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单绒毛膜双羊膜腔双胎的不对等胎盘分配和出生体重差别

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世界核心医学期刊文摘（妇产科学分册） 2006年第10期2卷 9-10页

作者： Fick A.L. Feldstein v.A. Norton m.E. 张新艳 Department of Obstetrics Gynecology and Reproductive Sciences University of California San Francisco CA United States Dr.

Objective: The purpose of this study was to define the association between unequal placental sharing and birth weight discordance in monochorionic/diamniotic twin pregnancies. Study design: The study comprised a prospective cohort of monochorionic/diamniotic twin pregnancies who were delivered in Kaiser Permanente-Northern California, 1997-2003. Dye injection studies of fresh postpartum placentas were performed. Placental sharing, cord insertion combinations, vascular anastomoses, gestational age, and birth weights were recorded. Statistical comparisons of birth weight and gestational age were made with the Student t test. Rates of birth weight discordance were compared with the chi-square test. multivariate logistic regression models analyzed the relationship between variables of interest. Results: mean birth weights for larger and smaller twins were 2400 g and 2109 g, respectively. Twenty-two percent of the monochorionic/diamniotic twin pairs had birth weight discordance ≥20%, and 8%of these pairs had twin-twin transfusion syndrome. monochorionic/diamniotic twin pairs with unequal placental sharing had a 9.8 times greater likelihood of birth weight discordance(95%CI, 5.4-17.9) as compared with those pairs with equal placental sharing. Conclusion: Unequal placental sharing is a significant risk factor for birthweight discordance inmonochorionic/diamniotic twins. Antenatal diagnosis of unequal placental sharing would enable improved counseling in the setting of monochorionic/ diamniotic twins.

关键词：单绒毛膜羊膜腔出生前诊断产前咨询北加利福尼亚血管吻合前瞻性队列研究回归模型分析统计学

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配筋砌体抗弯及抗剪承载力的计算

石油石化节能与计量 1998年第5期 45-46页

作者：杜峰,戴悦,P．B.Shing,m.Schuller,v.S.Hoskere 天津大学土木系天津市建筑设计研究院

配筋砌体要承受重力荷载、风荷载和水平地震作用。虽然配筋砌体的设计方法不同于钢筋混凝土结构，但后者的某些设计思路却仍适用于配筋砌体结构。对砌体来说，由斜裂缝引起的剪切破坏比由抗弯钢筋屈服后导致的弯曲破坏脆性要大。因而要... 详细信息

配筋砌体要承受重力荷载、风荷载和水平地震作用。虽然配筋砌体的设计方法不同于钢筋混凝土结构，但后者的某些设计思路却仍适用于配筋砌体结构。对砌体来说，由斜裂缝引起的剪切破坏比由抗弯钢筋屈服后导致的弯曲破坏脆性要大。因而要尽量控制砌体的破坏形态为弯曲破坏而非剪切破坏。本文以试验为基础，提出配筋砌体抗弯承载力及抗剪承载力的计算方法。

关键词：配筋砌体抗弯承载力抗剪承载力试验

心脏mRI评价急性心肌梗死后微血管阻塞和预测近期重塑的研究

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国际医学放射学杂志 2009年第2期32卷 184-185页

作者： R.Nijveldt m.B.m.Hofman A.Hirsch A.m.Beek v.A.W.m.Umans P. R.Algra 范丽 Department of Cardiology VU University Medical Center

目的探讨何种评价微血管阻塞的心脏mRI技术能够最佳地预测急性心肌梗死后左室的重塑。方法本研究经当地伦理委员会同意且所有病人签署了知情同意书。63例首发急性心肌梗死病人经支架植入和最佳临床治疗后分别在发病后第4～7天和4个... 详细信息

目的探讨何种评价微血管阻塞的心脏mRI技术能够最佳地预测急性心肌梗死后左室的重塑。方法本研究经当地伦理委员会同意且所有病人签署了知情同意书。63例首发急性心肌梗死病人经支架植入和最佳临床治疗后分别在发病后第4～7天和4个月进行了心脏电影mRI检查。

关键词：急性心肌梗死后微血管阻塞 mRI评价心脏预测 mRI技术知情同意书最佳临床治疗

新发的成年起病且病因不明的难治性、局灶性癫痫持续状态的外科治疗效果

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世界核心医学期刊文摘(神经病学分册) 2006年第10期 12-13页

作者： Costello D.J. Simon m.v. Eskandar E.N. 郭俊 Epilepsy Service Department of Neurology VBK 830 Massachusetts General Hospital 55 Fruit St Boston MA 02114 United States Dr.

Background: There have been few published reports of successful surgical treatment of focal status epilepticus. Surgical intervention is considered a last resort after medical strategies have been exhausted. Objective: To report a case of an adult who was initially seen with de novo, medically refractory, cryptogenic focal status epilepticus and underwent resection of an electrographically defined portion of the left middle frontal gyrus with multiple subpial transections of the adjacent cortex resulting in termination of the electroclinical seizure activity. Design: Report of a case of successful surgical treatment of cryptogenic focal status epilepticus. Intervention: After an initial 35 days of oral antiepileptic drug therapy and subsequent 16 days of continuous electroencephalography- guided intravenous antiepileptic drug therapy in an intensive care unit setting, and after extensive preoperative and intraoperative characterization of the epileptogeniczone, a tailored resection of the left middle frontal gyrus with multiple subpial transections of the surrounding cortex was performed. Results: The restricted surgical resection and multiple subpial transections terminated the seizure activity. Neuropathological examination of the resected tissue revealed moderate inflammatory changes and a few abnormally located neurons without any definitive evidence of dysplasia, which was suspected preoperatively. Conclusions: We suggest that focal cortical resection may be an appropriate intervention in medically refractory focal status epilepticus even when an overt structural etiology is not evident preoperatively and should be considered as an option at the onset of intractability.

关键词：持续状态癫痫脑病局灶性难治性外科治疗

极低出生体重儿经鼻连续气道正压通气早期失败的相关因素

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世界核心医学期刊文摘（儿科学分册） 2006年第2期2卷 26-27页

作者： Ammari A. Suri m. milisavljevic v. R.A. Polin 郭战宏 Department of Pediatrics College of Physicians and Surgeons Columbia University 3959 Broadway BHS-115 New York NY 10032-3702 United States Dr.

Objective: To identify risk factors and neonatal outcomes associated with the early failure of “ bubble” nasal continuous positive airway pressure (CPAP) in very low birth weight (vLBW) infants with respiratory distress syndrome (RDS)-. Study design: Following resuscitation and stabilization at delivery, a cohort of 261 consecutively inborn infants (birth weight ≤ 1250 g) was divided into three groups based on the initial respiratory support modality and outcome at 72 hours of age: “ ventilator-started” group, “ CPAP-failure” group, and “ CPAP-success” group. Results: CPAP was successful in 76% of infants ≤ 1250 g birth weight and 50% of infants ≤ 750 g birth weight. In analyses adjusted for postmenstrual age (PmA) and small for gestational age (SGA), CPAP failure was associated with need for positive pressure ventilation (PPv) at delivery, alveolar-arterial oxygen tension gradient (A-a DO2) >180 mmHg on the first arterial blood gas (ABG), and severe RDS on the initial chest x-ray (adjusted odds ratio 95% CI = 2.37 1.02, 5.52 , 2.91 1.30, 6.55 and 6.42 2.75, 15.0 , respectively). The positive predictive value of these variables ranged from 43% to 55% . In analyses adjusted for PmA and severe RDS, rates of mortality and common premature morbidities were higher in the CPAP-failure group than in the CPAP-success group. Conclusion: Although several variables available near birth were strongly associated with early CPAP failure, they proved weak predictors of failure. A prospective controlled trial is needed to determine if extremely premature spontaneously breathing infants are better served by initial management with CPAP or mechanical ventilation.

关键词：极低出生体重儿气道正压通气早期经鼻呼吸窘迫综合征 CPAP 相关危险因素呼吸支持方式动脉血气分析小于胎龄

LASER HEAT TREATING RESEARCH OF THREE KINDS OF HIGH SPEED STEEL

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Acta metallurgica Sinica(English Letters) 1999年第5期12卷 757-760页

作者： Liu, W.N. Fang, m.N. Xing, J. Liu, Y.W. Changchun Inst of Optics and Fine Mechanics Changchun China

After laser quenching and tempering of three kinds of annealed tool high-speed steel(W18Cr-4v, W9mo3Cr4v1, W6mo5Cr4v2) test samples, the microhardness measurer was used to test the samples and some problems, such as the hardness and depth of hardening-quenching layer were analyzed. Furthermore, after laser quenching and tempering of the quenched and three-time tempered high-speed steel (W18Cr4v) and its hardness analyzing, different results of laser-quenching samples were obtained under different initial heat-treating.

关键词： Hardening Heat treatment Laser beam effects microhardness Phase transitions Quenching

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黄土边坡可靠度的随机有限元分析

地球科学与环境学报 2019年第1期41卷 116-126页

作者：李萍白健忠 GRIFFITHS D v 李同录郑亚楠长安大学地质工程与测绘学院陕西西安710054 Department of Civil and Environmental Engineering Colorado School of Mines 天水金泉矿业有限公司西安分公司陕西西安710065

为了研究黄土边坡的可靠度,在对黄土强度参数进行变异性统计、概率分布检验及垂直向自相关距离计算的基础上,将黄土强度参数黏聚力和内摩擦角作为随机变量,将其在二维边坡剖面的空间变化作为随机场,用局部平均细分法将符合一定均值和标... 详细信息

为了研究黄土边坡的可靠度,在对黄土强度参数进行变异性统计、概率分布检验及垂直向自相关距离计算的基础上,将黄土强度参数黏聚力和内摩擦角作为随机变量,将其在二维边坡剖面的空间变化作为随机场,用局部平均细分法将符合一定均值和标准差的强度参数按随机场分布在边坡剖面的有限元网格上,再采用弹-理想塑性有限元计算边坡稳定系数,用monteCarlo法计算其失效概率。结果表明:黄土黏聚力的变异系数多在0.30以上,内摩擦角的变异系数多在0.20以下,且黄土高原从西向东两个参数的变异性都增大;黏聚力和内摩擦角的概率分布类型对边坡失效概率计算结果影响显著,统计检验发现黏聚力采用对数正态分布、内摩擦角采用正态分布为宜;黄土地层的垂直向自相关距离多在0.7m以内,与计算厚度的比值多小于0.2;在大部分黄土的变异系数与自相关距离水平下,采用确定场进行可靠度分析,多数情况将极大地高估了黄土边坡的失效概率,而在极端高变异系数水平下,采用确定场进行可靠度分析,又将极大地低估其失效概率。

关键词：黄土边坡随机场有限元黏聚力内摩擦角自相关距离可靠度稳定系数

幼年性结肠息肉综合征患者的结肠手术:一组病例研究

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世界核心医学期刊文摘（胃肠病学分册） 2005年第10期1卷 14-15页

作者： Oncel m. Church J.m. Remzi F.H. Fazio v.W. 郝筱倩 Cleveland Clinic Foundation 9500 Euclid Avenue A30 Cleveland OH 44195 United States Dr.

PURPOSE: Juvenile polyposis syndrome is characterized by multiple hamartomatous polyps in the large intestine. When indicated, the surgical choices in symptomatic juvenile polyposis syndrome patients are colectomy with ileorectal anastomosis or proctocolectomy with pouch. The aim of this study was to evaluate the long-term outcomes of the surgical options in juvenile polyposis syndrome patients who present with symptomatic colonic polyps. mETHODS: The charts of all juvenile polyposis syndrome patients who had had at least one colonic operation since 1953 in our institution were reviewed. The following data were abstracted: demographics, the number and site of the polyps, symptoms, the intervals and types of the colonic operation, follow-up, and the patients’current status. RESULTS: There were 13 patients (6 males) with a median age of 10 years (range, 1-50 years) at the time of diagnosis. Patients had colonic (n = 13), rectal (n = 12), and gastric (n = 6) polyps. Rectal bleeding (n = 11) was the most common presenting symptom. Three patients underwent proctectomy as the initial operation. Although a rectum-preserving operation was initially performed in ten patients, a subsequent proctectomy was required in five of them within a median of 9 years (range, 6-34 years). Therefore, eight patients had their rectum removed during the study period; five had an ileal pouch-anal anastomosis, one had a Koch pouch as a restorative surgery, and two had an end ileostomy. No relation was observed between the number of colonic and rectal polyps and the type of surgery or the need for proctectomy. Patients were followed up a median of 3 years (range, 2-24 years) after their ultimate operations. During this period, one patient (20 percent) who underwent restorative proctectomy and 4 patients (80 percent)-whose rectums were preserved required multiple endoscopic polypectomies for recurrent polyps in the pouch (first patient)-or their rectums (the other four patients). The patient who

关键词：肠息肉综合征幼年性结肠手术病例研究回肠直肠吻合术直肠切除术回肠袋末端回肠造口术结肠袋肛门直肠

A comparison between different ohmic contacts for ZnO thin films

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Journal of Semiconductors 2015年第3期36卷 41-45页

作者： Shadia J.Ikhmayies Naseem m.Abu El-Haija Riyad N.Ahmad-Bitar AlIsra University Faculty of Information Technology Department of Basic Sciences-Physics Physics Department Faculty of Science University of Jordan

There are several metals that form ohmic contacts for ZnO thin films, such as copper, aluminum and silver. The aim of this work is to make a comparison between these ohmic contacts. To achieve this purpose, polycrystalline ZnO thin films were prepared by the spray pyrolysis technique, and characterized by the I-v.m.asurements at room temperature. Two strips of each metal were thermally evaporated on the surface of the film and measurements were first recorded in the dark and room light, then in the dark before and after annealing for A1, which was found to be the best in the set. Films with aluminum contacts gave the smallest resistivity, best ohmicity and they are slightly affected by light as required. On the other hand, copper was found to be the worst, and films with copper contacts gave the largest resistivity, worst ohmicity and they are the most affected by light. Annealing improved the aluminum contacts due to alloying and doping.

关键词： transparent conducting oxide ohmic contacts annealing solar cells