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51.
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   
52.
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   
53.
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   
54.
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   
55.
K L Reuter  T Griffin  R E Hunter 《Cancer》1989,63(6):1123-1128
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   
56.
Timing of carotid endarterectomy after acute stroke   总被引:2,自引:0,他引:2  
An arbitrary delay of at least 6 weeks before performing carotid endarterectomy after acute stroke has been recommended based on anecdotal reports. This prolonged interval may increase the danger of recurrent neurologic deficit before surgery. From September 1978 to September 1988, carotid endarterectomy was performed on 140 patients at variable intervals after stroke. Eleven patients had temporary stroke, which left 129 patients with neurologic symptoms that persisted for 3 weeks or had a cortical infarct on CT scanning. A prospective therapeutic protocol was applied to 82 patients admitted with acute stroke. They were observed until neurologic recovery reached a plateau, based on clinical observation by a neurologist, before performing angiography and carotid endarterectomy (group I). Forty-seven patients were not seen until after recovery from stroke was established (group II). At initial presentation, the severity of neurologic deficit was classified as mild, moderate, or severe in 31%, 58%, and 11%, respectively. Recovery before operation was registered as complete in 11%, mild residual in 66%, moderate residual in 21%, and severe residual in 2%. Group I patients (n = 82, 64%) were operated on within 6 weeks of stroke and group II (n = 47, 36%) were operated on at varying times after 6 weeks. No significant difference was found in the incidence of cerebrovascular events (1.2% vs 4.2%) and deaths (1.3% vs 2.1%) between groups I and II with respect to the timing of carotid endarterectomy, and no significant difference was found between patients operated on at 2, 4, 6, or more than 6 weeks after stroke.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
57.
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   
58.
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   
59.
60.
Laparoscopic Nissen fundoplication (LNF) has become the most commonly performed antireflux procedure since its introduction in 1991. There are few studies with greater than 5-year outcomes. Herein we report a series of 312 consecutive patients who underwent primary LNF before 1996. Follow-up of more than 6 years was available in 166 patients, and the mean follow-up was 11 years (median 11.1 years, range 6.1–13.3 years). Prospective data collection included preoperative and current symptom scores (scale 0 = none to 3 = severe), as well as the level of patient satisfaction and use of antireflux medications. Total symptom score for each patient was summed from seven symptoms for a maximum value of 21. Heartburn and regurgitation were the most improved symptoms; however, all symptoms were significantly improved (P < 0.01). The total symptom score at follow-up was 2.6 down from 7.5 at baseline, with a mean difference of −4.9 (range −12 to 3). The percentage of patients stating they would have the procedure again was 93.3%, and 70% were off daily antireflux medications. Outcomes at a mean of 11 years after LNF are excellent, and the majority of patients had their symptoms resolved or significantly improved and are satisfied with their results. Presented at the 47th Annual Meeting of the Society for Surgery of the Alimentary Tract, May 22, 2006, Los Angeles, CA  相似文献   
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