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81.
目的:了解黏膜相关淋巴瘤的凋亡水平及其所涉及到的信号传导通路。方法:收集33例胃肠黏膜相关淋巴样组织(MALT)淋巴瘤病例,通过TUNEL技术原位检测MALT淋巴瘤肿瘤细胞的凋亡水平,通过逆转录聚合酶链反应(RT-PCR)和免疫组织化学染色检测肿瘤的凋亡抑制蛋白2编码基因(API2)和Caspase3 mRNA及蛋白,对API2和Caspase3水平作半定量和定量分析。根据凋亡检测结果将全部病例分为两组,即凋亡细胞数每50个高倍视野小于或等于2的病例组和大于2的病例组,比较2组的API2和Caspase3 mRNA及蛋白。结果:半数以上的MALT淋巴瘤中存在凋亡抑制;凋亡抑制的MALT淋巴瘤病例中API2 mRNA及蛋白水平明显高于没有明显凋亡抑制的病例,但Caspase3 mRNA及蛋白水平在两组病例中表达没有明显的差异。结论:MALT淋巴瘤中存在明显的凋亡抑制,其发生与凋亡抑制因子API2的表达上调有关,但API2对凋亡的调节与Caspase3有关的信号传导通路无明显相关。  相似文献   
82.
高密度cDNA微阵列技术检测乳腺癌差异表达基因   总被引:1,自引:1,他引:0  
目的 描绘乳腺癌的基因差异表达谱,以寻找乳腺癌新的肿瘤相关候选基因和分子标志。方法 用含14000个cDNA克隆的表达微阵列检测乳腺癌组织、乳腺癌旁组织及乳腺非癌组织的mRNA表达,并分析其表达的差异。结果 乳腺癌组织与乳腺非癌组织比较有80个差异表达基因,乳腺癌组织与乳腺癌旁组织比较有57个差异表达基因,乳腺癌旁组织与乳腺非癌组织比较有29个差异表达基因,在乳腺癌组织与乳腺非癌组织和乳腺癌旁组织比较中有14个差异表达基因是一致的。结论 用微阵列技术对乳腺癌的肿瘤相关基因和分子标志作初步探索,为了解中国女性乳腺癌发生发展的分子机制、发展新的诊断和治疗手段提供了信息。  相似文献   
83.
To investigate procreation in schizophrenia, as well as gender-related differences, female patients with schizophrenia (n= 79, DSM-III-R criteria) were compared with screened female controls (n= 124) and subsequently with male patients (n=86). Two outcomes were investigated: (i) the proportion of subjects with one or more children (an index of fertility) and (ii) the number of children per subject among those with one or more children (an index of fecundity). Multivariate analysis was used to control for confounding variables. No significant differences in fertility between female patients and controls were detected, but reduced fecundity was noted among female patients past the reproductive period. Male patients showed a significant reduction in both fertility and fecundity compared to female patients. These results suggest that there is a relatively small impairment of fecundity among female patients compared with controls, but that there are more significant gender-related differences in both fertility and fecundity. The latter have important implications for the genetics of schizophrenia.  相似文献   
84.
A follow-up investigation of 24 patients with hereditary spasticity in a geographically isolated northern Swedish population, first examined by Böök (1953), was performed. Fifteen of them were dead. During the period from 1950–1972 five new cases of spastic syndromes were diagnosed in this population. The patterns of clinical symptoms and the genetic associations between the new and 24 previously reported patients with spastic syndromes were analyzed. Three of the five new cases had a specific syndrome. This starts in the first years of life with ataxia, which is followed by dysarthria, spasticity and jerky intention tremor. Initially the patients are mentally normal, but there seems to be slight mental deterioration through the years. The disorder is a progressive spinocerebellar degeneration with autosomal recessive inheritance.  相似文献   
85.
There are few reports of positron emission tomography (PET) in juvenile parkinsonism (JP). We report on the results of (18)F-6-fluoro-L-dopa (FD) PET in a 14-year-old patient with JP of 5 years duration associated with atypical features. This is the youngest subject to be investigated to date. There was a severe asymmetric reduction in striatal FD uptake, with a rostrocaudal gradient in the putamen similar to that seen in adult-onset idiopathic parkinsonism. Extensive DNA analysis in this patient did not show mutations in the parkin gene.  相似文献   
86.
目的:建立一种快速鉴定临床常见真菌菌种的方法。方法:选取真菌核糖体RNA的ITS区为靶基因,设计通用引物和种特异性探针,将3个属的6种临床常见真菌(白色念珠茵、热带念珠茵、光滑念珠茵、新型隐球菌、烟曲霉和黄曲霉)的种特异性探针加尾后固定于硝酸纤维素膜上;用标记生物素的真菌通用引物扩增11种医学真菌DNA,产物与固定在膜上的探针杂交。结果:通用引物可以扩增所试11种医学重要真菌的DNA,扩增片段长度约为560bp。6种真菌扩增产物只与其对应的探针杂交。结论:此方法快速、简便、特异,适合常规实验室开展。  相似文献   
87.
Molecular staging of head and neck squamous carcinoma   总被引:3,自引:0,他引:3  
The staging system of head and neck cancer is a Tumor-Node-Metastases system that was developed by the American Joint Committee on Cancer. The stage of the head and neck cancer defines the extent of the lesion and is determined by physical examination, radiologic studies, and pathologic examination. Accurate staging of head and neck cancer is critical since it will determine the treatment modalities used to cure the disease. Recent advances in the field of molecular genetics have allowed clinicians to detect occult cancer cells previously missed by physical examination and standard histopathologic techniques. Molecular assays are 500 times more sensitive in identifying cancer cells than standard techniques and provide more objective analyses with fewer sampling errors. Consequently, these techniques are currently being used to perform molecular staging of head and neck cancer patients. Preliminary results show that molecular staging will accurately identify those patients at significantly increased risk for recurrence of their head and neck cancer.  相似文献   
88.
A new and easily accessible concordance of nucleotide substitutions in the hypervariable segments of the human mitochondrial DNA (mtDNA) control region has been constructed. The concordance indexes all population-specific mtDNA sequences in a standardized format. The first edition of the concordance includes 1,440 sequences representing 762 mtDNA types from over 65 populations for hypervariable region 1, and 520 sequences representing 260 mtDNA types from over 26 populations for hypervariable region 2. Investigators are invited to submit new sequences to the database, and details for doing so are given in the text.  相似文献   
89.
Linkage disequilibrium (LD) analysis provides a powerful means for screening the genome to map the location of disease genes, such as those for bipolar disorder (BP). As described in this paper, the population of the Central Valley of Costa Rica, which is descended from a small number of founders, should be suitable for LD mapping; this assertion is supported by reconstruction of extended haplotypes shared by distantly related individuals in this population suffering low-frequency hearing loss (LFHL1), which has previously been mapped by linkage analysis. A sampling strategy is described for applying LD methods to map genes for BP, and clinical and demographic characteristics of an initially collected sample are discussed. This sample will provide a complement to a previously collected set of Costa Rican BP families which is under investigation using standard linkage analysis. © 1996 Wiley-Liss, Inc.  相似文献   
90.
Data from 2,903 adult same-sex twin pairs were analysed to investigate whether the genetic determinants of symptoms of panic are different from those underlying the neuroticism personality trait. Our results suggest that much of the genetic variation influencing the physical symptoms associated with panic is of the nonadditive type, perhaps due to dominance or epistasis. In both sexes these nonadditive genetic effects on physical symptoms influence the reporting of "feelings of panic". In males they also account for as much as half the genetic variance in neuroticism. The remainder is additive and also accounts for the balance of genetic variation in "feelings of panic". In females genetic variance in neuroticism is entirely additive but is not an important source of covariation with either panic symptom. Thus, symptoms of panic seem to be shaped in part by unique genetic influences which do not affect other anxiety symptoms. That a substantial part of the genetic variance in neuroticism in males may be due to the nonadditive effects on physical symptoms of panic may help to explain the rather low correlation between the genetic influences found to affect neuroticism in males and their counterparts in females.  相似文献   
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