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991.
Kensei Minoda 《眼科学报》1996,(1)
Purpose: To disclose the structure of visual pigment gene for a protanopia with specific variation.Methods: Exon 5 fragments of the red andgreen visual pigment genes from the protanopia with specific varnation as well as controls were amplified by poly-merase chain reaction (PCR). The PCR products were put through heteroduplex-SSCP analysis and PCR-RFLP (restriction fragement length polymorphism) analysis to clarify the specific variation. The specific variation of the exon 5 DNA fragment from the protanopia was identified by sequencing.Results: A novel 5'green-3'red hybrid gene fragment without the normal red and green visual pigment gene was discovered in the protanopia. He should only have a single visual pigment gene, 5'green-3'red hybrid gene, on his X chromosome. The fusion point is between codon 285 and codon 296 in exon 5. Conclusion : Unequal intragenic recombination may occur in exon 5 as well as its upstream. A 5'green-3'red hybrid gene may present independently on the X chromosome without ac 相似文献
992.
特发性肌炎免疫机制研究及临床意义 总被引:4,自引:1,他引:3
目的探讨多发性肌炎(PM)和皮肌炎(DM)患者骨胳肌组织损伤的免疫机制及临床意义。方法应用免疫荧光一步法和免疫组化SP法分析25例PM/DM肌组织中免疫球蛋白IgG、IgM、补体C3和浸润肌组织单核细胞的分布与定位。结果PM和DM肌组织中IgG、IgM、C3的阳性率分别为60%、33.3%、20%和70%、40%、50%,以IgG为主(P<0.05),分布于肌组织血管壁、肌膜和肌浆中,补体C3在DM血管壁的分布有统计学意义(P<0.05);80%PM和7O%DM肌组织有单核细胞浸润,PM以T淋巴细胞为主,Ia+活化TS细胞占多数,主要分布于肌内衣,DM以B淋巴细胞为主,多分布在肌柬衣血管周围。结论免疫反应在PM和DM发病机理中占重要地位,PM以T细胞介导的细胞毒作用为主,DM以体液免疫特别是补体介导的血管损害为主。 相似文献
993.
用不同剂量尿烷一次腹腔注射,对KM、BALB/c和A/J系小鼠进行肺肿瘤短期诱导试验,以比较其敏感性,为环境化学物致癌性鉴定的实验条件提供依据。结果显示:以肺肿瘤发生率和平均发瘤数两项指数来衡量发瘤危险,A/J系均在最低染毒剂量(25mg/kg)即出现发瘤危险明显增高;KM系以发生率衡量时,100mg/kg为发瘤危险增高的最低剂量,而以平均发瘤数衡量时,最低剂量为200mg/kg;BALB/c系前 相似文献
994.
Eighteen Coopworth ewe lambs were divided into three groups based on the initial cystourethrogram and cystometry findings
at 5 – 7 weeks of age: group 1, 6 lambs with spontaneous low-pressure bilateral vesicoureteric reflux (VUR) on bladder filling
were used to study the natural history of reflux; group 2, 5 lambs with no VUR detected were used to establish an experimental
model of bilateral VUR using an unroofing surgical procedure; group 3, 7 lambs with spontaneous VUR detected during micturition
had the same surgical procedure to increase the degree of VUR. All three animal groups were followed for 4 – 10 months. Spontaneous
VUR was demonstrated in 13 of 18 lambs (25/36 ureters). The presence and severity of spontaneously occurring reflux in group
1 lambs diminished with increasing age. VUR was created successfully in group 2 and increased in degree in group 3 animals.
The only significant histological finding in all three animal groups with grades II and III VUR was distal renal tubular dilatation.
The sheep is a useful and readily available animal for studying VUR. During 4 – 10 months of follow-up, sterile reflux without
bladder outflow obstruction resulted in distal renal tubular dilatation, but no renal parenchymal damage.
Received April 17, 1997; received in revised form August 5, 1997; accepted August 21, 1997 相似文献
995.
Ivan Bednar Xiao Zhang Ramez Dastranj-sedghi Agneta Nordberg 《International journal of developmental neuroscience》1998,16(7-8):661-668
The basal forebrain cholinergic neurons are implicated in the pathogenesis ofneurodegenerative diseases including Alzheimerfn2s disease (AD). The nicotinic acetylcholine receptors (nAChRs) have been found to besignificantly afflicted in AD. To study the underlying mechanisms for dysfunction of the basalforebrain cholinergic neurons development of suitable animal models is warranted. In this studywe investigated the effects of bilateral lesions of the nucleus basalis magnocellularis on nAChRs inthe rat brain using the cholinergic system selective immunotoxin 192-IgG saporin andnon-selective excitotoxin ibotenic acid. Changes in nAChRs were measured by 3H-cytisineand 3H-epibatidine, two ligands with different selectivity for nAChRs subtypes. Inthe parietal cortex of ibotenic acid lesioned rates, the choline acetyltransferase activity (ChAT)was decreased by 24% while no changes were detected in the frontal cortex or hippocampus.Similarly, a 40% decrease was observed in the number of nAChRs labelled by 3H-cytisine,but not by 3H-epibatidine, in the parietal cortex, while no changes were found in thefrontal cortex or hippocampus. Although the 192-IgG saporin induced lesions reduced the ChATactivity in the frontal cortex, parietal cortex and hippocampus by 77, 50 and 21%, respectively, nochanges were observed in the number of nAChRs as studied by 3H-cytisine or 3H-epibatidine. The results indicate a difference in vulnerability of the cortical nAChRsubtypes to experimental lesions of the nucleus basalis magnocellularis. The findings in this studysuggest that a major portion of the nAChRs might be located on non-cholinergic neurons in thebrain. 相似文献
996.
用荧光法研究^ωN-硝基左旋精氨酸(L-NNA)对大鼠脑缺血后大脑皮层、海马、纹状体和小脑中一氧化氮(NO)的变化,结果显示L-NNA可明显减少缺血10min不同脑区NO的含量(P〈0.05或P〈0.01);左旋精氨酸可部分逆转L-NAA的使用,使NO的含量增加(P〈0.05或P〈0.01)。提示L-NAA可减少脑缺血时NO的过量生成而具有潜在的治疗作用。 相似文献
997.
成人特发性乳糖酶缺乏症的发生率极高,这些人进食牛奶后会出现胃肠胀气、腹痛、腹泄等对牛奶不耐受的消化不良症状。为解决这一问题,自1989年起,国内外不少学者是主张有产替代疗法,即将人工培养制备纯化的乳糖酶直接加入牛奶中以水解其中的乳糖来弥补成人乳糖酶的缺乏。 相似文献
998.
介绍了香港环保署通过10年努力的完整的固体废弃物收运,处理及处置系统,以及他们为实现废弃物减量化和资源化所采取的策略与行动。由此提出上海浦东新区在固体废弃物管理和环卫设施建设上应加强关注;逐步按规划实施;采用多种形式设计,建造,营运环卫设施以及开展全方位宣传教育活动的建议。 相似文献
999.
1000.
用联大茴香胺法测定大白鼠血清中铜蓝蛋白的活力,大白鼠体外血清在旋磁场中曝磁30分钟后,血清铜蓝蛋白活力增加,而大白鼠整体血清在旋磁场中曝磁30分钟后,血清铜蓝蛋白活力无明显变化。 相似文献