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961.
962.
963.
964.
Acute myocardial infarction in previously healthy children is rare in the absence of congenital anomalies. We describe two cases of acute anterior myocardial infarction in adolescent males with no congenital heart disease, without prior history of or risk factors for coronary heart disease, and with no history of drug abuse. These cases illustrate that myocardial infarction in the absence of systemic illness or coronary anomalies can occur in an adolescent population.  相似文献   
965.
Once onset of clinical rabies develops in an individual, death is inevitable. Thus, it is imperative that, for persons exposed or potentially exposed to rabies virus, prophylaxis must be instituted as soon as possible following the exposure. Local wound management is an essential part of postexposure rabies prophylaxis. Exposed persons should receive a recommended series of a tissue culture or cell culture origin vaccine. The number of doses and route of vaccination differ in various regions of the world and are discussed in the text. The administration of a rabies immune globulin is generally recommended in conjunction with the first dose of the rabies vaccine. Nerve tissue origin vaccines, although used extensively in some parts of the world, are not recommended if cell or tissue culture vaccines are available. Decision trees are presented in the text to aid in determining if rabies vaccine is necessary following a known or presumed exposure to the virus, along with a table outlining the various rabies vaccines available in the World. Rabies pre-exposure immunisation is recommended for those individuals at risk of exposure to the virus. Pre-exposure prophylaxis consists of 3 doses of an approved rabies vaccine administered either intramuscularly or intradermally on days 0, 7, and 21 or 28 with periodic booster doses or titre determination depending on the level of risk of potential exposure to the virus.  相似文献   
966.
BACKGROUND: Chiropractic spinal manipulation has been reported to be of benefit in nonmusculoskeletal conditions, including asthma. METHODS: We conducted a randomized, controlled trial of chiropractic spinal manipulation for children with mild or moderate asthma. After a three-week base-line evaluation period, 91 children who had continuing symptoms of asthma despite usual medical therapy were randomly assigned to receive either active or simulated chiropractic manipulation for four months. None had previously received chiropractic care. Each subject was treated by 1 of 11 participating chiropractors, selected by the family according to location. The primary outcome measure was the change from base line in the peak expiratory flow, measured in the morning, before the use of a bronchodilator, at two and four months. Except for the treating chiropractor and one investigator (who was not involved in assessing outcomes), all participants remained fully blinded to treatment assignment throughout the study. RESULTS: Eighty children (38 in the active-treatment group and 42 in the simulated-treatment group) had outcome data that could be evaluated. There were small increases (7 to 12 liters per minute) in peak expiratory flow in the morning and the evening in both treatment groups, with no significant differences between the groups in the degree of change from base line (morning peak expiratory flow, P=0.49 at two months and P=0.82 at four months). Symptoms of asthma and use of 3-agonists decreased and the quality of life increased in both groups, with no significant differences between the groups. There were no significant changes in spirometric measurements or airway responsiveness. CONCLUSIONS: In children with mild or moderate asthma, the addition of chiropractic spinal manipulation to usual medical care provided no benefit.  相似文献   
967.
Burkholderia strain (JT 1500), able to use 2-naphthoate as the sole source of carbon, was isolated from soil. On the basis of growth characteristics, oxygen uptake experiments, enzyme assays, and detection of intermediates, a degradation pathway of 2-naphthoate is proposed. The features of this pathway are convergent with those for phenanthrene. We propose a pathway for the conversion of 2-naphthoate to 1 mol (each) of pyruvate, succinate, and acetyl coenzyme A and 2 mol of CO2. During growth in the presence of 2-naphthoate, six metabolites were detected by thin-layer chromatography, high-performance liquid chromatography, and spectroscopy. 1-Hydroxy-2-naphthoate accumulated in the culture broth during growth on 2-naphthoate. Also, the formation of 2'-carboxybenzalpyruvate, phthalaldehydate, phthalate, protocatechuate, and beta-carboxy-cis,cis-muconic acid was demonstrated. (1R,2S)-cis-1,2-Dihydro-1,2-dihydroxy-2-naphthoate was thus considered an intermediate between 2-naphthoate and 1-hydroxy-2-naphthoate, but it was not transformed by whole cells or their extracts. We conclude that this diol is not responsible for the formation of 1-hydroxy-2-naphthoate from 2-naphthoate but that one of the other three diastereomers is not eliminated as a potential intermediate for a dehydration reaction.  相似文献   
968.
Smoking is the leading cause of preventable morbidity and mortality in the United States, and the health benefits of quitting smoking are substantial. Nevertheless, over 25% of American adults (48 million individuals) continue to smoke, and the vast majority of quit attempts are unsuccessful. The Agency for Health Care Policy and Research recently addressed the smoking problem by conducting a 2-year research project that was published as the Smoking Cessation Clinical Practice Guideline (Fiore et al., 1996). This article reviews methods, analyses, and results from the Guideline project, and highlights major Guideline recommendations. Guideline findings and recommendations are discussed with respect to their implications for psychology.  相似文献   
969.
OBJECTIVES: To detect in situ the precise osteopontin (OPN) localization in papillary stones. METHODS: Immunocytochemical labelling procedures are applied to detect OPN localizations in crystalline material of renal papillary stones. The tissue-processing procedure for electron microscopy, which includes OsO4 postfixation, preserves both immunocytochemical OPN reactivity and cellular membrane contrast up to the ultrathin section. Reflection-contrast light microscopical images are correlated with high resolution transmission-electron microscopical observations from consecutive ultrathin epon sections. RESULTS: Preserved crystalline material in interstitial and peripheral papillary stones is recognized as calcium oxalate monohydrate. After section incubation with markers conjugated to an antibody against OPN (alpha OPN) the crystals are converted into ghosts. In the ghosts, alpha OPN markers are present around microcrystals. The size of these microcrystals ranges from several nanometers to micrometers. It is observed (due to the OsO4-preserved membranes) that interstitial cells are separated from the stone surfaces by unidentified extracellular material, also present in the center as a stone matrix. CONCLUSION: The microcrystal-growth inhibitor OPN is detected in situ in interstitial stones induced in the rat's papilla and at the surface of the papilla.  相似文献   
970.
BACKGROUND: In coastal Australia, mean house-dust-mite allergen concentration is 20-40 times higher in homes than in public buildings. Allergen concentrations in university colleges, which share some characteristics of both homes and public buildings, are not known. The study aimed to compare bed mite-allergen concentration in colleges with local homes. METHODS: Mattress dust was collected from three colleges (n = 60 in each) and local homes (n = 68) during summer. Der p 1 was measured by ELISA. Information was collected on the floor plan of the colleges, cleaning practices, age of building, and orientation of room. RESULTS: Most college mattresses (94%) had Der p 1 concentrations less than the mean of homes in the same climate. The geometric means of Der p 1 in the mattresses of the colleges were as follows: A, 8.9 micrograms Der p 1/g fine dust (95% CI 6.9, 11.5); B, 1.9 (1.5, 2.3); and C, 1.5 (1.2, 2.0), compared to homes, 22.5 (17.6, 28.7). The percentages of college mattresses with less than 2 micrograms/g were 7%, 48%, and 58%, respectively, compared to 4% for homes. Higher Der p 1 concentrations were weakly associated with age of building in college A, and orientation in college B. Der p 1 concentrations were independent of floor level and age of mattress. CONCLUSIONS: These findings indicate that low allergen concentrations are achievable without extreme hygiene and cleaning measures in a climate which supports mite proliferation in homes.  相似文献   
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