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排序方式: 共有1957条查询结果,搜索用时 15 毫秒
101.
Moayyedi P Wardman M Toner J Ryan M Duffett S 《European journal of gastroenterology & hepatology》2002,14(4):429-433
OBJECTIVE: The Department of Health states that patients with suspected cancer should be seen within 2 weeks, and the Patients' Charter suggests that patients should not wait for more than 30 min in outpatients. Decisions such as these are often made with little assessment of patient preferences. We have elicited patient preferences for the optimal use of time in the outpatient clinic. DESIGN: Questionnaire survey eliciting preference between different clinic scenarios evaluated using discrete choice conjoint analysis. SETTING AND PARTICIPANTS: Patients attending a teaching hospital gastroenterology outpatient clinic. MAIN OUTCOME MEASURES: The relative importance of time spent on the waiting list, time waiting in the clinic, time spent with the specialist, and time waiting for investigation was assessed using a logit model. RESULTS: Patients placed a similar value on waiting for investigation and time spent on the waiting list. A clinic that had a 2-month waiting list but offered immediate investigations would therefore be more popular than a clinic that had a 2-week waiting list but whose investigations were deferred for 3 months. Patients would be prepared to spend an extra 30 min in the waiting room if they spent 1 month less on the waiting list or waiting for investigation. Time spent with a specialist is valued, and patients would be prepared to spend an extra 3 min waiting in the clinic for every extra minute spent with the doctor. CONCLUSIONS: The present Department of Health recommendations and the Patients' Charter are too simplistic and do not take into account patient preferences. 相似文献
102.
Dose-finding and pharmacokinetic study of cisplatin, gemcitabine, and SU5416 in patients with solid tumors. 总被引:19,自引:0,他引:19
Bart C Kuenen Lee Rosen Egbert F Smit Mandy R N Parson Marcel Levi Rita Ruijter Holger Huisman Marc A Kedde Paul Noordhuis Wim J F van der Vijgh Godefridus J Peters Gillian F Cropp Paul Scigalla Klaus Hoekman Herbert M Pinedo Giuseppe Giaccone 《Journal of clinical oncology》2002,20(6):1657-1667
PURPOSE: To investigate the feasibility and pharmacokinetics of the combination cisplatin, gemcitabine, and SU5416. PATIENTS AND METHODS: Patients received cisplatin 80 mg/m(2) on day 1, gemcitabine 1,250 mg/m(2) on days 1 and 8, repeated every 3 weeks, and SU5416 (85 and 145 mg/m(2)) intravenously twice weekly. Pharmacokinetics of all three agents, side effects, and antitumor response were investigated in patients with solid tumors amenable to therapy with cisplatin/gemcitabine. RESULTS: In the first cohort of three patients entered at the 85 mg/m(2) dose, no dose-limiting toxicities were observed. In the next cohort (145 mg/m(2)), three patients developed a thromboembolic event. After entry was restricted to patients with low thromboembolic risk, three additional patients enrolled at 145 mg/m(2) developed a thromboembolic event. The dose was then reduced to 85 mg/m(2) in all patients still on the study, and three additional patients were entered on this dose level. In 19 treated patients, eight patients developed nine thromboembolic events (three transient ischemic attacks, two cerebrovascular accidents, and four deep venous thromboses). The most common toxicities observed were those previously reported for SU5416 alone (headache and phlebitis) and for this chemotherapy regimen (nausea, thrombocytopenia, and leucopenia). No significant pharmacologic interaction among the three drugs was observed. Response rates were similar to those expected in the patient population selected for this study. Analysis of variables of the coagulation cascade and of vessel wall activation was performed in three patients and showed significant increases in thrombin generation and endothelial cell perturbation in a treatment cycle-dependent manner. CONCLUSION: The incidence of thromboembolic events, possibly related to the particular regimen tested in this study, discourages further investigation of this regimen. 相似文献
103.
Temperature regulation was evaluated in senescent (34-40 month old) and adult (8-9 month old) female Iva:WIWU and Emd:Wi-AF/Han rats. Injection of 1.5 mg/kg BW apomorphine HCl or 1.0 mg/kg BW oxotremorine sesquifumarate produced comparable maximal hypothermic responses in adult and senescent rats. However, the latency to reach maximal hypothermia after oxotremorine (but not apomorphine) was longer in senescent than in adult rats of both strains. 相似文献
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107.
PURPOSE: To correct MR spectra for local changes in the coil sensitivity for a widely used coil setup, consisting of a transmitting body coil and a receive-only head coil. MATERIALS AND METHODS: The method relies on the reciprocity principle for the body coil and a correction factor for signal amplitudes between body coil and head coil. The correction is based either on the local flip angle dependence of the stimulated echo acquisition mode signal (TFC) or on the automatic RF calibration (RFC). Water phantoms of different volumes were used to simulate variable coil loads, and B1 field inhomogeneities were assessed by varying the voxel position. Furthermore, the correction was tested by longitudinal measurements in one volunteer. RESULTS: The correction in vitro yields a reduction of the variation coefficient of the water signal by about 77% (TFC) and 66% (RFC) for different coil loads, as well as 55% (TFC) for variable voxel positions. Slightly lower reductions were assessed for the variation coefficients of the metabolite signals in vivo. CONCLUSION: This approach adequately compensates for local changes in coil sensitivity, when acquiring MR spectra with a receive-only head coil. 相似文献
108.
Harting J van Assema P Ruland E van Limpt P Gorgels T van Ree J Vermeer F de Vries NK 《American journal of preventive medicine》2005,29(2):113-119
BACKGROUND: Although reporting on the healthcare-setting level of continuance or discontinuance of an intervention once a trial is completed has been recommended, such "real-world" diffusion studies are rare. The present example was made possible by funding to explore opportunities for post-trial implementation of an innovative health counseling intervention for cardiovascular prevention in The Netherlands. METHODS: Between 2001 and 2004, in a longitudinal case study, we compared two healthcare settings: a cardiology outpatient clinic and general practices. Rogers' diffusion of innovations theory served as the theoretical background. Information was extracted from minutes of meetings and informal conversations with health counselors, and checked by the project manager. Additional data were collected from physicians with a short questionnaire. RESULTS: Implementation of the health counseling intervention was successful in the cardiology outpatient clinic, but was unsuccessful in the general practices. Success was related to a centralized diffusion system, stronger "change agent" efforts, avoidance of post-trial interruption of service delivery, easily achievable "reinventions," and positive physician perceptions of the service (i.e., not complex and compatible with current practice routines). Support came from changes in the organization of care that created opportunities for, instead of competition with, the innovative service. However, coincidental events may also have played a part. CONCLUSIONS: Our findings confirm the importance of most theoretically predicted individual and organizational diffusion variables. This implies that the implementation of innovative healthcare services requires attention at both levels. 相似文献
109.
Individuals' rationality has been a key issue long debated in Economics. While normative theories establish the way 'rational' consumers should behave, many empirical studies have documented numerous systematic violations of normative principles. This has led some to question the validity of classic economic models as an adequate approximation of individuals' real decision-making. This paper aims to shed more light on this debate. A stated preference choice experiment was set up to test rational choice properties. Attention was given to the extent to which satisfaction of such tests is related to both the complexity of the design, and subject characteristics. Quantitative and qualitative methods are applied. The majority of respondents passed the rationality tests. Satisfaction of the tests was sensitive to normatively irrelevant factors such as the complexity of the task and demographic characteristics. A significant proportion of those individuals who 'failed' seem to have reformulated the experiment in some way in their mental process. Implications for the design and analyses of future DCEs are discussed. 相似文献
110.
The authors wished to assess medical students' attitudes towards communication skills learning, and to validate the use of the Communication Skills Attitude Scale (CSAS) in a different population. This cross-sectional study of Years 1-3 MBChB students, University of Aberdeen, in 2002-03 (overall response rate=86.2%) identified significant differences in attitudes to communication skills teaching by year of study and gender. PAS (positive attitudes scores) for Year 1 were significantly higher than those for Years 2 and 3. NAS (negative attitudes scores) for Year 1 were significantly lower than the scores for Year 2 but not Year 3. The scores for Years 2 and 3 were not significantly different. Female students had a significantly higher mean PAS score and lower mean NAS score than males, and were more likely to disagree that their communication and clinical skills were competent. While cohort effects may be present, it seems that attitudes towards communication skills learning are positive initially, becoming less so until students experience interacting with patients. Differences between male and female students reflect those seen in previous studies. The findings presented support the use of the CSAS as an appropriate tool to measure attitudes in a wide population of medical students. 相似文献