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991.
氧化苦参碱对人结肠癌细胞P21,P27,Cyclin E1及CDK2表达的影响   总被引:2,自引:0,他引:2  
目的:观察氧化苦参碱(OM)对人结肠癌细胞P21,P27,Cyclin E1及CDK2表达的影响,研究其抑制细胞增殖的其他途径,探讨OM抗肿瘤的作用机制.方法:培养人结肠癌细胞株SW1116,以2,3,4 g/L OM作用24和48 h,以流式细胞仪测定OM对SW1116细胞的周期阻断作用;并采用RT- PCR、Western blot法测定细胞周期相关蛋白P21、P27、Cyclin E1和CDK2的表达水平.结果:与对照组相比,不同浓度(2,3,4 g/L)OM可使细胞阻滞于G_1/G_0期(24 h:67.5%±0.1%,69.5%±1.4%,71.0%±1.0% vs 58.6%±0.4%,P<0.05;48h:68.5%±0.3%,71.9%±0.9%,78.0%±0.4% vs 58.8%±0.1%,P<0.05),下调Cyclin E1的mRNA和蛋白表达水平(P<0.05),上调细胞周期负调控因子P21、P27的mRNA及蛋白表达水平(P<0.05),降低CDK2的mRNA水平而对其蛋白表达无影响.结论:OM可能通过阻滞细胞周期,降低Cyclin E1蛋白,上调P21、P27的基因表达,来发挥其抗肿瘤作用.  相似文献   
992.
Background and Aim: The purpose of the present study was to investigate the influence of viral load on disease severity and analyze the possible relationship of the load of hepatitis A virus (HAV) with disease severity and laboratory findings. Methods: Fifty‐eight patients diagnosed with acute hepatitis A were used in the current study, of whom 12 patients progressed to severe acute hepatitis (s‐AH) defined on the basis of a prothrombin time (PT) of <40% and 46 patients were diagnosed as having mild acute hepatitis (m‐AH). The load of HAV was measured with real‐time polymerase chain reaction. Results: Peak viral load showed a significant correlation with alanine aminotransferase (ALT) (r = 0.363, P = 0.0048) and PT levels (r = ?0.330, P = 0.0110). In terms of disease severity, there was a significant correlation with ALT (r = 0.462, P = 0.0012) and PT levels (r = 0.400, P = 0.0059) in the m‐AH group, but not in the s‐AH group. A significant positive correlation of peak viral load with the C‐reactive protein level (r = 0.270, P = 0.0400) and a significant negative correlation of peak viral load with the platelet count (r = ?0.313, P = 0.0015) was also found. Conclusions: The load of HAV was closely correlated with liver damage and disease severity in m‐AH, but not in s‐AH. The load of HAV was also closely associated with the increase in C‐reactive protein level and enhancement of thrombocytopenia.  相似文献   
993.
用PCR诊断不同虫荷量的大鼠卡氏肺孢子虫肺炎的价值   总被引:1,自引:0,他引:1  
目的 评价在不同虫荷量条件下用 PCR诊断大鼠卡氏肺孢子虫肺炎 (PCP)的价值。 方法 将 PCP大鼠随机分为药物治疗组及未治疗组 ,测定其肺虫荷量 ,收集其支气管灌洗液 (BAL F)和血清标本 ,用 PCR和半套式 (Sn) PCR检测标本中的卡氏肺孢子虫基因 ,比较 PCR和环六亚甲基四胺银 (GMS)染色结果 ,及与病鼠肺虫荷量的关系。 结果 虫荷量高的未治疗组病鼠的 BAL F标本 PCR、Sn PCR及 GMS染色阳性率分别为 10 0 %、10 0 %和 92 .6 % ,差异无显著性 (P>0 .0 5 ) ;而虫荷量低的治疗组的 PCR(88.1% )、Sn PCR(94 .9% )阳性率均显著高于 GMS染色镜检阳性率 (30 .5 % ) (P<0 .0 5 )。肺虫荷量 >5 0 0个 /mg肺的 PCP大鼠 ,血清 PCR阳性率显著高于≤ 5 0 0者 (分别为 4 2 .9%和 1.7% )。 结论 PCR可用于虫株负荷量较低时的 PCP诊断 ,对判断 PCP病情及疗效考核亦有一定的帮助。  相似文献   
994.
BACKGROUND: Studies have shown that cystic fibrosis (CF) patients who are chronically infected with Burkholderia cepacia complex bacteria may potentially acquire new strains of B cepacia. Our objective was to determine whether pulmonary exacerbations of CF are associated with acquisition of new B cepacia strains or with B cepacia strain replacement. METHODS: Thirty-six patients from seven centers who were chronically infected with B cepacia complex bacteria were prospectively followed up over a 38-month period. Patients had sputum cultures performed every 3 months while clinically stable and at the time of a pulmonary exacerbation. Each B cepacia complex isolate was speciated by polymerase chain reaction amplification of the recA gene to determine species status and was genotyped by pulsed-field gel electrophoresis to determine strain type. RESULTS: Thirty-five of 36 patients (97%) had chronic infection with Burkholderia cenocepacia III-A during clinical stability. All 36 patients maintained the same species and strain of B cepacia complex at the time of exacerbation as was found during clinical stability. B cepacia complex isolates retrieved during exacerbations were significantly less susceptible to ciprofloxacin, chloramphenicol, piperacillin, meropenem, and tobramycin compared to isolates retrieved from the same patients during clinical stability. CONCLUSION: Adult CF patients infected with B cenocepacia maintain the same strain of B cenocepacia during exacerbations; pulmonary exacerbations are not caused by acquisition of a new B cepacia species or strain. B cepacia isolates retrieved during exacerbations may be more resistant to antibiotics.  相似文献   
995.
目的构建重组表达质粒pYES6-S,诱导SARS冠状病毒刺突蛋白(spikeprotein)在酿酒酵母中的表达并纯化。方法反转录获得SARS冠状病毒DNA片段,PCR法获得刺突蛋白基因互相重叠的四部分片段,酶切连接成全长,在大肠埃希菌E.coliJM109中构建重组表达克隆pYES6-S,在酿酒酵母巾诱导表达并纯化。结果重组克隆pYES6~S经酶切、测序鉴定确定,插入片段大小、方向、碱基匹配与预期一致,获得1个完整的刺突蛋白基因,表达产物纯化后,电泳鉴定,相对分子质量大小近110000。结论 成功克隆SARS冠状病毒刺突蛋白基因全长,并在酿酒酵母中诱导表达成功,有助于抗SARS分子疫苗的研究。  相似文献   
996.
In human African trypanosomiasis (HAT), two disease stages are defined: the first, or haemo‐lymphatic stage, and the second, or meningo‐encephalitic stage. Stage determination forms the basis of therapeutic decision and is of prime importance, as the drug used to cure second‐stage patients has considerable side‐effects. However, the tests currently used for stage determination have low sensitivity or specificity. Two new tests for stage determination in the cerebrospinal fluid (CSF) were evaluated on 73 patients diagnosed with HAT in Côte d'Ivoire. The polymerase chain reaction (PCR) detecting trypanosome DNA (PCR/CSF) is an indirect test for trypanosome detection whereas the latex agglutination test detecting immunoglobulin M (LATEX/IgM) is an indicator for neuro‐inflammation. Both tests were compared with classically used tests, double centrifugation and white blood cell count of the CSF. PCR/CSF appeared to be the most sensitive test (96%), and may be of use to improve stage determination. However, its value for therapeutic decision appears limited, as patients whose CSF was positive with PCR were successfully treated with pentamidine. This result confirms those of previous works that showed that some patients with trypanosomes in the CSF could be treated successfully with pentamidine. LATEX/IgM, which depending on the cut‐off, showed lower sensitivity of 76% and 88%, but higher specificity of 83% and 71% for LATEX/IgM 16 and LATEX/IgM 8 respectively, appears more appropriate for therapeutic decision making.  相似文献   
997.
Summary HLA DQ chain, in particular amino acid at position 57, has been reported to contribute to susceptibility and resistance to Type 1 (insulin-dependent) diabetes mellitus in Caucasians. Resistance has been proposed to be conferred by aspartic acid at this position. To ascertain the association of HLA DQ and DR genes with Type 1 diabetes in Japanese subjects, ten Japanese Type 1 diabetic patients were investigated at DNA level. Genomic DNA was amplified by polymerase chain reaction, and dot blot analysis was carried out using the amplified DNA with allele specific oligonucleotide probes. All patients had aspartic acid at position 57 of at least one of their two DQ chains, and there was no significant difference of amino acids at the same position of DR chain in patients compared to control subjects. These data indicate that the protective role of aspartic acid at position 57 of DQ chain is less significant in Japanese compared with Caucasian subjects.  相似文献   
998.
999.
在显微镜下用紫外激光微切机将单个胰岛从胰腺切片中切下,提取RNA后逆转录成cDNA并在实时定量RY—PCR中得到有效的扩增,其表达量与细胞数量成正比。  相似文献   
1000.
We describe a 36-year-old man with advanced multiple myeloma (Salmon and Durie stage III) who developed jaundice and severe cholestasis after a first cure with systemic chemotherapy of vincristine, doxorubicin, and oral dexamethasone (VAD). Serology for hepatitis A, B, and C and for CMV was negative. A liver ultrasound and CT scan showed mild hepatomegaly without evidence of extrahepatic or intrahepatic biliary tree dilatation. A percutaneous liver biopsy revealed perisinusoidal deposits of an abundant slightly eosinophilic, PAS-positive amorphous substance. Immunohistochemistry showed positivity for kappa-light chains and was negative for lambda-light chains, for IgA, IgG, IgM, and IgD immunoglobulins as well as for AA and AL proteins and for amyloid P component. A diagnosis of light chain deposition disease (LCDD) of the liver was made. The patient developed rapid deterioration of liver function, leading to a multisystem dysfunction and death. The occurrence of LCDD in multiple myeloma is close to 5% and myeloma is the underlying disease in two thirds of patients with LCDD. The kidneys are involved in almost all cases of LCDD and renal dysfunction usually reveals the disease. Only three patients with LCDD of the liver without overt renal involvement have been reported so far. This is the first observation of LCDD presenting with jaundice and severe cholestasis shortly after the diagnosis of high tumor mass myeloma, without overt renal involvement, leading rapidly to the patient's death.  相似文献   
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