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Study Objective . To determine the efficacy of high-dose ascorbate supplementation in lowering lipoprotein(a) [Lp(a)] levels in patients with premature coronary heart disease (CHD). Design . Randomized, double-blind, placebo-controlled trial. Setting . Outpatient clinic. Patients . Forty-four patients with documented premature CHD. defined as confirmed myocardial infarction and/or angiographically determined stenosis of 50% or greater in at least one major coronary artery before age 60 years. Interventions . Patients were block randomized on the basis of age, gender, and screening Lp(a) concentrations to receive ascorbate 4.5 g/day or placebo for 12 weeks. Measurements and Main Results . High-dose ascorbate was well tolerated and produced a marked elevation in mean plasma ascorbate levels (+1.2 mg/dl; p<0.001). Multiple linear regression analysis revealed no significant effect of supplementation on postintervention Lp(a) levels (p=0.39) in a model that included treatment group assignment, and baseline Lp(a) levels. Conclusions . Our findings do not support a clinically important lowering effect of high-dose ascorbate on plasma Lp(a) in patients with premature CHD.  相似文献   
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Final year residents in training in Louisiana were surveyed regarding plans for medical practice and their perceptions of the importance of various factors in choosing practice locations. Most specialty groups selected smaller communities at similar rates. Growing up in small towns is associated with wanting to practice in small towns while concerns about opportunities for the family and income of the region are associated with wanting to practice in a larger city.This study was supported by the Louisiana Council for Statewide Planning for Physician Manpower through Contract No. 23058, Louisiana Department of Health and Human Resources.Ms. Samaha is a data analyst for the Louisiana Council for Statewide Planning for Physician Manpower; Robert R. Franklin, M.D. is Executive Secretary of the Council and Assistant Professor, Department of Biostatistics and Epidemiolgy, Tulane University School of Public Health and Tropical Medicine; Janet C. Rice is Assistant Pofessor, Department of Biostatistics and Epidemiology at the Tulane University School of Public Health and Tropical Medicine, New Orleans, Louisiana 70112.  相似文献   
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A 25–year-old woman was admitted to the hospital because of rising trough cyclosporine concentrations thought to be due to self-administration of 4 times the normal dosage of the drug for 8 days. Her symptoms included colicky central abdominal pains and urinary retention; her serum creatinine concentrations were elevated. Whole blood cyclosporine and metabolite concentrations were measured by high-performance liquid chromatography and monoclonal radioimmunoassays. The highest reported trough cyclosporine concentration was 5877 ng/ml, and AM1 (M17) concentration was 3425 ng/ml. A cyclosporine half-life of 91 hours was calculated. Nine days after the agent was discontinued the patient's serum creatinine concentration had returned to normal and her symptoms resolved. Due to the availability of three sizes of cyclosporine capsules, and the need for frequent dosage changes, continued vigilance is necessary to ensure that patients understand their drug regimen.  相似文献   
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The effect of weight loss with anorectic medications on sleep apnea, non-insulin-dependent diabetes, and steatohepatitis is illustrated in three cases from practice in a clinical nutrition setting. Prevention of obesity, a chronic disorder, is preferable, but when obesity becomes a major obstacle in the care of patients with respiratory, cardiovascular, and metabolic disorders and osteoarthritis, an intense course of weight reduction using anorectic medications under medical and dietetic guidance is essential for patients' survival and reduction of medical cost.  相似文献   
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The present paper introduces the concept of the narcissistically vulnerable system by suggesting that organizations may manifest some of the same pathological characteristics as narcissistic individuals. The public mental hospital was chosen as an example of such a system. Reasons for its vulnerability were suggested and specific defenses, employed at the system level, were discussed. Finally, remedies for the repair of the narcissistically vulnerable system were considered.  相似文献   
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Continuous arteriovenous hemodiafiltration (CAVHD) is being used increasingly in critically ill patients with acute renal failure (ARF). We prospectively evaluated extracorporeal and total systemic clearances (ClCAVHD and Cls) of ciprofloxacin during CAVHD in four patients with severe ARF to assess the adequacy of drug dosing. Ciprofloxacin serum and ultrafiltrate concentrations were measured by high-performance liquid chromatography. The ClCAVHD accounted for approximately 5.9% (range 2.8–11.6%) of Cls of ciprofloxacin. However, large variability in serum concentrations was observed with the normally recommended dose of 400 mg/day, and doses of up to 800 mg/day were required to maintain concentrations suitable for treatment of serious infections. High daily doses of ciprofloxacin required in these patients are likely related to altered pharmacokinetics in serious illness as well as to the increased extracorporeal clearance during CAVHD. Clinical studies to define appropriate dosing recommendations for ciprofloxacin during CAVHD are necessary to guide clinicians in optimum drug use.  相似文献   
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In addition to its certification programme, which assesses the readiness of foreign medical graduates to enter graduate medical education programmes in the USA, the Educational Commission for Foreign Medical Graduates (ECFMG) is involved in a number of other programmes in international medical education. These include: (1) continuing to provide sponsorship for exchange visitors in graduate medical education programmes in the USA; (2) the development of a clinical skills assessment that is currently being introduced in pilot projects in the USA and abroad and will eventually become a component of the ecfmg certification process; (3) funding and administration of two fellowship programmes that provide foreign scholars (clinicians and basic scientists) with the opportunity to spend up to one year in a US medical school; (4) collaboration with the World Health Organization on the upcoming revised edition of the World Directory of Medical Schools ; and (5) co-sponsorship, with the World Health Organization, of a consultation on quality medical education oriented towards attaining a global consensus on the definition and the elements of quality in medical education and on the most appropriate ways to evaluate quality.  相似文献   
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Severe acute respiratorysyndrome coronavirus-2 (SARS-CoV-2) pandemic spread rapidly and this scenario is concerning worldwide, presenting more than 590 million coronavirus disease 2019 cases and 6.4 million deaths. The emergence of novel lineages carrying several mutations in the spike protein has raised additional public health concerns worldwide during the pandemic. The present study review and summarizes the temporal spreading and molecular evolution of SARS-CoV-2 clades and variants worldwide. The evaluation of these data is important for understanding the evolutionary histories of SARSCoV-2 lineages, allowing us to identify the origins of each lineage of this virus responsible for one of the biggest pandemics in history. A total of 2897 SARS-CoV-2 whole-genome sequences with available information from the country and sampling date (December 2019 to August 2022), were obtained and were evaluated by Bayesian approach. The results demonstrated that the SARS-CoV-2 the time to the most recent common ancestor (tMRCA) in Asia was 2019-12-26 (highest posterior density 95% [HPD95%]: 2019-12-18; 2019-12-29), in Oceania 2020-01-24 (HPD95%: 2020-01-15; 2020-01-30), in Africa 2020-02-27 (HPD95%: 2020-02-21; 2020-03-04), in Europe 2020-02-27 (HPD95%: 2020-02-20; 2020-03-06), in North America 2020-03-12 (HPD95%: 2020-03-05; 2020-03-18), and in South America 2020-03-15 (HPD95%: 2020-03-09; 2020-03-28). Between December 2019 and June 2020, 11 clades were detected (20I [Alpha] and 19A, 19B, 20B, 20C, 20A, 20D, 20E [EU1], 20F, 20H [Beta]). From July to December 2020, 4 clades were identified (20J [Gamma, V3], 21 C [Epsilon], 21D [Eta], and 21G [Lambda]). Between January and June 2021, 3 clades of the Delta variant were detected (21A, 21I, and 21J). Between July and December 2021, two variants were detected, Delta (21A, 21I, and 21J) and Omicron (21K, 21L, 22B, and 22C). Between January and June 2022, the Delta (21I and 21J) and Omicron (21K, 21L, and 22A) variants were detected. Finally, between July and August 2022, 3 clades of Omicron were detected (22B, 22C, and 22D). Clade 19A was first detected in the SARS-CoV-2 pandemic (Wuhan strain) with origin in 2019-12-16 (HPD95%: 2019-12-15; 2019-12-25); 20I (Alpha) in 2020-11-24 (HPD95%: 2020-11-15; 2021-12-02); 20H (Beta) in 2020-11-25 (HPD95%: 2020-11-13; 2020-11-29); 20J (Gamma) was 2020-12-21 (HPD95%: 2020-11-05; 2021-01-15); 21A (Delta) in 2020-09-20 (HPD95%: 2020-05-17; 2021-02-03); 21J (Delta) in 2021-02-26 (2020-11-02; 2021-04-24); 21M (Omicron) in 2021-01-25 (HPD95%: 2020-09-16; 2021-08-08); 21K (Omicron) in 2021-07-30 (HPD95%: 2021-05-30; 2021-10-19); 21L (Omicron) in 2021-10-03 (HPD95%: 2021-04-16; 2021-12-23); 22B (Omicron) in 2022-01-25 (HPD95%: 2022-01-10; 2022-02-05); 21L in 2021-12-20 (HPD95%: 2021-05-16; 2021-12-31). Currently, the Omicron variant predominates worldwide, with the 21L clade branching into 3 (22A, 22B, and 22C). Phylogeographic data showed that Alpha variant originated in the United Kingdom, Beta in South Africa, Gamma in Brazil, Delta in India, Omicron in South Africa, Mu in Colombia, Epsilon in the United States of America, and Lambda in Peru. The COVID-19 pandemic has had a significant impact on global health worldwide and the present study provides an overview of the molecular evolution of SARS-CoV-2 lineage clades (from the Wuhan strain to the currently circulating lineages of the Omicron).  相似文献   
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