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Children of mothers infected with human immunodeficiency virus type 1 (HIV-1) were immunized at birth and at 1, 3, and 5 months with 1 of 3 doses of recombinant gp120 vaccines prepared from SF-2 or MN strains of HIV-1. A total of 126 children were not infected; 21 received adjuvant only. Vaccine recipients developed lymphoproliferative responses on >/=2 occasions, responding more often to homologous HIV-1 antigens than did adjuvant recipients (56% vs. 14%; P<.001). Responses were appreciated after 2 immunizations and were maintained for >84 weeks after the last immunization. An accelerated immunization schedule (birth, 2 weeks, 2 months, and 5 months) with the lowest dose of the SF-2 vaccine produced responses in all 11 vaccinees by 4 weeks. Responses to heterologous envelope antigens were also detected. Immune responses to vaccination are achievable at an age when some infection (perinatal or breast milk exposure related) may be prevented.  相似文献   
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OBJECTIVE: To examine whether promoter polymorphisms associated with variation in interleukin-10 (IL-10) production are relevant to the development of rheumatoid arthritis (RA) or Felty's syndrome (FS). METHODS: DNA was obtained from 44 FS patients, 117 RA patients and 295 controls. The promoter region between -533 and - 1120 was amplified by polymerase chain reaction, and polymorphisms detected by restriction enzyme digest or sequence-specific oligonucleotide probing. RESULTS: We found no significant difference in allele or haplotype frequencies between the groups. CONCLUSION: There is no association between FS or RA and these recently identified IL-10 promoter polymorphisms. Other genetic or environmental factors could explain the alterations in IL-10 levels seen in these conditions.   相似文献   
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Gastric cancer despite a declining incidence remains a significant cause of morbidity and mortality world wide. There is strong epidemiological and histological evidence to associate Helicobacter pylori infection with the subsequent development of gastric cancer. The exact pathophysiological mechanisms involved remain to be elucidated. There is evidence to relate Helicobacter pylori infection and subsequent inflammation with an increase in gastric epithelial cell proliferation and with the induction of apoptosis. Such alterations in cellular dynamics may promote the development of mitogenic cell lines by inducing DNA damage. Studies have shown that following successful treatment, proliferation rates return to normal. At what histological stage, eradication is of benefit is less clear. It is likely that following the development of atrophy or intestinal metaplasia eradication will only slow progression. It would, therefore, seem logical, that to establish any benefit for a population, treatment should be employed at an earlier stage. As yet, an at risk group has not been identified, and as such population screening cannot be advised, mainly as a result of financial implications and the risk of promoting the development of resistant strains. Recent studies have explored the rules of bacterial factors, CagA and VacA status, host factors, HLA type, and environmental factors as determinants of outcome. Results have been variable. The establishment of an at risk group would enable selective screening and treatment, and thus prevent the development of gastric carcinoma as a result of Helicobacter pylori infection in the long-term.  相似文献   
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To screen for sinoatrial node dysfunction following the Mustard procedure for transposition of the great arteries, we studied the chronotropic response to graded maximal treadmill exercise in 29 patients at mean 6.7 years after operation. Although 93% of patients had normal resting heart rate (HR), 83% demonstrated significant depression of maximum HR and/or recovery HR after termination of exercise. These findings were similarly present among a subset of 13 patients with normal exercise tolerance. Resting and exercise-induced HR in 10 patients receiving chronic digoxin therapy were no different than in the 19 patients without medication. Sixteen patients with abnormal chronotropic responses to exercise had intracardiac electrophysiologic evaluation which confirmed sinoatrial node dysfunction in nine. Abnormal HR responses did not correlate with clinical symptoms, cardiac arrhythmias, or postoperative hemodynamics. Maximal exercise testing may be a sensitive noninvasive method to identify sinoatrial node dysfunction in postoperative children.  相似文献   
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