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961.
We describe a case of Staphylococcus lugdunensis pulmonary valve endocarditis in a 65-year-old woman on chronic hemodialysis and provide a review of previously reported cases. The patient presented with fever and altered mental status, but had no other localizing symptoms or signs; coagulase-negative staphylococcus (subsequently identified as S. lugdunensis) was isolated from two sets of blood cultures. Transthoracic and transesophageal echocardiograms showed a large (2.3 x 3.1 cm) vegetation on the pulmonary valve with moderate valvular insufficiency. The patient was treated with 6 weeks of antibiotic therapy and is stable 4 months following the completion of therapy; no surgical intervention was performed. Of the 28 previously reported cases of S. lugdunensis endocarditis, only 1 had previously survived with medical therapy alone. This is the 3rd case report of S. lugdunensis endocarditis in a patient on hemodialysis; the presumed portal of entry in this and previously reported cases was the vascular access device. Endocarditis due to this organism is characterized by a high mortality, rapid tissue destruction, and a predilection for native valves. Because the clinical outcome is much more favorable with valvular replacement, speciation of the organism assumes great importance in defining the therapeutic approach. Copyright Copyright 1999 S. Karger AG, Basel 相似文献
962.
BACKGROUND: Action research has been used successfully to promote change in disciplines other than medicine, but there are few examples of its use in primary care. OBJECTIVE: We aimed to discuss the benefits and difficulties of using action research in primary care using the example of child health surveillance provision in general practice. METHODS: Twenty-eight general practices were randomly allocated into two groups. Action research was used to promote change in 14 practices by facilitating practice meetings and by providing written feedback. The other 14 practices received written feedback alone. The two groups of practices were compared using the following: (i) semi-structured interviews with one health visitor and GP from each practice; (ii) observation of baby clinics; (iii) questionnaires to parents; and (iv) return rates of child health surveillance reviews from the personal child health record. RESULTS: All 14 practices in the action research arm of the study met as individual practice teams and decided to make changes to their provision of child health surveillance. Ten practices audited their child health surveillance as a result. More health visitors in the action research practices than in the comparison practices reported changes to child health surveillance, audit, communication and use of the personal child health record. The majority of health visitors and GPs thought involvement in the action research process was beneficial. However, we were unable to show a statistically significant difference between the two groups of practices in baby clinic provision, parent satisfaction or the return rate of child health surveillance reviews. CONCLUSION: Our study suggests that action research is a successful method of promoting change in primary care. However, measuring the impact of change is difficult. 相似文献
963.
BACKGROUND: Recent guidelines for those with acute low back pain have advocated early resumption of normal activity and increased physical activity. Little is known about the relationship between low back pain and physical activity, and on the impact of that relationship on the promotion of increased levels of physical activity within a general practice population. OBJECTIVES: We aimed to explore associations between factors that influence changes in physical activity and the way individuals perceive and behave with their low back pain, and the impact of those perceptions and behaviour on physical activity. METHODS: Twenty-seven informants were chosen using a purposive sample from a larger group of individuals who, because of their low back trouble, had been referred by their GPs to a community-based, single-blind, randomized controlled trial (RCT) at the University of York, which is evaluating the effectiveness and cost-effectiveness of a progressive exercise programme. Fifty-four interviews were conducted with this subgroup of the RCT; four informants were interviewed once, 19 twice and four of them three times. Interviews were transcribed and analysed using manual and computer-aided approaches. RESULTS: Physical activity was perceived as (i) activities of daily living, (ii) activities causing breathlessness that they went out of the way to do and (iii) more competitive-type activity. The avoidance of physical activity and fear of pain returning were the two main factors directly associated with informants' backs and changes in physical activity. These two factors hindered increases in physical activity, even though the majority of informants believed strongly that being physically active helped ease their low back pain. CONCLUSIONS: When advocating that individuals with acute low back pain return to or increase physical activity, it is important that clinicians identify avoidance of physical activity and/or fear of pain at the earliest stage in order to tailor advice and reassurance appropriately. If avoidance of activity and fear of pain is identified and clinicians want to encourage patients to take up and sustain increased physical activity, they should explore issues of fear of pain, and avoidance of and confidence to do physical activities, in addition to other factors influencing physical activity. 相似文献
964.
Whole cell and five different types of acellular pertussis vaccine were assayed using a mouse aerosol challenge model which permitted delivery of a controlled, consistent dose of Bordetella pertussis to the lower respiratory tract. Using this system, the viable counts in the lungs of vaccinated mice were immunisation dose-dependent and allowed the protective capacity of different vaccine preparations to be distinguished. This model may thus provide the basis for a protection assay for pertussis vaccines. Comparison of acellular vaccines with a whole cell pertussis vaccine showed that the latter gave better active protection in mice but with a different dose-response relationship. Thus the two types of vaccine are not directly comparable in the same assay and require different reference standards. A pentavalent type acellular vaccine is suggested as a possible candidate standard for the acellular vaccine potency test. The results suggest that this aerosol challenge model has potential for use as a potency test for acellular pertussis vaccines. 相似文献
965.
Savitz Dole Williams Thorp McDonald Carter & Eucker 《Paediatric and perinatal epidemiology》1999,13(1):114-125
We describe the study design and patterns of participation for a cohort study of preterm delivery, focused on genital tract infections, nutrition, tobacco use, illicit drugs and psychosocial stress. Women are recruited at 24–29 weeks' gestation from prenatal clinics at a teaching hospital and a county health department. We recruited 57% of the first 1843 eligible women; 29% refused and 8% could not be contacted. White women were somewhat more likely to participate than African-American women (61% vs. 54% respectively). More notable differences were found comparing teaching hospital and health department clinics (71% vs. 47% participation respectively), with the health department clinic having a greater proportion refuse (24% vs. 33%) and more women who could not be contacted (4% vs. 11%). Participation was affected only minimally by day or timing of recruitment, but inability to contact diminished substantially as the study continued (13–0%). Refusals were largely unrelated to patient attributes. Lower education predicted inability to contact. Risk of preterm delivery was 14% among recruited women, 10% among women who refused, and 15% among women whom we were not able to contact, demonstrating that, overall, risk status was not lower among recruited women. 相似文献
966.
OBJECTIVES: To examine the rape attitudes of a sample of 252 British medical students. DESIGN: A 20-item questionnaire was used. SETTING: A London medical school. SUBJECTS: Fourth-year medical students. RESULTS: In general, students were well informed on legal and factual issues regarding rape and sexual assault. However, significant differences were found in the attitudes to rape between males and females. Female students were significantly more positive in their responses to victims. CONCLUSIONS: These results support findings from previous studies of rape attitudes in other professional groups. Better knowledge and enlightened attitudes amongst health care staff can have a significant impact on the management of sexual assault and influence the likelihood of victims presenting for treatment. In conclusion, this study emphasizes the importance of teaching about sexual violence in British medical schools. 相似文献
967.
Cockerill R Tanner J Barnsley J Williams AP 《The Journal of health administration education》1999,17(3):199-210
This paper examines the backgrounds, behaviours, and attitudes of a representative sample of male and female pharmacy managers in Ontario, Canada. It shows that the female managers are younger than their male colleagues, and spend significantly more time on childcare activities. There were no differences between the male and female managers in terms of work commitment and job responsibilities, but the female managers spent more time in direct patient contact, an activity that the qualitative analysis indicated was important to them. Female managers were also more supportive of strategies that would encourage additional patient counseling. For faculty in health administration programs, the results suggest that the importance that females place on the psycho-social aspects of their jobs as managers needs to be recognized and supported in the development and delivery of courses of study. 相似文献
968.
The effects of several corrections for ascertainment bias on a linkage result in the COGA data are examined. A correction that models the complete ascertainment protocol markedly reduces the evidence for linkage. Different partial corrections increase the linkage signal and recover good estimates of the population trait prevalence, but do not represent adequately the complexity of the COGA ascertainment scheme. Evidently the present size of the COGA data set cannot support a complete correction for ascertainment bias, but an effective partial correction can and should be implemented. 相似文献
969.
970.
J T Snook S Park G Williams N Tsai Y-HLee 《European journal of clinical nutrition》1999,53(8):597-605
OBJECTIVES: To determine relative effects of diets high in synthetic sources of myristic (14:0), palmitic (16:0) or stearic (18:0) acid on concentrations and metabolism of serum lipoproteins. DESIGN: Eighteen healthy women participated in a three-way cross-over study for five week periods separated by seven week washout periods, diets were assigned in random order. SUBJECTS: Premenopausal women, not on medication, were from three races (Caucasian, African-American, Asian) and four apolipoprotein E phenotype groups (3/3, 3/2, 4/3, and 4/2). INTERVENTION: During the first week the subjects consumed a baseline diet providing 11 energy (en)% saturated fat, 10en% polyunsaturated fat and 14en% monounsaturated fat. Followed by test diets with 19en% saturated fat (including 14en% test saturated fatty acid), 3en% polyunsaturated fat, and 14en% monounsaturated fat for four weeks. Synthetic fats (trimyristin, tripalmitin, and tristearin) were used in blends with natural fats and oils. RESULTS: Mean concentrations of serum total, esterified and LDL cholesterol were significantly lower after 18:0 than after 16:0 (n = 16-18, P < 0.01 for treatment effect). Myristic acid (14:0) had an intermediate effect. Receptor-mediated degradation of 125I-LDL in mononuclear cells obtained from the subjects was lower after 16:0 than after 14:0 and 18:0 (n = 16-18, P=0.05 for treatment effect). Differences in the digestibilities of the fats were not a major factor in the results. Strong cholesterolemic responses to the 16:0 diet were partly explained by apoE phenotype. CONCLUSIONS: As noted previously, stearic acid was neutral compared to 14:0 and 16:0. In contrast to studies involving natural fats, 14:0, fed as a synthetic triglyceride, was less cholesterolemic than 16:0 in a majority of subjects. ApoE phenotype influenced the cholesterolemic response particularly when diets high in 16:0 were eaten. 相似文献