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新型除草剂快杀稗在水田环境中归宿的研究

环境科学学报 1992年第3期12卷 261-267页

作者：王一茹 Crosby D g 农业部环境保护研究所天津300191 美国加州大学Davis分校环境毒理系

快杀稗为新型选择性水田除草剂,正在世界各地实验推广.快杀稗在太阳光下,纯水中稳定,田水中光解较快.在模拟太阳光的紫外光下(即光解反应器内),在灭菌的田水中光解较慢,h_2O_2可大大加快光解速率,主要光解产物为3,7-二氯喹啉.在ph8的水... 详细信息

快杀稗为新型选择性水田除草剂,正在世界各地实验推广.快杀稗在太阳光下,纯水中稳定,田水中光解较快.在模拟太阳光的紫外光下(即光解反应器内),在灭菌的田水中光解较慢,h_2O_2可大大加快光解速率,主要光解产物为3,7-二氯喹啉.在ph8的水中稳定,不易为微生物降解,几乎不与水田底泥结合,且不易挥发.在田间,快杀稗在30天内消解93—99％,其中第一天消解约50％.稻田底泥中快杀稗含量很低.可以推测,快杀稗污染环境的潜在危险性较小.

关键词：快杀稗光解土壤吸附水解

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常用放射性同位素发生器简评

核动力工程 1985年第1期 90-97页

作者：李茂良 ,g.j.依尔哈特 ,R.M.布鲁格

本文主要评述了三个反应堆生产的放射性同位素发生器(99Mo/99mTc、113Sn/113mIn 和115Cd/115mIn)的优缺点和发展前景。对中国放射性同位素发生器的生产提出了建议。

关键词：同位素发生器 90Mo/99mTc 113Sn/113mIn 115Cd/115mIn

TurboDisc MOCVD设备的理论和应用:流体动力学方法(英文)

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发光学报 2001年第S1期22卷 99-102页

作者： Li S Ramer j WalkerR C Fabiano P EMCORE Corporation 145 Belmont Ave.Somerset NJ08873USAEMCORE Corporation145 Belmont Ave.Somerset NJ08873USAEMCORE Corporation145 Belmont Ave.Somerset NJ08873USAEMCORE Corporation145 Belmont Ave.Somerset NJ08873USA

报道了EMCORE公司的旋转盘反应器 ,或TurboDisc反应器 ,这是一种带有旋转盘的立式反应器。衬底片放置在高速旋转的盘上并被加热到合适的生长温度。反应物在初始阶段因高速旋转盘的牵引力被竖直向下地泵入 ,然后偏斜形成一个与衬底片托... 详细信息

报道了EMCORE公司的旋转盘反应器 ,或TurboDisc反应器 ,这是一种带有旋转盘的立式反应器。衬底片放置在高速旋转的盘上并被加热到合适的生长温度。反应物在初始阶段因高速旋转盘的牵引力被竖直向下地泵入 ,然后偏斜形成一个与衬底片托盘平行的流动区域。在“gaNzilla” ,EMCORE公司的一种新型 32 5mm的gaN生产反应器中外延生长了gaN材料。为在蓝宝石衬底上得到高质量的gaN ,采用高的生长压力和高旋转速度 ,可以在这种旋转盘反应器中实现必要的生长条件。还对 p gaN ,IngaN ,IngaN多量子阱 ,以及LED器件进行了类似的实验 ,都能获得最佳的生长条件。

关键词： Ⅲ-Ⅴ族薄膜材料 MOCVD理论流体动力学方法立式旋转盘反应器

乳腺癌18F-FDg PET/CT显像的瘤内异质性纹理特征分析在疗效和预后预测中的作用

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中华核医学与分子影像杂志 2018年第11期38卷 774-774页

作者：唐军 David Molina-garcía Ana María garcía-Vicente julián Pérez-Beteta Mariano Amo-Salas Alicia Martínez-gonzález María jesús Tello-galán Angel Soriano-Castrejón Víctor M.Pérez-garcía 上海交通大学医学院附属苏州九龙医院核医学科 Mathematical Oncology Laboratory (MoLAB) Universidad de Castilla-La Mancha

目的评价局部晚期乳腺癌(LABC)F-脱氧葡萄糖(FDg)PET/CT显像的纹理分析参数在疗效和预后预测中的价值。方法该前瞻性研究包括68例LABC患者,纳入者均有新辅助化疗(NC)指征,并在化疗前行F-FDg PET/CT显像。对乳腺癌穿刺标本依据分子表型... 详细信息

目的评价局部晚期乳腺癌(LABC)F-脱氧葡萄糖(FDg)PET/CT显像的纹理分析参数在疗效和预后预测中的价值。方法该前瞻性研究包括68例LABC患者,纳入者均有新辅助化疗(NC)指征,并在化疗前行F-FDg PET/CT显像。对乳腺癌穿刺标本依据分子表型进行分组[雌激素受体(ER)、孕激素受体(PR)及人表皮生长因子2(hER2)的表达、细胞增殖核抗原Ki-67指数等)],并在NC结束后将患者分为有效组和无效组。所有患者经标准的随访后得到无病生存时间(DFS)和总生存时间(OS)。利用计算机软件对乳腺癌病灶进行三维(3D)图像分割,随后进行纹理特征分析,获得行程长度矩阵(RLM)和共生矩阵(CM)参数。对不同危险度的纹理特征与各种分子表型的关系进行分析。使用Kaplan-Meier生存分析和Cox比例风险分析对纹理参数、分子表型和NC的肿瘤组织学反应等在预测疗效和预后中的作用进行研究。通过受试者工作特征(ROC)曲线分析取得最佳截断值、曲线下面积(AUC)及与OS、DFS相关的灵敏度和特异性。结果 NC对18例患者有效,其DFS和OS分别为(70.87±21.85)个月和(76.77±18.80)个月。长行程增强(LRE)和长行程高灰阶增强(LRhgE)与不同的危险度分层有关,而低灰阶行程增强(LgRE)、LRhgE和行程长度不均匀性(RLNU)均与NC的疗效相关。单因素分析结果表明纹理特征分析各变量与OS和DFS相关。多因素Cox回归分析结果显示,短行程高灰阶强化(SRhgE)下的PET分期与OS相关,而PET分期、高灰阶行程强化(hgRE)均与DFS相关。结论F-FDg PET/CT图像的纹理特征分析各变量可预测新辅助化疗的疗效和预后,并在预测OS和DFS时与PET分期具有相关性。

关键词：乳腺癌 18F-FDg PET/CT 纹理特征新辅助化疗疗效总生存时间无病生存时间

利用16层CT对冠状动脉搭桥术后患者的综合评价

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世界核心医学期刊文摘(心脏病学分册) 2006年第2期 34-35页

作者： Salm L. P. Bax j. j. jukema j. W. 韩瑞娟 Department of Cardiology(C5-P) Leiden University Medical Center PO Box 9600 2300 RC Leiden Netherlands Dr.

Background: Multidetector-row computed tomography(MDCT) is a versatile modality to evaluate stenoses in native coronary arteries and bypass grafts. Acquired MDCT data can additionally be used to assess left ventricular ejection fraction(LVEF). The purpose was to use MDCT for the assessment of bypass graft and coronary artery disease combined with evaluation of LVEF. Methods: Twenty-five patients underwent 16-detector-row CT examination and coronary angiography. Bypass grafts and nongrafted coronary artery segments at MDCT were evaluated on eligibility, patency, and ≥ 50% stenosis. The MDCT data set was used to calculate LVEF and was divided into patients with no/subendocardial/transmural myocardial infarctions(MIs). Results: Ninety vessels were evaluated: 14 arterial grafts/53 vein grafts/23 nongrafted vessels. Of 225 segments, 17 were ineligible for evaluation because of metal clips. With MDCT, patency in segments of arterial grafts/vein grafts/nongrafted vessels could be evaluated with high accuracy in 100% /100% /97% of segments. In arterial grafts, stenoses ≥ 50% did not occur at angiography,which was for all eligible segments correctly diagnosed at MDCT. Stenosis ≥ 50% could be correctly detected by MDCT with a sensitivity/ specificity of 100% /94% for vein grafts and 100% /89% for nongrafted vessels. Negative predictive value was 100% for vein grafts and nongrafted vessels. In patients with transmural MI, MDCT revealed a significant lower LVEF as compared with patients without or with subendocardial MI(Phensive assessment of bypass grafts, nongrafted vessels, and LVEF is feasible with MDCT. Owing to the high negative predictive value this noninvasive approach may be used as gatekeeper before coronary angiography.

关键词： CT 血管桥静脉桥

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在二尖瓣峡部进行线性消融的技术和结果

世界核心医学期刊文摘（心脏病学分册） 2005年第4期1卷 42-42页

作者： j.s P. hocini M. hsu L.-F. 杜媛 hop. haut-Leveque 33604 Bordeaux-Pessac France Dr.

Background -This prospective clinical study evaluates the feasibility and eff icacy of combined linear mitral isthmus ablation and pulmonary vein(PV) isolatio n in patients with paroxysmal atrial fibrillation(AF). Methods and Results -One hundred consecutive patients(13 women; age 55±10 years)-with drug-refractory , symptomatic paroxysmal AF underwent PV isolation and linear ablation of the ca votricuspid isthmus and the mitral isthmus(lateral mitral annulus to the left in ferior PV). They were compared with 100 consecutive patients(14 women; age, 52± 10 years) undergoing PV isolation and cavotricuspid ablation without mitral isth mus ablation. Bidirectional mitral isthmus block was confirmed by demonstrating( 1) a parallel corridor of double potentials during coronary sinus(CS) pacing,(2) an activation detour by pacing either side of the line, and(3) differential pac ing techniques. Isolation of all PVs and cavotricuspid isthmus ablation were per formed successfully in all. Mitral isthmus block was achieved in 92 patients aft er 20±10 minutes of endocardial radiofrequency application and an additional 5 ±4 minutes of epicardial radiofrequency application from within the CS in 68, r esulting in a conduction delay of 151±26 ms during CS pacing. Thirty-two patie nts with mitral isthmus ablation compared with 49 without had recurrent atrial a rrhythmia (P=0.02) requiring further ablation. At 1 year after the last procedur e, 87 patients with mitral isthmus ablation and 69 without(P=0.002) were arrhyth mia free without antiarrhythmic drugs, mitral isthmus ablation being the only fa ctor associated with long-term success(RR for AF recurrence, 0.2; CI, 0.1 to 0. 4; Pheter ablation of the mitral isthmus results cons istently in demonstrable conduction block and is associated with a high cure rat e for paroxysmal AF.

关键词：二尖瓣峡部线性消融起搏技术阵发性房颤抗心律失常药物射频消融术传导阻滞分离术冠状窦和阵