供给与消费优化精准配置探讨——以浅层地热能与建筑物供暖制冷配置为例 被引量:8
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作者 武强 涂坤 +3 位作者 徐生恒 曾一凡 刘守强 朱柯 《中国能源》 2020年第5期4-7,19,共5页
当前我国面临着资源约束矛盾突出、能源利用效率低和应对气候变化等问题。要圆满解决这些矛盾和问题,不仅需要能源消费侧和供给侧的革命,而且消费侧与供给侧之间能源如何优化精准配置也同样十分重要。本文系统地阐述了能源供给与消费优... 当前我国面临着资源约束矛盾突出、能源利用效率低和应对气候变化等问题。要圆满解决这些矛盾和问题,不仅需要能源消费侧和供给侧的革命,而且消费侧与供给侧之间能源如何优化精准配置也同样十分重要。本文系统地阐述了能源供给与消费优化精准配置的原理和内涵;以建筑物供暖与制冷能源需求为例,科学地分析了浅层地热能为建筑物供暖制冷在品位上、空间上和时间上配置的合理性。在新时代推进能源生产和消费革命的背景下,开展我国能源供给与消费优化精准配置研究,对更好地积极应对能源、环境与经济带来的挑战具有战略性意义,对提高我国能源利用效率有重要现实意义。 展开更多
关键词 能源供给 消费优化 精准配置 浅层地热能
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素食人群尿液^1H NMR代谢轮廓的多因素方差分析 被引量:4
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作者 董继扬 邓伶莉 +2 位作者 CHENG Kian-Kai GRIFFI NJulian L. 陈忠 《高等学校化学学报》 SCIE EI CAS CSCD 北大核心 2011年第12期2769-2776,共8页
结合方差分析(ANOVA)和偏最小二乘法判别分析(PLS-DA)两种分析技术,对素食和普食人群的尿液1H NMR谱进行分析.利用ANOVA方法将数据矩阵分解为几个独立因素矩阵,滤除干扰因素后,再利用PLS-DA对单因素数据进行建模分析.实验结果表明,ANOVA... 结合方差分析(ANOVA)和偏最小二乘法判别分析(PLS-DA)两种分析技术,对素食和普食人群的尿液1H NMR谱进行分析.利用ANOVA方法将数据矩阵分解为几个独立因素矩阵,滤除干扰因素后,再利用PLS-DA对单因素数据进行建模分析.实验结果表明,ANOVA/PLS-DA方法可以有效地减少饮食因素和性别因素之间的相互影响,使分析结果更具有生物学意义. 展开更多
关键词 多因素分析 方差分析 偏最小二乘法判别分析 核磁共振代谢组学
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空间发展湍流气粒两相平面混合层的大涡模拟与统计 被引量:2
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作者 柳朝晖 李勇 +1 位作者 郑楚光 周向阳 《工程热物理学报》 EI CAS CSCD 北大核心 2002年第4期495-498,共4页
本文对空间发展的湍流气固两相平面混合层流动进行了大涡模拟研究,其中气相亚网格尺度(SGS)使用结构函数模型,气相控制方程组采用SIMPLE方法求解,固体颗粒运动用拉格朗日方法计算。计算结果正确重现了流体涡结构的卷起、合并和破碎过... 本文对空间发展的湍流气固两相平面混合层流动进行了大涡模拟研究,其中气相亚网格尺度(SGS)使用结构函数模型,气相控制方程组采用SIMPLE方法求解,固体颗粒运动用拉格朗日方法计算。计算结果正确重现了流体涡结构的卷起、合并和破碎过程,以及小尺寸颗粒在涡边缘(低涡度区)的局部富集现象。对直径分别为42μm、72μm和135μm分别进行了模拟,并将统计结果和实验测量结果(Hishida et al[1])比较,表明两者的平均速度吻合很好,但颗粒数密度和脉动速度存在较明显的差异,因此有必要对亚网格应力和颗粒之间的耦合作用以及拟序结构的三维性对颗粒运动的影响开展深入研究。 展开更多
关键词 大涡模拟 气粒两相流 平面混合层
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硝酸甘油介入^(99)Tc^m-tetrofosminSPECT与^(18)F-FDG PET显像评估心肌活力比较 被引量:6
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作者 何薇 Alberto Cuocolo 《中华核医学杂志》 CAS CSCD 北大核心 2007年第5期278-281,共4页
目的比较硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT 心肌血流灌注显像与^(18)F-FDG PET 心肌代谢显像评估心肌活力的价值。方法既往有心肌梗死史伴左心功能不全经冠状动脉造影确诊为冠心病的患者36例,行二日法静息和硝酸甘油介入^(99)Tc... 目的比较硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT 心肌血流灌注显像与^(18)F-FDG PET 心肌代谢显像评估心肌活力的价值。方法既往有心肌梗死史伴左心功能不全经冠状动脉造影确诊为冠心病的患者36例,行二日法静息和硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT 显像,并在1周内再行^(18)F-FDG PET 心肌代谢显像及静息超声心动图检查。将左心室分成13个节段,分析超声心动图室壁运动,并分析相同节段^(99)Tc^m-tetrofosmin 与^(18)F-FDG 的相对摄取比值,以^(99)Tc^m-tetrofosmin 摄取比值55%,^(18)F-FDG 摄取比值50%为判断心肌活力有无的阈值。以 k 统计比较3种方法的一致性。结果超声心动图示131个节段呈无运动或反向运动。^(99)Tc^m-tetrofosmin 静息显像示其中78个节段(60%)心肌有活力,53个节段(40%)无活力。该53个节段中14个(26%)在硝酸甘油介入后可见再填充,余39个节段无改变。在^(18)F-FDG PET 显像中,硝酸甘油介入显像再填充节段的心肌放射性摄取明显增高。再填充节段与无填充节段比较,心肌 FDG 摄取分别为(76±15)%和(58±17)%,差异有统计学意义(P<0.01)。硝酸甘油介入显像中,92个心肌节段(70%)有活力,39个无活力。tetrofosmin静息显像评估心肌活力与 FDG PET 显像比较,k 值为0.35,而硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT与^(18)F-FDG PET 显像结果比较,k 值为0.53。结论硝酸甘油介入^(99)Tc^m-tetrofosmin SPECT 显像可提高对心肌活力的检测能力,与^(18)F-FDG PET 心肌代谢显像有很好的一致性。 展开更多
关键词 心肌梗塞 硝酸甘油 TETROFOSMIN 体层摄影术 发射型计算机 单光子 脱氧葡萄糖 体层摄影术 发射型计算机
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中国六省儿童HIV感染者的流行病学调查 被引量:17
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作者 赵燕 郭万申 +8 位作者 贾曼红 乔晓春 刘伟 姚旋 李传涛 豆智慧 李在村 汪宁 张福杰 《中国医学科学院学报》 CAS CSCD 北大核心 2006年第5期655-657,共3页
目的了解中国六省儿童HIV感染者的流行病学状况。方法对6个艾滋病高发省份的儿童感染者进行横断面调查,采集患者人口学、感染途径、诊断时间、临床分期、实验室检测等数据。结果共650例患儿入选,男405例,女245例,平均年龄(7.9±3.2)... 目的了解中国六省儿童HIV感染者的流行病学状况。方法对6个艾滋病高发省份的儿童感染者进行横断面调查,采集患者人口学、感染途径、诊断时间、临床分期、实验室检测等数据。结果共650例患儿入选,男405例,女245例,平均年龄(7.9±3.2)岁,可能感染到确诊的平均时间间隔为(7.1±3.2)年。依次分布于河南570例(87.7%),广西23例(3.5%),云南21例(3.2%),湖北19例(2.9%),安徽10例(1.5%),山西7例(1.1%)。其中母婴传播488例(75.1%),输血及血制品传播102例(15.7%),静脉吸毒传播3例(0.5%)。以采供血为主要传播途径的省份(包括河南、山西、湖北、安徽)和以静脉吸毒为主要传播途径的省份(包括广西、云南)感染者的平均年龄分别为(8.1±3.2)和(5.4±2.2)岁,两组相比差异有显著性(P<0.001)。178例(39.3%,178/453)符合接受抗病毒治疗标准,其中133例(74.7%,133/178)未接受治疗,45例(25.3%,45/178)采用成人药物治疗。结论母婴传播是儿童感染HIV的主要途径,应当加强我国儿童HIV感染者的诊断和治疗工作。 展开更多
关键词 儿童 人类免疫缺陷病毒 感染 流行病学
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小鼠3种α1,2岩藻糖转移酶的底物特异性 被引量:1
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作者 林蓓 齐藤真木子 岩森正男 《中国医学科学院学报》 CAS CSCD 北大核心 2005年第6期761-766,共6页
目的对比小鼠3种GDP岩藻糖O!半乳糖苷"112-岩藻糖转移酶("112-FT)的底物特异性。方法利用RT-PCR方法克隆小鼠3种"112-FT基因编码区MFUT-Ⅰ、MFUT-Ⅱ、MFUT-Ⅲ,测序后分别将其插入表达载体pcDNA3.1的多克隆位点,构建表达... 目的对比小鼠3种GDP岩藻糖O!半乳糖苷"112-岩藻糖转移酶("112-FT)的底物特异性。方法利用RT-PCR方法克隆小鼠3种"112-FT基因编码区MFUT-Ⅰ、MFUT-Ⅱ、MFUT-Ⅲ,测序后分别将其插入表达载体pcDNA3.1的多克隆位点,构建表达载体pcDNA3.1-MFUT-Ⅰ、pcDNA3.1-MFUT-Ⅱ及pcDNA3.1-MFUT-Ⅲ;采用磷酸钙法将其转染于COS-7细胞进行表达,通过检测3种酶对不同种底物特性比较酶的特异性。结果小鼠基因MFUT-Ⅰ、MFUT-Ⅱ、MFUT-Ⅲ分别与人类H基因(77%)、Se基因(79%)和Sec1基因(75%)具有序列同源性。MFUT-Ⅰ和MFUT-Ⅱ基因转染后的COS-7细胞均具有"112-FT活性1而MFUT-Ⅲ基因转染的COS-7细胞无此活性。MFUT-Ⅱ同时对底物缺乏唾液酸的神经节苷脂(GA1)及单唾液酸四己糖神经节苷脂(GM1)存在活性1分别生成产物岩藻糖基化GA1(FGA1)及岩藻糖基化神经节苷脂GM1(FGM1)<而MFUT-Ⅰ仅对底物GA1存在活性。MFUT-Ⅱ对GA1的比活性约为MFUT-Ⅰ的80~90倍。MFUT-Ⅱ对GA1的比活性为GM1的10 ̄20倍。MFUT-Ⅱ不仅具有合成Ⅳ型H抗原FGA1及FGM1活性,同时具有对乳丁糖神经酰胺(Lc4Cer)及异乳丁糖神经酰胺(nLc4Cer)的活性,可合成Ⅰ型及Ⅱ型H抗原。结论MFUT-Ⅱ是小鼠的主要"112-FT,具有合成Ⅳ型H抗原FGA1及FGM1的功能;MFUT-I仅有合成Ⅳ型H抗原FGA1的功能;MFUT-Ⅲ无"112-FT活性。 展开更多
关键词 小鼠 α1 2-岩藻糖转移酶 基因 糖脂 底物特异性
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去B环喜树碱的合成
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作者 刘建利 R.T.Brown 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 1999年第S1期98-98,共1页
关键词 喜树碱 B环 药物化学 衍生物 生物合成 抗癌作用 抗癌药 原料合成 合成路线 有机化
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