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101.
Objective To compare changes in total and regional body composition using dual energy X-ray absorptiometry (DEXA) after subjects lost weight through change in diet or exercise.Design A 12-month, randomized, controlled study of two weight-loss interventions — low-fat diet ad libitum or moderate, unsupervised exercise — in free-living, middle-aged men. Compliance was determined at monthly measurement sessions through food records and activity logs; DEXA scans were performed every 3 months.Subjects/setting Fifty-eight overweight men (mean body mass INDEX=29.0±2.6; mean AGE=43.4±5.7 years) recruited from a national corporation were assigned randomly to diet, exercise, or control groups.Interventions One group reduced dietary fat to 26.4% of energy intake but kept activity unchanged; another group self-selected aerobic exercise (three sessions per week at 65% to 75% maximum heart rate) but kept diet unchanged. A control group maintained weight.Main outcome measures At 12 months, measurements of weight, total and regional fat mass and lean mass, energy intake, and percentage dietary fat; physical activity indexes. Statistical analyses Results were analyzed using paired t tests and analysis of variance.Results Mean weight loss was 6.4±3.3 kg in dieters and 2.6+3.0 kg in exercisers; control subjects maintained weight. DEXA scans revealed that 40% of dieters’ weight loss was lean tissue; more than 80% of weight lost by exercisers was fat. Exercisers maintained limb lean tissue and lost fat mass.Conclusions Greater total weight and lean tissue loss occurred when subjects lost weight through a low-fat diet consumed ad libitum than when subjects participated in unsupervised aerobic exercise. Use of DEXA enabled identification of progressive total and regional changes in fat and lean tissue. J Am Diet Assoc. 1997; 97:37–42.  相似文献   
102.
A study to explore the role of a community oncology nurse specialist   总被引:1,自引:0,他引:1  
Cancer patients are increasingly being cared for in the community. However, the role of the community oncology nurse specialist (CONS) remains a rare appointment in the United Kingdom. There is little research evidence to substantiate the view that this is a worthwhile and effective role. This study aimed to explore the role of one CONS using a qualitative case study approach. The sample consisted of the CONS, seven patients, no relatives and five community nurses. Semi-structured interviews were used to elicit the view of these participants. In addition, documents containing details of the CONS's work to date were reviewed. A number of the CONS's role components were identified by the different respondent groups. Five themes were identified within the data collected: functions of the CONS, communication between the CONS and other health care professionals, structural and organizational factors, characteristics of the service and benefits to patients and their families. Furthermore, all respondent groups were positive about the service offered by the CONS, and felt that the role was valuable. Some negative features were identified and these were concerned with organizational aspects of the service. The findings suggest the need for further research and evaluation in this area.  相似文献   
103.
C. R. Goucke  MB  ChB  FFARACS    J. P. Keaveny  MB  BCh  BAO  FFARCS  B Kay  DMSc  MB  ChB  FFARCS  T. E. J. Healy  MSc  MD  FFARCS  M. Ryan  MB  ChB  FFARCS 《Anaesthesia》1990,45(4):329-331
Eighty-two outpatients who received general anaesthesia for surgical removal of maxillary or mandibular third molars were given either diclofenac 75 mg or nefopam 20 mg intramuscularly for postoperative pain control. They and the control group were also allowed oral paracetamol as required. The results showed that there was no significant pain relief from these single intramuscular injections.  相似文献   
104.
1. Left ventricular (LV) hypertrophy has been implicated in the reduction of baroreflex sensitivity present in hypertension. The aim of the current study was to investigate the mean arterial pressure-heart rate reflex (MAP-HR) in a model which induced left ventricular hypertrophy but no sustained blood pressure elevation. 2. Five mongrel dogs were exposed to transient blood pressure elevation of between 20 and 30 mmHg, through hindlimb compression using a pneumatic pressure suit, for 7 h per day, 6 days per week for 6 weeks. Resting blood pressure was not altered by the 6 week hindlimb compression intervention. 3. Echocardiographically determined LV mass (mean ± s.e.m.) was 116.0 ± 7.4 g prior to hindlimb compression (baseline) and elevated to 125.4 ± 8.1 g (P= 0.003) after 6 weeks of compression. A reduction in the early (E) to late (A) transmitral diastolic flow ratio (E/A) from 1.80 ± 0.06 at baseline to 1.54 ± 0.09 (P = 0.037) after the 6 week intervention suggested that cardiac compliance was reduced. 4. The maximum gain of the MAP-HR reflex, studied using the ‘steady-state’ drug technique, when blood pressure was normal, showed a trend for reduction from 3.85 ± 0.43 beats/min per mmHg at baseline to 3.10 ± 0.45 beats/min per mmHg (P= 0.067) after 6 weeks of compression. This gain reduction became significant after β-adrenoceptor blockade with propranolol (3.13 ± 0.55 vs 2.32 ± 0.25 beats/min per mmHg; P= 0.039). Covariant analysis showed a significant inverse correlation between LV mass and maximum gain (r= 0.96; P<0.001) during the 6 week compression period. 5. The MAP-HR reflex changes in this model mimic those present in hypertension and implicate cardiac hypertrophy as one possible mediator.  相似文献   
105.
From January 1986 to December 1991 we examined the eyes of 206 infants born at Westmead Hospital, Neonatal Intensive Care Unit who were less than 29 weeks' gestation at birth to determine the incidence of retinopathy of prematurity. Eighty-five infants (41.3%) had no retinopathy of prematurity (ROP) in either eye, 82 infants had stages 1 or 2 ROP (39.8%), 29 had stage 3 ROP (14.1%) and 11 had stage 4 ROP (5.3%). Of these, cryotherapy was performed in 18; six now have bilateral retinal detachment and are blind The more severe stages of ROP were significantly associated with an increase in the number of days of oxygen supplementation, an increase in the number of days of mechanical ventilation and the presence of patent ductus arteriosus. Infants receiving steroids for mechanical ventilator dependence had a significantly greater chance of requiring cryotherapy (11 or 22 receiving steroids versus seven of 43 without steroids; P < 0.01).  相似文献   
106.
The concept of need and the practice of needs assessment are both subject to a wide range of interpretations, to the likely detriment of individual assessments and to multidisciplinary working. Clear definition is important for individual assessment, for the development of multidisciplinary tools and in gathering planning information. The concept of need is clarified, firstly by distinguishing between need and the difficulties that engender it, and secondly through a taxonomy of need. These assist clear definitions of both need and needs assessment when linked with a consideration of the current help a person receives and a specification of the type of help required by a person to meet their needs. Such definitions have implications for the role of needs assessment in individual assessment, service evaluation, service management and planning and in the development of multidisciplinary needs assessment tools.  相似文献   
107.
Study Objective . To determine the efficacy of high-dose ascorbate supplementation in lowering lipoprotein(a) [Lp(a)] levels in patients with premature coronary heart disease (CHD). Design . Randomized, double-blind, placebo-controlled trial. Setting . Outpatient clinic. Patients . Forty-four patients with documented premature CHD. defined as confirmed myocardial infarction and/or angiographically determined stenosis of 50% or greater in at least one major coronary artery before age 60 years. Interventions . Patients were block randomized on the basis of age, gender, and screening Lp(a) concentrations to receive ascorbate 4.5 g/day or placebo for 12 weeks. Measurements and Main Results . High-dose ascorbate was well tolerated and produced a marked elevation in mean plasma ascorbate levels (+1.2 mg/dl; p<0.001). Multiple linear regression analysis revealed no significant effect of supplementation on postintervention Lp(a) levels (p=0.39) in a model that included treatment group assignment, and baseline Lp(a) levels. Conclusions . Our findings do not support a clinically important lowering effect of high-dose ascorbate on plasma Lp(a) in patients with premature CHD.  相似文献   
108.
Effect of Glycemic Carbohydrates on Short-term Satiety and Food Intake   总被引:3,自引:0,他引:3  
We examine the relationships between glycemic carbohydrate and its effects on short-term satiety and food intake. Both high- and low-glycemic carbohydrates have an impact on satiety, but their effects have different time courses. High-glycemic carbohydrates are associated with a reduction in appetite and food intake in the short term (e.g., one hour), whereas the satiating effects of lower-glycemic carbohydrates appear to be delayed (e.g., 2 to 3 hours). There is no consistent evidence that an increase in blood glucose, either acute or sustained, is the primary determinant of their effects on food intake and satiety. Many other preabsorptive and postabsorptive signals for satiety exist and may be the determining factors. Further studies are needed to delineate the role of glycemic carbohydrates and their mechanisms of action in determining satiety.  相似文献   
109.
110.
This paper, written by two male nurse teachers, describes and analyses their experience of working in a nurse education culture permeated by the philosophy of business management The introduction of business management practices to nurse education is discussed as a reflection of the current political hegemony of market forces and individualism The authors discuss the implications for nurse teachers of being continually exposed to these politically motivated forces which increasingly provide the paradigm for service developments within the United Kingdom health services In discussing the impact of this exposure it is argued that at the personal level individual teachers are experiencing a degree of apathy and personal dissonance which undermines their professional value system, resulting in emotional distress and a crisis of identity It provides a critical reflection on the way organizational dynamics and power relations influence the subjective sense-making of individuals The authors use a multiplicity of perspectives, including those provided by individual psychology, power relations, feminism and personhood, to argue for the need to develop an alternative paradigm which is characterized by the valuing of individual persons, empathic sensitivity and the fostering of creativity been important to us from a personal and professional  相似文献   
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