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71.
We use data from 1983 and 1985 on the volume of Medicare physician services to analyze whether Medicare's Prospective Payment System (PPS), which resulted in a significant decline in hospital spending, led to a partially offsetting increase in real expenditures for physician services. We also analyze the effect of increases in assignment rates, increasing incomes of the elderly, and other factors on real expenditures during this period. Our main conclusion is that PPS has at most a small positive effect on real physician expenditures. Because people spent less time in the hospital, Medicare physician spending declined; but because of incentives to shift radiology and other services out of the hospital, some of this decline was offset. We also conclude that the sharp increase in Medicare assignment rates over this period, along with the rising incomes of the elderly during this period, contributed to the observed growth. 相似文献
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The results of additional validation studies of a sensitive microplate hemagglutination assay for ABO reverse grouping of bloodstains are presented. The results of the validation study demonstrate the reliability of the microplate assay for use in routine serological casework. Based on these studies, the microplate assay has now replaced the Lattes crust test for ABO reverse grouping of bloodstains in the FBI Laboratory. 相似文献
74.
D.S.T Lo T.C Chao S.E Ng-Ong Y.J Yao T.H Koh 《Forensic Science International Supplement Series》1997,90(3):626
Blood previously acidified with aqueous saturated ammonium chloride solution was extracted with ethyl acetate. The dried extract was subjected to acetonitrile–hexane partition. The acetonitrile portion was analysed for the presence of acidic and neutral drugs by HPLC–DAD (200 mm×2.1 mm I.D. microbore ODS-Hypersil column) and GC–FID (25 m narrow-bore×0.25 mm I.D. HP-5 column with 0.33 μm film thickness). The protocol was found to be suitable for both clinical toxicology (including emergency toxicology) and postmortem toxicology. At least 66 drugs of interest were unequivocally identified by RRTs (HPLC) and UV spectra (DAD) match while another 12 were unequivocally identified by double RRTs match (HPLC and GC). Quantitation was facilitated by incorporating calibration blood standards in each assay batch. The five drugs most commonly encountered in clinical blood specimens (1150 cases) were: paracetamol (47.4% of the cases); chlormezanone (6.6%), theophylline (1.74%), naproxen (1.65%) and mefenamic acid (1.56%). The following drugs were detected in toxicologically significant quantities in postmortem blood specimens (245 cases): phenobarbitone (1.22% of the cases), naproxen (0.82%), chlormezanone (0.82%), theophylline (0.82%), carbamazepine (0.41%) and paracetamol (0.41%). 相似文献
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The effect of various stain carriers on the quality and quantity of DNA extracted from dried bloodstains 总被引:1,自引:0,他引:1
Bloodstains were made with 200 microliters blood on each of 11 different common substrates to examine the effect of the stain carrier on the amount and quality of DNA recoverable. High-molecular-weight DNA was extracted from all samples after 2 days. The yield of DNA from each sample varied considerably, not only between the different stain carriers but also within a given category. With a DNA yield of up to 10 micrograms, paper, glass, nylon, wood, smooth leather and wool gave the best results, followed by blue denim and wallpaper (up to 6 micrograms), cotton fabric and carpeting (up to 4 micrograms) and suede (up to 2 micrograms). For several stain carriers the DNA-containing solution was contaminated by chemical substances, which in the case of the blue denim, suede, and carpet samples inhibited the digestion of the DNA with restriction enzymes and prevented DNA typing. The different textures of the stain carriers tested and (as for varying yields on the same carrier) the differing degree of loss of DNA during extraction and the physiological variation in the number of leukocytes in human blood are discussed as possible reasons for the wide range of variation in the amounts of DNA it was possible to extract. 相似文献
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D J WILLIAMS WILLIAM B. STREAN ENRIQUE GARCIA BENGOECHEA 《Juvenile & family court journal》2002,53(2):31-41
This article discusses relevant literature on the potential benefits of sport, recreation, and leisure, and how these benefits relate to rehabilitation of juveniles. Many professionals involved in juvenile rehabilitation believe sport and recreation are beneficial adjuncts to treatment programming; however, it can be difficult to structure sport and recreation in ways that directly correspond to treatment goals. The purpose of this article is to provide insights for professionals working with juveniles on how sport and recreation programming can be an effective means of helping to achieve rehabilitation goals. Attention is given to approaches, particularly the Teaching Games for Understanding model (Bunker & Thorpe, 1982), which can be used to effectively link recreation and sport to the rehabilitation process. 相似文献
80.
Rebecca Emerson Stephen G. Hall Anna Zalewska-Mitura 《Economic Change and Restructuring》1997,30(2-3):75-90
With new technically advanced methods and computers at our disposal, the efficient market hypothesis is once again being debated. At the same time, we are witnessing an unprecedented growth in both existing and new financial markets. These new markets are often in economies which have just recently embraced free market economics; we term these stock markets infant markets. Such stock markets are obviously not efficient in allocating the supply of savings to productive capital. We do not test whether or not these infant markets are informationally efficient, but instead examine whether and how they are becoming more efficient. We propose modelling the excess returns of individual securities using a multi-factor model with time-varying coefficients and generalised auto-regressive conditional heteroskedastic (GARCH) errors. If the markets are becoming more informationally efficient or the agents are learning, we would expect this to manifest itself as the time-varying coefficients becoming more stable as time increases. We test our model using data on four Bulgarian shares. First, we estimate an AR(2) model and a GARCH-M(1,1) model for the shares. Then, we estimated our AR(2) model with time varying coefficients and GARCH type errors. We find varying levels of efficiency and varying speeds of movement towards efficiency within our sample of four shares. 相似文献