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41.
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A postal survey of recently appointed consultant paediatricians was undertaken to determine whether they perceived their training had adequately equipped them for their current job. The response rate was 69% (207/299). After excluding replies from consultants trained outside the UK the analysis was carried out on 167 replies. Trainees held a mean 5.2 posts during general and higher professional training, necessitating a mean 1.8 house moves. Altogether 82% felt moves were beneficial to training but 46% found moves 'very disruptive' to family life. Only 12% of district general hospital and 22% of teaching hospital senior registrars took two research sessions a week. Supervision and training in research was absent or poor for more than 60%; 24% felt major changes and 55% moderate changes were needed to current training. Training in non-clinical skills was particularly in demand and a curriculum for both trainers and trainees with regular appraisals is required. Research at senior registrar level needs review and educational methods improved to achieve better training in a shorter period. 相似文献
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The purpose of this study was to investigate the prevalence and aetiology of carpal tunnel syndrome (CTS) and the effect of open carpal tunnel decompression (CTD) in a group of patients on renal haemodialysis. In 91 patients attending a Renal Unit who were assessed only by clinical means, the prevalence of CTS was 7.1%. CTS development was not significantly correlated with known risk factors, in particular duration of dialysis and presence of an artero-venous fistula on the symptomatic limb. CTD led to a mean symptom-free period of 12 years. In summary, CTS is a frequent and serious disease affecting renal dialysis patients, but its aetiology remains uncertain. Nevertheless, CTD is an effective and lasting treatment for this condition. 相似文献
46.
Computed tomography of the infratemporal fossa 总被引:2,自引:0,他引:2
47.
Osteoblast apoptosis and bone turnover. 总被引:7,自引:0,他引:7
J M Hock V Krishnan J E Onyia J P Bidwell J Milas D Stanislaus 《Journal of bone and mineral research》2001,16(6):975-984
With the discoveries of different death mechanisms, an emerging definition of apoptosis is the process of cell death associated with caspase activation or caspase-mediated cell death. This definition accepts that caspases represent the final common mechanistic pathway in apoptosis. Apoptosis may be triggered either by activation events that target mitochondria or endoplasmic reticulum or by activation of cell surface "death receptors," for example, those in the tumor necrosis factor (TNF) superfamily. In the postnatal and adult skeleton, apoptosis is integral to physiological bone turnover, repair, and regeneration. The balance of osteoblast proliferation, differentiation, and apoptosis determines the size of the osteoblast population at any given time. Although apoptosis has been recorded in many studies of bone, the selective mechanisms invoked in the different models studied rarely have been identified. This review offers a broad overview of the current general concepts and controversies in apoptosis research and then considers specific examples of osteoblast apoptosis pertinent to skeletal development and to the regulation of bone turnover. In reviewing selected work on interdigital apoptosis in the developing skeleton, we discuss the putative roles of the bone morphogenetic proteins (BMPs), Msx2, RAR-gamma, and death inducer obliterator 1 (DIO-1). In reviewing factors regulating apoptosis in the postnatal skeleton, we discuss roles of cytokines, growth factors, members of the TNF pathway, and the extracellular matrix (ECM). Finally, the paradoxical effects of parathyroid hormone (PTH) on osteoblast apoptosis in vivo are considered in the perspective of a recent hypothesis speculating that this may be a key mechanism to explain the anabolic effects of the hormone. An improved understanding of the apoptotic pathways and their functional outcomes in bone turnover and fracture healing may facilitate development of more targeted therapeutics to control bone balance in patients with osteoporosis and other skeletal diseases. 相似文献
48.
Blood loss and replacement in total hip arthroplasty: a multicenter study. The Preoperative Autologous Blood Donation Study Group 总被引:1,自引:0,他引:1
To determine blood loss, the number of transfusions, and the hemoglobin levels achieved in patients via transfusion in the course of total hip arthroplasty, 324 patient records from 1987 through 1989 were reviewed at three university and three community hospitals. Calculated blood loss was 3.2 +/- 1.3 units in primary procedures and 4.0 +/- 2.1 units in revision procedures (mean +/- SD). Of 777 red cell units transfused, 455 (59%) were autologous units. Transfused patients received 2.0 +/- 1.8 units for primary procedures and 2.9 +/- 2.3 units for revision procedures (mean +/- SD). The maximum number of units given to 95 percent of the transfused patients was 4 for primary procedures and 6 for revision procedures. The mean postoperative hemoglobin level after all transfusions was 103 to 110 g per L, regardless of patient age group of physical status, autologous donor status, or hospital. No difference in length of hospital stay was observed for patients less than 65 years old with hemoglobin concentrations of 80 to 139 g per L at discharge. 相似文献
49.
ObjectiveTo estimate the cost and health outcomes associated with a new HIV testing strategy that utilizes routine-based clinical reminders.MethodsWe conducted an economic analysis of 1) traditional pretest/post-test counseling; 2) counseling and a new clinical reminders system; and 3) only clinical reminder in the veterans’ health care system. A payer-perspective decision model was conducted to calculate the 1-year budget impact of three HIV testing strategies. Parameter values were obtained from the literature, including patients’ probability of accepting test, and costs associated with HIV testing procedures. Deidentified patient data, including total population screened and number of new HIV cases, were collected from one clinic in Los Angeles, California, from August 2004 to December 2011. Annual total costs and costs per new case were calculated on the basis of parameter values and patient data. Sensitivity analyses were conducted to evaluate the robustness of the critical variable on costs.ResultsThe total cost of the clinical reminder system with pretest counseling was $81,726 over 1 year compared with $109,208 for traditional HIV testing. Under a clinical reminder system with no pretest counseling, the number of HIV tests performed and the number of new diagnoses increased for that year. In addition, cost per new diagnoses was the lowest.ConclusionsThe clinical reminder system can reduce the cost per cases identified and promote better performance of HIV testing compared with traditional HIV testing. The fundamental decision model can be used for hospital facilities outside the Veteran Affairs adopting a similar program for improving the HIV testing rate. 相似文献
50.
The Toxicity of Glyphosate and Several Glyphosate Formulations to Four Species of Southwestern Australian Frogs 总被引:6,自引:0,他引:6
The acute toxicity of technical-grade glyphosate acid, glyphosate isopropylamine, and three glyphosate formulations was
determined for adults of one species and tadpoles of four species of southwestern Australian frogs in 48-h static/renewal
tests. The 48-h LC50 values for Roundup? Herbicide (MON 2139) tested against tadpoles of Crinia insignifera, Heleioporus eyrei, Limnodynastes dorsalis, and Litoria moorei ranged between 8.1 and 32.2 mg/L (2.9 and 11.6 mg/L glyphosate acid equivalent [AE]), while the 48-h LC50 values for Roundup? Herbicide tested against adult and newly metamorphosed C. insignifera ranged from 137–144 mg/L (49.4–51.8 mg/L AE). Touchdown? Herbicide (4 LC-E) tested against tadpoles of C. insignifera, H. eyrei, L. dorsalis, and L. moorei was slightly less toxic than Roundup? with 48-h LC50 values ranging between 27.3 and 48.7 mg/L (9.0 and 16.1 mg/L AE). Roundup? Biactive (MON 77920) was practically nontoxic
to tadpoles of the same four species producing 48-h LC50 values of 911 mg/L (328 mg/L AE) for L. moorei and >1,000 mg/L (>360mg/L AE) for C. insignifera, H. eyrei, and L. dorsalis. Glyphosate isopropylamine was practically nontoxic, producing no mortality among tadpoles of any of the four species over
48 h, at concentrations between 503 and 684 mg/L (343 and 466 mg/L AE). The toxicity of technical-grade glyphosate acid (48-h
LC50, 81.2–121 mg/L) is likely to be due to acid intolerance. Slight differences in species sensitivity were evident, with L. moorei tadpoles showing greater sensitivity than tadpoles of the other four species. Adult and newly emergent metamorphs were less
sensitive than tadpoles.
Received: 19 February 1998/Accepted: 16 August 1998 相似文献