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91.
Three doses of inactivated hepatitis B vaccine were given at 1-month intervals to 31 hepatitis B surface antigen (HBsAg)-positive Senegalese children aged between 3 and 24 months. A control group of 18 HBsAg-positive Senegalese children received diphtheria-tetanus-polio vaccine. Immunization of HBsAg-positive infants with hepatitis B vaccine was safe but inefficient. After a 12-month follow-up, the prevalence of HBsAg chronic carriers was not significantly reduced in the hepatitis B vaccine group as compared with the control group: 48.4 and 66.7%, respectively. The presence of hepatitis B antigen was found to be a major risk factor for HBsAg-positive children to develop a chronic carrier state. The risk of developing an HBsAg chronic carrier state was also related to advancing age at time of enrollment in the study.  相似文献   
92.
93.
We report a case of acute myeloid leukemia (AML) M1 showing a 48,XY,+13,+13 karyotype. Treatment was according to the Medical Research Council AML14 trial protocol with two courses of DAT chemotherapy. Postchemotherapy bone marrow examination failed to show complete remission or cytogenetic normalization. Despite having resistant disease, the patient initially remained clinically well although requiring regular blood transfusions for anemia. However his leukocyte count gradually increased and he became symptomatic. He was treated subsequently with FLAG but died approximately 2 weeks later, 6 months after first presenting. Tetrasomy 13 as the sole cytogenetic abnormality has not been reported previously in M1 AML and has only been reported in three other AML cases, all with an immature phenotype and poor outcome.  相似文献   
94.
Defects in death receptor-mediated apoptosis have been linked to cancer and autoimmune disease in humans. The in vivo role of caspase 8, a component of this pathway, has eluded analysis in postnatal tissues because of the lack of an appropriate animal model. Targeted disruption of caspase 8 is lethal in utero. We generated mice with a targeted caspase 8 mutation that is restricted to the T-cell lineage. Despite normal thymocyte development in the absence of caspase 8, we observed a marked decrease in the number of peripheral T-cells and impaired T-cell response ex vivo to activation stimuli. caspase 8 ablation protected thymocytes and activated T-cells from CD95 ligand but not anti-CD3-induced apoptosis, or apoptosis activated by agents that are known to act through the mitochondria. caspase 8 mutant mice were unable to mount an immune response to viral infection, indicating that caspase 8 deletion in T-cells leads to immunodeficiency. These findings identify an essential, cell-stage-specific role for caspase 8 in T-cell homeostasis and T-cell-mediated immunity. This is consistent with the recent identification of caspase 8 mutations in human immunodeficiency.  相似文献   
95.
BACKGROUND: Since the advent of combined antiretroviral therapy in 1996, substantial decreases in HIV-related morbidity and mortality have been observed in the United States and other developed countries. To assess the effects on overall survival and for specific AIDS-defining illnesses (ADIs), survival among persons with AIDS (PWAs) in New York City (NYC) before and after the introduction of combination therapy was investigated. METHODS: Survival among 79,878 PWAs diagnosed between 1990 and 1998 and reported through March 2001 was estimated. Cumulative survival at 24 months among PWAs was estimated by actuarial methods, and Cox proportional hazards model adjusted for covariates was used to estimate the relative hazard (RH) of death for specific ADIs over time. RESULTS: Overall cumulative survival at 24 months increased from 43% among PWAs diagnosed during 1990-1995 to 76% for those diagnosed 1996-1998. Improving survival for all ADIs was found among PWAs diagnosed after 1995, but changes for immunoblastic lymphoma, primary lymphoma of the brain, and invasive cervical cancer were only moderate and were statistically (p >.05) insignificant. Burkitt lymphoma, immunoblastic lymphoma, invasive cervical cancer, and primary lymphoma of the brain had the highest RH of death among PWAs diagnosed after 1995. CONCLUSIONS: Substantial improvements in survival after 1995 were found for all PWAs but varied by gender, race, risk, socioeconomic status, and specific ADIs. Consistent with other studies, neoplastic ADIs have shown less improvement than other diseases after 1995. The relatively poor outcome of PWAs with neoplastic diseases requires further investigation.  相似文献   
96.
Cholesterol crystal embolization (CCE) is a severe systemic disorder caused by vascular migration of cholesterol crystals originating from ulcerative atherosclerotic plaques located in large arteries. We report 2 cases of CCE diagnosed on bladder transurethral resection in 2 men aged 94 and 72 years. Both patients had atherosclerosis disease. One patient had been treated by heparin 1 month before for pulmonary embolism and the other had had a coronary angiography and bypass graft surgery 5 months before for silent myocardial infarction. One patient presented with hematuria and the other with acute renal failure. Cystoscopy showed multiple papillary tumors of the bladder wall. Bladder transurethral resections showed transitional cell carcinoma with cholesterol crystals occluding the lumen of small arterioles in the submucosa. Eight cases of CCE in the bladder wall have been reported in the literature in 3 women and 5 men aged 56 to 79 years. Cholesterol crystal embolization is often discovered in the bladder wall on necropsy specimens. Only 2 cases have been fortuitously discovered on bladder transurethral resection performed for transitional cell carcinoma. Cholesterol crystal embolization in the bladder wall is often a marker of severe disease although the evolution is quite favorable in our patients, still alive 1 and 2 years after diagnosis.  相似文献   
97.
Genetic linkage studies have provided significant evidence thata major gene defect, AD3, for familial early-onset Alzheimer'sdisease (EOAD) is located at chromosome 14q24.3, between theshort tandem repeat (STR) markers D14S52 and D14S53 defininga genetic size of 22.7 cM for the AD3 candidate region. We constructeda physical map of the AD3 region using yeast artificial chromosomes(YACs) selected from both the CEPH and megaCEPH YAC librariesusing the AD3 linked STR markers as well as new sequence-taggedsites (STSs) designed based on YAC terminal sequences. The YACmap is contiguous in the region between D14S258 and D14S53,a region of 8.2 cM, and has an estimated physical size of 4–8Mb. The YAC contig map was used as a framework to localize threeknown genes, a pseudogene and two brain expressed sequence tags(ESTs). Linkage analysis studies in two Belgian chromosome 14EOAD families AD/A and AD/B, identified obligate recombinantsin family AD/A with D14S289 and D14S61 reducing the geneticsize of the candidate AD3 region substantially. The minimalAD3 candidate region measured 6.4 cM on the genetic map andis contained within six overlapping megaCEPH YACs that covereda physical distance estimated between 2 and 6 Mb. These YACsas well as other YACs in the YAC contig map are valuable resourcesin gene cloning efforts or genomic sequencing experiments aimingat isolating the AD3 gene.  相似文献   
98.
BACKGROUND: Results of conservative management of epithelial ovarian cancer (EOC) remain controversial in the literature. The aim of this study was to assess the clinical outcomes and fertility following fertility-sparing surgical management of EOC in a retrospective multicentre study. METHODS: A multicentre retrospective study was performed by members of two French groups. Six inclusion criteria were defined: (i) Histological review by the same pathologist; (ii) age < or =40 years; (iii) conservative management; (iv) complete peritoneal staging; (v) delivery of a platinum-based chemotherapy in stage > or = IC; and (vi) follow-up >1 year. RESULTS: Thirty-four patients fulfilled the inclusion criteria: 30 had stage IA disease; three had stage IC and one had stage IIA. Eleven patients had recurrence: 10 patients had invasive disease and one had borderline recurrence. Among 10 patients with invasive recurrence, initial stage and grade were: stage IA G1, n = 1; stage IA G2, n = 4; stage IA G3, n = 1; and stage> or = IC, n = 4. All patients with stage > IA had recurrence. Ten pregnancies were observed in nine patients. CONCLUSION: Conservative surgery for patients with EOC could be considered in young patients with stage IA G1 disease. This procedure should not be performed in patients with FIGO stage > IA.  相似文献   
99.
We report on three patients with Costello syndrome and isolated growth hormone (GH) deficiency treated with biosynthetic GH. To our knowledge, these are the only patients with Costello syndrome who have been successfully treated for GH deficiency. We review the pathophysiology of Costello syndrome and highlight the recent recommendations of tumor screening and cardiac surveillance in this population, of particular relevance to those receiving GH therapy.  相似文献   
100.
We have investigated the density of peptides required to elicit different biological responses in cytotoxic T lymphocytes (CTL), including trogocytosis (i.e., the phenomenon whereby the lymphocytes actively capture fragments of plasma membrane from those cells with which they establish an immune synapse). We have used two separate mouse models of CTL recognising defined peptides presented by MHC class I molecules. In both systems, triggering of cytotoxicity and capture of membrane components reached saturation with low densities of ligand. On the other hand, down-modulation of cell-surface levels of TCR, induction of IFN-gamma production and detection of peptide captured required much higher ligand densities. Interestingly, fratricide (i.e., killing between CTL sharing the same specificity), a mechanism proposed to account for CTL exhaustion, was detected only at antigen concentrations still well above that second threshold leading to full blown activation. Taken together, our results show that the different thresholds that govern the elicitation of different CTL functions correlate with different proportions of antigen among the target cell components being captured via trogocytosis.  相似文献   
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