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61.
We report a rare chronic encapsulated intracerebral haematoma (CEICH). A 52-year-old man had two seizures. Unenhanced computed tomography scanning of the head revealed a hypodense tumour with clusters of calcification in the left temporal lobe. Magnetic resonance imaging of the brain showed a left temporal tumour with a hypointense centre and hyperintense periphery on T(1)-weighted imaging and heterogeneous hypointensity on T(2)-weighted imaging. The tumour was heterogeneously enhanced after gadolinium injection. Craniotomy was carried out and a CEICH in the left temporal lobe was completely excised. No vascular anomaly was found. The tumour was histologically confirmed to be a CEICH. The patient recovered well after the operation. In this report, we describe this rare case and discuss the characteristics of CEICH. 相似文献
62.
目的 近年来产生了一些用于分析基因表达数据的聚类算法,却很少有关于评价聚类算法方法的研究。本研究的目的是尝试建立一个定量的评价基因表达数据聚类结果的方法。方法 本研究提供了一个系统的评价聚类结果的方法,利用我们提出的实验均方误差F值对几个常见的聚类算法进行比较。结果 利用F值对类质量的评价和利用已有的生物学知识对类进行分析的结果一致。结论 实验均方误差F值可以定量地评判用于基因表达数据的聚类算法。 相似文献
63.
64.
通过本次流行病学调查和实验研究,发现须恙螨主要分布于肾综合征出血热流行区,其地理分布与疫区的病例分布基本一致。主要传染源黑线姬鼠鼠体带螨指数为25.1;从鼠肺抗原阳性鼠体所采集的须恙螨幼虫和小黑板采集经叮刺吸食已感染本病病毒的小白鼠乳鼠体液后的游离螨幼虫,分别分离到1株病毒,证明须恙螨具备传播媒介的先决条件。 相似文献
65.
66.
药物构效关系研究与药物设计中常用计算机软件 总被引:3,自引:0,他引:3
分子力学、量子化学和分子图形学是研究有机药物分子电子特性、空间性质及其与受体相互作用的有力工具。现扼要介绍国内外较常用的量子化学和分子力学及分子图形学有关计算机程序的应用特性。 相似文献
67.
You M. Lu Bu F. Lu Yu L. Yan Tin H. Yan Xiaon P. Ho Wen J. Wang 《The European journal of neuroscience》1993,5(10):1334-1338
The activation of membrane-associated phospholipase C is rapidly and transiently induced in the central nervous system by a variety of stimuli. Ischaemic brain injury is one of the situations that leads to a dramatic increase in polyphosphoinositide (PPI) turnover. In this study, stimulation of PPI hydrolysis by glutamate (500 μM) was measured in hippocampal slices from rats up to 21 days after an ischaemic insult of 30 min. Ischaemia was induced using the four-vessel occlusion method. PPI hydrolysis elicited by glutamate was significantly increased in the slices prepared from ischaemic rats 24 h after reperfusion, the accumulation of inositol phosphates (InsPs ) and inositol 1,4,5-trisphosphate (InsP3 ) was 614±74% ( n = 8) and 182±11% ( n = 9) of the basal level respectively. This potentiation was also observed 21 days after ischaemia. Hyper-responsiveness to glutamate was also accompanied by an increase in AIF− 4 -stimulated formation of [3 H]inositol phosphates. In addition, global ischaemia did not change either high-affinity [3 H]glutamate binding in hippocampal membranes or the stimulation of PPI hydrolysis by carbachol or noradrenaline in hippocampal slices. The present results suggest that the increased responsiveness to glutamate is the result, at least in part, of functional changes at the G-protein level, and may contribute to the pathophysiology of ischaemic brain injury or to the regenerative phenomena that accompany ischaemic damage. 相似文献
68.
目的探讨粤西沿海地区季节气候与妇科门诊常见感染(细菌性、念珠菌性、滴虫)疾病的相关性.方法以妇科白带涂片多项检查快速染色技术(CTB)对妇科门诊就诊的7 042例患者做阴道分泌物常规检查,分春、夏、秋、冬季4组统计分析.结果春夏秋冬四季妇科门诊患者阴道分泌物的念珠菌检出率比较,差异有高度显著性(P<0.01);细菌检出率无季节性差异(P>0.05);滴虫检出率比较,亦无差异(P>0.05).结论粤西地区妇科门诊病例念珠菌检出率受气候差异影响,夏秋季节明显高于冬春季节;而细菌和滴虫检出率则不受气候差异影响. 相似文献
69.
Ming-I. Hsu Paul Kolm John Leete Ke Wen Dong Suheil Muasher Sergio Oehninger 《Journal of assisted reproduction and genetics》1998,15(8):496-503
Purpose:
Our purpose was to examine implantation of singleton pregnancies achieved following various assisted reproductive technologies (ARTs) through the appearance and rising titers of serum human chorionic gonadotropin (hCG) levels.
Methods:
A total of 114 singleton pregnancies resulting from in vitro fertilization and intrauterine insemination was analyzed. Patients were divided into five groups according to the type of ovarian stimulation protocol [gonadotropin stimulation with/without the use of gonadotropin-releasing hormone agonist (GnRHa), long protocol, or flare-up technique] and to the day of embryo transfer (day 2 or day 3 after oocyte retrieval). Serial serum hCG levels were measured between 10 and 25 days after fertilization and log-transformed. Linear regression analyses were performed and extrapolated to hCG = 10 mIU/ml (hCG
10
), which was used as an estimate of detectable implantation. The slopes of the regression lines were used to estimate the rising speed of hCG.
Results:
There were no significant differences in the days of hCG in maternal serum to reach 10 mIU/ml (implantation) or in the slopes of the regression lines for all five studied groups.
Conclusions:
The appearance of hCG in maternal serum was used to assess the time of clinically detectable implantation. Furthermore, because hCG production is a marker of trophoblastic activity, its serum doubling time was used as an indicator of embryo quality. Results showed that in various ART protocols with and without GnRHa, there were no significant differences in implantation time or embryo quality. Embryo development in early pregnancy follows a preprogrammed-timing schedule and depends mainly on the embryonic age of the health, successfully implanted conceptus. 相似文献
70.
M. Wen-Der Yun C. F. Hwang C. C. Lui 《European archives of oto-rhino-laryngology》1991,248(7):422-424
Summary Cavernous sinus thrombosis (CST) is rarely seen clinically as a complication of infectious processes since the discovery of penicillin. At the present time, dental abscess is an uncommon cause of CST. We now report our experiences with a 60-year-old diabetic male, who developed CST 38 days after extraction of an infected upper third molar tooth. The importance of eradicating regional cervicofacial foci of infection is stressed. 相似文献