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21.
Transformation of a Drosophila virilis white mutant host strain was attempted using a hobo vector containing the D. melanogaster mini-white+ cassette (H[w+, hawN]) and an unmodified or heat shock regulated hobo transposase helper. Two transformant lines were recovered with the unmodified helper (HFL1), one containing only the white+ marked vector, and a sibling line containing the vector as well as an HFL1 helper integration. An approximate total transformation frequency of 1% is deduced. A high frequency of wing and eye morphology mutants were also observed, suggesting that hobo may have mobilized a related element in D. virilis. The data reaffirms a relatively low transformation vector activity for the hobo transposon in D. virilis; however, nearly full interspecific expression of the white+ marker supports its possible function in other species as well.  相似文献   
22.
杨元  肖翠英  张思仲  张思孝  黄明孔  林立 《四川医学》2004,25(11):1166-1168
目的 探讨Y染色体无精症因子C区(azoospermia factor C,AZFe)无精症缺失基因(deleted-in-azoospermia,DAZ)家族基因拷贝缺失与中国男性原发不育之间的关系。方法 运用多重PCR与PCR-RFLP检测技术,对210例已生育男性、216例原发无精症与189例严重少精症患者Y染色体AzFc区域DAZ基因家族的基因拷贝数进行分析。结果 在所有已生育男性中未检出DAZ基因拷贝的完全或部分缺失,而在原发无精症与严重少精症患者中DAZ基因拷贝完全缺失率分别为8.8%和12.2%,DAZ1/DAZ2共缺失率分别为8.3%和5.3%。结论 在中国男性原发无精症与严重少精症患者中存在较高频率的DAZ基因拷贝缺失现象,提示Y染色体AZFc区域DAZ基因家族基因拷贝的完全与部分缺失是中国男性原发不育的遗传高风险因子。  相似文献   
23.
目的:观察枳鳖胶囊抗肝纤维化形态学和Ⅲ型胶原mRNA表达的变化。方法:选择66只健康清洁级SD大鼠,雌雄各半,随机分为:正常对照组,模型组,秋水仙碱组,枳鳖胶囊大、中、小剂量组。以40%四氯化碳花生油皮下注射结合高脂饲料、酒水饮料复合因素诱导大鼠肝纤维化模型。造模结束后,除正常组不予处理外,其他组分别以蒸馏水,秋水仙碱混悬液,高、中、低浓度枳鳖胶囊溶液灌胃,疗程36d。疗程结束后,观察大鼠新鲜肝脏的表面情况、色泽、质地等大体形态,测定肝组织Ⅲ型胶原mRNA的表达,光镜观察肝组织HE染色和网状纤维染色的病理形态学改变。结果:模型组大鼠肝细胞损害、肝脏脂肪变性和胶原纤维增生的程度最显著,Ⅲ型胶原mRNA的表达最强。枳鳖胶囊组上述改变明显减轻,且可抑制Ⅲ型胶原mRNA的表达,疗效优于秋水仙碱组。结论:枳鳖胶囊可较好地保护肝细胞,并能阻止肝纤维化进程甚或逆转肝纤维化病理改变,抑制胶原基因表达,抑制胶原基因表达可能是其抗肝纤维化的作用机理之一。  相似文献   
24.
25.
Twenty-two members of 18 families with autism have been examined for the presence of mutations and abnormal methylation in the FMR-1 region at Xq27.3. All patients fulfilled diagnostic criteria of infantile autism. A characteristic pattern of insertion and methylation were detected after Southern blot analysis in 7 autistic individuals expressing the fragile site at Xq27.3. Normal DNA patterns were observed in 15 autistic boys cytogenetically negative for the fragile site. The results indicate a lack of involvement of the FMR-1 region in infantile autists negative for fragile X expression. © 1992 Wiley-Liss, Inc.  相似文献   
26.
The external subdivision of the lateral parabrachial nucleus (LPBE) shows strong Fos-like immunoreactivity (FLI) following anorectic doses of the indirect serotonin agonist dexfenfluramine (DFEN). In an effort to determine the contribution of the LPBE to DFEN-induced anorexia, bilateral ibotenate lesions were made in the LPBE, and the effects of the lesion on DFEN-induced anorexia and FLI as well as c-June-like immunoreactivity (JLI) were examined. It was found that LPBE lesion significantly attenuated DFEN anorexia: in a 1-h food intake test following 24-h food deprivation, DFEN (2 mg/kg) suppressed food intake by 60% in intact rats but only 34% in rats with LPBE lesions. In addition to this behavioral change, LPBE lesion completely abolished DFEN-induced FLI and JLI in the lateral subdivision of the central nucleus of the amygdala (CeL) and laterodorsal subdivision of the bed nucleus of stria terminalis (BSTLD), both of which showed strong FLI and JLI in intact rats. DFEN-induced FLI and JLI in other brain regions were not affected by LPBE lesion, including the ventromedial and lateral hypothalamus, caudate-putamen, and the nucleus of the solitary tract (NST). The parallel loss of DFEN-induced anorexia and FLI/JLI following LPBE lesion raises the novel possibility that LPBE-CeL/BSTLD pathway may be involved in DFEN anorexia.  相似文献   
27.
用免疫组织化学ABC法,研究了降钙素基因相关肽(CGRP)免疫反应神经纤维在大鼠胆总管末端与十二指肠连接处的分布。大鼠的胆总管末端有较丰富的CGRP免疫反应神经纤维,它们多呈串珠(膨体)状,少数为无膨体的细长纤维。CGRP-IR纤维主要分布肌层及血管周围,在神经纤维的附近可见到含CGRP-IR阳性颗粒的肥大细胞。本实验为神经免疫调节机制的研究提供了形态学依据。  相似文献   
28.
Oral hairy leukoplakia is an epithelial lesion of the tongue associated with productive infection by Epstein-Barr virus (EBV). However, no data concerning the pattern of EBV latent gene expression have been reported, and it remains unresolved whether true latent infection occurs in basal cell layers of oral hairy leukoplakia. We have studied six cases of oral hairy leukoplakia using monoclonal antibody immunohistology for EBV latent--EB nuclear antigen (EBNA) 1, EBNA 2 and latent membrane protein 1 (LMP 1); immediate-early (BZLF1); and replicative (EA, VCA, MA) proteins, and for the EBV-receptor (CD21 antigen). EBV DNA was demonstrated by nucleic acid in situ hybridization. Mid- to upper-zone keratinocytes contained EBV DNA and co-expressed EBNA 1, EBNA 2 (5 of 6 cases), LMP 1, BZLF1 protein, EA, VCA and MA. No EBV genome or gene expression could be demonstrated in basal or parabasal cells. Spinous keratinocytes were labelled by anti-CD21 antibodies HB5 and B2, but did not express the EBV-receptor as defined by reactivity with OKB7. The co-expression of latent and replicative infection-associated antigens is striking, indicating possible functional roles for latent proteins during the productive cycle. Our results suggest that oral hairy leukoplakia is caused by repeated direct infection of upper epithelial cells with virus from saliva or adjacent replicatively infected cells, rather than by a latent EBV infection of basal epithelial cells with a differentiation-dependent switch to productive infection as previously proposed.  相似文献   
29.
The knee meniscus exhibits extensive spatial variations in native healing capacity, biochemical composition, and cell morphology that suggest the existence of distinct phenotypes for meniscus cells. Constitutive gene expression levels of appropriate extracellular matrix proteins may serve as useful molecular markers of cellular phenotypes; however, relatively little is known of variations in the gene expression for meniscus cells of different regions of the tissue. The objective of the present study was to evaluate constitutive differences between radial inner and outer regions in gene expression for extracellular matrix proteins relevant to the meniscus. A secondary objective was to determine if these region-specific differences in gene expression are maintained after periods of monolayer culture. The innermost regions of the meniscus were found to constitutively express higher mRNA levels for proteins highly expressed in articular cartilage, including aggrecan, type II collagen, and NOS2. In contrast, the outer meniscus was found to contain higher gene expression for proteins associated with fibrous tissues including type I collagen, and the proteases MMP2 and MMP3. Isolated inner and outer meniscus cells maintained these region-specific gene expression patterns for collagens and proteoglycans during short-term monolayer culture. The results provide new information that suggests the utility of constitutive gene expression levels as molecular markers to distinguish tissue and cells of the inner and outer meniscus.  相似文献   
30.
Frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP‐17) is a hereditary progressive neurodegenerative disorder. FTDP‐17 was originally defined in Ann Arbor, Michigan, in 1996. Since then, more than 100 families with FTDP‐17 have been described throughout the world, including 18 families identified in Japan. Genetic studies have identified 40 different mutations in the microtubule‐associated protein tau (MAPT) gene. The clinical features of FTDP‐17 are characterized by behavioral, cognitive and motor disturbances that may occur in various combinations and degrees. Neuropathologic examination shows that various degrees of atrophy may be present in the frontal and temporal lobes, basal ganglia, amygdala and hippocampus. All the brains from patients with FTDP‐17 have also shown the presence of tau deposits in neurons and glial cells. Mutations in MAPT may result in the increased splicing of exon 10, leading to 4‐repeat tau depositions in both neurons and glial cells. MAPT mutations outside of exon 10 show 3‐ and 4‐repeat tau deposits, predominantly in neurons with less glial pathology. Neuronal pathology may resemble that of Alzheimer’s disease or Pick’s disease because of the presence of neurofibrillary tangles or Pick‐like bodies, whereas glial pathology may resemble that of progressive supranuclear palsy or corticobasal degeneration because of the presence of coiled bodies, tufted astrocytes or astrocytic plaques. Correlations between genetic mutations and the heterogeneity of clinical and neuropathologic features remain unclear.  相似文献   
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