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目的:对嗜麦芽窄食单胞菌临床分离株gzch770(SMgzch770)携带的喹诺酮耐药基因Smqnr进行扩增、测序及原核表达,为研究Smqnr蛋白的功能奠定基础。方法:提取SMgzch770基因组染色体,PCR扩增Smqnr全基因并克隆入pMD18-T载体进行核苷酸序列分析;将Smqnr基因克隆至表达载体pGEX-4T-1,转化大肠杆菌BL21,SDS-PAGE分析融合蛋白表达情况。结果:以染色体DNA为模板,成功扩增660bpSmqnr基因;序列比对分析显示其与相关报道序列核苷酸和氨基酸一致性达98%以上;SMgzch770Smqnr序列已登录GenBank(登录号:HQ315851);SDS-PAGE显示,融合基因表达的蛋白约为50kDa,其中Smqnr蛋白约为24kDa。结论:从SMgzch770中成功克隆及表达了Smqnr基因,为进一步进行Smqnr蛋白高级结构测定的结晶试验提供了必须材料。  相似文献   
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The goal of this study was to determine whether two stressors commonly used to model aspects of neuropsychiatric disease in rats have an additive effect on striatal dopamine type 2 receptor (D2R) expression, a key player in the etiology of neuropsychiatric disease.  相似文献   
998.
《Pancreatology》2014,14(6):497-502
Background/objectivesChronic pancreatitis (CP) is a disabling disease characterised by abdominal pain, and various pancreatic and extra-pancreatic complications. We investigated the interactions between pain characteristics (i.e. pain severity and its pattern in time), complications, and quality of life (QOL) in patients with CP.MethodsThis was a cross-sectional study of 106 patients with CP conducted at two North European tertiary medical centres. Detailed information on clinical patient characteristics was obtained from interviews and through review of the individual patient records. Pain severity scores and pain pattern time profiles were extracted from the modified brief pain inventory short form and correlated to QOL as assessed by the EORTC QLQ-C30 questionnaire. Interactions with exocrine and endocrine pancreatic insufficiency, as well as pancreatic and extra-pancreatic complications were analysed using regression models.ResultsPain was the most prominent symptom in our cohort and its severity was significantly correlated with EORTC global health status (r = −0.46; P < 0.001) and most functional and symptom subscales. In contrast the patterns of pain in time were not associated with any of the life quality subscales. When controlling for interactions from exocrine and endocrine pancreatic insufficiency no effect modifications were evident (P = 0.72 and P = 0.85 respectively), while the presence of pancreatic and extra-pancreatic complications was associated with an almost 15% decrease in life quality (P = 0.004).ConclusionsPain severity and disease related complications significantly reduce life quality in patients with CP. This information is important in order to design more accurate and clinical meaningful endpoints in future outcome trials.  相似文献   
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Although the histogenesis of sebaceous carcinomas remains unclear, the occurrence of intraepidermal or intraepithelial sebaceous carcinoma in the epidermis or conjunctiva may suggest de novo histogenesis. This report describes a case of sebaceous carcinoma within preexisting rippled/carcinoid pattern sebaceoma. This lesion was composed of two (benign and malignant) components, and the benign component of the lesion showed the typical features of a rippled/carcinoid pattern sebaceoma. Although evidence of trauma as well as a vertical orientation was seen in this lesion, the malignant component of the lesion showed histopathological evidence of malignancy (sebaceous carcinoma), such as the aggregations with irregular and infiltrated borders, a sheet‐like growth pattern, and the cytopathological findings of the neoplastic cells, showing a high‐grade of malignancy (a high mitotic index and abnormal mitotic figures). The immunohistochemical staining for p53, Ki‐67 and D2‐40 also favored this diagnosis. This sebaceous carcinoma component was considered to be the incipient stage of carcinoma within preexisting sebaceoma, therefore, it was still considered to be a vertically oriented lesion. This case shows the possibility that abnormal (malignant) sebaceous germinative cells may originate within a sebaceoma, thereby suggesting that some sebaceous carcinomas may develop from preexisting sebaceomas.  相似文献   
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