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Multiple human immunodeficiency virus type 1 (HIV-1) genetic subtypes, intersubtype recombinants, and group O have been found in west central Africa. In Nigeria, where HIV-1 prevalence is rising rapidly, characterization of HIV-1 strains has been limited. Each of three full-length genome sequences acquired to date shows evidence of recombination: two are largely subtype G with subtype A segments in the midgenome accessory region; the third, IbNG, is subtype G with the long terminal repeats and two segments of pol from subtype A. In this study, peripheral blood mononuclear cells obtained in 1994-1995 from 10 patients hospitalized in northeastern Nigeria were evaluated by sequencing of the complete envelope and, from 7 patients, a portion of gag. Four patients harbored subtype G viruses and six patients had recombinant viruses. Two had strains sharing the A/G recombinant structure of IbNG. Two had a previously undescribed recombinant, mostly subtype A, whose carboxyl-terminal gp41 could not be classified. An A/G recombinant different from IbNG but similar to CA1, a Cameroonian strain, was found in one patient. The remaining patient had a strain that was otherwise subtype G but shared an unclassified carboxyl-terminal gp41 segment with the CA1-like strains. Other subtypes and group O were not found.  相似文献   
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BACKGROUND: Data from large, multicenter, US studies determining the efficacy of triple therapy for the eradication of Helicobacter pylori are lacking, especially for a treatment duration of less than 14 days. METHODS: Patients with H pylori infection and active duodenal ulcer disease or a history of duodenal ulcer disease within the past year were randomized to receive 30 mg of lansoprazole, 1 g of amoxicillin, and 500 mg of clarithromycin twice daily for 10 or 14 days. The primary efficacy end point was the eradication of H pylori as confirmed by negative histological and culture results at 4 to 6 weeks after the completion of treatment. RESULTS: Of 284 patients enrolled in the study from 46 US sites, 236 met the entry criteria. At 4 to 6 weeks after the end of therapy, H pylori was eradicated in 85% (96/ 113) of the patients receiving 14-day triple therapy and in 84% (103/123) of those receiving 10-day triple therapy by per-protocol analysis (95% confidence interval for treatment group differences, -10.5 to 8.1; P>.05). There was also no significant difference between the 14- and 10-day treatment groups when analyzed by an intent-to-treat analysis of H pylori eradication. A similar proportion of patients in each treatment group reported an adverse event related to therapy (34% [46/136] vs 38% [56/148], respectively). CONCLUSIONS: In patients with an active or a recent history of duodenal ulcer, lansoprazole-based triple therapy for 10 or 14 days is highly effective in the eradication of H pylori. The duration of therapy may be reduced from 14 to 10 days without a significant effect on regimen efficacy.  相似文献   
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SIFs on a circular crack due to distributed tractions are given by singular integrals over the crack surface. Surrounding the singularity point by a small (almost) semicircular region, we evaluate the singular part of the integral in a universal closed form. This leads to an accurate and numerically trivial procedure. It is also extended to moderately non-circular cracks. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
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