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1.
板蓝根抑菌抗炎活性部位的评价   总被引:27,自引:0,他引:27  
目的:评价和比较板蓝根5个化学部位抑菌、抗炎活性的强弱。方法:采用管碟法测定板蓝根不同化学部位对于金黄色葡萄球菌、铜绿假单胞菌的敏感性,观察对二甲苯所致小鼠耳廓肿胀的抑制作用。结果:板蓝根Ⅴ部位体外抑菌活性最强,Ⅴ部位具有显著的抗炎活性。结论:板蓝根中高极性成分具有很强的药理活性,是其发挥清热解毒功效的物质基础。  相似文献   
2.
目的 :观察硒和 或维生素E对高脂饲料所致实验性高脂血症大鼠心、肝、肾及血清脂质过氧化和一氧化氮含量的影响 ,探讨硒和维生素E抗脂质过氧化的作用。方法 :采用高脂饲料致大鼠实验性高脂血症 ,然后分组给予经预试后的硒和 或维生素E ,4wk后行乙醚麻醉取血 ,同时取心、肝、肾组织作匀浆 ,采用硫代巴比妥 (TBA)法测各组织或血清丙二醛 (MDA)含量以反映脂质过氧化水平 ;采用硝酸还原酶法测定上述组织的一氧化氮 (NO)含量。结果 :高脂饲料可致实验性大鼠高脂血症 ,与对照组比较 ,甘油三脂 (TG)、极低密度脂蛋白胆固醇 (VLDL C)升高 (P <0 .0 5) ;总胆固醇 (T CHOL)、低密度脂蛋白胆固醇 (LDL C)升高 (P <0 .0 1 )。高脂饲料可致部分组织或血清的脂质过氧化作用加强 ,增加各实验组织MDA含量 ,其中肝脏和血清MDA较对照组高(P <0 .0 5)。高脂饲料可致心肌及肝脏组织NO含量降低但却升高血清及肾脏组织NO含量。单独使用硒或维生素E或二者合用可不同程度降低高脂饲料所致的MDA含量升高 (P <0 .0 5或P <0 .0 1 ) ,也能不同程度地增加心、肝、肾及血清的NO含量 (P <0 .0 5或P <0 .0 1 ) ,合用比单独使用作用更明显。结论 :硒和维生素E单独或联合应用可降低高脂血症大鼠血脂升高所致的脂质过氧化增强作用 ,并能增加  相似文献   
3.
The optimized geometries, interaction energies, dipole moments, and vibrational frequencies of guanine-hydrogen peroxide (GHP), cytosine-hydrogen peroxide (CHP), adenine-hydrogen peroxide (AHP), thymine-hydrogen peroxide (THP), guanine–cytosine-hydrogen peroxide (GC-(HP)n(= 1–2)), and adenine–thymine-hydrogen peroxide (AT-(HP)n(= 1–2)) complexes are investigated by ab initio methods and ABEEMσπ/MM fluctuating charge potential model. All geometries of guanine–cytosine-hydrogen peroxide (G–C-HP) and adenine–thymine-hydrogen peroxide (A–T-HP) complexes were obtained using B3LYP/6-311++G(d,p) method, and the energies were determined at the MP2/6-311++G(2d,2p) level with BSSE corrections. The ABEEMσπ/MM model gives reasonable geometries and interaction energies compared with the present ab initio methods. For G–C-HP and A–T-HP clusters, the linear coefficient of the interaction energies all reaches 0.998, and the average absolute deviation (AAD) are 0.95 and 1.42 kcal/mol, respectively, when compared with MP2/6-311++G(2d,2p)‖B3LYP/6-311++G(d,p) method. Moreover, the variations of hydrogen bond length of guanine–cytosine and adenine–thymine base pair affected by hydrogen peroxide molecules computed by ABEEMσπ/MM model are all obtained reasonable accordance with B3LYP results. The current study will avail to understanding the physiological relevance in DNA damage.  相似文献   
4.
目的:应用快速蛋白液相色谱(FPLC)系统从肝癌组织中分离和纯4EHSP70-肽复合物,并研究其对肝癌细胞系HepG-2增殖的影响.方法:将组织进行匀浆、高速离心提取总蛋白后依次进行ConA-Sepharose亲和层析和 DEAE-Sephacel子交换层析分离纯化,所得蛋白经SDS-聚丙烯酰胺凝胶电泳和Western blot进行蛋白分子质量及性质鉴定,Bradford 法测定蛋白浓度;利用MTT方法检测HSP70- 肽复合物对HepG-2细胞增长的情况.结果:分离、纯化得到的蛋白经SDS-聚丙烯酰胺凝胶电泳、考马斯量蓝鉴定为单一带, 分子质量为70 kDa;Western blot结果证实为 HSP70,每10 g组织最终获得1.5 mg的HSP70; HSP70刺激组12,48,72 h与对照组的A值之间有显著差异(0.1 mg/L:t=-0.2500,P=0.00; t=-0.1777,P=0.001:t=-0.3094,P=0.001; 0.5 mg/L:t=-0.2878,P=0.00;t=-0.2044,P= 0.00;t=-0.3285,P=0.00;1 mg/L:t=-0.3118, P=0.00;t=-0.2592,P=0.00;t=-0.1994, P=0.025;5 mg/L:t=-0.4007,P=0.00;t= -0.1302,P=0.016;t=-0.2537,P=0.005),细胞存活率明显高于对照组(P<0.01).结论:使用本分离纯化方法可获得高纯度 HSP70肽复合物;HSP70肽复合物可以促进 HepG-2细胞的生长.  相似文献   
5.
AIM: Human beta-defensin (HBD)-1 and HBD-2 are endogenous antimicrobial peptides. Unlike HBD-1, the HBD-2 expression is augmented by Helicobacter pylori (H pylori). We sought to determine HBD-1 and HBD-2 concentrations in gastric juice during H pylori infection. METHODS: HBD-1 and HBD-2 concentrations were measured by radioimmunoassay in plasma and gastric juice of 49 H pylori-infected and 33 uninfected subjects and before and after anti-H pylori treatment in 13 patients with H pylori-associated gastritis. Interleukin (IL)-1beta and IL-8 concentrations in gastric juice were measured by enzyme-linked immunosorbent assay (ELISA). Histological grades of gastritis were determined using two biopsy specimens taken from the antrum and corpus. Reverse phase high performance liquid chromatography (RP-HPLC) was used to identify HBD-2. RESULTS: HBD-2 concentrations in gastric juice, but not in plasma, were significantly higher in H pylori-positive than -negative subjects, albeit the post-treatment levels were unchanged. Immunoreactivity for HBD-2 was exclusively identified in H pylori-infected mucosa by RP-HPLC. HBD-2 concentrations in gastric juice correlated with histological degree of neutrophil and mononuclear cell infiltration in the corpus. IL-1beta levels correlated with those of IL-8, but not HBD-2. Plasma and gastric juice HBD-1 concentrations were similar in H pylori-infected and uninfected subjects. CONCLUSION: Our results place the beta-defensins, especially HBD-2, in the front line of innate immune defence. Moreover, HBD-2 may be involved in the pathogenesis of H pylori-associated gastritis, possibly through its function as immune and inflammatory mediator.  相似文献   
6.
AIM: There is strong evidence that tyrosine kinases are involved in the regulation of tumor progression, cellular growth and differentiation. Recently, many kinds of tyrosine kinase receptors have been reported, among them Tie-1 and Tie-2 receptors constitute a major class. Angiopoietin (Ang)-1 is known as a ligand of Tie-2 tyrosine kinase receptor. The objective of this study was to establish a comprehensive Tie-1 and Tie-2 and Ang-1, 2 and 4 expression profile in human colorectal adenocarcinomas. METHODS: We examined 96 cases of surgically resected human colorectal adenocarcinoma by immunohistochemistry and investigated the statistical correlation between the expressions of Ties and Angs and clinicopathological factors. RESULTS: Among the 96 cases of adenocarcinoma, 87 (90.6%), 92 (95.8%), 83 (86.5%), 89 (92.7%), and 76 cases (79.2%) showed positive staining in the cytoplasm of carcinoma cells for the Tie-1 and Tie-2 and Ang-1, 2 and 4 proteins, respectively. Histologically, the expressions of Ties and Angs were variable. The expressions of Ties and Angs were correlated with several clinicopathological factors, but did not correlate with the presence of lymph node metastasis. Ties and Angs were highly expressed in human colorectal adenocarcinoma cells. CONCLUSION: These findings suggest that the Tie-Ang receptor-ligand complex is one of the factors involved in the cellular differentiation and progression of human colorectal adenocarcinoma.  相似文献   
7.
湖北省人群寄生虫感染情况的调查   总被引:1,自引:0,他引:1  
按全国人体寄生虫分布调查实施细则的要求和方法对咸宁、汉川、红安和安陆4县(市)14个点7125人作人体寄生虫感染情况的调查,另外,对3641名学龄前儿童作蛲虫感染情况的调查;随机检查农村妇女阴道毛滴虫1232人;对安陆市769名城关居民作人体蠕形螨感染情况调查。共检出寄生虫19种。其中蛔虫、钩虫、鞭虫、蛲虫、姜片虫、华支睾吸虫、并殖吸虫、棘口科吸虫、东方毛圆线虫、带绦虫、微小膜壳绦虫、溶组织内阿米巴、结肠内阿米巴、贾第虫、布氏嗜碘阿米巴、微小内蜒阿米巴、人毛滴虫、阴道毛滴虫和人蠕形螨的感染率依次为27%、2%、20.3%、7.1%、1.7%、0.3%、0.1%、0.2%、0.06%、0.2%、0.03%、0.2%、2.3%、0.2%、0.02%、0.2%、0.04%、7.3%和22.8%。所查见的虫种除蛔虫、鞭虫和阿米巴原虫等较常见的虫种外,还查见了棘口科吸虫、微小膜壳绦虫、毛圆线虫和贾第虫等较少见的虫种。在地理分布上,以山区和湖区为主的咸宁市和汉川县查见的虫种较多,而以平原丘陵为主的安陆市和红安县查到虫种较少。  相似文献   
8.
Nutcracker syndrome (NCS) is a rare pathology manifested by pain or hematuria in males and females alike. It can be easily overlooked, and should be considered in young men or women with symptoms of extended duration. We present a case of a 54-year-old female with chronic lower abdominal pain radiating to the left thigh of 4 years in duration. Computed tomography (CT) eventually revealed engorged left renal, gonadal, and uterine veins due to compression between the superior mesenteric artery (SMA) and the abdominal aorta, consistent with NCS. After a successful endovascular stenting and a 6-month period of antiplatelet and anticoagulant therapy, the patient returned to stable health. NCS, while rare, should be suspected in patients of both sexes with persistent pain or hematuria.  相似文献   
9.
Expression of β-catenin in hepatocellular carcinoma   总被引:6,自引:0,他引:6  
AIM: The β-catenin has been recognized as a critical member of the Wnt signaling pathway and plays an important role in the generation/differentiation of many tissues. Inappropriate activation of this pathway has been implicated in carcinogenesis. The mechanism underlying the development as well as its prognosis of hepatocellular carcinoma (HCC) has remained unclear. The purpose of this study is to analyze the expression of β-catenin in HCC in relation to histological grades and viral hepatitis backgrounds. METHODS: Thirty-two sections were selected at random from autopsy and surgical cases of HCC. Immuohistologically, the location and positivity of β-catenin expression in HCC was examined. RESULTS: Normal hepatocytes did not express β-catenin. In 78% of HCC β-catenin was expressed at the membrane of the cells, with or without cytoplasmic and/or nuclear expression. The tumor cells with well- and moderately-differentiated grades expressed frequently at the membrane and cytoplasm compared with poorly-differentiated type. Nuclear expression of β-catenin was prone to occur in the tumor cells of poorly-differentiated grade. There were 15% of hepatitis C virus (HCV) backgrounds with nuclear expression. In contrast, there was 38% with nuclear expression in hepatitis B virus (HBV) backgrounds. In nonBnonC hepatitis, no case expressed nuclear β-catenin. CONCLUSION: The β-catenin expression in HCC cells was heterogenous among types of hepatitis viral infection. Wnt signaling pathway might be deeply involved in less-differentiated HCC and HBV background.  相似文献   
10.
PURPOSE: Epigenetic alteration, via promoter hypermethylation, inactivates genes important for the development of head and neck squamous cell carcinoma (SCCHN). The aim of this study is to characterize and correlate, with clinical parameters, the promoter methylation profile of DNA repair genes, hMLH1 and O6-methylguanine-DNA methyltransferase (MGMT), and tumor-suppressor gene p16. MATERIALS AND METHODS: Fifty-one cases of SCCHN, collected from the paraffin block archives (1997-1999) in the Department of Pathology at the University of Arkansas for medical sciences, provided DNA for methylation-specific PCR using primers specific for hMLH1, MGMT, and p16. RESULTS: Sixty-two percent displayed promoter hypermethylation in at least one gene, with 23% seen for hMLH1, 30% for MGMT, and 36% for p16. Promoter hypermethylation of these genes separately or in combination was not associated with history of smoking and alcohol use, tumor size, nodal status, clinical stage, and overall survival. Promoter hypermethylation of more than 1 gene was significantly associated with increased 2-year disease-free survival. The probability of surviving 2 years without tumor recurrence was 100% with promoter hypermethylation in 2 or 3 genes and 46% with promoter hypermethylation in none or just 1 gene (P=.013). Promoter hypermethylation of 2 or 3 genes was independently related to increased 2-year cumulative disease-free survival (P=.028). CONCLUSIONS: Promoter hypermethylation of hMLH1, MGMT, and p16 genes was commonly detected in 47 SCCHN cases with up to 65% showing aberrant promoter hypermethylation in at least 1 gene. Promoter hypermethylation of 2 or 3 genes was significantly associated with increased 2-year disease-free survival, suggesting that promoter hypermethylation of multiple genes might improve survival. Significant correlation was also noted between a positive alcohol use history and promoter hypermethylation of the MGMT gene with no promoter hypermethylation of the p16 gene.  相似文献   
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