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新修定的化学防护服国家标准解析

纺织学报 2024年第3期45卷 163-168页

作者：杨光杨小兵栗丽姚之凤周川张明明国民核生化灾害防护国家重点实验室北京100191 雾霾健康效应与防护北京市重点实验室北京100191 中国安全生产科学研究院北京100012

为厘清化学防护服国家标准修订后的情况,通过分析我国化学防护服国家标准发展历史,研究国外化学防护服标准,重点针对修订后的GB 24539—2021《防护服装化学防护服》的变化,从化学防护服的分类、性能要求、试验方法等方面对该标准加以解... 详细信息

为厘清化学防护服国家标准修订后的情况,通过分析我国化学防护服国家标准发展历史,研究国外化学防护服标准,重点针对修订后的GB 24539—2021《防护服装化学防护服》的变化,从化学防护服的分类、性能要求、试验方法等方面对该标准加以解读。分析发现:GB 24539—2021将相关标准进行整合,对化学防护服的分类进行了较大的调整和更新,删除了非气密型化学防护服-ET,增加了气密型化学防护服、有限泼溅化学防护服和织物酸碱类化学防护服;相应地,性能要求也产生了较大变化,主要包括服装整体防护性能、服装面料防护性能及服装面料理化性能;GB 24539—2021中的大部分试验方法沿用了之前相关标准中的试验方法,但也进行了相应的改进和完善,主要包括试样预处理条件和试验环境条件、化学防护服向内泄漏率测试方法、化学防护服液密性能测试方法、化学防护服面料耐磨损性能测试方法和耐屈挠破坏性能测试方法。

关键词：国家标准防护服装化学防护服防护性能耐磨损性能

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水中旋转圆盘振动阻尼测量与模拟

北京理工大学学报 2024年第4期44卷 377-385页

作者：姚志峰刘宝熙曾永顺白绵绵王福军中国农业大学水利与土木工程学院北京100083 清华大学能源与动力工程系北京100084 陕西省水利电力勘测设计研究院陕西西安710001 北京市供水管网系统安全与节能工程技术研究中心北京100083

为了研究模态做功法在计算旋转式机械水力阻尼时的适用性和准确性,利用旋转圆盘阻尼测量系统的实验数据对该方法做了评估.研究表明,圆盘的水力阻尼值随转速的增加呈现下降的趋势;利用模态做功法计算水力阻尼值时必须考虑旋转效应带来的... 详细信息

为了研究模态做功法在计算旋转式机械水力阻尼时的适用性和准确性,利用旋转圆盘阻尼测量系统的实验数据对该方法做了评估.研究表明,圆盘的水力阻尼值随转速的增加呈现下降的趋势;利用模态做功法计算水力阻尼值时必须考虑旋转效应带来的影响,如果直接使用静止条件下的模态结果,水力阻尼随转速的变化规律将完全和实验结果相反;在考虑旋转的条件下,计算精度有所提高,但整体呈现过预测的问题,该方法对旋转结构阻尼特性的预测精度还有待提高.

关键词：圆盘旋转振动模态做功水力阻尼

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Dosimetry of chimeric TNT in lung tumor patients

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Nuclear Science and Techniques 2007年第4期18卷 227-231页

作者： CHEN Yangchun CHEN Shaoliang JU Dianwen SHI Hongcheng yao zhifeng Nuclear Medicine Department Zhongshan Hospital Fudan University Shanghai200032 China PET/CT Center of the First Affiliated Hospital of Guangzhou Medical College Guangzhou 510230 China Shanghai MediPharm Biotech Co Ltd Shanghai 201203 China

The purpose of this study was to assess the absorbed dose of tumor and main critical organs in 131I labeled chimeric tumor necrotic treatment (chTNT). In 9 patients, a single intravenous dose of (29.6±3.7) MBq/kg was administered. Blood samples were drawn at different time intervals, and urine was collected for up to one week. Tissue distribution of 131I-chTNT was followed for up to one week by gamma camera imaging. Absorbed doses to the whole body and to normal organs were computed according to the MIRD scheme using Mirdose-3 software. S-factors for lung tumors were estimated by comparison with lungs of similar mass and position in the body. It was found that mean serum disappearance half time values for 131I-chTNT were (4.93±9.36) h and (61.7±21.2) h for α, β respectively, while that for whole body was(99±10) h. Mean urine biological clearance half time value was (90±10) h. The absorbed dose to tumor was (8.28±2.65) Gy, and the tumor-to-nontumor dose ratio was 3.95±1.55. And the mean effective dose to patients was (1.02±0.29) mSv/MBq.

关键词：肺癌放射疗法放射量碘放射性同位素

A general alternate loading technique and its applications in the inverse designs of centrifugal and mixed-flow pump impellers

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Science China(Technological Sciences) 2021年第4期64卷 898-918页

作者： WANG ChaoYue WANG FuJun AN DongSen yao zhifeng XIAO RuoFu LU Li HE ChengLian ZOU ZhiChao College of Water Resources and Civil Engineering China Agricultural UniversityBeijing 100083China Beijing Engineering Research Center of Safety and Energy Saving Technology for Water Supply Network System Beijing 100083China China Institute of Water Resources and Hydropower Research Beijing 100038China China Water Resources Beifang Investigation Design and Research Co.Ltd.Tianjin 300222China

For the inverse designs of centrifugal and mixed-flow pump impellers,clarifying the generation process of secondary flows and putting forward corresponding suppression measures is an important approach to improve the impeller *** this paper,to provide a better qualitative insight into the generation mechanism of secondary flows in the impeller,a simple kinematic equation is derived based on the ideal assumptions,which indicates that the potential rothalpy gradient(PRG)is the most important dynamic source that actively induces secondary vortical *** by the natural adverse PRG on the S1 and S2 stream surfaces,two typical secondary flows,H-S and P-S secondary flows,are clearly *** specially suppress these typical secondary flows,a general alternate loading technique(GALT)is proposed,aiming to adjust the real blade loadingδp to control the PRG *** the blade fore part,theδp on the hub streamline should be slowly increased to avoid breakneck growth of the potential rothalpy to reduce adverse streamwise PRG on the S2 *** the blade middle part,theδp should be moderately decreased to reduce adverse streamwise PRG on the S1 *** the blade aft part,the difference in theδp between the shroud and hub streamlines should be decreased faster to control the exit *** applying the GALT to the impeller designs of three typical pump types in hydraulic engineering,the organizational effect of the PRG on fundamental flow structures is *** GALT can effectively control the PRG distributions and suppress the secondary flows,thereby widening the pump’s high-efficiency zone,improving flow uniformity and suppressing pressure *** with the current Z-G method and the ALT,the GALT can meet the requirements of"de-experience"better,thereby enabling the designers to obtain good products explicitly and quickly.

关键词： alternate loading technique inverse design centrifugal pump mixed-flow pump impeller potential rothalpy gradient

无创左室压力应变曲线在冠心病心肌缺血诊断中的价值

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中国临床医学 2024年第3期31卷 411-419页

作者：赵盈洁何芙蓉何玮过伟锋赵士海葛振一姚志锋陈海燕潘翠珍舒先红上海市影像医学研究所上海200032 复旦大学附属中山医院心脏超声诊断科上海200032 复旦大学附属中山医院心内科上海200032 复旦大学基础医学院上海200032 复旦大学附属中山医院血管外科上海200032 复旦大学附属中山医院放射科上海200032

目的以冠状动脉血流储备分数(fraction flow reservation,FFR)为金标准,采用无创左室压力应变环(pressure strain loop,PSL)评价心肌做功相关参数对冠状动脉粥样硬化性心脏病(coronary artery disease,CAD)心肌缺血的诊断价值。方法前... 详细信息

目的以冠状动脉血流储备分数(fraction flow reservation,FFR)为金标准,采用无创左室压力应变环(pressure strain loop,PSL)评价心肌做功相关参数对冠状动脉粥样硬化性心脏病(coronary artery disease,CAD)心肌缺血的诊断价值。方法前瞻性纳入2020年12月至2021年12月在复旦大学附属中山医院就诊的53例临床疑似CAD患者,均进行超声心动图检查、有创冠状动脉造影和FFR测量。根据冠脉造影结果将患者分为心肌缺血组(FFR≤0.8,24例)和非心肌缺血组(FFR>0.8,29例)。采用PSL进行脱机分析,获得左室整体做功指数(global work index,GWI)、整体有效功(global constructive work,GCW)、整体无效功(global wasted work,GWW)、整体做功效率(global work efficiency,GWE)、整体正向功(global positive work,GPW)及整体收缩期有效功(global systolic constructive work,GSCW)等心肌做功参数值,进行两组间比较。采用ROC曲线分析心肌做功参数对心肌缺血的诊断效能。结果在18、16和12节段水平,与非心肌缺血组相比,心肌缺血组GWI、GCW、GPW、GSCW均降低(P<0.001)。ROC曲线显示,GWI、GCW、GPW、GSCW在18节段水平AUC分别为0.803(95%CI 0.679~0.927)、0.807(95%CI 0.687~0.928)、0.822(95%CI 0.708~0.936)、0.819(95%CI 0.703~0.935)。其中,GWI最佳截断值为1676.3 mmHg%,预测心肌缺血的灵敏度、特异度和准确度分别为70.8%、86.2%和79.2%;GCW最佳截断值为1999.4mmHg%,预测心肌缺血的灵敏度、特异度和准确度分别为75.0%、82.8%和79.2%。结论采用PSL分析心肌做功对CAD心肌缺血人群有较好的筛查作用。

关键词：超声心动图压力应变环血流储备分数冠心病心肌缺血

Comparative Analysis between Clinicopathologic Characteristics and Prognosis in Patients with Local and Infiltrative Gastric Cancer

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Clinical oncology and cancer resexreh 2009年第6期6卷 430-435页

作者： zhifeng Miao yao Lin Xiaoying Li Huimian Xu Department of Gastrointestinal Surgical Oncology The First Affiliated Hospital of China Medical University Shenyang 110001 Liaoning Province China

OBJECTIVE To investigate the differences between theclinicopathologic characteristics and prognostic factors in patientswith localized and infiltrative gastric cancer (GC).METHODS Patients with advanced GC, who were admittedto the Department of Surgical Oncology of the First AffiliatedHospital of China Medical University, Shenyang, during a periodof January 1980-January 2000, were divided into the localizedand infiltrative GC groups. A comparative analysis of theclinicopathologic data and prognosis in the patients enrolled in thestudy was carried out based on the different macroscopic *** There were significant differences in the sex ratio,tumor location, histologic type, depth of invasion, lymph nodemetastasis, lymphovascular cancer embolus (LVCE), growthpattern, and degree of radical surgery between the 2 ***, there were no significant differences in age, tumorsize, and intravenous cancer embolus between the 2 *** prognosis of the infiltrative GC group was poor. There weresignificant differences in the prognosis of the patients betweenthe 2 groups when tumor infiltration was within the muscularlayer or subserosa, yet the differences disappeared once the tumorinfiltration was beyond the serosal layer. The prognosis of thepatients with localized GC was closely related to tumor locationand lymph node metastasis. The prognostic factors of the patientsin the infiltrative GC group included lymph node metastasis,depth of invasion, and tumor *** There are significant differences in theclinicopathologic characteristics and prognosis between the 2groups. Based on the biological characteristics of the tumors,individualized therapeutic plans will help to improve thetreatment outcome.

关键词：肿瘤浸润临床病理预后胃癌患者特征和病理特征气相色谱

High nitrogen stainless steel drug-eluting stent-Assessment of pharmacokinetics and preclinical safety in vivo

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Bioactive Materials 2020年第4期5卷 779-786页

作者： Shanshan Chen zhifeng yao Yongbiao Guan Hui Yang M.Babar Shahzad Yizhe Wu Bingchun Zhang Li Shen Ke Yang Institute of Metal Research Chinese Academy of Sciences72 Wenhua RoadShenyang110016China Shanghai Institute of Cardiovascular Diseases Department of CardiologyZhongshan HospitalFudan University180 Fenglin RoadShanghai200032China National Beijing Center for Drug Safety Evaluation and Research Beijing Institute of Pharmacology and ToxicologyAcademy of Military Medical Sciences27 Taiping RoadHaidian DistrictBeijing100850People's Republic of China

Pharmacokinetic analyses were performed using 20 pigs for 120-days implantation,while one sirolimus-eluting stent was implanted into one of their coronary *** different time points,the residual sirolimus on the stent,delivered locally(to artery wall),regionally(to adjacent and downstream muscle)and systemically(to plasma and visceral organs),was detected throughout 120 *** safety evaluation was performed using 32 pigs for 180-days implantation to study the safety of metal platform material and the effectiveness of sirolimus eluting coating on the HNS *** neointima area,restenosis rate and inflammatory grade for HNS and control group stents were detected and *** 80%sirolimus was eluted from the sirolimuseluting stents after 30-days implantation in ***,there was sustained sirolimus in the artery wall,cardiac muscle and heart throughout 120-days implantation,and sirolimus accumulated to the peak at 90-days *** was inferred that the sirolimus eluting stent in this study was covered by neointima before 90-days implantation,indicating that the sirolimus eluting coating on the HNS stent was safe and *** little sirolimus was distributed in visceral organs after 14-days *** sirolimus-eluting stent exhibited lower restenosis rate and lower inflammatory grade than control group,which verified that the sirolimus-eluting coating design in this study was reasonable and *** addition,there were no significant difference in restenosis rate and inflammatory score between HNS bare-metal stent and drug-eluting stents,illustrating that HNS has good bio-compatibility and is suitable to use as coronary artery stent material.

关键词： Sirolimus-eluting stent Pharmacokinetics Preclinical safety Tissue response

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基于嵌套网格的对称水翼流致振动数值模拟

北京理工大学学报 2023年第9期43卷 885-894页

作者：姚志峰邹圣可曾永顺刘宝熙张佳云中国农业大学水利与土木工程学院北京100083 北京市供水管网系统安全与节能工程技术研究中心北京100083 清华大学能源与动力工程系北京100084

在锁频工况下,水力机械叶片/导叶涡激振动幅值急剧增强,可达到非锁频工况时幅值百倍量级.以对称水翼为研究对象,基于嵌套网格的分离式双向流固耦合计算策略,开展了锁频和非锁频工况下流致振动的数值模拟.结果表明,锁频工况,水翼呈扭转振... 详细信息

在锁频工况下,水力机械叶片/导叶涡激振动幅值急剧增强,可达到非锁频工况时幅值百倍量级.以对称水翼为研究对象,基于嵌套网格的分离式双向流固耦合计算策略,开展了锁频和非锁频工况下流致振动的数值模拟.结果表明,锁频工况,水翼呈扭转振型,尾迹区涡脱落展向呈同相位平行脱落;非锁频工况,水翼以拍频形式振动.预测得到的锁频与非锁频区水翼振动振幅的相对差异与实验情况基本一致,可为大变形工况下的振动特性评估提供指导.

关键词：涡激振动嵌套网格水翼锁频振幅

荜茇明碱诱导乳腺癌MDA-MB-231细胞凋亡的实验研究(英文)

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The Chinese-German Journal of Clinical Oncology 2013年第7期12卷 319-325页

作者： zhifeng yao Jianxin yao Xia He Zhanfeng Li Yongbiao Liu Department of Radiation Oncology The First Affiliated Hospital of Nanjing Medical University Department of Medical Imaging Nanjing Health School of Jiangsu Union Technical Institute Department of Radiation Oncology The Affiliated Cancer Hospital of Nanjing Medical University

Objective: The aim of the study was to investigate the apoptosis induced by piperlongumine on human breast adenoma MDA-MB-231 cells and the mechanism involved. Methods: Human breast adenoma MDA-MB-231 cells line was cultured in vitro. The inhibitory effect of piperlongumine on the proliferation of human breast adenoma MDA-MB-231 cells was measured by CCK-8 assay. Distribution of cell cycle was analyzed by flow cytometry. The apoptosis rates of MDA-MB-231 cells were measured using Annexin V/PI staining. The flow cytometry with the probe of DCFH-DA was used to detect the intracellular reactive oxygen species levels. Western blot was used to explore the protein expression of Bcl-2 and Bax. Results: The CCK-8 assay showed that piperlongumine had an inhibiting effect on the proliferation of MDA-MB-231 cells in a concentrationand time-dependent manner. MDA-MB-231 cells were markedly arrested at G0/G1 phase after treatment of piperlongumine. Piperlongumine induced apoptosis of MDA-MB-231 cells obviously. The level of intracellular reactive oxygen species was increased in a dose-dependent manner. The antioxidant N-acetyl-L-cystein inhibited the apoptosis of cells and the level of intracellular reactive oxygen species was also decreased. By Western blot analysis, we found the expression of Bax was up-regulated whereas that of Bcl-2 was down-regulated in a concentration-dependent manner. Conclusion: Piper-longumine possesses a significant function for inhibiting proliferation, arresting cells at G0/G1 phase and inducing apoptosis of MDA-MB-231 cells, which seems to be associated with the increased generation of intracellular reactive oxygen species as well as the down-regulation of Bcl-2 and up-regulation of Bax.

关键词：细胞凋亡诱导凋亡乳腺癌人类流式细胞仪分析 blot分析 Bcl-2 CCK-8