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121.
Managed care in the US reduces use of health services and hospital admissions. Concerns that cost control could jeopardize quality are widespread. But there is no significant evidence to suggest that this is the case. Managed care produces low patient satisfaction ratings. The US evidence on managed care has little direct relevance to the UK, but elements of it might be usefully tested here. 相似文献
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123.
Hans Juha Exner Eberhard Schlicker 《Naunyn-Schmiedeberg's archives of pharmacology》1995,351(1):46-52
Mouse or rat brain cortex slices were preincubated with 3H-noradrenaline and superfused with physiological salt solution containing desipramine. We studied the effects of prostaglandin E2 (PGE2), prostaglandin D2 (PGD2) and related drugs on the electrically evoked (50 mA, 2 ms, 0.3 Hz) tritium overflow.PGE2 inhibited the electrically evoked tritium overflow from mouse brain cortex slices; the maximum effect of PGE2 (79010) was attenuated by the 2-adrenoceptor agonist talipexole (to 52010) and enhanced by the 2-adrenoceptor antagonist rauwolscine (to 92%). Rauwolscine was added to the superfusion medium in all subsequent experiments. The effect of PGE2 was readily reversible upon withdrawal from the medium and remained constant upon prolonged exposure of the tissue to the prostanoid. Studies with EP receptor agonists, mimicking the inhibitory effect of PGE2, showed the following potencies (pIC50): sulprostone (8.22); misoprostol (8.00); PGE2 (7.74); PGEZ (7.61); iloprost (5.86). The concentration-response curve of PGE2 was marginally shifted to the right by the EP1 receptor antagonist AH 6809 (6-isopropoxy-9-oxoxanthene-2-carboxylic acid; apparent pA2 3.97) and by the TP receptor antagonist vapiprost (4.50). AH 6809, by itself, did not affect the evoked overflow whereas vapiprost increased it. PGD2 inhibited the evoked overflow at high concentrations (pIC50 4.90); this effect was not altered by the DP receptor antagonist BW A868C (3-benzyl-5-(6-carboxyhexyl)-1-(2-cyclohexyl-2hydroxyethylamino)hydantoin), which, by itself, did not affect the evoked overflow. Indometacin slightly increased the evoked overflow and tended to increase the inhibitory effect of PGE2. PGE2 inhibited the electrically evoked tritium overflow also in rat brain cortex slices. The maximum effect (obtained in the presence of rauwolscine) was 61%; the pIC30 value was 7.67.The present study suggests that PGE2 inhibits noradrenaline release from mouse brain cortex via EP3 receptors and that its maximum effect is more marked in the mouse than in the rat. The inhibitory effect of PGD2 (in the mouse brain) does not involve DP receptors and may also be related to EP3 receptors. The EP3 receptors interact with a2-adrenoceptors and may be activated by endogenous prostanoids. 相似文献
124.
There is growing interest in the development and application of standards for the health care to both promote quality assurance but also to improve the processes by which health services are held accountable to the public. This paper maps the development of organisational accreditation systems in the USA, Canada, Australia and the United Kingdom. In the USA, accreditation, which began as a means of ensuring the correct environment for clinical practice has developed into a form of public regulation. In the United Kingdom, many different approaches to the setting of standards and their assessment has created a variety of accreditation systems. The case studies demonstrate that as the concept of accreditation diffuses into the health care systems of different countries, it is being adapted to meet the wider policy needs of different national circumstances. 相似文献
125.
Chinman MJ Allende M Weingarten R Steiner J Tworkowski S Davidson L 《The journal of behavioral health services & research》1999,26(2):211-218
Although consumers have made significant gains in having their voices heard in several areas within mental health, they have made less progress in being able to collaborate with their own treaters in setting treatment goals. On the basis of several years of groundwork by staff at the Connecticut Mental Health Center (CMHC), the Patient Care Committee conducted a needs assessment of providers and consumers to assess both groups' current involvement, interest in, and attitudes toward collaborative treatment planning. The results indicate that providers tend to place much of the responsibility for the difficulties in implementing collaborative treatment planning on consumers. Also, providers tend to underestimate consumers' interest in participating in this process. Implications of these findings for the development of an agency-wide training to enhance the collaborative nature of treatment planning are discussed. 相似文献
126.
Steiner MJ Hertz-Picciotto I Raymond E Trussell J Wheeless A Schoenbach V 《Contraception》1999,60(3):137-143
Researchers have cautioned against generalizing results from contraceptive trials because these studies rely on self-selected participants meeting strict selection criteria who may differ from typical users. Using information collected on daily diaries, we reanalyzed data from the recently completed Reality female condom clinical trial to evaluate factors that influence the probability of pregnancy. Noncompliant women, women with less variable menstrual cycles (17-43 days), and women engaging in intercourse frequently (> or = 11 acts per month) were more likely to conceive during this 6-month trial. The adjusted hazard ratios and 95% confidence intervals for these three covariates were 6.1 (2.0-18.7), 7.2 (1.0-54.3), and 2.0 (0.7-5.3), respectively. The strict selection criteria used in this study failed to recruit a homogeneous cohort with respect to factors that influence the risk of pregnancy. The overall pregnancy rate does not pertain to individual study participants, but rather represent average effects for a population with the particular mix of characteristics found in this study. In particular, we not only confirm the well known importance of compliance and the obvious role of frequency of intercourse, but also demonstrate that women with cycles outside the range of 17-43 days appear to be at a much lower risk of pregnancy. 相似文献
127.
Althouse LA Stritter FT Steiner BD 《Advances in health sciences education : theory and practice》1999,4(2):111-122
The influence of a role model is a frequently cited factor in choosing a specialty choice among medical students, particularly
primary care oriented students. While many studies have looked at role modeling from students' perspectives, very few have
considered role modeling characteristics from the perspective of the role models. This study, using the principles of Bandura's
social learning theory, determined and illuminated the characteristics and teaching methods associated with positive role
modeling in clinical education from the perspective of the role model. A qualitative approach employing interviews and observations
was used. Five themes emerged: the role models' approaches to teaching, their attitudes towards teaching and learning, their
emphasis on clinical competence in their teaching, their roles external to their specific responsibilities, and their general
affect. We found that role models were similar in their views of teaching and working with students. Also, their teaching
characteristics were similar to the recommended approaches found in the literature and adhered to the principles of social
learning theory. Role models were attentive to the needs of the students and tailored their teaching appropriately. They provided
students with ample patient interaction so that students could apply their classroom knowledge. They also demonstrated how
rewarding being an effective physician can be.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
128.
129.
130.
Hamstring tendon grafts for reconstruction of the anterior cruciate ligament: biomechanical evaluation of the use of multiple strands and tensioning techniques 总被引:33,自引:0,他引:33
Hamner DL Brown CH Steiner ME Hecker AT Hayes WC 《The Journal of bone and joint surgery. American volume》1999,81(4):549-557
BACKGROUND: Our hypothesis that multiple, equally tensioned strands of hamstring graft used for reconstruction of the anterior cruciate ligament are stronger and stiffer than ten-millimeter patellar ligament grafts was tested biomechanically with use of tendons from cadavera. METHODS: In the first part of the study, we measured the strength and stiffness of one, two, and four-strand hamstring grafts, from fresh-frozen cadaveric knees, that had been tensioned equally when clamped. In the second part of the study, we compared four-strand grafts to which tension had been applied by hand and then clamped with similar grafts to which tension had been applied with weights and then clamped. The grafts for the two experiments were obtained from thirty-four paired and ten unpaired knees. We also studied the effects of cooling on the biomechanical properties of grafts by comparing patellar ligament grafts tested at 13 degrees Celsius with those tested at room temperature. RESULTS: Two equally tensioned gracilis strands had 185 percent of the strength and 210 percent of the stiffness (1550+/-428 newtons and 336+/-141 newtons per millimeter, respectively) of one gracilis strand (837+/- 138 newtons and 160+/-44 newtons per millimeter, respectively). Two equally tensioned semitendinosus strands had 220 percent of the strength and 220 percent of the stiffness (2330+/-452 newtons and 469+/-185 newtons per millimeter, respectively) of one semitendinosus strand (1060+/-227 newtons and 213+/-44 newtons per millimeter, respectively). Four combined strands (two gracilis strands and two semitendinosus strands) that were equally tensioned with weights and clamped had the additive tensile properties of the individual strands. With the numbers available, four combined strands that were manually tensioned and clamped were not found to be significantly stronger or stiffer than two semitendinosus strands that were equally tensioned with weights (p>0.07). CONCLUSIONS: Four combined strands that were equally tensioned with weights and clamped were stronger and stiffer than all ten-millimeter patellar ligament grafts that have been described in previous reports. All strands of a hamstring graft must be equally tensioned for the composite to have its optimum biomechanical properties. CLINICAL RELEVANCE: Because of the well recognized donor-site morbidity associated with the use of patellar ligament grafts for reconstruction of the anterior cruciate ligament, multiple-strand hamstring-tendon grafts have become an increasingly popular choice. Our data demonstrate that equally tensioned four-strand hamstring-tendon grafts have initial tensile properties that are higher than those reported for ten-millimeter patellar-ligament grafts; thus, from a biomechanical point of view, they seem to be a reasonable alternative. 相似文献