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101.
All physicians who had billed Pennsylvania Blue Shield for at least three intravenous contrast studies during 1989 were surveyed on their use of nonionic versus ionic contrast. This surveyed group represents a diversity of hospital sizes, practice types, and group sizes. Of the 383 physician groups surveyed, responses were obtained from 285. The majority of the responding groups were radiologists (94.0%). Nonionic contrast is utilized in 41.3% of all intravenous studies. Radiologists use nonionic contrast in a much greater proportion than nonradiologists (P < 0.0001), with 17.6% of radiologists utilizing nonionic contrast in all of their patients. Conversely, 75% of nonradiologists utilize ionic contrast in all of their patients. For all physician groups surveyed, 40.3% utilize nonionic for at least 50%, while 27.6% use nonionics for more than 75% of their patients. The routine use of steroid premedication prior to the injection of ionic contrast is not a common practice. The increased utilization of nonionic contrast found in this survey may reflect the cross-section of physicians and practice types surveyed or may represent changing practice patterns among physicians utilizing contrast material.  相似文献   
102.
Compared the performance of autistic and mentally retarded subjects, all of whom had passed a standard first-order test of false belief, on a new second-order belief task 12 autistic and 12 mentally retarded subjects, matched on verbal mental age (assessed by PPVT and a sentence comprehension subtest of the CELF) and full-scale IQ were given two trials of a second-order reasoning task which was significantly shorter and less complex than the standard task used in all previous research. The majority of subjects in both groups passed the new task, and were able to give appropriate justifications to their responses. No group differences were found in performance on the control or test questions. Findings are interpreted as evidence for the role of information processing factors rather than conceptual factors in performance on higher order theory of mind tasks.This study was supported by a grant from the National Institute of Deafness and Other Communication Disorders (1RO1 DC 01234). We thank Jason Barker for his extensive help with this study. We are also very grateful to the schools where the study was conducted including the League School, and the public school systems in the following towns in Massachusetts: Hanover, Hanson, Hingham, Milton, Plymouth, and Rockland. We offer special thanks to Alan Dewey, Mary Dollar, Sandy D'Giacomo, Herman Fishbein, William Griffin, Nancy Kearns, Judy Monahan, Debbie Newhall, Cay Riley, Robert Sherman, and Kathy Staska for their continued support of our research.  相似文献   
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People with AIDS are homeless for a variety of reasons, including financial devastation, rejection based on fear of contagion or fear of the dying process, and homeless-ness prior to a diagnosis of AIDS. The author developed and directed the Shanti AIDS Residence Program in San Francisco, the first program to provide housing for people with AIDS. This model is appropriate for single, independent people able to live cooperatively with others. It provides shared living situations for three to six people per apartment, and office staff physically maintain the houses and assure that the needs for community-based home care and other services are met. Other models are proposed for people who are physically or cognitively dependent (and require physical care or supervision in addition to housing), who are socially unable to live cooperatively with others in an unstrucured living environment (e.g., active substance users or the emotionally disturbed), or who have families (e.g., mothers with dependent children or gay men who live with their lovers).  相似文献   
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The goal of this work was to investigate preference techniques to value potential health gains from treatments of Kaposi sarcoma (KS). The study was designed to take the form of face-to-face interviews with a sample of men with a history of HIV/AIDS ( n=15) or HIV/AIDS and KS ( n=17). The main outcome measure was quality of life (QoL) associated with various KS disease states expressed on a scale from 0 (death) to 1 (perfect health), obtained though time trade-off (TTO) and rating scale techniques. For cutaneous lesions only, the mean TTO preference score value was 0.27. In other words, the men were willing to trade a life expectancy of 5 years for a shorter period (1.4 years) in perfect health. More severe KS health states were rated lower (0.07-0.09). The mean rating scale value for cutaneous lesions only was 0.11 and ranged from -0.10 to -0.04 for the more severe conditions; these values were systematically lower than the TTO ( P=0.014). A large overall potential gain in QoL from treatment (partial response minus stable disease) was found for each condition to be reflected in both the TTO (from 0.31 to 0.55) and the rating scale (from 0.38 to 0.44). Respondents associate KS health states with extremely poor QoL and indicate that large gains are possible through modest treatment effects. While TTO returns higher values than the rating scale, potential gains from treatments were similar. The techniques appear to be suitable for application to QoL and economic evaluation of treatments of KS.  相似文献   
108.
1. The vascular effects of the soluble guanylyl cyclase inhibitor, methylene blue as well as the nitric oxide (NO) synthase inhibitors, NG-nitro-L-arginine (L-NOARG) and diphenyleneiodonium (DPI) were studied in rat isolated aortic rings and conscious, unrestrained rats. 2. Acetylcholine (ACh) and sodium nitroprusside (SNP) caused concentration-dependent relaxation of preconstricted aortic rings. Both methylene blue (1 x 10(-5) M) and L-NOARG (3 x 10(-5) M) abolished ACh-induced relaxation; however, methylene blue but not L-NOARG shifted the concentration-response curve of SNP to the right. 3. In conscious rats, i.v. infusion of methylene blue (1.1 x 10(-5) mol kg-1 min-1), at a concentration which reduced the aortic tissue level of cyclic GMP by 50%, did not significantly alter mean arterial pressure (MAP) and heart rate (HR). In contrast, i.v. bolus injection of L-NOARG (1.5 x 10(-4) mol kg-1) markedly increased MAP and decreased HR. 4. Both ACh and SNP dose-dependently decreased MAP in conscious rats. Methylene blue did not alter the magnitude or duration of ACh- or SNP-induced depressor responses. L-NOARG, on the other hand, significantly though incompletely, reduced the magnitude and duration of the depressor response to ACh but not SNP. The depressor response to ACh or SNP was not altered by pretreatment with indomethacin (1.4 x 10(-5) mol kg-1) or capsaicin (3.3 x 10(-4) mol kg-1). 5. NG-nitro-L-arginine methyl ester (L-NAME) also caused dose-dependent increases in MAP in conscious rats.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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腋淋巴结阴性乳腺癌TGFβl和VEGF表达与预后的相关性研究   总被引:3,自引:0,他引:3  
目的:探讨转化生长因子(TGF)βl和血管内皮生长因子(VEGF)与腋淋巴结阴性乳腺癌(ANNBC)临床病理及强后的关系。方法:应用免疫组化技术(LDP法),对56例随访资料完整的女性ANNBC根治标本进行TGFβl和VEGF检测,分析其表达与ANNBC的预后关系。结果:TGFβl和VEGF、表达与ANNBC的年龄、肿瘤大小、病理类型、组织学分级等一般临床病理因素无相关(P>0.05),而与肿瘤复发、转移密切相关,TGFβl和VEGF阳性表达的肿瘤复发转移率明显高于阴性表达者(P<0.01);TGFβl和VEGF表达呈正相关(P<0.05);Cox比例风险模型多因素分析表明,TGFβl和VEGF是影响ANNBC的预后因子,TGFβl和VEGF表达的ANNBC病人预后差。结论:①测定TGFβl和VEGF的表达,对判断ANNBC病人预后及指导治疗有较大的帮助;②TGFβl和VEGF阳性表达与ANNBC血管生成密切相关,是ANNBC复发、转移的重要促进因素。  相似文献   
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