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51.
R W Pinner B G Gellin W F Bibb C N Baker R Weaver S B Hunter S H Waterman L F Mocca C E Frasch C V Broome 《The Journal of infectious diseases》1991,164(2):368-374
Active surveillance for invasive meningococcal disease was conducted during 1986 and 1987 in six areas of the United States with a total population of approximately 34 million persons. The incidence of meningococcal disease was 1.3:10(5). The highest incidence of disease among the surveillance areas was in Los Angeles County (1.65:10(5). Neisseria meningitidis serogroups B and C caused about equal amounts of disease, which reflects a recent increase in the incidence of group C disease. Group C caused more than half of the cases of meningococcal disease in Los Angeles and Tennessee but less than one-third of the cases in Missouri and Oklahoma. Multilocus enzyme electrophoresis demonstrated that a group of closely related isolates of N. meningitidis was prevalent in Los Angeles during the surveillance period and was associated with an increased incidence of meningococcal disease there. 相似文献
52.
Amaya Gillespie Warren Stanton John B. Lowe Beth Hunter 《The Journal of school health》1995,65(10):432-437
ABSTRACT: This study obtained input from Australian student smokers approximately 15 years old, which may be useful in designing school-based smoking cessation programs. The sample was analyzed by previous quitting experience and intentions to quit. The order of preference for assistance options and incentives for quitting was similar across all groups: however, those who previously attempted to quit (previous quitters) and those who intended to quit (intenders) in the future were significantly more likely than non-quitters and non-intenders to find assistance options for quitting acceptable. The potential for saving money emerged as an important variable in convincing all groups of smokers not to smoke, and using personal willpower and cutting down slowly were identified as important in actual attempts to quit. The need for programs to be free and for friends to be supportive also was evident across all groups. 相似文献
53.
Myocardial oxygen consumption (MVO2) includes components for 1) mechanical energy generation, 2) activation, and 3) basal metabolism. Whereas the first two components are expected to increase in proportion with heart rate, a significant basal level of metabolism would consume oxygen even if the heart rate were zero. Contrary to this expectation, however, a previous study reported that, during unloaded beats, MVO2 per beat (which includes basal metabolism) was independent of heart rate. Accordingly, unloaded MVO2 per minute would extrapolate to zero at zero heart rate; this result is unexpected considering basal metabolism. To resolve this inconsistency, we varied heart rate over a wide range after inducing atrioventricular block in eight isolated cross-circulated canine hearts that contracted isovolumically. We examined whether a term representing rate-independent basal metabolism was needed to describe MVO2 per minute. Mechanical energy generated by the left ventricle was evaluated from the pressure-volume area, which was altered by changing isovolumic ventricular volume over at least five levels at each heart rate. Contractility, evaluated by the slope of the end-systolic pressure-volume relation, did not vary significantly with heart rate in this study. In contrast to the previous report, unloaded MVO2 per beat (i.e., MVO2 extrapolated to a pressure-volume area of zero) was not constant but fell monotonically with increases in heart rate in every heart. We considered that this trend was caused by a significant rate-independent basal level of MVO2 per minute. Multiple linear regression analysis confirmed that this rate-independent basal term differed significantly from zero in seven of the eight hearts studied.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
54.
The effects of acetazolamide, calcitonin (CT), and parathyroid hormone (PTH) on acid production in isolated osteoclasts has been investigated. Osteoclasts were isolated from the endosteum of 3-week chick tibias and were maintained under culture conditions for 5 days. The cells were treated with acetazolamide (10 x 4 M and 10(-7) M), CT (1 mU/ml and 0.31 mU/ml) and PTH (6.5 U/ml and 0.40 U/ml) for 1, 3, 6, and 18 hr. The cells were stained with acridine orange and the intensity of fluorescence measured by a light microscope photometer. Acetazolamide treatment resulted in a steady decline in intracellular acidity, suggesting that carbonic anhydrase plays a major role in acid production in isolated osteoclasts. Treatment with PTH produced a decline in acidity at 1 hr, followed by a peak at 3 hr and then a decline at 6 and 18 hr. The transient increase in acidity may be due to activation of carbonic anhydrase by PTH. Calcitonin treatment also resulted in a decline in cell acidity which was similar, but less pronounced than that resulting from acetazolamide treatment. These results indicate that calcitonin may mediate osteoclast activity by alterations in intracellular acid production. 相似文献
55.
J G Hunter 《The Surgical clinics of North America》1992,72(3):655-664
Gynecologists have found the argon and CO2 lasers very valuable for performance of pelviscopic surgery. Their interest was born from the complications initially seen with electrosurgical pelviscopic procedures and from the unique features of the laser for treatment of endometriosis. Laser technology was applied to laparoscopic cholecystectomy from its inception. This article reviews the arguments for laser and electrosurgical use in the many laparoscopic procedures--established and in evolution. 相似文献
56.
Comparison of abdominopelvic computed tomography results and findings at second-look laparotomy in ovarian carcinoma patients 总被引:1,自引:0,他引:1
In 35 women with epithelial carcinoma of the ovary, the results of restaging laparotomy were compared with the preoperative abdominopelvic computed tomography (CT) findings to evaluate the accuracy of CT for determining tumor status. In the 36 studies performed, enhanced CT scans at 10-mm to 15-mm intervals had a sensitivity of 84% and a specificity of 88%; in addition, there was 86% agreement between the CT and surgical findings. These results suggest that although CT is not accurate enough to completely replace the restaging laparotomy, its high accuracy in determining residual disease after treatment is helpful for patient management. 相似文献
57.
58.
R L Weinsier L D James B E Darnell N H Wooldridge R Birch G R Hunter A A Bartolucci 《The American journal of clinical nutrition》1992,56(1):44-49
The separate effects of energy restriction and weight loss on serum lipids were studied in 24 postmenopausal moderately obese women before and after weight loss of greater than 10 kg to normal weight. Fasting serum triglycerides (TGs), total cholesterol (TC), high-density-lipoprotein (HDL) and low-density-lipoprotein (LDL) cholesterol, and insulin were measured at the end of four 10-d in-hospital phases, two before and two after weight loss: phase I, stable weight; phase II, 3350 kJ/d(800 kcal/d), followed by outpatient weight loss; phase III, 3350 kJ/d (800 kcal/d); and phase IV, stable weight. Diet composition and exercise were constant the entire study. Energy-restriction effect was determined by comparing average values in stable-weight phases (I and IV) with low-energy phases (II and III); weight-loss effect was determined by comparing values in obese phases (I and II) with reduced-weight phases (III and IV). Energy restriction lowered TG, TC, LDL cholesterol, the LDL-HDL cholesterol ratio, and insulin and raised HDL cholesterol (all P less than 0.05). Weight loss lowered TG, TC, LDL cholesterol, and insulin (all P less than 0.01) but did not change HDL cholesterol or the LDL-HDL cholesterol ratio. The results suggest that reduction to a weight-steady nonobese state significantly lowers TG, TC, and LDL cholesterol but does not improve HDL cholesterol or the LDL-HDL cholesterol ratio. 相似文献
59.
OBJECTIVES: The Women's Health Questionnaire (WHQ) includes 36 items assessing nine domains of physical and emotional experiences of mid-aged women. The primary aim of the current research was to examine the psychometric properties of the WHQ across linguistic versions in view of the increased need for reliable health-related quality of life (HRQL) measures in multinational studies. METHODS: In this paper, we examine the hypothesized structure of the questionnaire in a UK sample, to develop and verify a revised model to be used in multicenter, international studies. RESULTS AND CONCLUSIONS: Content analysis and evaluation of missing data led to exclusion of 'Menstrual symptoms' and 'Sexual behavior' domains, retaining these as optional modules of the core questionnaire. Additionally, item 13 was excluded because it does not investigate the same concepts as other domains and the deletion of five additional items appeared to improve the questionnaire's factor structure. The revised WHQ comprises 23 items, investigating six domains. The cross-sectional psychometric properties of the 23-item WHQ were good and better than those of the 36-item version. The 23-item WHQ was assessed with multinational data, to evaluate cross-cultural equivalence of linguistically adapted versions. In addition, its reproducibility and responsiveness need to be documented. 相似文献
60.