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125~I-后标记法是庄志雄等人(1994)提出的一种检测DNA-蛋白质交联物(DPCs)的新技术,该法在检测离体CHO细胞DPCs的实验中已显示出敏感、快速和简便的优点。本研究表明,125~I-后标记法不仅能有效地检出由紫外光和铬酸钾诱导的CHL细胞DPCs,并能有效而敏感地检测由铬酸钾和氯化镍引起的大鼠不同组织特别是白细胞DPCs形成的情况,是一种敏感的和可考虑应用于人群调查的DPCs检测方法。  相似文献   
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This study aimed to investigate whether endothelial cells are damaged and to evaluate fibrinolytic system function in patients with type 2 diabetes. For this proposal, plasma levels of von Willebrand factor (an endothelial marker of injury), homocysteine (an inductor of endothelial injury), D-dimer (a marker of coagulation cascade activation) and plasminogen activator inhibitor-1 (a fibrinolysis marker) were measured in individuals with both type 2 diabetes and high blood pressure, with type 2 diabetes, with high blood pressure and in healthy control individuals. No significant differences among groups were observed for von Willebrand factor and homocysteine plasma levels. The type 2 diabetes and high blood pressure group presented a significant difference to the other groups for D-dimer and also presented high values for plasminogen activator inhibitor-1. The high blood pressure group and type 2 diabetes group presented separately higher values of plasminogen activator inhibitor-1 compared with the control group. High levels of D-dimer and plasminogen activator inhibitor-1 in patients with type 2 diabetes and high blood pressure with normoalbuminuria therefore indicate a state of hypercoagulability and hypofibrinolysis, despite no evident microvascular injury supported by normal levels of von Willebrand factor and homocysteine.  相似文献   
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Ectodermal dysplasia with acanthosis nigricans (Lelis syndrome)   总被引:2,自引:0,他引:2  
A 31-year-old male patient with ectodermal dysplasia and acanthosis nigricans is described. Clinical findings included hypotrichosis, hypohidrosis, palmoplantar hyperkeratosis, nail dystrophy, early onset loss of permanent dentition, mental retardation, and acanthosis nigricans. The findings suggest the diagnosis of Lelis syndrome, as described on the basis of seven unrelated cases. A review concerning this condition is also presented.  相似文献   
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目的建立N一甲基一N’一硝基一N一亚硝基胍(N-methy1-N’-nitro-N-nitrosoguanidine,MNNG)诱发大鼠腺胃癌模型并观察p53,ras基因的表达。方法给Wistar大鼠饮用MNNG水溶液(终浓度为80μg/ml),用ABC法检测P53和P21蛋白的表达。结果MNNG成功地诱发出了胃癌、胃腺瘤、胃息肉、胃粘膜不典型增生和历上皮化生等病变。胃癌肝转移2例,淋巴结转移1例。P53蛋白在肠化及不典型增生皆阴性,胃癌阳性率为50%;P21蛋白在肠化及不典型增生中阳性率为44%,在癌组织中为23%。结论MNNG能诱发大鼠脾胃癌等病变,P53基因突变在胃癌发生发展过程中起一定作用,而ras基因激活是一个早期现象。  相似文献   
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Context The cervical teratomas are rare, benign tumors, they are formed by the three embryonic layers, and they represent only 6% of teratomas. The prognosis depends mainly on the size and location of the lesion, on the tumor growth rate, and on the level of tracheal compression. Prenatal diagnosis is usually reached with the aid of a two-dimensional ultrasonography (2DUS) after the 15th week of gestation, which shows a large heterogeneous mass in the cervical region, plus a polyhydramnios, on the Doppler mode which also shows the vascularization of the tumor. Case report We report a case of cervical teratoma diagnosed on the 31st week of gestation with the aid of a 2DUS and color Doppler mode. We focus on the main findings obtained with the three-dimensional ultrasonography in surface mode, and we highlight the importance of this methodology for the indirect evaluation of the neonatal prognosis.  相似文献   
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Diaphragm ultrasound (DUS) has been used to identify diaphragm dysfunction. However, its correlations with respiratory strength and lung function are unclear, even in healthy patients. A total of 64 healthy patients (30 males) had lung function and inspiratory strength (maximal inspiratory pressure and sniff nasal inspiratory pressure) measured. Gastric and oesophageal pressures were measured in a subgroup (n?=?40). DUS was characterized by mobility (quiet breathing [QB] and deep breathing [DB]) and thickness (at functional residual capacity [ThFRC] and total lung capacity [ThTLC]). We calculated the thickening fraction (TF). During QB, DUS was similar between sexes. However, during DB, females had lower mobility, thickness and TF than males. Mobility at DB, ThTLC and TF significantly correlated with lung function and inspiratory strength. These correlations were affected by sex. DUS correlated with inspiratory gastric pressure. In healthy patients, DUS correlated with lung function and inspiratory strength during DB. Significant differences between genders were noticeable when DUS was performed during DB.  相似文献   
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BACKGROUND: Oxidative stress plays a role in the pathogenesis of nonalcoholic steatohepatitis (NASH). Yo jyo hen shi ko (YHK) is a complex compound purported to reduce reactive oxygen species (ROS) by blocking the propagation of radical-induced reactions. The aim of this study was to evaluate the role of the effect of YHK in experimental NASH. METHODS: NASH was induced in male ob/ob mice by a high-fat (HF) diet or methionine/choline-deficient (MCD) diet for 4 weeks. YHK-treated animals received YHK solution orally (20 mg/kg/day) in both experimental diets (n=6; each group) while control animals received only vehicle. RESULTS: The MCD and HF groups developed moderate diffuse macrosteatosis, hepatocellular ballooning, and a diffuse inflammatory infiltrate. With the addition of YHK, there was a marked reduction in macrosteatosis in both groups. This was associated with decreased lipoperoxide and reduced glutathione-GSH concentrations as well as reduced serum aminotransferases and improved histological markers of inflammation. These changes were also associated with weight loss in the MCD+YHK group and diminished weight gain in the HF+YHK group. CONCLUSION: YHK therapy blunts the development of macrosteatosis in these models of NASH and significantly reduces markers of oxidative stress. YHK also diminishes weight gain in this obesity prone model. Our findings warrant further study on the mechanisms involved with these effects.  相似文献   
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