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31.
neurogenetics - Human RNF213, which encodes the protein mysterin, is a known susceptibility gene for moyamoya disease (MMD), a cerebrovascular condition with occlusive lesions and compensatory...  相似文献   
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A 20-year-old man with a germ cell tumor who experienced an ischemic stroke as a complication of cisplatin/etoposide/bleomycin based chemotherapy is reported. The previously reported cases are reviewed as well as the different physiopathologic mechanisms associated with vascular toxicity of this regimen.  相似文献   
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Keratinocytes influence the number, morphology, and proliferation of melanocytes. An interference in the melanocyte-keratinocyte relationship may contribute to melanoma development. This study examined the expression of apoptotic and proliferative markers in keratinocytes in lentigo maligna to characterize the epidermis permissive to these lesions. Formalin-fixed and paraffin-embedded tissues from 25 samples of lentigo maligna, 20 samples of solar keratoses, and 5 samples each of normal sun-exposed and non-sun-exposed skin (controls) were immunostained with antibodies directed against the proapoptotic markers bax and p53, the antiapoptotic marker bcl-2, and the proliferation marker ki-67. Eight percent of the lentigo maligna samples were positive for keratinocyte expression of bcl-2, 24% were positive for p53, and 76% were positive for bax; respective findings for solar keratoses were 35%, 85%, and 90%. Comparison with normal sun-exposed skin yielded lower rates of keratinocyte proliferation in 56% of the lentigo maligna samples, similar rates in 36%, and higher rates in 8%; for solar keratoses, proliferation was higher than controls in 60% of samples, similar in 35%, and lower in 5%. All these differences were statistically significant. These findings indicate that there are variable patterns of epidermal reaction to chronic sun exposure. The epidermis in lentigo maligna shows overall low proliferation and an apparently low apoptotic tendency. The dysfunctional epidermis may be permissive to aberrant melanocyte proliferation in the early stages of melanoma development.  相似文献   
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Regeneration of periodontal and alveolar ridge defects utilizing membranes is a well-established procedure in reconstructive surgery. Biomaterial characteristics and membrane design employed in guided tissue regeneration (GTR) techniques play an important role in good results. The purpose of this histologic experimental study in rats was to compare the use of two physical barriers in the osteopromotion by using GTR principles in bone defects created in tibias. Fifteen animals divided into 3 groups were used: group I (non-porous polytetrafluoroethylene (PTFE) barrier), group II (coral hydroxyapatite (HA) blocks), and group III (defects that received no physical barrier). Histological examination showed varied amounts of newly formed bone beneath both types of barriers. The non-porous PTFE barrier showed better results than the HA group. The results of this study suggest that bone regeneration can be successfully enhanced by a submerged membrane technique.  相似文献   
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MUG─Indole快速检定大肠杆菌方法研究   总被引:1,自引:0,他引:1  
本文报道用MUG-Indole检定大肠杆菌方法,在24h内能将94%~97%的大肠杆菌检出。对MUG阳性、Indole阴性或MUG阴性、Indole阳性的菌株,辅以EMB琼脂或麦康凯琼脂平板分离,挑选可疑菌落,做IMViC试验,使假阳性和假阴性降到最低水平。本法比传统的生化试验检定大肠杆菌法快速、简便、准确、无主观性。  相似文献   
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The pathogen Brucella abortus resides inside macrophages within a unique, replication-permissive organelle that is derived from the endoplasmic reticulum (ER). Although dependent on the Brucella type IV secretion system VirB, the mechanisms governing the biogenesis of this compartment remain elusive. Here, we investigated a putative role of the early secretory pathway in ER membrane accretion by the Brucella-containing vacuoles (BCVs). We show that BCVs interact with ER exit sites (ERES), and blockade of Sar1 activity, which disrupts ERES, prevents intracellular replication of Brucella. In cells expressing the dominant interfering form Sar1[T39N], BCVs do not acquire ER membranes, suggesting that they are unable to mature into replicative organelles. By contrast, treatments that block subsequent secretory events do not affect bacterial replication. We propose that Sar1-dependent ERES functions, but not subsequent secretory events, are essential for the biogenesis of the Brucella replicative compartment and, thus, bacterial replication. These results assign an essential role for Sar1 in pathogenesis of an intracellular bacterium.  相似文献   
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