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991.
The Child and Adolescent Trial for Cardiovascular Health (CATCH) is a multisite intervention research study that builds on significant progress made in school health education research in the 1980s. The study has three phases: Phase I deals with study design, intervention, and measurement development, Phase II involves the main trial in 96 schools in four states, and Phase III focuses on analysis. The intervention program targets third-fifth grade students and focuses on multiple cardiovascular health behaviors, including eating habits, physical activity, and cigarette smoking. Classroom curricula, school environmental change, and family involvement programs are developed for each grade level and behavioral focus. This paper describes Phase II of CATCH with a rationale for cardiovascular health promotion with youth. The process of change that appears to be necessary for school-based health promotion and that will be tested in CATCH are presented as a framework to guide these efforts.  相似文献   
992.
Epicardial antiarrhythmic drug administration was studied as a therapeutic approach for experimental ventricular tachycardia (VT) in an open-chest dog model. Lidocaine-polyurethane matrices (28%, w/w) were formulated as a model system. Matrices were placed on the left ventricular epicardium in each of 23 anesthetized open-chest dogs with ouabain-induced VT, to evaluate effectiveness in restoring sinus rhythm. Conversion occurred in all animals treated with matrices containing 300 mg or more of lidocaine after 1.5 to 7.0 min. The matrix lidocaine content correlated linearly with the time required for conversion to sinus rhythm (r = 0.75, P = 0.0002); irrespective of matrix size the myocardial/plasma lidocaine ratio was 20.1 ± 4.2 (mean ± SD) at the time of conversion. In a separate series of five dogs without ventricular tachycardia, systolic wall thickening measured with sonomicrometers after 5 min of controlled-release lidocaine administration (500- to 1000-mg matrix lidocaine content, 7.48 ± 3.49-mg/kg dose) was only minimally diminished (–14.1%) and this effect was observed only at the site of matrix placement on the anterior-apical epicardium. In contrast, intracoronary injection of 0.3 or 1.0 mg/kg of lidocaine-HCl resulted in complete elimination of wall thickening or replacement by systolic thinning. Thus epicardial administration of lidocaine from polyurethane matrices was an effective means of treating ouabain-induced ventricular tachycardia. Regional myocardial function in the vicinity of the matrices was modified to a very limited degree, supporting the view that the matrices can be used safely, without serious risk to ventricular contractile performance.  相似文献   
993.
Conclusion Reviewing the history of diagnostic procedures of causative organisms of respiratory infections, invasive techniques such as the protected specimen catheter (PSB) and bronchoalveolar lavage (BAL) have become the preferred choices because they have many advantages. These methods cause the patient relatively little discomfort, and permit an early diagnosis since they can easily be performed at the bedside and the causative organism from the disease site is obtained in cultures. These procedures can be used not only in patients with community-acquired lung infections, but also in immunocompromised hosts, including those with blood diseases or following renal transplantation, in patients in intensive care units and in mechanically-ventilated patients so that the cause can be accurately determined and chemotherapy started quickly, resulting in better therapeutic efficacy. Although these invasive procedures are advantageous for the diagnosis of respiratory infections, they also present various problems which remain to be addressed including minimizing contamination and setting diagnostic threshold values. However, the importance of accurately determining the causative organism in respiratory infections should be recognized as the most important factor, and these methods have shown to date to provide the most accurate information to aid in the timely treatment of respiratory infections in a wide variety of patients.  相似文献   
994.
Sutton's Law     
  相似文献   
995.
Congenital endophthalmitis following maternal shellfish ingestion   总被引:1,自引:0,他引:1  
Purpose: To highlight an unusual organism causing a unilateral endophthalmitis by transplacental spread.
Method: We report a case of Plesiomonas shigelloides endophthalmitis, presenting in a newborn, with co-existing septicaemia and meningitis. There was a significant maternal history of diarrhoea associated with the ingestion of oysters 2 weeks prior to delivery.
Result: The endophthalmitis was treated with parenteral antibiotics and topical mydriatics with complete resolution, although subsequent assessment of the affected eye suggests a poor visual outcome.
Conclusion: Endophthalmitis in the newborn is an unusual clinical finding and usually presents with other manifestations of bacteraemia. Plesiomonas shigelloides is fortunately an infrequent cause of neonatal infection, but is associated with a high degree of morbidity and mortality. We postulate that this neonate acquired P. shigelloides via the transplacental route, and suggest that this organism be included in the list of 'other' causes of transplacental infection that has been abbreviated to 'O' in the acronym TORCH.  相似文献   
996.
The epoxyalkanoyl derivatives were designed and synthesized as ACE inhibitors. Coupling of unsaturated carboxylic acids with amino acids and following epoxidation with dimethyldioxirane gave the epoxyalkanoyls with high yield. The inhibitory activity of synthesized compounds on angiotensin converting enzyme was IC50 values of 0.06≈5.5 μM.  相似文献   
997.
998.
Background: Myocardial protection during open heart surgery is based on administration of oxygenated blood cardioplegia, the preferred temperature of which is still under debate. The current randomized study was designed to prospectively evaluate the quality of myocardial protection and the functional recovery of the heart with either normothermic (group N) or hypothermic (group H) oxygenated blood cardioplegia.

Methods: Under continuous electrocardiographic Holter monitoring, 42 patients were randomly scheduled to receive either normothermic (33.5 degrees C) or hypothermic (10 degrees C) cardioplegia solutions during coronary bypass grafting surgery. Blood samples for creatinine phosphokinase, creatinine phosphokinase-MB, lactate, epinephrine, and norepinephrine were withdrawn during cardiopulmonary bypass via a coronary sinus cannula.

Results: Active cooling in group H on initiation of cardio-pulmonary bypass was characterized by transition through ventricular fibrillation in 75% of patients, whereas in group N atrial fibrillation occurred in 65% of patients. On myocardial reperfusion, sinus rhythm spontaneously resumed in 95% of group N patients compared to 25% in group H (P = 0.0003). In the latter, 75% of patients developed ventricular fibrillation often followed by complete atrioventricular block, which necessitated temporary pacing for a mean duration of 168+/-32 min. Both groups showed a similar incidence of intraventricular block and ST segment changes. However, the incidence of ventricular premature beats in the first 16 h after cardiopulmonary bypass was significantly greater in group H (P < 0.05), 20 +/-26/h, compared to 3+/-5/h in group N. Blood concentrations of lactate, creatinine phosphokinase, epinephrine, and norepinephrine increased gradually during the operation, but the differences between the groups were not significant.  相似文献   

999.
1000.
HBV-M定量检测与HBV-DNA含量水平关系的初步探讨   总被引:2,自引:0,他引:2  
目的 研究乙型肝炎病毒标志物定量检测结果与其HBV-DNA含量的临床关系。方法 采用时间分辨免疫定量和荧光定量-PCR技术,对HBV-DNA和HBV-DNA含量进行检测。结果 在HBsAg/HBeAg/HBcAb,HBsAg/HBcAb/HBcAb,HBeAg/IC及单纯HBcAb阳性的四个组别中,HBV-DNA阳性率分别是97.17%、30.56%、100%和25%;在HBsAg,HBeAg,HBeAb,HBcAb定量检测高,低值两组HBV-DNA含量对比中,HBV-DNA阳性率分别为76.92%、58.14%;100%、97.26%;20.00%、11.42%;64.62%、27.63%。结论 HBV-DNV比HBV-M更能及时准确反映乙型肝炎病毒感染者的病程情况。  相似文献   
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