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31.
BT Hirsch 《Canadian Metallurgical Quarterly》1997,(336):33-41
Economic theory and evidence indicate that workers, employers, and healthcare personnel respond to the incentives built into state workers' compensation systems. Although empirical studies cannot provide precise estimates of the quantitative effects resulting from specific policy changes, research is useful in evaluating the qualitative effects of alternative policies. Studies show that workers' compensation claims are higher the more generous the level of benefits, the shorter the waiting period, and the more readily available is information on benefits to workers. States that decrease real benefit levels and lengthen the period required before workers are compensated for lost earnings can constrain future growth in workers' compensation costs, while continuing to provide partial compensation for workers with the most serious injuries. The most difficult problem facing policymakers is to design and implement reforms that take into account what are often the incompatible incentives of workers, employers, and medical care providers. 相似文献
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BT Holt NL Parks GA Engh JM Lawrence 《Canadian Metallurgical Quarterly》1997,20(12):1121-4; discussion 1124-5
One hundred thirty-six primary total knee arthroplasty patients were randomized for the use of closed-suction, nonreinfusable wound drains. Blood loss was identical in the drained and undrained groups. Forty percent of undrained wounds compared with 0% of drained wounds required dressing reinforcement. Sixty-nine percent of undrained wounds compared with 39% of drained wounds developed ecchymosis, measuring 92 cm2 in the undrained group and 28 cm2 in the drained group. This study concludes that a simple wound drain effectively minimizes the undesirable accumulation of blood in the surrounding soft tissues and the postoperative wound dressing after total knee arthroplasty. 相似文献
34.
FO Zelaya SE Rose PF Nixon BT Wholohan AJ Bower C Zimitat J Schoutrop DM Doddrell 《Canadian Metallurgical Quarterly》1995,13(4):555-561
Contrast-enhanced T1-weighted spin-echo magnetic resonance imaging (MRI) has demonstrated that Gd-diethylenetriaminepentaacetate (Gd-DTPA), which normally does not cross the blood-brain or blood-CSF barriers, does so approximately 40 min after administration of glucose to a vitamin B1 deficient rat. The period of the onset of this blood-CSF or blood-brain barrier dysfunction coincides with our previous observations of accumulation of glutamate or glutamate derivatives following an equivalent glucose load under identical conditions of thiamin deficiency, consistent with a relationship between these two observations. The dysfunction was reversed when a thiamin deficient animal was made thiamin replete. 相似文献
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B Balasa JD Davies J Lee A Good BT Yeung N Sarvetnick 《Canadian Metallurgical Quarterly》1998,161(8):4420-4427
IL-10 is essential for an early phase of diabetes in nonobese diabetic (NOD) mice, but later becomes protective against its development. The mechanism by which IL-10 mediates the pathway to diabetes in these mice is unknown. Herein, we dissected the cellular and costimulation requirements for diabetes in transgenic (tg) NOD mice that expressed IL-10 in their pancreatic islets (IL-10-NOD mice). We found that IL-10 alone did not cause diabetes because the offspring (IL-10-NOD-scid mice) from back-crosses of IL-10-NOD mice with NOD-scid mice had no diabetes. Moreover, these IL-10-NOD-scid mice were free of lymphocytic infiltration. Treatment of IL-10-NOD mice with depleting anti-CD4 mAb or control mAb had no effect on diabetes. Surprisingly, depletion of CD8+ T cells by treatment with the corresponding mAb inhibited diabetes without attenuating insulitis, demonstrating a critical role for CD8+ T cells in the disease process. Interestingly, B cell-deficient IL-10-NOD mice readily developed diabetes with kinetics and incidence similar to those observed in wild-type mice, demonstrating that B lymphocytes as APCs were not required in the disease process. Administration of anti-CD40 ligand (CD40L) mAb did not prevent disease, indicating that CD40/CD40L costimulation is not required for diabetes in IL-10-NOD mice. Immunization of IL-10-NOD mice with CFA or heat-shock protein 65, known to block diabetes in NOD mice, had no effect on their diabetes. We demonstrate that IL-10 contributes early to the pathology of diabetes via a CD8+ T cell pathway, eliminating the requirement for B lymphocytes and CD40-CD40L costimulation. Our findings provide a mechanism for the participation of IL-10 in the early development of diabetes. 相似文献
38.
OBJECTIVE: To evaluate the discrepancy index between the clinical and histological diagnosis and the prevalence of epithelial dysplasia and carcinoma in 45 patients with potentially malignant epithelial oral lesions (PMEL). PATIENTS AND METHODS: We submitted 45 patients with PMEL to clinical examination and obtained a biopsy from each. The results of histological diagnosis were compared to the clinical diagnosis. RESULTS: Clinical diagnosis showed that the most common PMEL was leukoplakia followed by lichen planus and by actinic cheilitis associated with leukoplakia. The most common site was the buccal mucosa. Histological diagnosis revealed that 46.7% of the PMEL were lichen planus. The discrepancy index between clinical and histological diagnosis was 24.4%. The higher discrepancy index occurred among leukoplakias. The prevalence of epithelial dysplasia and carcinoma was 17.8%. CONCLUSIONS: We conclude that all PMEL should be submitted to a microscopic analysis because the discrepancy between clinical and histological diagnosis was present in a quarter of these lesions. Otherwise, the epithelial dysplasia and carcinoma were more frequent in the leukoplakias. 相似文献
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JH Morais Cabral A Lee SL Cohen BT Chait M Li R Mackinnon 《Canadian Metallurgical Quarterly》1998,95(5):649-655
More and more elderly subjects are offered for pulmonary resection. The object of this study was to review the results of excision for cancer in octogenarians. PATIENTS: 51 consecutive patients (44 men, 7 women) with a mean age of 82 years (80-91) were operated on. 31 lobectomies, 2 bilobectomies, 13 pneumonectomies, 1 segmental resection and 4 exploratory thoracotomies were carried out. 17 tumours were classed as stage I, 15 as stage II and 15 as stage III. RESULTS: 38 patients (75%) had uncomplicated post-operative periods; the predicted factors for complication were the existence of weight loss and alteration of respiratory function. 2 patients (4%) died in the post-operative phase. Neither the type of operation, the staging or the existence of cardiovascular dysfunction had any influence on the post-operative phase. The level of the survival at 3 and 5 years was 39% and 16% respectively. 30% of the late deaths were related to intercurrent events. CONCLUSIONS: Pulmonary excision may be envisaged in an octogenarian who is in good physical and intellectual state with a limited tumour. This surgery in general is applied to a population which probably only marginally consists of octogenarians but the results here justify their inclusion in the indications for selection. 相似文献