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61.
In primary visual cortex of hooded rats, pyramidal cells in layer V may be classified as long, medium, or short, on the basis of the layer in which the apical dendrite terminates. The present study determines which of these types of pyramidal cells project to the superior colliculus. Two different strategies were used to label corticotectal cells with horseradish peroxidase (HRP). In the first set of experiments, a large number of corticotectal cells were labeled by retrograde transport following injection of HRP into the superior colliculus. In the second set of experiments, single unit recording was used to identify corticotectal cells physiologically by antidromic activation from the superior colliculus. These cells were then impaled and labeled by intracellular iontophoresis of HRP. The results from both techniques suggest that only long pyramidal cells send an axon to the superior colliculus. These cells are distinguished by an apical dendrite that extends into layer I. We conclude that in hooded rats corticotectal cells in primary visual cortex are the long pyramids in layer V. 相似文献
62.
Summary This study was undertaken to elucidate, using the Golgi method, the neuropathological change in the brain of the macular mutant mouse, whose hemizygote (Ml/y) is considered to be a model of Menkes kinky hair disease (MKHD). The hemizygote mice gradually lost weight after 10 days of age and died with emaciation and seizure around day 15. The normal littermate (+/y) was well developed. In the cerebrum, the arborization of pyramidal neurons in the layer V of the Ml/y was the same as that in the +/y on day 10. However, development of arborization in the Ml/y was delayed in comparison with that in the +/y on days 12 and 14. Purkinje cells with several somal sprouts were observed in the cerebellum in both the Ml/y and +/y on day 7. The somal sprouts in the +/y had regressed gradually by day 12, while they were still in the anterior and middle lobes of the Ml/y on day 14. Additionally, the trunks of Ml/y stem dendrites became thicker and a cactus formation was recognized on the branching portion of the dendrites on day 14. Arborization of these abnormal Purkinje cells was distinctly poor compared with that in the +/y. These results suggest that the growth of the neurons is delayed in the Ml/y and simultaneously their cytoskeletal developments are disturbed, especially in the Purkinje cells. There is a close similarity in many respects to the neuropathological change in MKHD. 相似文献
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65.
Objective To predict the HLA class Ⅰ restricted cytotoxic T lymphocyte epitopes for human proliferating cell nuclear antigen (PCNA). Methods By using 3 epitope prediction databases which including MHC binder ( BIMAS and SYFPEITHI databases) and proteasome cutting site ( PAProC databases), the epitopes of PCNA were predicted by analyzing several parameters and methods. Results After comprehensive analysis,we have obtained two possible HLA-A0201 restricted CTL epitopes SMSAD-VPLV (228-236, score 447 633. 595 ) and LINEACWDI ( 22-28, score 127 966.779);two HLA-A24 re-stricted CTL epitopos DYEMKLMDL ( 113-121, score 563 994.9 ) and EFARICRDL ( 143-151, score 40 540.7);two HLA-A1101 restricted CTL epitopes LTSMSKILK (72-80, score 1334. 2680 ) and DVPLV-VEYK (232-240,score 736.9236). Conclusion The multi-parameter epitope prediction method is feasi-ble for cytotoxic T lymphocyte epitope prediction. 相似文献
66.
目的 初步建立阴道粘膜上皮细胞体外培养方法,为阴道粘膜上皮研究提供实验模型.方法 取雌性新西兰大白兔阴道粘膜组织小块,胶原酶Ⅳ和胰蛋白酶联合消化分离法收集上皮细胞,接种于角朊细胞无血清培养液中静置培养、传代.动态观察细胞生长增殖情况,扫描和透射电镜观察超微结构,流式细胞仪测定细胞增殖周期,并进行免疫组织化学鉴定.结果 体外培养的阴道粘膜上皮细胞为二倍体细胞,增殖状态良好,细胞间可见桥粒连接,免疫组化角蛋白染色阳性.细胞的超微结构和免疫组化染色均具有上皮细胞特征.结论 在本实验条件下,体外培养的阴道粘膜上皮细胞具有较好的增殖能力,可作为阴道粘膜上皮研究的理想实验模型. 相似文献
67.
评估控制性卵巢刺激中预测卵巢反应性的指标 总被引:1,自引:0,他引:1
在辅助生育技术的实施中,控制性卵巢刺激(COS)方案是根据患者情况确定的,在用药剂量和启动时间的掌握上非常重要。由于卵巢本身反应性或基础状态的不同,不同年龄及不同病因的患者有着极大的差异,用量适当可避免因启动剂量过大造成卵巢过度剌激(OHSS),或剂量过少造成低反应,卵泡 相似文献
68.
荷人卵巢癌严重联合免疫缺陷鼠腹腔移植模型的建立 总被引:1,自引:0,他引:1
目的 :建立荷人卵巢癌细胞株 SKOV3严重联合免疫缺陷小鼠 (SCID)动物模型。方法 :SCID鼠腹腔注射人 SKOV3卵巢癌细胞 1× 10 7个 /只 ,饲养在无特定病原体环境中 ,观察其生物学特性。结果 :实验组 3只 SCID小鼠腹腔内均见肿瘤生长 ,并形成以横膈、肠系膜、肝周、腹膜为主的转移灶 ,其中 1只肺部有镜下转移灶。移植后肿瘤细胞在形态、生长、分泌 CA12 5功能方面均与原细胞株保持一致。结论 :建立的荷人 SKOV3卵巢癌 SCID鼠腹腔移植模型能较好地模拟人卵巢癌腹腔播散的生物学特征。 相似文献
69.
Objective: To further explore the mechanism of congenital pyrimidine 5'-nucleotidase I deficiency. Methods; The samples were collected from the family members of a patient with P5'N- I deficiency. The enzyme activities were measured by UMP method and the enzyme proteins were quantified by ELISA while the morphology of peripheral blood cells was observed. Results: The enzyme contents reduced as their enzyme activities decreased in the family especially in four members. There was a significant positive correlation(r =0. 955) between the activity and the content of P 5'N- I . The count of the stippling cell was varied in the family. Conclusion.- One of the reasons for congenital P5' N- I deficiency might be the deficiency in the enzyme content. The morphology of peripheral blood erythrocyte may be an assistant diagnotic index. The P5'N- I activities and contents were measured simultaneously may be a effective method in clinic diagnosis. 相似文献
70.
目的 评价子宫动脉栓塞术治疗子宫肌瘤的近期疗效。方法 89例子宫肌瘤患者,采用Seldinger技术分别作左右子宫动脉主干插管检查和栓塞治疗,栓塞剂采用聚乙稀醇颗粒(PVA)或白芨混合颗粒。结果 72例(80.9%)完成随访,随访时间1~28个月。有94.1%(64/68)的患者月经复常;治疗后瘤体缩小25.2%~76.8%(M=41.3%)。除了术中术后疼痛(65例)和发热(16例)外,有2例因肌瘤坏死行子宫切除术,1例出现卵巢早衰。结论 子宫动脉栓塞术治疗子宫肌瘤的近期疗效满意,远期疗效尚待进一步观察。 相似文献