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991.
目的:探讨视网膜下腔注射视黄酸对视网膜变性发展的阻断作用。方法:14d龄视网膜色素变性鼠(retinal degeneration mouse,Rd鼠)各8只视网膜下腔分别注射10^-3,mol/L浓度视黄酸和磷酸盐缓冲液(phosphate buffered saline,PBS),术后1个月对注射眼进行病理取材。并取7、14、28d和3个月龄Rd鼠各3只作正常对照。结果:视网膜下腔注射视黄酸和PBS,1个月后均可见部分眼视网膜内核层细胞增殖,视网膜下腔注射视黄酸较注射PBS未见有明显差异。结论:通过视网膜下腔注射视黄酸并不能使已经变性的视网膜恢复正常或阻断视网膜变性的发展。 相似文献
992.
Purpose: To investigate changes in the production of tissue inhibitor of metalloproteinase type 1 (TIMP-1) by human retinal pigment epithelial (RPE) cells following argon laser exposure. Methods: Human cultured ARPE19 cells were exposed to argon green laser at four different energy levels ranging from 60mW to 360mW. After laser exposure, the culture media were sampled at 0, 24, 72 and 144 hours for TIMP-1 concentration produced by the RPE cells. The levels of TIMP-1 in the cells treated with different laser energy levels were compared with a control group not exposed to laser application. Immunocytochemistry for proliferating cell nuclear antigen (PCNA) was performed to detect any adverse effects on the RPE cells caused by laser exposure. Results: Immediately after laser exposure, the concentration of TIMP-1 was not detectable. At 24 hours after laser exposure, the concentration of TIMP-1 increased significantly in RPE cells treated with 120mW and 240mW at 24 hours (P=0.006 and P=0.001 respectively) comp 相似文献
993.
青蒿琥酯对大鼠肝星状细胞增殖的影响 总被引:1,自引:0,他引:1
目的:探讨青蒿琥酯抗肝纤维化的作用机制。方法:用MTT法观察青蒿琥酯对HSC增殖的影响,用流式细胞仪检测HSC在细胞周期中DNA含量的改变,测定不同浓度青蒿琥酯作用于HSC后上清液中Hpy、LDH的含量。结果:1.5~100μg/m l青蒿琥酯在0~72h范围内对HSC增殖有抑制作用,并有药物浓度时间依赖关系。各青蒿琥酯处理组中G0/G1期细胞比例逐渐增高,与正常组相比由56.2±1.3%升至72.6±2.3%左右;S期比例逐渐降低,由27.1±2.6%降至13.8±4.1%左右,而对G2/M期无影响。青蒿琥酯(12.5μg/m l~100μg/m l)组上清液Hyp值逐渐减小,呈剂量依赖关系,与相应的空白对照组比较有显著性差异;青蒿琥酯组上清液LDH与空白对照组比较无显著性差异。结论:青蒿琥酯能阻止HSC从G0/G1期进入S期,体外能明显抑制HSC的增殖,减少胶原的分泌,且在实验观察剂量范围内对HSC没有细胞毒性。 相似文献
994.
目的:探讨丹参针剂和限制门静脉血流对大鼠极限性肝叶切除(90%)后早期残肝损害的效应。方法:按Gaub的方法建立大鼠90%极限性肝叶切除模型,分别观察限制门静脉血流和加用丹参对大鼠手术后死亡率,残肝HE染色肝细胞中央静脉及汇管区的改变以及术后血生化的改变。结果:限制门静脉血流能减轻早期极限性肝叶切除后残肝的损害,加用丹参后能进一步减轻损害,但均不能改善实验动物的死亡率。结论:限制门静脉血流能减轻早期极限性肝叶切除后残肝的损害,加用丹参后能进一步减轻,但并不能引发残肝细胞再生的启动而延长动物的存活。 相似文献
995.
Jones W Bellugi U Lai Z Chiles M Reilly J Lincoln A Adolphs R 《Journal of cognitive neuroscience》2000,12(Z1):30-46
Studies of abnormal populations provide a rare opportunity for examining relationships between cognition, genotype and brain neurobiology, permitting comparisons across these different levels of analysis. In our studies, we investigate individuals with a rare, genetically based disorder called Williams syndrome (WMS) to draw links among these levels. A critical component of such a cross-domain undertaking is the clear delineation of the phenotype of the disorder in question. Of special interest in this paper is a relatively unexplored unusual social phenotype in WMS that includes an overfriendly and engaging personality. Four studies measuring distinct aspects of hypersocial behavior in WMS are presented, each probing specific aspects in WMS infants, toddlers, school age children, and adults. The abnormal profile of excessively social behavior represents an important component of the phenotype that may distinguish WMS from other developmental disorders. Furthermore, the studies show that the profile is observed across a wide range of ages, and emerges consistently across multiple experimental paradigms. These studies of hypersocial behavior in WMS promise to provide the groundwork for crossdisciplinary analyses of gene-brain-behavior relationships. 相似文献
996.
Serotonin is implicated in the pathogenesis of schizophrenia. Following serotonin release, the serotonin transporter (5-HTT) is the major determinant of serotonin inactivation. The present study tested the hypothesis that a biallelic polymorphism in the 5' regulatory region of the 5-HTT gene (5-HTTLPR) confers susceptibility to schizophrenia, association with the clinical manifestations of schizophrenia or clozapine response. 90 treatment-resistant schizophrenic patients were assessed using the Brief Psychiatric Rating Scale before and after clozapine treatment. The results demonstrated that the 5-HTTLPR variants did not play a major role in the susceptibility, clinical manifestations or clozapine response in schizophrenia. 相似文献
997.
目的 评价紫杉醇联合顺铂治疗晚期鼻咽癌的临床疗效和毒副反应。方法 28例晚期局部复发或/和远处转移性鼻咽癌患者采用紫杉醇175mg/m^2,静脉滴注持续3h,第1天给药;DDP30mg/m^2,静脉滴注,第2~4天。21d为1周期,2周期后评价疗效。结果 全组均可评价,CR3例,PR15例。有效率(RR)为64.28%,主要毒副反应为骨髓抑制,周围神经炎,消化道反应,肌肉及关节痛,脱发等。结论 紫杉醇联合顺铂治疗晚期局部复发或/和远处转移性鼻咽癌有较高疗效,毒副反应较小,值得临床进一步研究。 相似文献
998.
Association study of apolipoprotein E epsilon4 with clinical phenotype and clozapine response in schizophrenia 总被引:2,自引:0,他引:2
Schizophrenic patients with the apolipoprotein E (APOE = gene; apoE = protein) epsilon4 allele exhibited lower psychosis scores than patients without the epsilon4 allele in previous reports. The present study tested the hypothesis that the APOE epsilon4 allele confers association with the clinical manifestations of schizophrenia or clozapine response. A total of 95 schizophrenic patients who were treatment resistant were included in the study. The results demonstrated that the presence of the APOE epsilon4 allele did not influence the response to clozapine in schizophrenic patients, neither was the baseline psychopathology related to the APOE epsilon4 allele. Given the multiple functions of the apoE protein in the brain, further study of the influence of APOE on CNS medication response is needed. 相似文献
999.
目的:研究青蒿琥酯抗实验性肝纤维化的作用。方法:采用牛血清白蛋白免疫性肝纤维化大鼠模型,观察肝组织病理变化,检测肝组织中羟脯氨酸的含量及动物血清肝功能指标和血清MDA水平。结果:青蒿琥酯组能减轻假小叶形成和肝组织羟脯氨酸含量升高,并能使GPT下降。结论:青蒿琥酯具有抗肝纤维化的作用。 相似文献
1000.
Yih‐Ju Yang Tzu‐Hsien Liag Song‐Hsiung Lin Hsin‐Cheng Chen Shih‐Chan Lai 《Clinical & experimental optometry》2006,89(1):40-44
A 62‐year‐old woman presented with unilateral eye swelling and itching. Subsequent examination showed the cause was an infestation of the parasitic worm Thelazia callipaeda. The vector leading to human infection is the fly. The possible mechanisms of infection for this patient are discussed. Although this is a known form of ocular infection, especially in Asia, this is one of few reported cases in Taiwan. 相似文献