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991.
OBJECTIVE: To examine the conditions necessary to make screening for microalbuminuria in patients with insulin dependent diabetes mellitus cost effective. DESIGN: This economic evaluation compared two strategies designed to prevent the development of end stage renal disease in patients with insulin dependent diabetes with disease for five years. Strategy A, screening for microalbuminuria as currently recommended, was compared with strategy B, a protocol in which patients were screened for hypertension and macroproteinuria. INTERVENTION: Patients identified in both strategies were treated with an angiotensin converting enzyme inhibitor. SETTING: Computer simulation. MAIN OUTCOME MEASURES: Strategy costs and quality adjusted life years (QALYs). RESULTS: The model predicted that strategy A would produce an additional 0.00967 QALYs at a present value cost of $261.53 (1990 US$) per patient (or an incremental cost/QALY of $27,041.69) over strategy B. The incremental cost/QALY for strategy A over B was sensitive to several variables. If the positive predictive value of screening for microalbuminuria (impact of false label and unnecessary treatment) is < 0.72, the effect of treatment to delay progression from microalbuminuria to macroproteinuria is < 1.6 years, the cumulative incidence of diabetic nephropathy falls to < 20%, or > 64% of patients demonstrate hypertension at the onset of microalbuminuria, then the incremental costs/QALY will exceed $75,000. CONCLUSION: Whether microalbuminuria surveillance in this population is cost effective requires more information. Being aware of the costs, recommendation pitfalls, and gaps in our knowledge should help focus our efforts to provide cost effective care to this population. 相似文献
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994.
A simplified method for the determination of alpha-tocopherol concentration in beef muscle was developed and evaluated. The method consists of a saponification step applied to 1-g samples of intact, fresh muscle, followed by a single isooctane extraction of the saponified samples. alpha-Tocopherol in the extract was separated by normal phase chromatography and quantified by fluorescence detection. A single extraction with the simplified method accounted for 95% of the total muscle alpha-tocopherol concentration obtained by two extractions with the Arnold et al. (J. Food Sci. 58:28, 1993) method. Recovery of added alpha-tocopherol standard after two extractions of a saponified muscle sample was 91% for the simplified method, which was not different (alpha = .78) from recovery using the Arnold method, and the efficiency of the single extraction in the simplified method was 89%. The coefficients of variation for the simplified and Arnold methods were both 3.1%. This method should permit the duplicate analysis of 100 fresh muscle samples within 24 h. 相似文献
995.
Buckling behavior of composite plates subjected to bi-axial loading was experimentally determined and numerically analyzed. Modified rectangular specimens were introduced to overcome one of the experimental obstacles in which the loading grips interfere with each other's motion at each corner during the continuous bi-axial compression process. To determine the effects of modifications of the plate specimen, finite element analysis was performed in which the large deflection but small strain conditions were considered. In this paper, three different types of results which were determined from theoretical, numerical and experimental approaches are presented. 相似文献
996.
Reproduction in vertebrates is regulated by internal signals such as hormone levels and by external signals such as social interactions. In an African cichlid fish, Haplochromis burtoni, the effect of social interactions is evident in the hypothalamo-pituitary-gonadal (HPG) axis of males. Territorial males, characterized by aggressive and reproductive activity, have significantly larger hypothalamic gonadotropin-releasing hormone (GnRH)-containing neurons and larger testes than nonterritorial males. Furthermore, a switch in the social status of an adult male causes a corresponding change in GnRH neuron size and testis size. Here we show that the GnRH-containing neurons in the hypothalamus of adult territorial males are also influenced by gonadal hormones. Castration of territorial males caused GnRH neurons to increase in size. This neuronal hypertrophy in castrated animals was prevented either by testosterone (T) or 11-ketotestosterone (KT) treatment. Estradiol (E2) treatment did not reduce GnRH cell size in castrated animals. These results suggest that androgens reduce the size of GnRH cells through negative feedback. Since E2 had no effect, androgen influence on GnRH cell size appears to be independent of aromatization. These data are consistent with the hypothesis that the setpoint for hypothalamic GnRH cell size is determined by social cues and that this setpoint is maintained by negative feedback from gonadal androgens. 相似文献
997.
SE Campbell W Chan KK Wallace J Sunshine SB Gay 《Canadian Metallurgical Quarterly》1995,2(11):1005-1010
RATIONALE AND OBJECTIVES: We surveyed diagnostic radiology group preferences and considerations in hiring radiologists and compared these findings with those of a survey performed in 1990. We sought to identify changes in hiring practices that might have occurred because of socioeconomic changes. We also sought to identify features of job candidates that make them more attractive to hiring groups. METHODS: One hundred surveys were mailed to a stratified random sample of diagnostic radiology groups identified by the American College of Radiology. We solicited information on the importance of various attributes and the level of experience of a candidate, the fellowship training considered most desirable, and the effect of changes in the health care socioeconomic environment. The responses were weighted by group size and geographic location to estimate what results might have been obtained if we had surveyed all groups in the United States. RESULTS: Seventy-five groups returned the survey. The two most important factors in choosing a candidate were motivation and radiologic knowledge. The fellowships that groups that were hiring considered to be the most desirable were body imaging, neuroradiology, and angiography/interventional radiology. Groups overwhelmingly preferred recent training over long experience. CONCLUSION: Fellowship training increases a candidate's marketability, but the two factors that hiring groups consider the most important are motivation and radiologic knowledge. 相似文献
998.
TP Ip DM Hoffman AJ O'Sullivan KC Leung KK Ho 《Canadian Metallurgical Quarterly》1995,80(4):1278-1282
To determine whether adult serum GH-binding protein (GHBP) is regulated by androgen, serum GHBP concentrations were compared between 20 normal and 18 hypogonadal men matched for age and body mass index, and the effect of im testosterone treatment (250 mg testosterone enanthate) on GHBP levels in the 18 hypogonadal men was studied. Nine of the hypogonadal subjects had coexistent GH deficiency. Serum GHBP concentration was measured by a ligand immunofunctional assay. The mean serum GHBP level in untreated hypogonadal men was not significantly different from that of normal men (0.98 +/- 0.15 vs. 1.17 +/- 0.16 nmol/L). The mean serum insulin-like growth factor I (IGF-I) level was significantly lower in the hypogonadal men (132 +/- 22 vs. 206 +/- 17 ng/mL; P < 0.01). Basal testosterone (3.7 +/- 0.7 nmol/L) in hypogonadal men increased during treatment to a mean level of 29.1 +/- 2.8 nmol/L, which was not significantly higher than that in normal men (22.6 +/- 1.9 nmol/L). The mean serum GHBP level in hypogonadal men fell significantly during treatment to 0.60 +/- 0.11 nmol/L (P = 0.0003), whereas the serum IGF-I level rose significantly to 151 +/- 26 ng/mL (P < 0.04). The decrease in GHBP level was significant in both the GH-sufficient and GH-deficient subjects (P < 0.02 in both instances), whereas the increase in IGF-I level was significant in the GH-sufficient group (199 +/- 22 to 235 +/- 29 ng/mL; P < 0.04) but not in the GH-deficient group (53 +/- 7 to 55 +/- 5 ng/mL; P > 0.8). Thus, serum GHBP is normal in hypogonadal men but is reduced by testosterone treatment irrespective of endogenous GH-secretory status. It was concluded that the effect of testosterone on GHBP is pharmacological and occurs independent of GH mediation. 相似文献
999.
I Leibovitch RS Foster KK Kopecky P Albers TM Ulbright JP Donohue 《Canadian Metallurgical Quarterly》1998,16(1):261-268
1000.
The nasolabial flap was used in 11 patients for reconstruction of moderate sized intra-oral defects. There was minimal morbidity of donor and recipient sites in terms of function and cosmesis. The flap was easily harvested, with a reduction in operating time. The superb vascularity and reliability of the flap was demonstrated by the fact that it was possible to use this flap even after a radical neck dissection had been performed on the same side or after radiotherapy. This article describes the authors' experience with the use of the subcutaneously-pedicled, inferiorly-based, double-staged nasolabial flap for intra-oral reconstruction. 相似文献