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21.
22.
Wang Tao Liang Zhihou Sun Shenggang Cao Xuebing Peng Hai Cao Fei Liu Hongjin Tong E-tang 《华中科技大学学报(医学英德文版)》2003,23(2):145-147
Summary To investigate the distribution of possible novel mutations from parkin gene in variant subset of patients with Parkinson’s
disease (PD) in China and explore whether parkin gene plays an important role in the pathogenesis of PD, 70 patients were
divided into early-onset group and late-onset group; 70 healthy subjects were included as controls. Genomic DNA from 70 normal
controls and from those of PD patients were extracted from peripheral blood leukocytes by using standard procedures. Mutations
of parkin gene (exon 1–12) in all the subjects were screened by PCR-single strand conformation polymorphism (SSCP), and further
sequencing was performed in the samples with abnormal SSCP results, in order to confirm the mutation and its location. A new
missense mutation Gly284Arg in a patient and 3 abnormal bands in SSCP electrophoresis from samples of another 3 patients were
found. All the DNA variants were sourced from the samples of the patients with early-onset PD. It was concluded that Parkin
point mutation also partially contributes to the development of early-onset Parkinson’s disease in Chinese.
WANG Tao, male, born in 1961, Associate Professor
This work was supported by grants from the key program of the special scientific project of Scientific & Technologic Agency
of Hubei Province (Serial No. 2001AA308B01) and the Hygienic Research Project of Hygienic Agency of Hubei province (Serial
No. WJ 01529). 相似文献
23.
痛力克对癌症疼痛镇痛效果的临床观察 总被引:1,自引:0,他引:1
应用印度LUPIN公司提供的痛力克(酮酷酸氨丁三醇 )对中重度癌症疼痛30例进行镇痛效果的临床观察,有效率93%,平均显效时间9min,均数缓解时间5.1h,并用哌替啶做了同期交叉自身镇痛对比研究,结果表明:两药的镇痛效果相似(P>0.05),但痛力克的不良反应发生率明显低于哌替啶。 相似文献
24.
Influence of mild hypothermia on vascular endothelial growth factor and infarct volume in brain tissues after cerebral ischemia in rats 总被引:1,自引:0,他引:1
BACKGROUND: It has been demonstrated that mild hypothermia has obvious protective effect on both whole and local cerebral ischemia. However, the definite mechanism is still unclear for the brain protection of mild hypothermia on cerebral edema, inhibiting inflammatory reaction, stabilizing blood brain barrier, etc.
OBJECTIVE: To investigate the effect of mild hypothermia on the expression of vascular endothelial growth factor and the infarct volume after cerebral ischemia in rats, and analyze the brain protective mechanism of mild hypothermia.
DESIGN: A randomized grouping and controlled animal trial.
SETTING: Department of Neurology, People's Hospital of Yunyang Medical College.
MATERIALS: Twenty adult male SD rats of clean degree, weighing (250±30) g, were provided by the animal experimental center, School of Medicine, Wuhan University. The kits for SP immunohistochemistry were purchased from Beijing Zhongshan Golden Bridge Biotechnology Co., Ltd.
METHODS: The experiments were carried out in the laboratory of Department of Neurology, Renmen Hospital of Wuhan University from May to July 2005. ① The 20 rats were divided randomly into normal temperature group (n =10) and mild hypothermia group (n =10). Models of permanent middle cerebral artery occlusion were established with modified nylon suture embolization. The rats were assessed with the Longa standards: 0 point for without nerve dysfunction; 1 for mild neurological deficit (fore claws could no extend completely); 2 for moderate neurological deficit (circling towards the affected side); 3 for severe neurological deficit (tilting towards the affected side); 4 for coma and unconscious; 1-3 points represented that models were successfully established. The rats of the normal temperature group were fed at room temperature, and those in the mild hypothermia group were induced by hypothermia from 2 hours postoperatively, and the rectal temperature was kept at 34-35 ℃ for 72 hours. ② Measurement of infarct volume: All the rats were anesthetized by intraperitoneal injection overdose sodium pentobarbital 7 days postoperatively, and then the heads were cut down to harvest brain. The brain tissues were placed into -20 ℃ refrigerator for 20 minutes, coronal sections of 2 mm were prepared. The infarct sites were not stained, whereas normal brain tissues were stained as red. The infarct volumes were calculated by using MPLAS-500 multimedia color pathological image&&word analytical system. ③ Counting positive cells of vascular endothelial growth factor protein: The brains were harvested by cutting heads, then coronal sections of 2 mm were prepared. Routine dehydration, hyalinization, wax immersion and embedding were performed, then the detected with SP immunohistochemistry, the kits were purchased from Beijing Zhongshan Golden Bridge Biotechnology Co., Ltd. The cells whose cytoplasm was yellow-brown were positive ones, a single sample as a unit, peri-ischemic site and ischemic core were selected, and the corresponding sites in controlateral hemisphere were taken as controls. Five visual fields were selected from each site to be observed under microscope, the cells were counted, and the average number of positive cells was calculated in each group. The numbers of positive cells were determined with the image analytical apparatus.
MAIN OUTCOME MEASURES: Number of the positive cells of vascular endothelial growth factor protein; Infarct volume of rat brain tissue.
RESULTS: All the 20 rats were involved in the analysis of results. ① Number of positive cells of vascular endothelial growth factor protein in brain tissue: It was obviously lower in the mild hypothermia group than in the normal temperature group [(24.02±5.05), (36.07±2.69) cells/high power visual field, P < 0.01]. ② Comparison of infarct volume of brain tissue: After MCAO, it was obviously smaller in the mild hypothermia group than in the normal temperature group [(153.25±23.14), (253.45±36.21) mm3, P < 0.01].
CONCLUSION: Mild hypothermia can inhibit the expression of vascular endothelial growth factor and decrease the volume of cerebral infarction. The inhibition of mild hypothermia on the expression of vascular endothelial growth factor may be one of the brain protective mechanisms. 相似文献
25.
胰腺实性-假乳头状瘤影像与病理诊断分析 总被引:29,自引:0,他引:29
目的 探讨胰腺实性-假乳头状瘤的影像及病理学的诊断要点。资料与方法 回顾分析11例经手术切除、病理学和免疫组织化学证实的胰腺实性一假乳头状瘤患者的临床资料,以比较其影像和病理学特点。结果 (1)本病多发于30岁以下女性,临床主要表现为腹痛。(2)CT、MRI表现为肿瘤内有实性和囊性结构,可分为3型;特征性表现为“浮云征”。(3)肿瘤大部分位于胰腺,多有完整包膜,不伴有胆总管扩张。(4)病理学特点为肿瘤实性部分由实性区、假乳头区及两者过渡区以不同比例混合而成。囊性区由坏死、液化、陈旧性出血组成。(5)肿瘤的囊实性结构是形成“浮云征”的病理基础。结论 胰腺实性-假乳头状瘤有相对特征性的影像和病理学表现,术后预后较好。 相似文献
26.
27.
医科院校师生对考试现状看法的调查与分析 总被引:2,自引:0,他引:2
医科院校的考试主要是学科考试。调查显示,教师和学生对目前的学科考试模式评价均不高,存在的最主要弊端是考试方法单一,考试管理不够科学、严谨,考风不好;认为作弊的主要原因在于学生自己学习不努力、社会风气影响以及学校对教师和学生要求不够严格。因此,要搞好考试改革,提高考试质量,必须着重从改革考试方法、加强考试管理的改革与研究、整顿考风、制定科学的成绩评定方法、加强能力考核、实施教考分离等方面进行探索与实践。 相似文献
28.
30余种氨基酸、40余种非挥发性有机酸和20余种碱基核苷类化合物在一块薄层板上完成多相同步色谱分析;用紫外灯-吖啶试剂-镉茚三酮试剂实行组合显色定位分析。改善了尿液中非挥发性有机酸的溶剂萃取法,尿中三类化合物提取物的同步多相色谱分离效果良好。 相似文献
29.
30.
甲硫氨酸脑啡肽对抗体的产生和T细胞免疫功能具有调节作用。为了明确这种作用机制,本实验观察了抗体和白细胞介素-2(IL-2)的产生和基因表达。甲硫氨酸脑啡肽对3F3杂交瘤细胞的抗体产生及其轻链和重链基因表达影响不明显。较高浓度的甲硫氨酸脑啡肽(0.1nmol·L ̄(-1)-1μmol·L(-1))不仅促进IL-2的产生和IL-2mRNA的转录,而且能提高IL-2mRNA的稳定性。 相似文献