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排序方式: 共有10000条查询结果,搜索用时 46 毫秒
41.
目的:介绍实验性小鼠膜性肾小球肾炎(MGN)的复制方法,并探讨其免疫荧光定量分析在肾小球肾炎研究中的应用价值。方法:制备阳离子化牛血清白蛋白(GBSA)并复制小鼠MGN,对各组小鼠进行电镜及免疫荧光观察,并进行免疫荧光定量研究。结果:电镜、免疫荧光观察均显示病理Ⅰ组(PⅡ组)具有典型的MGN病变,病理Ⅱ组(PⅡ组)病变轻微且不典型。免疫荧光定量研究证实PⅠ、PⅡ组与对照组差异有显著性;PⅠ、PⅡ组间差异无显著性。结论:C—BSA可作为复制小鼠MGN的良好抗原,隔日2mg/只尾静脉注射4w即可复制出稳定的小鼠MGN模型。免疫荧光定量分析不仅能直接而准确地反映MGN病理变化,而且在MGN早期即具有诊断价值。 相似文献
42.
Genetic contributions to Parkinson's disease 总被引:8,自引:0,他引:8
Sporadic Parkinson's disease (PD) is a common neurodegenerative disorder, characterized by the loss of midbrain dopamine neurons and Lewy body inclusions. It is thought to result from a complex interaction between multiple predisposing genes and environmental influences, although these interactions are still poorly understood. Several causative genes have been identified in different families. Mutations in two genes [α-synuclein and nuclear receptor-related 1 (Nurr1)] cause the same pathology, and a third locus on chromosome 2 also causes this pathology. Other familial PD mutations have identified genes involved in the ubiquitin–proteasome system [parkin and ubiquitin C-terminal hydroxylase L1 (UCHL1)], although such cases do not produce Lewy bodies. These studies highlight critical cellular proteins and mechanisms for dopamine neuron survival as disrupted in Parkinson's disease. Understanding the genetic variations impacting on dopamine neurons may illuminate other molecular mechanisms involved. Additional candidate genes involved in dopamine cell survival, dopamine synthesis, metabolism and function, energy supply, oxidative stress, and cellular detoxification have been indicated by transgenic animal models and/or screened in human populations with differing results. Genetic variation in genes known to produce different patterns and types of neurodegeneration that may impact on the function of dopamine neurons are also reviewed. These studies suggest that environment and genetic background are likely to have a significant influence on susceptibility to Parkinson's disease. The identification of multiple genes predisposing to Parkinson's disease will assist in determining the cellular pathway/s leading to the neurodegeneration observed in this disease. 相似文献
43.
目的对FKBP6基因第3、4外显子进行突变和多态性筛查,研究第3外显子278C/A位点及第2内含子C/T位点(rs7797242)在无精症患者和正常男性中的多态性,初步探讨与原发无精症的相关性。方法采用变性高效液相色谱和聚合酶链反应-限制性片段长度多态性方法,对第3、4外显子进行突变和多态性筛查,对177例无精症患者和231名正常男性的278C/A和C/T(rs7797242)多态性进行基因分型。结果278C和278A等位基因频率符合Hardy-Weinberg平衡。无精症患者278A显著低于正常对照,差异有统计学意义(P<0.05)。C/T多态性在两组中均未检出,第3、4外显子未筛查到新的变异。结论278A等位基因可能与原发无精症相关。C/T(rs7797242)及370G/A,430G/C,467T/C,468G/A在中国人群中非常罕见。 相似文献
44.
45.
中国汉族人群腓骨肌萎缩症Cx32基因突变分析 总被引:7,自引:0,他引:7
Charcot Marie Tooth (CMT)diseaseisthemostcommoninheritedperipheralneuropathywithapreva lenceof 1in 2 5 0 0 .Distalmuscleweaknessandatro phy ,sensorylossandreducedorabsenttendonreflex es ,pescavus ,hammertoes ,steppagegaitareamongthemainsymptoms .Thereares… 相似文献
46.
M van der Neut Kolfschoten R J Dirven S R Poort R van Wijk H L Vos F R Rosendaal R M Bertina 《Journal of thrombosis and haemostasis》2004,2(6):910-917
BACKGROUND: During the study of a family with hereditary factor (F)V deficiency (FV Amersfoort, 1102 A > T in exon 7) we identified an individual with 5% FV heavy chain antigen (FV(HC)) and 50% FV light chain antigen (FV(LC)). Further testing revealed that apart from the FV Amersfoort allele a second variant FV allele was segregating in this family, which encodes for a FV molecule with a reduced affinity for mAb V-23 used in the FV heavy chain ELISA (ELISA(HC)). OBJECTIVE: Identification and characterization of the molecular basis responsible for the reduced affinity of the variant FV for mAb V-23. METHODS: Family members of the proband were screened for mutations in the exons coding for the heavy chain of FV, after which the recombinant variant FV could be generated and characterized. Next, the cases and controls of the Leiden Thrombophilia Study (LETS) were genotyped for carriership of the variant FV. RESULTS: In the variant FV allele a polymorphism in exon 3 (409G > C) was identified, which predicts the replacement of aspartic acid 79 by histidin (D79H). Introduction of this mutation in recombinant FV confirmed that it reduces the affinity for binding to mAb V-23. The substitution has no effect on FV(a) stability and Xa-cofactor activity. In Caucasians the frequency of the FV-79H allele is approximately 5%. Analysis of the LETS revealed that the FV-79H allele is not associated with FV levels (FV(LC)), activated protein C sensitivity (using an activated partial thromboplastin time-based test) or risk of venous thrombosis (OR 1.07, CI 95: 0.7-1.7). CONCLUSION: The D79H substitution in FV should be considered as a neutral polymorphism. The monoclonal antibody V-23, which has a strongly reduced affinity for FV-79H, is not suitable for application in diagnostic tests. 相似文献
47.
The association of MTHFR and CBS variants with the doubling time and responsiveness to several chemodrugs was analyzed in 26 human cancer xenografts. The tumors homozygous for the absence of insertion (NN) for the CBS 844ins68bp were more chemosensitive than those with insertion (NI) to TS-1 (P=0.0048), suggesting a potential effect of this variant on fluoropyrimidine efficacy. Furthermore, the doubling time of tumors with a variant C allele (AC or CC) in MTHFR-A1298C was significantly longer than that of tumors with a normal allele (AA) (P=0.0008). Twenty-nine cellular proliferation-related genes were associated with MTHFR-A1298C genotyping and with the doubling time. 相似文献
48.
It is well known that migraine has a strong genetic component, although the type and number of genes involved remains unclear. There is evidence to suggest that serotonin-related genes may be involved in the pathogenesis of migraine. To investigate whether the 5-HT1A receptor gene contributes to the risk of migraine we performed an association study of C-1019G promoter polymorphism of the gene in 102 migraineurs and 93 controls. Subjects were of Han Chinese origin. No significant differences in allele (P=0.82) or genotype frequencies (P=0.71) were seen in migraineurs compared with the controls. When migraine with aura, without aura, with family history, without family history were analyzed separately, the frequencies did not vary significantly. Our results suggest that C-1019G in 5-HT1A is not a major genetic risk factor for migraine. 相似文献
49.
深部脑白质缺血影像表现与MTHFR基因多态性关系的探讨 总被引:1,自引:0,他引:1
目的:探讨MTHFR的纯合突变TT型基因是否为诱发皮层下深部脑白质缺血的危险因子,并证实皮层下深部脑白质缺血影像表现与MTHFR基因C/T多态性的关系。资料与方法:选择影像表现符合皮层下深部脑白质缺血诊断标准者30例,对照组30例为影像表现正常者,运用多聚酶链反应-限制性内切酶片段长度多态性技术(PCR-RFLP)检测两组MTHFR基因多态性。结果:采用χ^2检验,得出MTHFR基因纯合突变TT型在病变组与对照组比较差异有显著性(χ^2=5.0794,P<0.05),病变组TT型较对照组显著升高,说明MTHFR的纯合突变TT型可能是诱发深部脑白质缺血的危险因素。运用成组设计两样本比较的秩和检验,得出TT型和非TT型患者在影像表现的分级程度上有差别,携带TT型基因者影像表现分级重。结论:MTHFR纯合突变TT型基因是深部脑白质缺血发病的危险因子,且TT型基因与深部脑白质缺血的易感性和影像表现呈明显正相关。 相似文献
50.
It has been suggested that reward dependence, as measured by the Tridimensional Personality Questionnaire (TPQ), is related to central noradrenergic activity, a proposition supported by two studies of urinary norepinephrine metabolite. In the current investigation, 190 normal young Han Chinese were examined, with genetic polymorphisms determined for the norepinephrine transporter (1287G/A) and the α2c‐adrenoceptor (Del322–325) to test the association with TPQ personality traits. No significant association was demonstrated for these two polymorphisms and any of the TPQ personality‐factor scores, including reward dependence and its subscales. Our negative findings suggest that the investigated polymorphisms of the norepinephrine transporter and the α2c adrenoceptor do not play a major role in the reward‐dependence personality trait as assessed by TPQ. © 2002 Wiley‐Liss, Inc. 相似文献