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Euzebiusz Jamrozik Katherine Littler Susan Bull Claudia Emerson Gagandeep Kang Melissa Kapulu Elena Rey Carla Saenz Seema Shah Peter G Smith Ross Upshur Charles Weijer Michael J Selgelid 《Vaccine》2021,39(4):633-640
This report of the WHO Working Group for Guidance on Human Challenge Studies in COVID-19 outlines ethical standards for COVID-19 challenge studies. It includes eight Key Criteria related to scientific justification, risk-benefit assessment, consultation and engagement, co-ordination of research, site selection, participant selection, expert review, and informed consent. The document aims to provide comprehensive guidance to scientists, research ethics committees, funders, policymakers, and regulators in deliberations regarding SARS-CoV-2 challenge studies by outlining criteria that would need to be satisfied in order for such studies to be ethically acceptable. 相似文献
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Five boys with familial cytomegalic adrenocortical hypoplasia have been followed up for an average of 19 years. Despite treatment with replacement corticosteroids, all 5 failed to show a spontaneous onset of puberty and, when assessed at ages 13 to 19 years, all had both sexual infantilism and skeletal immaturity. Hypogonadism was confirmed by low levels of plasma testosterone, and pituitary reserve of gonadotrophin was shown to be inadequate by testing with gonadotrophin-releasing hormone. Two boys, both with adequate testosterone output on human chorionic gonadotrophin stimulation, were given gonadotrophin therapy, whereas the other 3 were treated with parenterally administered testosterone. With treatment, all 5 patients showed advances in pubertal staging. Although the mechanism of the hypogonadotropism remains unclear, the association of hypogonadotrophic hypogonadism with familial cytomegalic adrenocortical hypoplasia appears to be a constant one and may be considered as a treatable inherited syndrome of pubertal failure. 相似文献
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Intermittent claudication, a symptom of atherosclerosis in the large vessels of the lower limbs, greatly affects patient mobility and quality of life. Medical therapy for a moderate form of this condition includes vasodilators, antiplatelet agents and alternative treatments such as ginkgo biloba.A meta-analysis of results from 52 trials (including 5088 patients) was conducted for all current medical therapies for intermittent claudication. After 24 weeks, some of the medical therapies were found to be more effective than placebo for the primary end-points of either pain-free walking distance or maximum walking distance. Vasodilators presented the best results in walking distance. Pentoxifylline offered better results than naftidrofuryl, although the treatment benefit, measured in additional metres walked with treatment than without, was modest. Antiplatelets, ginkgo biloba and levocarnitine were slightly more effective than placebo, although the treatment benefit was of limited clinical importance. On average, patients walked 60m further with therapy than without, and only about half of that added distance was pain-free. Very little consistent information was available for other clinical end-points, such as overall mortality and adverse effects. These data suggest that some of the medical therapy, pentoxifylline in particular, can only modestly increase functional status in patients with moderate intermittent claudication. There is a need for uniformity in research design and reporting of trials. A future trial comparing medical therapy with physical therapy is indicated. 相似文献
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Saenz RB 《American family physician》1999,59(7):1754, 1756
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Diagnosis of mediastinal masses in pediatric patients using mediastinoscopy and the Chamberlain procedure 总被引:3,自引:0,他引:3
Glick RD Pearse IA Trippett T Saenz NC Ginsberg RJ La Quaglia MP 《Journal of pediatric surgery》1999,34(4):559-564
BACKGROUND/PURPOSE: Mediastinal masses commonly are referred to the pediatric surgeon and can be difficult diagnostic problems. Various techniques have been used to perform biopsy in the mediastinum, but there are few reports of mediastinoscopy or Chamberlain procedure in children in the literature. The authors reviewed their experience with these techniques in a pediatric oncology population. METHODS: The medical records of all patients on the pediatric surgical service between 1987 and 1997, inclusive, who underwent mediastinoscopy or Chamberlain procedure were reviewed. Demographic data, diagnostic accuracy, complications, operating time, and blood loss were recorded. RESULTS: Sixteen consecutive patients underwent 13 Chamberlain procedures and six mediastinoscopies over the above period. Diagnostic accuracy was found to be 95% overall (100% for Chamberlain procedure, 83% for mediastinoscopy). Five complications occurred in the Chamberlain group and none in the mediastinoscopy group. No complication required thoracotomy or sternotomy. Among patients whose sole reason for admission was diagnosis of a mediastinal mass, the mean hospital stay was 1.7+/-0.8 days (n = 7) for those who underwent Chamberlain procedure and 1.4+/-0.9 days (n = 4) for those who underwent mediastinoscopy. One mediastinoscopy was performed as an ambulatory procedure. CONCLUSION: Mediastinoscopy and the Chamberlain procedure are effective and safe techniques for biopsy of mediastinal masses in this age group. 相似文献