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The conditions for the preparation of a 10% butyl-p-aminobenzoate suspension for epidural administration were investigated. Pharmaceutically acceptable suspensions are composed of butyl-p-aminobenzoate particles dispersed in a solvent consisting of the surfactant polysorbate 80 added to normal saline in a concentration of 0.25 mg/ml. pH Correction is not necessary. The suspensions are sterilized at 120°C followed by special milling procedures to accomplish acceptable particle size. Butyl-p-aminobenzoate suspensions are stable at 4°C during a period of at least four weeks.  相似文献   
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Objectives. To evaluate the cost effectiveness of transurethral microwave thermotherapy relative to medical therapy (alpha-blocking agents) and transurethral resection of the prostate (TURP) for patients with moderate-to-severe benign prostatic hyperplasia (BPH) symptoms.Methods. A cost-effectiveness analysis was performed from the societal perspective for a hypothetical cohort of 65-year-old men with moderate-to-severe BPH symptoms. We calculated the incremental cost effectiveness of thermotherapy relative to medical therapy and TURP during 5 years after treatment initiation. Event probabilities were obtained from published reports, a consensus panel, and the Targis System (Urologix) randomized clinical trial. Costs were estimated using the national Medicare reimbursement schedules. Costs are reported in 1999 U.S. dollars. Total thermotherapy procedure costs were estimated at $2629. Quality-of-life and utility estimates were obtained by interviewing 13 patients with moderate-to-severe BPH symptoms. On the basis of their risk attitudes, patients were classified into risk-averse or non-risk-averse groups. The costs and health effects were discounted at 3% annually.Results. In a hypothetical cohort of 10,000 non-risk-averse patients who were candidates for all three modalities, the 5-year costs were highest for patients undergoing TURP and lowest for those receiving medical therapy ($7334 and $6294, respectively). The thermotherapy group exhibited the highest 5-year utility value (53.52 quality-adjusted life-months). Compared with medical therapy, thermotherapy resulted in an additional 0.23 quality-adjusted life-months, with an incremental cost of $741. This yielded an incremental cost per quality-adjusted life-year gained of $38,664 for thermotherapy compared with medical therapy. Thermotherapy had a higher utility (difference of 1.71 quality-adjusted life-months) and lower cost (difference of $299) compared with TURP and thus was dominant over TURP. The results were similar for a hypothetical cohort of 10,000 risk-averse patients.Conclusions. From a societal perspective, thermotherapy appears to be a reasonable and cost-effective alternative to both medical and surgical treatment. However, the actual treatment decision should be based on multiple factors, only one of which is cost effectiveness.  相似文献   
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Objectives. To present the method used to evaluate the cost effectiveness, from the societal perspective, of transurethral microwave thermotherapy relative to medical therapy (alpha-blocking agents) and transurethral resection of the prostate (TURP) for a hypothetical cohort of 65-year-old men with moderate-to-severe benign prostatic hyperplasia (BPH) symptoms.Methods. We constructed a decision-analytic Markov model with 25 health states describing the 3 treatments, 5 short-term clinical events, and 17 possible long-term outcomes. Each health state had an associated cost and utility. Utility weights, reflecting an individual’s preference for a specific health outcome, range from 0, indicating death, to 100, indicating perfect health. Utility estimates were obtained by interviewing 13 men with moderate-to-severe BPH symptoms using the standard gamble preference measurement technique. On the basis of their risk attitudes, the patients were classified as risk averse or non-risk averse. The rates of remission, temporary and permanent adverse events, retreatment, and mortality were obtained from the Targis System (Urologix) randomized clinical trial, published reports, and a consensus panel. The costs during the 5 years after treatment initiation were estimated using national Medicare reimbursement schedules. The costs are reported in 1999 U.S. dollars.Results. Eliciting utility values from patients with BPH was feasible and generated internally consistent and externally valid measures. In the non-risk-averse group, the utility value for significant remission, moderate remission, no remission, and worsening BPH symptoms without an adverse event was 99.1, 97.1, 94.4, and 87.3, respectively. As expected, the risk-averse individuals (n = 6) exhibited higher utility values than those in the non-risk-averse group (n = 7). In the non-risk-averse group, thermotherapy was the preferred treatment, and in the risk-averse group, medical therapy was preferred. In both groups, TURP was the least preferred therapy. The initial thermotherapy procedure costs without complications were estimated at $2629, and the initial TURP procedure costs without complications were estimated at $4597. Time-dependent probabilities were developed to reflect treatment durability.Conclusions. The resulting model parameters appear to be suitable for evaluating the cost effectiveness of thermotherapy relative to medical therapy and TURP in 65-year-old men with moderate-to-severe BPH symptoms.  相似文献   
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IL Ackerman  CA Karn  SC Denne  GJ Ensing  CA Leitch 《Pediatrics》1998,102(5):1172-1177
OBJECTIVE: The purpose of this study was to determine the effect of left-to-right shunting on the resting energy expenditure (REE), total energy expenditure (TEE), and energy intake in a group of 3- to 5-month-old infants with moderate to large unrepaired ventricular septal defects (VSDs) compared with age-matched, healthy infants. METHODS: Eight infants with VSDs and 10 healthy controls between 3 to 5 months of age participated in the study. Indirect calorimetry was used to measure REE and the doubly-labeled water method was used to measure TEE and energy intake. An echocardiogram and anthropometric measurements were performed on all study participants. Daily urine samples were collected at home for 7 days. Samples were analyzed by isotope ratio mass spectrometry. Data were compared using analysis of variance. RESULTS: No significant differences were found in REE (VSD, 42.2 +/- 8.7 kcal/kg/d; control, 43.9 +/- 14.1 kcal/kg/d) or energy intake (VSD, 90.8 +/- 19.9 kcal/kg/d; control, 87.1 +/- 11.7 kcal/kg/d) between the groups. The percent total body water was significantly higher in the VSD infants and the percent fat mass was significantly lower. TEE was 40% higher in the VSD group (VSD, 87.6 +/- 10.8 kcal/kg/d; control, 61.9 +/- 10.3 kcal/kg/d). The difference between TEE and REE, reflecting the energy of activity, was 2.5 times greater in the VSD group. CONCLUSIONS: REE and energy intake are virtually identical between the two groups. Despite this, infants with VSDs have substantially higher TEE than age-matched healthy infants. The large difference between TEE and REE in VSD infants suggests a substantially elevated energy cost of physical activity in these infants. These results demonstrate that, although infants with VSDs may match the energy intake of healthy infants, they are unable to meet their increased energy demands, resulting in growth retardation.  相似文献   
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Problem: Systems-based practice focuses on the organization, financing, and delivery of medical services. The American Association of Medical Colleges has recommended that systems-based practice be incorporated into medical schools’ curricula. However, experiential learning in systems-based practice, including practical strategies to improve the quality and efficiency of clinical care, is often absent from or inconsistently included in medical education. Intervention: A multidisciplinary clinician and nonclinician faculty team partnered with a cardiology outpatient clinic to design a 9-month clerkship for 1st-year medical students focused on systems-based practice, delivery of clinical care, and strategies to improve the quality and efficiency of clinical operations. The clerkship was called the Action Research Program. In 2013–2014, 8 trainees participated in educational seminars, research activities, and 9-week clinic rotations. A qualitative process and outcome evaluation drew on interviews with students, clinic staff, and supervising physicians, as well as students’ detailed field notes. Context: The Action Research Program was developed and implemented at the University of California, San Francisco, an academic medical center in the United States. All educational activities took place at the university's medical school and at the medical center's cardiology outpatient clinic. Outcome: Students reported and demonstrated increased understanding of how care delivery systems work, improved clinical skills, growing confidence in interactions with patients, and appreciation for patients’ experiences. Clinicians reported increased efficiency at the clinic level and improved performance and job satisfaction among medical assistants as a result of their unprecedented mentoring role with students. Some clinicians felt burdened when students shadowed them and asked questions during interactions with patients. Most student-led improvement projects were not fully implemented. Lessons Learned: The Action Research Program is a small pilot project that demonstrates an innovative pairing of experiential and didactic training in systems-based practice. Lessons learned include the need for dedicated time and faculty support for students’ improvement projects, which were the least successful aspect of the program. We recommend that future projects aiming to combine clinical training and quality improvement projects designate distinct blocks of time for trainees to pursue each of these activities independently. In 2014–2015, the University of California, San Francisco School of Medicine incorporated key features of the Action Research Program into the standard curriculum, with plans to build upon this foundation in future curricular innovations.  相似文献   
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