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Abstract: HLA-J345, in contrast to B44, does not show molecular polymorphism. We have found a group of Caucasian Spanish individuals, sero-logically typed as B45, showing an unexpected HLA-B12 PCR-SSO subtyp-ing pattern. Complete coding region sequencing and B45 subtyping by PCR-SSO demonstrated that the j345 serologic specificity is constituted by two molecular alleles: B*4501 and B*5002. B*5002 is recognized by polyclonal and monoclonal allosera against B12 and B45, whereas it is not detected by B21, B49, or B50 reagents, providing a new example of poor correlation between serology and structure. B*5002 explains an important subset (18%) of the B45-positive individuals of the Spanish population studied, and almost half are included in a very infrequent haplotypic association, Cw6-B*5002-DRB1*0406-DQA1*03-DQB1*0402.  相似文献   
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BACKGROUND: Testing for human papillomavirus (HPV) DNA is more sensitive but less specific than cytological analysis. Loss in specificity is most relevant in women younger than 35 years because of increased HPV prevalence. We aimed to compare conventional screening with an experimental strategy in women aged 25-34 years, and investigate the effect of different criteria of referral to define the best methods of HPV screening. METHODS: Women were randomly assigned to the conventional procedure (standard cytology, with referral to colposcopy if cytology showed atypical squamous cells of undetermined significance or more [ASCUS+]) or an experimental procedure (liquid-based cytology and testing for high-risk HPV types, with referral to colposcopy with ASCUS+ cytology). Women positive for HPV (cutoff > or = 1 pg/mL) but with normal cytology were retested after 1 year. The main endpoint was the presence of cervical intraepithelial neoplasia at grade 2 or more (CIN2+) in reviewed histology. The main analysis was by intention to screen. This trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN81678807. FINDINGS: We randomly assigned 5808 women aged 25-34 years to the conventional group and 6002 to the experimental group. The experimental procedure was significantly more sensitive than the conventional procedure (55 vs 33 CIN2+ lesions detected; relative sensitivity 1.61 [95% CI 1.05-2.48]), but had a lower positive predictive value (PPV; relative PPV 0.55 [0.37-0.82]). HPV testing (> or = 1 pg/mL) with cytology triage was also more sensitive than conventional cytology (relative sensitivity 1.58 [1.03-2.44], relative PPV 0.78 [0.52-1.16]). Relative PPV could be improved, with minimum loss in sensitivity, by use of a 2 pg/mL cutoff for HPV testing. Compared with conventional cytology, liquid-based cytology had a relative sensitivity of 1.32 (0.84-2.06), relative PPV 0.58 [0.38-0.89]). INTERPRETATION: HPV testing alone with cytology triage could be a feasible alternative to conventional cytology for screening women younger than 35 years. Follow-up will provide data on possible overdiagnosis and on the feasibility of extended intervals.  相似文献   
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Cohen syndrome is a hereditary disorder transmitted as an autosomal-recessive trait. Approximately 100 cases have been reported in the genetic and pediatric literature. Despite the fact that oral alterations are often observed in these cases, only 1 work has been published addressing this specific topic, and it tended to concentrate on periodontal abnormalities. The present study details 2 new patients, 2 brothers (8 and 11 years old), and mainly consists of an analysis of the dentomaxillary anomalies that until now have not been studied in depth. In this study, the mandible, characterized as hypoplastic in Cohen syndrome, appears to be in a normal position; what really exists is a maxillary hyperplasia of genetic origin. We also put forward an observation hitherto undescribed in the literature: dental agenesis.  相似文献   
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Air vs. He-O2 (20.9% O2) recompression treatment was examined in a model of severe decompression sickness (DCS) using male albino guinea pigs (Cavia porcellus, 500-600 g). Following decompression to the surface from simulated air dives at 200 or 250 fsw, both anesthetized and unanesthetized animals often exhibited responses indicative of a fatal bout of DCS (including hypotension, cardiac arrhythmia, and tachypnea). Upon recompression with air back to depth, good recovery of animals with DCS was observed. Comparison of air vs. He-O2 recompression responses of unanesthetized animals with recompression back to initial depth (200 fsw) revealed a slower recovery from tachypnea with He-O2. Recompression partially back to depth following 200-fsw air dives produced significant differences in the breathing recovery vs. recompression depth relationship between air and He-O2. Treatment effectiveness improved with increasing depth with air, but not with He-O2. These data indicate potential differences in recompression response to air vs. He-O2 when using ventilatory recovery as a measure of effectiveness in treatment of DCS in guinea pigs following air dives.  相似文献   
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