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91.
Waldo CR McFarland W Katz MH MacKellar D Valleroy LA 《Journal of acquired immune deficiency syndromes (1999)》2000,24(2):168-174
OBJECTIVES: To compare HIV seroprevalence and sexual risk behavior among very young gay and bisexual men (aged 15-17 years) and their older counterparts (aged 18-22 years). To examine drug-use patterns and correlates of sexual risk behavior in both of these age groups. DESIGN AND METHODS: An interviewer-administered cross-sectional survey of 719 gay and bisexual males between 15 and 22 years old was conducted through a venue-based sampling design. Blood specimens were collected and tested for HIV antibodies, hepatitis B, and syphilis. Interviews assessed sexual and drug-use behavior as well as psychosocial variables believed to be related to sexual risk-taking, including self-acceptance of gay or bisexual identity, perceptions of peer norms concerning safer sex, and perceptions of the ability to practice safer sex (safer sex self-efficacy). RESULTS: Of the 719 participants, 100 (16.2%) were aged between 15 and 17 years. HIV seroprevalence was somewhat lower among those aged 15 to 17 years (2.0%) compared with those aged 18 to 22 years (6.8%). Overall, the prevalence of hepatitis-B core antibody was significantly lower in the younger age group (5.0%) than in the older group (14.1%). The men aged 15 to 17 years used alcohol, ecstasy, and heroin less frequently than those aged 18 to 22 years. The age groups did not differ in the proportion of men who reported any unprotected anal intercourse in the previous 6 months (31.2%). In both age groups, use of amphetamines, ecstasy, and amyl nitrate was associated with unprotected anal intercourse. Self-acceptance of gay or bisexual identity was related to less sexual risk for those aged 15 to 17 years. In both age groups, greater safer sex self-efficacy was linked to less HIV sexual risk-taking. In the younger group, perceptions of peer norms that support safer sex were related to less risk behavior. CONCLUSIONS: Very young gay and bisexual men engage in unprotected anal sex at rates comparable with those for their somewhat older counterparts, raising serious concern over their risk of acquiring HIV infection. To prevent seroconversions, interventions must target those <18 years of age, and prevention programs should address the use of certain drugs in relation to sex and sexual risk-taking. To be most effective, programs should develop innovative communication strategies to take into account lack of self-acceptance of gay or bisexual identity and low self-efficacy for practicing safer sex. 相似文献
92.
Pratt CM Camm AJ Bigger JT Breithardt G Campbell RW Epstein AE Kappenberger LJ Kuck KH Pocock S Saksena S Waldo AL 《Journal of cardiovascular electrophysiology》1999,10(11):1534-1549
There are a number of novel ways in which implantable cardioverter defibrillator (ICD) endpoints can be used in clinical trials to evaluate antiarrhythmic drugs. The advances in ICD technology (storage, retrieval, and accurate interpretation of ICD electrograms) expand the potential to include the use of an ICD endpoint as a clinical surrogate for sudden death. The ICD also provides the necessary safety net to test new drugs. The frequent need for antiarrhythmic drugs in patients already fitted with an ICD (e.g., for atrial fibrillation) necessitates knowledge of the drugs' effect on defibrillator threshold. There are interpretative problems and challenges associated with all types of ICD trials. A particular difficult issue is the degree to which the results of data on antiarrhythmic drug efficacy and safety acquired in the context of an ICD endpoint trial might be extrapolated to patient populations in which the device is not used. These and other challenging issues are discussed, with the goal of enhancing the design and interpretation of clinical trials featuring ICD endpoints. 相似文献
93.
This study evaluated the accuracy of the interpretation of the chest film in delineating localised abnormalities of ventilation and perfusion, as well as the overall severity of airways obstruction, exercise tolerance, and clinical condition in children with cystic fibrosis. Radiographic findings in various regions of the chest film were compared with the functional values obtained with regional lung function tests which evaluated the arrival and disappearance of boluses of radioactive nitrogen given by inhalation and infusion. While the more severely affected areas on the chest radiograph were found to correlate with similar regions on the lung function tests, as did overall scores, errors occurred in some cases if the x-ray film alone was used as a judge of regional physiological derangement. In addition the degree of airways obstruction, the exercise tolerance on a cycle ergometer, and clinical grading, each correlated significantly with the radiographic score. We conclude that the chest radiograph is a good indicator of the overall severity of the lung disease and that it correlates well with exercise tolerance and clinical condition in cystic fibrosis. 相似文献
94.
Ehud Krongrad Carl N. Steeg Alan J. Hordof Albert L. Waldo Welton M. Gersony 《Pediatric cardiology》1980,1(3):185-191
Summary Responsiveness to rapid atrial pacing of the specialized atrioventricular (A-V) conduction system was studied in 25 patients aged 2 months to 18 years. Atrial pacing via a catheter placed at the right atrial superior vena cava junction was initiated at rates slightly greater than the sinus rate and gradually increased to rates as high as 600 stimuli per minute. His bundle electrograms were obtained in most patients. When the atrial pacing rate (x-axis) was plotted against the corresponding ventricular rate (y-axis), the curve was M-shaped. The initial ascending limb occurred during 1:1 A-V conduction with rates as high as 270 stimuli per minute. The first descending limb resulted from Wenckebach type A-V block occurring at rates of 160 to 300 stimuli per minute. The second ascending limb corresponded to periods of 2:1 A-V block observed at rates of 200 to 536 stimuli per minute, and the final descending limb was related to higher degrees of block at both the pacing site and the A-V node. The second descending limb was seen with pacing rates of 296 to 600 stimuli per minute. The rates required to produce Wenckebach type A-V block in this group of children were higher than those reported in adults. One patient with spontaneous first-degree A-V block developed 2:1 A-V block at a pacing rate of only 150 stimuli per minute.This technique for studying the response to rapid atrial pacing of the specialized A-V conduction system characterises its functional capacity. The technique can be applied rapidly and safely in selected patients. 相似文献
95.
Scintiscans of liver and spleen using technetium 99m sulphur colloid in 15 infants with extrahepatic biliary atresia and 11 infants with severe obstructive jaundice (7 with genetic deficiency of alpha 1-antitrypsin) showed similar hepatic size, pattern of isotope uptake, and splenic abnormality with no distinguishing features. In 37 older children with a variety of liver disorders, the scan was invaluable in showing filling defects in five instances. Selenomethionine was taken up not only by the two filling defects due to hepatoblastoma but also in a haemangioendothelioma. In the remaining patiens liver scanning confirmed hepatic abnormality and the necessity for more specific invasive diagnostic investigations. 相似文献
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99.
Lazenby HC Levit KR Waldo DR Adler GS Letsch SW Cowan CA 《Health care financing review》1992,13(4):89-103
The national health accounts (NHA) are the framework within which type of services and sources of funding for health care expenditures are measured. NHA, devised to portray the structure of health care delivery and financing in the United States, provide essential information necessary for the formulation of public health policy and for international comparison. In this article, the authors describe the importance of the NHA nationally and internationally, and provide a blueprint of the definitions, sources, and methods used to create this system of NHA in the United States. 相似文献
100.
Fahmi A. AL-Kaf Turki A. AL Garni Nahes AL-Harbi Hassan Sandokji Sondos Samargandy 《Journal of the Saudi Heart Association》2021,33(1):71
A 21-years-old with Down syndrome presented with respiratory distress. Initial investigations revealed a cardiac tamponade. On further evaluation, he had positive coronavirus disease-2019 (COVID-19), severe chest infection and severe hypothyroidism. He responded well to urgent pericardiocentesis, levothyroxine, hydrocortisone and tocilizumab. 相似文献