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981.
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
982.
An 8-year longitudinal study of elderly people has provided data concerning age-associated impairment (AAMI). In 1985 a random sample of 146 persons aged 65 years or more, living in their own homes, were assessed using the Guild Memory Test the Mini–Mental State Examination (MMSE) and other ratings. After excluding 21% of the sample because they scored less than 24 on the MMSE, and another 34% who fulfilled other exclusion criteria, some 48% of the remainder (22% of the total sample) clearly fulfilled NIMH criteria for AAMI and a further 36% (16% of the total sample) were recorded as forgetful. The NIMH criteria are appropriate for certain research purposes but not in assessing prevalence of memory disorders. Follow–up interviews were conducted after 2, 4, 6 and 8 years. The mortality rate and development of dementia among those fulfilling criteria for AAMI appeared similar to the other non-demented groups of subjects; the mortality rate of those with MMSE scores below 24 was significantly higher. Guild test results at 2-yearly intervals showed considerable changes; half of those scoring least well who were retested showed improvement. 相似文献
983.
John L. Adams Matthias Schonlau José J. Escarce Meredith Kilgore Michael Schoenbaum Dana P. Goldman 《Health services & outcomes research methodology》2003,4(3):151-167
In order to better inform study design decisions when sampling patients within and across health care providers we develop a simulation-based approach for designing complex multi-stage samples. The approach explores the tradeoff between competing design goals such as precision of estimates, coverage of the target population and cost.We elicit a number of sensible candidate designs, evaluate these designs with respect to multiple sampling goals, investigate their tradeoffs, and identify the design that is the best compromise among all goals. This approach recognizes that, in the practice of sampling, precision of the estimates is not the only important goal, and that there are tradeoffs with coverage and cost that should be explicitly considered. One can easily add other goals. We construct a sample frame with all phase III clinical cancer treatment trials that are conducted by cooperative oncology groups of the National Cancer Institute from October 1, 1998 through December 31, 1999. Simulation results for our study suggest sampling a different number of trials and institutions than initially considered.Simulations of different study designs can uncover efficiency gains both in terms of improved precision of the estimates and in terms of improved coverage of the target population. Simulations enable us to explore the tradeoffs between competing sampling goals and to quantify these efficiency gains. This is true even for complex designs where the stages are not strictly nested in one another. 相似文献
984.
Surgical reinterventions following the Fontan procedure. 总被引:2,自引:0,他引:2
Matus Petko Richard J Myung Gil Wernovsky Mitchell I Cohen Jack Rychik Susan C Nicolson J William Gaynor Thomas L Spray 《European journal of cardio-thoracic surgery》2003,24(2):255-259
OBJECTIVE: The Fontan procedure is utilized as a final reconstructive procedure for patients with functional single ventricle. Short- and long-term outcomes have improved significantly, however, some patients require additional cardiac procedures following the Fontan operation. The outcomes for these reinterventions are not known. METHODS: Cardiac Surgery and Cardiac Intensive Care Unit databases at The Children's Hospital of Philadelphia were reviewed to identify all patients who underwent cardiac surgery after a previous Fontan operation between January 1, 1995 and December 31, 2001. RESULTS: During the study period, 123 procedures were performed in 71 patients. The median time from Fontan to reoperation was 3.6 years (range 0.1-20 years). Indications for reintervention included arrhythmia, cyanosis, 'failing' Fontan circulation or exercise intolerance, protein losing enteropathy, atrioventricular valve (AVV) regurgitation, and other indications. Procedures included pacemaker insertion or revision (n = 59, 48%), reinclusion of previously excluded hepatic veins (n = 16, 13%), revision to either a lateral tunnel or extra-cardiac conduit Fontan (n = 13, 11%), cardiac transplantation (n = 9, 7%), enlargement or creation of a baffle fenestration (n = 6, 5%), isolated AVV repair or replacement (n = 2, 2%), and other procedures (n = 18, 14%). There were five early and five late deaths. Hospital mortality was greatest for patients undergoing cardiac transplantation (4/9, 44%), accounting for 80% of the early deaths. CONCLUSIONS: Surgical reinterventions following the Fontan procedure may be necessary for multiple indications which result in impairment of the Fontan circulation. Most reinterventions can be performed with minimal morbidity and mortality. Survival for patients requiring cardiac transplantation following the Fontan procedure remains poor. 相似文献
985.
The Role of Energy Expenditure in Energy Regulation: Findings from a Decade of Research 总被引:2,自引:0,他引:2
The role of energy expenditure in energy regulation remains a subject of continuing controversy. New data have emerged from studies conducted over the last decade demonstrating that energy expenditure is a critical factor contributing to successful energy regulation in normal individuals, as well as to the disregulation of energy balance that characterizes obesity. Reduced energy expenditure appears to facilitate weight gain in individuals susceptible to obesity and also appears to reduce the extent of body energy loss during undereating in both lean and obese individuals. The magnitude of the reduction in energy expenditure during, and perhaps after, weight loss is greater than expected on the basis of the reduction in body weight and appears to occur in response to undefined underlying determinants of energy regulation. In addition, exercise intervention studies and cross-sectional investigations of the relationship between energy expenditure for physical activity and body composition demonstrate an apparent equilibration between physical activity and body fat content. This equilibration is suggestive of a direct influence of physical activity on the underlying metabolic determinants of energy balance. 相似文献
986.
Prospective assessment of biofeedback for the treatment of paradoxical puborectalis contraction 总被引:25,自引:18,他引:7
Steven D. Wexner M.D. John D. Cheape M.D. Jose M. N. Jorge M.D. Steve Heymen B.A. David G. Jagelman M.D. 《Diseases of the colon and rectum》1992,35(2):145-150
Eighteen patients with chronic constipation were diagnosed as having paradoxical puborectalis contraction (PPC) as the cause for their constipation. The diagnosis of PPC was made after office evaluation, colonic transit study, manometry, cinedefecography, and electromyography (EMG). These 18 patients had a mean duration of symptoms of 26.9 years; none of these patients had unassisted bowel movements. Fourteen patients had a mean of 4.6 laxative-induced bowel evacuations per week, and 11 patients had a mean of 4.4 enema-induced bowel evacuations per week. Patients underwent a mean of 8.9 one-hour EMG-based biofeedback sessions. At a mean follow-up of 9.1 (range, 0.5–12) months, these 18 patients had a mean of 7.3 unassisted bowel actions per week (
P
<0.0001). In addition, persistent laxative use was reported by only two patients, and, in both cases, this was once a week or less (
P
<0.001). Similarly, enema use was reported by only three patients, one once weekly and the other two thrice weekly (
P
<0.002). No biofeedback-related complications were identified. EMG-based biofeedback is a valuable technique associated with an 89 percent success rate in the treatment of PPC.Read at the meeting of The American Society of Colon and Rectal Surgeons, Boston, Massachusetts, May 12 to 17, 1991. 相似文献
987.
In the present studies, arterial lipid metabolism was evaluated in the spontaneously hyperlipidemic obese Zucker rat (fa/fa), the lean Zucker rat (Fa/-), and the Sprague-Dawley (SD) rat. Mean serum cholesterol levels in the obese Zucker, lean Zucker and SD rats were 216 +/- 18 mg/dl, 145 +/- 14 mg/dl and 84 +/- 5 mg/dl, respectively. Arterial cholesterol content was in the same rank order as plasma cholesterol and ranged from a mean of 2.23 +/- 0.10 mg/gm wet wt. in the obese rats to 1.36 +/- 0.04 mg/gm wet wt. in the SD rats. The increased arterial sterol in the obese rats was associated with increased lipid metabolism activity. The in vitro incorporation of [14C]oleate into arterial cholesteryl esters was increased 3-4-fold (P less than 0.01) and incorporation into phospholipids and triglycerides was also elevated (P less than 0.001 and P less than 0.01, respectively). The arterial sterol content and arterial lipid metabolism pattern observed in obese Zucker rat aortas are similar to those found in vessels of other species undergoing atherogenic change. 相似文献
988.
989.
990.
Summary: B-cell development is a highly ordered multistep process dependent upon signals generated by the pre-B and B-cell antigen receptor (BCR). BCR signals drive maturation of the B cell by integrating a number of parallel and sequential biological processes that result in generation of fully immunocompetent B cells. Among these biological processes are positive selection through several developmental checkpoints, negative selection of potentially self-reactive B cells, and activation of the mature B cell. In addition, recent studies have shown that developing and mature B cells rely on the constant activity of the BCR for their continued survival. Ligand (antigen)-dependent and -independent mechanisms of BCR signaling have been proposed, but their specific contributions to B-cell maturation and differentiation in the bone marrow and periphery are not completely clear. We discuss here a model, whereby ligand-independent basal BCR activity would be sufficient to trigger B-cell development through to the mature stage. However, long-term survival and formation of specific mature B-cell populations may be dependent on ligand–receptor interactions. 相似文献