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1.
The aim of this study was to examine the predictors of long-term survival (>24 months) in patients with gall bladder cancer. A retrospective review of 117 cases of gall bladder cancer resected between 1989 and 2000. The resections included 80 simple cholecystectomies and 37 extended procedures. Patients with survival >24 months (n=44) were compared with those having survival <24 months (n=73) for 17 prognostic factors. Overall median survival was 16 months with a 5-year survival of 27%. T status (P=.000) and adjuvant chemoradiotherapy (P=.001) were independent predictors of long-term survival. Survival advantage was seen in T3N+ve disease (P=.007) with extended procedures. Complete (R0) resection was attained in 30 patients with a 5-year survival advantage of 30% as compared with incomplete (R1) resection (P=.0002). Adjuvant chemoradiotherapy improved survival in simple cholecystectomy group (P=.0008) but no advantage was seen after extended procedures. Stage III (P=.001) and node-positive disease (P=.0005) had significant benefit with adjuvant therapy. Poor differentiation and vascular invasion were associated with poor long-term survival. R0 resection was associated with prolonged survival. Extended procedures improved survival in patients with T3N+ve disease. Addition of chemoradiotherapy made significant improvement in long-term survival in stage III and node-positive lesions and in patients undergoing simple cholecystectomy. R0 resection predicted long-term survival in gall bladder cancer. T3 N+ve disease had better survival after extended procedures. Adjuvant chemoradiotherapy improved survival in stage III and node-positive disease. Poor differentiation and vascular invasion were adverse predictors of survival.  相似文献   
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Human immunodeficiency virus type 1 (HIV-1) isolates from asymptomatic homosexual men and AIDS patients were compared for their in vitro biologic and genetic properties. Most of the HIV-1 isolates from asymptomatic men, but not from AIDS patients, failed to infect CD4+ H9 cells and phytohemagglutinin-stimulated peripheral blood lymphocytes. In a longitudinal study, serial HIV-1 isolates obtained from men who seroconverted to HIV-1 and later developed AIDS were able to infect H9 cells. In contrast, longitudinal isolates from men who remained asymptomatic did not infect H9 cells. HIV-1 isolates from AIDS patients in general exhibited increased production of intracellular viral DNA, RNA, and protein as compared to isolates from asymptomatic men. Cells infected with HIV-1 isolates from asymptomatic men produced very little gp120, p24, and p55 proteins as compared to those from AIDS patients. The overall restriction patterns of HindIII, Sac-1, Pst-1, EcoR1, and BamH1 were very similar between HIV-1 isolates from asymptomatic men and those from AIDS patients. However, the restriction endonuclease pattern of BglII was quite distinct for isolates from asymptomatic men as compared to AIDS patients. Preliminary studies mapped a unique BglII site in the gag region of most of the isolates from asymptomatic men, approximately 2.0 kb from the 5' end. Thus, HIV-1 isolates from asymptomatic subjects and from AIDS patients have distinct biologic and genetic properties which may be related to the various clinical outcomes of HIV-1 infection.  相似文献   
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Summary In order to measure ejection fractions (EFs) from nuclear ventriculograms, we devised a semi-automated edge-detection technique based on a combination of inverse Fourier analysis and second-derivative techniques. Initial clinical studies showed that, for the left ventricle, our method gives EF values statistically identical with those obtained using a conventional isocontour technique. For the right ventricle, however, the values obtained using the two methods were somewhat more at variance. Despite requiring a longer processing time, the results obtained with our method are reproducible because less operator intervention is necessary.  相似文献   
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Monoclonal antibodies secreted by six hybridomas and recognizing antigenic sites on glycoproteins gC, gAB, gD, gE, and gF of herpes simplex virus type 2 were examined for their ability to protect BALB/c mice from lethal infection by the virus. Administration of monoclonal antibodies to individual glycoproteins intraperitoneally 3 h before footpad challenge with 10 times the 50% lethal dose of virus protected between 35 and 75% of the mice, except for one of two monoclonal antibodies recognizing antigens on gC. The antibodies did not neutralize virus in vitro and protected A/J mice deficient in the fifth component of complement as efficiently as complement-sufficient BALB/c mice. A good correlation was found between protection and titers of monoclonal antibodies assessed by antibody-dependent cell-mediated cytolysis. The results indicate that any of the glycoproteins can serve as antigens for a protective immune response. In addition, the data are compatible with protection being mediated by an antibody-dependent cell-mediated cytolysis mechanism.  相似文献   
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Monoclonal antibodies which reacted with type-specific antigens of herpes simplex virus type 2 or with antigens shared by herpes simplex virus types 1 and 2 were used in an indirect immunofluorescence assay to type virus isolates and to detect viral antigens in cells obtained from herpetic lesions. Complete concordance was obtained for 42 isolates typed by endonuclease restriction analysis of viral DNA and by indirect immunofluorescence with monoclonal antibodies. Examination of a limited number of ulcerative lesions revealed that indirect immunofluorescence and virus isolation were comparable in detecting herpes simplex virus. The results indicate that monoclonal antibodies can be used to accurately identify and type isolates of herpes simplex virus.  相似文献   
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PURPOSE: Patterns of failure following surgical treatment of ampullary cancers indicate that up to 45% of patients develop loco-regional recurrence. The effect of adjuvant chemo-radiotherapy on survival and loco-regional control is not yet established in this malignancy. PATIENTS AND METHODS: From January 1989 to December 2000, 113 patients underwent pancreatico-duodenectomy for ampullary cancer. One hundred and four patients who survived the operation were available for analysis to study the effect of adjuvant chemo-radiotherapy on survival and loco-regional control. Forty-nine patients received adjuvant chemo-radiotherapy (median dose 50.4 Gy with concurrent 5-Flurouracil) and long-term outcome in these patients was compared with those 55 who did not receive adjuvant therapy. RESULTS: The overall median survival was 30.1 (range 1.6-140.0) months with actuarial 1, 3 and 5-year survival rates of 79, 43 and 33%, respectively. No significant difference in median survival (34.6 vs 24.5 months; P=0.3) and actuarial 5-year survival rates (38 vs 28%) was seen between those who received and those who did not receive adjuvant therapy. Adjuvant chemo-radiotherapy did not influence the survival in high-risk patients (P=0.84), in various T and N stages and had no impact on loco-regional recurrence (P=0.6). CONCLUSIONS: Adjuvant chemo-radiotherapy did not improve the long-term survival or decrease recurrence rates in patients with ampullary cancers who had undergone pancreatico-duodenectomy.  相似文献   
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Coronary artery perforation is a known complication of percutaneous coronary intervention and potentially life threatening. Normally, these perforations are small and localized. We report the successful surgical management of a coronary artery perforation following stent insertion with extrusion of an 8-cm endarterectomy length of the circumflex coronary artery with a brief review of the recent literature.  相似文献   
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