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41.
We present here a large Israeli-Arab kindred with hereditary deafness. In this family 55 deaf subjects (29M, 26F), who are otherwise healthy, have been identified and traced back five generations to one common female ancestor. The deafness is progressive in nature, usually presenting in infancy and childhood. Audiometry on six deaf and seven unaffected subjects was consistent with severe to profound sensorineural hearing loss. Based on formal family segregation analysis, the inheritance of deafness in this family closely fits the expectation of a two locus model owing to the simultaneous mutation of a mitochondrial gene and an autosomal recessive gene. Thus, this disorder appears to have the unusual features of being an inherited tissue specific mitochondrial disease and apparently requiring the homozygous presence of a nuclear gene for clinical expression. Most importantly, this disorder presents a unique opportunity to investigate the molecular basis of hereditary non-syndromic deafness and normal hearing.  相似文献   
42.
患者男,5 5岁。因“发现右上腹包块5年,疼痛30d”于2 0 0 2年12月2 4日入院。查体:腹平软,右肋下约10cm处可扪及一包块,无压痛及反跳痛,肝肾区无叩痛,肠鸣音正常。于2 0 0 2年12月30日行右侧腹壁肿瘤切除术,术中见右侧腹壁有一约15cm×10cm×12cm大小灰红色肿物,累及腹膜浅层及肌层,部分区域与大网膜粘连,肿瘤未侵及皮下,压迫右肝前叶,余腹内脏器无异常。肿瘤质硬,边界尚清楚,肿物切面质脆,呈鱼肉状,中央部分坏死。病理检查:灰白灰红色组织1个,大小为15cm×10cm×8cm ,表面有一层纤维包膜,切面淡黄色,鱼肉状,部分区域呈黏液样,可见一8cm×6c…  相似文献   
43.
诱导供者特异性免疫耐受是最终克服移植排斥提高受者生存质量的有效途径之一。近年随着对树突状细胞发育成熟过程的认识步步深入,树突状细胞在移植排斥和移植耐受平衡中的双向调节作用引入注目。  相似文献   
44.
A highly efficient direct injection/on-line guard cartridge extraction-tandem mass spectrometry (DI/GCE-MS-MS) method has been validated for high-throughput evaluation of cytochrome P450 (CYP) 2D6 inhibition potential using human hepatic microsomes and 96-well microtiter plates. Microsomal incubations were terminated with formic acid, centrifuged, and the resulting supernatants were injected for DI/GCE-MS-MS analysis. Due to the novel use of an extremely short C18 guard cartridge, this method exhibits several advantages, such as no sample preparation, excellent on-line extraction, short run time (2.5 min), and minimized source contamination and performance deterioration. The DI/GCE-MS-MS method demonstrates acceptable accuracy and precision for the quantification of dextrorphan, a marker metabolite of dextromethorphan mediated by CYP2D6, in microsomal incubations. The CYP2D6 inhibition assay has been validated using quinidine as a known selective inhibitor of the isoform. The IC50 value (0.20 microM) measured by the new method is in good agreement with the literature value (0.22 microM).  相似文献   
45.
46.
The early outward current in opener muscle fibres of crayfish (Procambarus clarkii) was studied using the two-electrode voltage-clamp technique. This current was abolished in Ca2+-free and 5 mM Cd2+ solutions, and was blocked by extra- or intracellular tetraethylammonium, indicating that it was a Ca2+-dependent K+ current [I K(Ca)]. I K(Ca) was voltage dependent, apamin insensitive and sensitive to charybdotoxin (CTX), which, in addition to its tetraethylammonium sensitivity, suggests that the channels mediating I K(Ca) behave in a BK type manner. I K(Ca) activation was extremely fast, reaching a maximum within 5 ms, and the inactivation was incomplete, stabilizing at a persistent steady-state. I K(Ca) was insensitive to intracellular ethylenebis(oxonitrilo)tetraacetate (EGTA), but was abolished by injection of the faster Ca2+ chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N,N'-tetraacetic acid (BAPTA), suggesting that voltage-dependent Ca2+ channels and those mediating I K(Ca) should be clustered closely on the membrane. Under two-electrode current-clamp recording mode, low amplitude, graded responses were evoked under control conditions, whereas repetitive all-or-none spikes were elicited by application of CTX or after loading the cells with BAPTA. We conclude that I K(Ca) activates extremely quickly, is persistent and is responsible for the generation and control of the low amplitude, graded, active responses of opener muscle fibres.  相似文献   
47.
软组织平滑肌肉瘤中p16基因的甲基化检测   总被引:2,自引:2,他引:2  
Xu J  Yang G  Bu H  Guo L  Zhang S  Liu J 《中华病理学杂志》2001,30(1):16-18
目的 探讨软组织平滑肌肉瘤(LMS)中p16基因INK4A的甲基化状态及其与p16表达的关系。方法 应用MSP法检测38例软组织平滑肌肉瘤,10例平滑肌瘤及5例正常平滑肌组织中p16基因INK4A的甲基化状态,用免疫组织化学SP方法检测p16蛋白表达情况。结果 38例LMS中9例发生异常甲基化,异常甲基化率为23.7%(9/38)。其中,7例p16蛋白表达阴性,2例p16蛋白弱阳性,在p16蛋白表达阴性的LMS中,异常甲基化率为50%(7/14)。结论 p16基因第一外显子启动子区5‘CpG岛的异常甲基化是导致p16基因失活、蛋白缺如的重要基因外机制,并可能参与肿瘤的发生。  相似文献   
48.
Metaplastic carcinomas of the breast are uncommon breast tumors with aberrant cellular differentiation, most commonly showing ductal, squamous, and mesenchymal components. A breast carcinoma composed of both epithelial and melanocytic differentiation is rare, with only four previously reported cases in the literature. We present the fifth reported case, where the diagnosis was suggested by fine-needle aspiration (FNA) and later confirmed after the surgical specimen was excised. Histologically, this neoplasm revealed multidirectional differentiation, consisting primarily of squamous and melanocytic cell types, with focal glandular and osseous metaplasia. Based on the morphologic, immunohistochemical, and ultrastructural findings, we conclude that such tumors fall within the spectrum of metaplastic carcinomas of the breast. We believe that this case will further contribute to the understanding of this enigmatic tumor.  相似文献   
49.
To evaluate enzyme immunoassay (EIA) as an alternative to indirect immunofluorescence assay (IFA) to screen for Q fever in humans, 157 serum samples from patients suspected of having the disease were tested for immunoglobulin G antibodies toCoxiella burnetii. The agreement between the tests and the sensitivity of EIA were excellent (96.8% and 98.4%, respectively) when an IFAtiter of > 1/160 was considered positive. All serum samples with a titer of > 1/320 in the IFA were also positive by the EIA. The EIA seems to be an acceptable alternative to IFA for screening for Q fever.  相似文献   
50.
Bundesgesundheitsblatt - Gesundheitsforschung - Gesundheitsschutz - Wissenschaftliche Ergebnisse können eine Wissensquelle für kommunale Akteurinnen und Akteure der...  相似文献   
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