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901.
含编码人精子膜多肽cDNA和乙肝表面抗原基因的重组痘苗病毒 总被引:1,自引:2,他引:1
合成编码一种人精子膜蛋白YWK-Ⅱ胞外区的一段多肽片段的双链寡核苷酸链,HSD-2a.将HSD-2a和3’端乙肝表面抗原主S基因连接并与pUC18质粒重组.经鉴定的重组质粒用BamH Ⅰ和EcoRl酶切后,可分离纯化得到HSD-2a和HBsAg的主S基因连接片段,将该连接片段插入痘苗病毒通用表达载体pGJP-5的痘苗病毒启动子P_(7.5)下游,构建成重组质粒pGJP-HSD/HBs.将该重组质粒传染已感染了天坛痘苗病毒的猴肾细胞CV-1,pGJP-5中含有的TK基因与出发株病毒基因组的TK基因发生体内同源重组,构成重组痘苗病毒vv-HSD/HBs.HuTK~-细胞经vv-HSD/HBs感染后,在5-溴脱氧尿苷存在下进行空斑分析,筛选出TK~-重组病毒.应用ELISA方法对已感染了重组病毒的HuTK~-细胞培养上清和细胞裂解液测定,表明有HSD-2a编码的多肽片段的表达.Western-blot法分析呈现28和30Kd两条显色带.重组痘苗病毒vv-HSD/HBs有可能作为抗生育疫苗用途. 相似文献
902.
Beverly Barton Rogers John Sommerauer Albert Quan Charles F. Timmons D. Brian Dawson Richard H. Scheuermann Karen Krisher Carolyn Atkins 《Pediatric and developmental pathology》1998,1(6):480-486
To assess whether the semiquantitative peripheral blood Epstein-Barr virus (EBV) polymerase chain reaction (PCR) test correlates
with post-transplant lymphoproliferative disorder (LPD), we compiled the results of the test done over a 3-year period ending
July 1997. Six hundred seventy-six tests were done on 185 patients. Four hundred-thirty tests (63%) were negative, 167 (25%)
were weak positive, 67 (10%) were moderate positive, and 12 (2%) were strong positive. Twelve of the patients developed a
lymphoproliferative disorder (LPD) during this time. The EBV PCR tests proximate to the diagnosis of LPD in the 12 patients
with EBV-positive LPD were 6 strong positive, 5 moderate positive, 1 weak positive. No patient with LPD had a negative result
at diagnosis. Stated another way, 6/12 (50%) of strong-positive PCR tests, 5/67 (7%) moderate-positive tests, and 1/167 (.6%)
of weak-positive tests correlated with LPD. Serologic evaluation for EBV done on 7 patients at the time of LPD showed low
serologic responses in 5 of the 7 patients. The EBV PCR temporally associated with the serology indicated moderate to large
viral burdens. In each patient evaluated serially, the EBV PCR test rose before the diagnosis of LPD and fell with treatment
for the disorder. In conclusion, the EBV PCR test may be used as an adjunct to the diagnosis of patients with LPD and may
be used to monitor response to therapy for the disorder.
Received August 26, 1997; accepted January 13, 1998. 相似文献
903.
Differential patterns of circulating adhesion molecules in children with bronchial asthma and acute bronchiolitis 总被引:2,自引:0,他引:2
The object of the study was to assess the levels of circulating forms of the cellular adhesion molecules ICAM-I, VCAM-1, E-selectin, L-selectin and P-selectin in young children with asthma and acute bronchiolitis. Thirty-nine children aged 12 to 84 months with mild or moderate asthma were studied at admission for acute asthma (n = 15) or in a stable phase (n = 24). Ten of the children with acute asthma were seen again after one month. Twenty-two children aged 1 to 17 months with acute bronchiolitis and nine non-atopic controls were also included in the study. In children with acute asthma, the mean concentration of circulating soluble ICAM-1 (SICAM-I) was increased compared to children with stable asthma (mean 442 μg/l versus 363 μg/l; p < 0.001) and to controls (363 μg/l; p < 0.05). The levels of SICAM-1 remained high at follow up. In children with stable asthma, the mean serum concentration of soluble L-selectin (sL-selectin) (2080 μg/l) was significantly higher than in the controls (1664 μg/l; p < 0.05). The levels of circulating cellular adhesion molecules were similar in atopic and non-atopic asthmatics. Children with acute bronchiolitis had increased serum levels of soluble VCAM-1 (sVCAM-I) (1637 μg/l versus 1019 μg/l in the controls; p < 0.01) and sL-selectin (2041 μg/l versus 1664 μg/l in the controls; p < 0.05). There was no difference between the levels of circulating cellular adhesion molecules in children with respiratory syncytial virus (RSV) positive and RSV negative bronchiolitis. Soluble E-selectin (sE-se-lectin) and soluble P-selectin (sP-selectin) in serum were not significantly increased in any of the groups studied. In conclusion, our data suggest differential patterns of circulating cellular adhesion molecules in young children with acute asthma, stable asthma, and acute bronchiolitis, which may reflect differences in the underlying inflammatory processes in these obstructive pulmonary diseases. 相似文献
904.
M. C. J. Kneyber A. H. Brandenburg R. de Groot K. F. M. Joosten P. H. Rothbarth A. Ott H. A. Moll 《European journal of pediatrics》1998,157(4):331-335
Respiratory syncytial virus (RSV) infections are characterized by upper or lower respiratory tract symptoms including bronchiolitis
and pneumonia. Apnoea may be the first sign of disease in children with RSV infection. The aims of this study were the identification
of independent risk factors for RSV associated apnoea and the prediction of the risk for mechanical ventilation in children
with RSV associated apnoea. Medical records of children younger than 12 months of age admitted with RSV infection between
1992 and 1995 to the Sophia Children's Hospital, were reviewed. Demographic parameters, clinical features and laboratory parameters
(SaO2, pCO2 and pH) were obtained upon admission and during hospitalization. Children with and without apnoea were compared using univariate
and multivariate logistic and linear regression analysis. One hundred and eighty-five patients with RSV infection were admitted
of whom 38 (21%) presented with apnoea. Patients with apnoea were significantly younger, had a significantly lower temperature,
higher pCO2 and lower pH and had on chest radiographs also more signs of atelectasis. The number of patients admitted to the ICU because
of mechanical ventilation and oxygen administration was significantly higher in children with RSV associated apnoea. Apnoea
at admission was a strong predictor for recurrent apnoea. The relative risk for mechanical ventilation increased with the
number of episodes of apnoea: 2.4 (95% CI 0.8 – 6.6) in children with one episode of apnoea (at admission) versus 6.5 (95%
CI 3.3 – 12.9) in children with recurrent episodes of apnoea.
Conclusions Age below 2 months is the strongest independent risk factor for RSV associated apnoea. Apnoea at admission increases the
risk for recurrent apnoea. The risk for mechanical ventilation significantly increases in children who suffer from recurrent
apnoea.
Received: 12 May 1997 / Accepted in revised form: 22 August 1997 相似文献
905.
To identify virological parameters (serostatus of hepatitis B surface antigen [HBsAg] and antibodies to hepatitis C virus [anti-HCV], HCV genotypes and HCV-RNA titer) and other clinico-biological and lifestyle variables that may influence or predict the development of hepatocellular carcinoma (HCC) in cirrhosis, we followed 100 cirrhotic patients without HCC, who visited Kyushu University Hospital between 1985 and 1987, until the end of 1995 (follow-up rate: 98%; average follow-up period: 5.3 years). After elimination of 4 patients who developed HCC or were censored within the initial 6 months, 37 (39%) out of 96 patients developed HCC during follow-up. As compared with HBsAg(+) patients, anti-HCV(+) HBsAg(–) patients demonstrated significantly elevated HCC risk (adjusted hazard ratio [HR]=5.85, 95% confidence interval [CI] 1.65–20.67). Genotype 1 HCV infection was not associated with increased risk compared with genotype 2 (HR = 0.64, 95% CI 0.21–1.99). For genotype 1 HCV infection, patients with HCV-RNA levels <1 Meq/ml tended to present lower risk than patients with ≥1 Meq/ml ( P = 0.03). Male sex, advanced Child's class, lower serum albumin, and higher serum aminotransferase and α-fetoprotein were also found to be strong predictors. Overall, drinking and smoking habits were not associated with significantly elevated risk. Among virological parameters, anti-HCV positivity and, possibly high HCV-RNA titer, were predictive of HCC occurrence in cirrhosis in our clinical setting. 相似文献
906.
原发性肝癌患者血清中庚型肝炎病毒基因的检测 总被引:2,自引:0,他引:2
用逆转录-聚合酶链反应法(PT-PCR)检测了67例原发性肝癌(PLC)患者血清中的庚型肝炎病毒(HGV)RNA,以PCR-双脱氧末端终止法分析了PCR产物的核苷酸序列。结果显示,HGVRNA的检出率为19.4%(13/67),其在HBsAg阳性组和HBsAg/抗HCV阴性组中的阳性率分别是12.2%(6/49)和50%(7/14);5’非编码区(5’-NCR)扩增片段的核苷酸序列与美国株GBV-C的同源性为91.7%,提示在我国PLC患者中存在HGV感染。 相似文献
907.
908.
Riccardo Dolcetti Paola Zancai Roberta Cariati Mauro Boiocchi 《Leukemia & lymphoma》1998,29(3):269-281
Retinoids have been shown to be effective in the chemoprevention and treatment of certain human malignancies. In this review, we will summarize our recent results concerning the effects of retinoids on the proliferation and differentiation of Epstein-Barr virus (EBV)-immortalized lymphoblastoid B-cell lines (LCLs), an in vitro model of EBV-related lymphoproliferative disorders arising in immunosuppressed hosts. Retinoids proved to be powerful inhibitors of the proliferation of EBV-infected LCLs in vitro, with 13-cis-retinoic acid (RA), all-trans-RA, and 9-cis-RA being the most effective compounds. Of note, retinoid-induced growth arrest in vitro appears irreversible at drug concentrations (10--6 mol/L) which may be reached in man after oral systemic therapy. The antiproliferative activity exerted by retinoids on LCLs is a generalized phenomenon usually associated with a progressive accumulation in G0/G1 phases of treated cells. The strong upregulation of p27Kipl invariably observed in cells exposed to retinoids may contribute to the decreased number of cycling cells, probably by inhibiting the transition from the G1 to S phase. Moreover, we obtained evidence indicating that the antiproliferative effects of retinoids are not dependent on the induction of terminal differentiation of EBV-immortalized B lymphocytes. In fact, the modifications induced by retinoids relative to LCL morphology, phenotype (downregulation of CD19, HLA-DR, and s-Ig, and upregulation of CD38 and c-Ig), and IgM production were highly variable among the lines tested and often only slightly relevant. Finally, the antiproliferative activity exerted by retinoids on LCLs is not mediated by a direct modulation of viral latent antigens, since EBNA-2 and LMP-1 downregulation was a late event detected only in some cell lines. These results indicate that retinoids may be useful in the medical treatment of EBV-related lymphoproliferative disorders of immunosuppressed patients, particularly in the earlier phases of these diseases. 相似文献
909.
F. L. Clark M. W. Drummond S. Chambers B. A. Chapman W. N. Patton 《Annals of oncology》1998,9(4):385-387
Chronic carriers of Hepatitis B virus (HBV) infection, who are treated for malignant lymphoma, are at high risk of mortality from reactivated HBV infection. We report a case of a 29-year-old male chronic HBV carrier who developed fulminant reactivated HBV infection following intensive chemotherapy for stage IVB large cell B-cell non-Hodgkin's lymphoma associated with extensive central nervous system and bone marrow involvement. Prior to chemotherapy the patient had normal liver function tests and was negative for HBV DNA by semi-quantitative PCR assay. Fulminant HBV reactivation was confirmed following clinical deterioration, massive rises in hepatic transaminases (peak alanine aminotransferase = 2,850 U/l), liver biopsy and rising levels of serum HBV DNA. Following treatment with lamivudine 150 mg bd for 18 weeks dramatic and sustained recovery ensued. Symptoms and liver function tests improved within days and HBV DNA became negative within 12 weeks. Our patient later died from relapsed lymphoma but without evidence of reactivated HBV infection. We advise that lamivudine should be considered during intensive chemotherapy treatment of chronic carriers of HBV. 相似文献
910.
EB病毒VCA-IgA抗体水平与鼻咽癌病人远期疗效关系 总被引:6,自引:1,他引:6
目的:分析EB病毒血清学VCA-IgA抗体与鼻咽癌病人远期疗效关系,为临床治疗提供参考依据。方法:1985年本院病理确诊的522例鼻咽癌病人,按治疗前、后VCA-IgA抗体滴度分为三组:低滴度组(1:5~1:20)、中滴度组(1:40~1:80)和高滴度组(1:160以上),随访10年,比较生存率的异同。结果:治疗前鼻咽癌病人高滴度组10年生存率低于低滴度组(P<0.05),但和中滴度组差别无显著性(P>0.05)。治疗后三组病人10年生存率比较,高、中滴度二组差别无显著性(P>0.05),但低于低滴度组。结论:EB病毒VCA-IgA抗体水平可以作为估计预后的重要参考依据,与远期疗效有密切关系。 相似文献