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991.
Nassir A. Azimi BA Dr. H. Gilbert Welch MD MPH 《Journal of general internal medicine》1998,13(10):664-669
OBEJCTIVE: Although cost-effectiveness analyses (CEAs) have been advocated as a tool to critically appraise the value of health expenditures, it has been widely hoped that they might also help contain health care costs. To determine how often they discourage additional expenditures, we reviewed the conclusions of recently published CEAs. DATA SOURCES: A search of the Abridged Index Medicus (a subset of MEDLINE designed to afford rapid access to the literature of “immediate interest” to the practicing physician) between 1990 and 1996. STUDY SELECTION: We only included articles that reported an explicit cost-effectiveness (CE) ratio (a cost for some given health effect) in the abstract. DATA ABSTRACTION: From each abstract, we collected the value for the incremental CE ratio and the measure of health effect (life-years, quality-adjusted life-years [QALYs], other). We then categorized the authors’ conclusion into one of three categories: supports strategy requiring additional expenditure, no firm conclusion, and supports low-cost alternative. Finally, we obtained the article and collected information on funding source. DATA SYNTHESIS: Among the 109 eligible articles, the authors’ conclusion supported strategies requiring additional expenditure in 58 (53%) and supported the low-cost alternative in 28 (26%). We then focused on the 65 articles reporting either life-years or QALYs. Cost-effectiveness ratios ranged from $400 to $166,000 (per life-year or QALY) in the 39 articles (60%) in which authors supported additional expenditure, and ranged from $61,500 to $11,600,000 in the 13 articles (20%) in which authors supported the low-cost alternative. Despite identifying similar CE ratios, authors arrived at different conclusions in the overlapping range ($61,500 to $166,000). Of the 10 articles acknowledging industry funding, 9 supported a strategy requiring additional expenditure (p=.01 as compared with those without such funding). CONCLUSIONS: Authors of CEAs are more likely to support strategies requiring additional expenditure than the low-cost alternative. There is no obvious consensus about how small the CE ratio should be to warrant additional expenditure. Finally, concerns about funding source seem to be warranted. 相似文献
992.
993.
Indistinguishable patterns of protooncogene expression in two distinct but closely related tumors: Ewing's sarcoma and neuroepithelioma 总被引:13,自引:0,他引:13
C McKeon C J Thiele R A Ross M Kwan T J Triche J S Miser M A Israel 《Cancer research》1988,48(15):4307-4311
Genetic characterization of human tumors promises new insights of biological importance and clinical relevance. We have found that two solid tumors, peripheral neuroepithelioma and Ewing's sarcoma of bone, which share a common cytogenetic rearrangement, are characterized by an indistinguishable and highly reproducible pattern of protooncogene expression. c-myc, N-myc, c-myb, and c-mil/raf-1 are all expressed at similar levels in these tumors. c-fes and c-sis expression was not detected in any specimens of either tumor. In contrast, the protooncogene c-ets-1, located near the breakpoint of the chromosomal translocation in these tumors, is variable in its expression. We also detected high levels of choline acetyltransferase in these tumors, which suggests a common neural origin. Since it is likely that the clinical behavior and therapeutic responsiveness of tumors relate closely to their biological and genetic features, the pattern of protooncogene expression of individual tumors may provide a novel basis for their characterization. 相似文献
994.
995.
Keith Edwards MA BA RMN Cert Ed RNT 《Journal of advanced nursing》1995,21(2):222-229
This paper is a preliminary study, part of a larger project which is endeavouring to ascertain the views of both users of mental health services and those of mental health branch students as to their perceived and desired role of the mental health nurse Four groups of users (n = 28) and four groups of students (n=44) were contacted, and recorded group discussions took place in gaining qualitative data that would feed into the main body of research The views expressed by both users and students are interestingly convergent, but much concern was expressed as to the needed changes in the provision of the service and the danger for students on qualifying to become quickly incorporated into the prevailing dominant culture 相似文献
996.
997.
998.
C. Gilleard BSc MSc PhD R.G. Mitchell RMN RGN J. Riordan BA 《Journal of advanced nursing》1981,6(2):95-98
The effects of signposts and a ward orientation training programme has been examined with six patients from a male psychogeriatric ward. The results indicate that improved ward orientation can be achieved in such patients, by the use of both signposts themselves and specific training involving the use of signposts. Implications for psychogeriatric rehabilitation nursing are discussed 相似文献
999.
1000.
Duane L. Miller BA 《Digestive diseases and sciences》1971,16(3):247-254
Development of the small intestine is well underway by birth, but it contributes a meager 1.4% (0.07 g) to total body weight. At 25 g (five times the birth weight), it has more than doubled in length (from 20 to 45 cm), is about nine times as heavy, and represents 2.4% (0.6 g) of the body weight. During adolescence, the small intestine undergoes rapid gains until it reaches 75% of its adult length (80 cm), and attains a maximum percentage of nearly 5.0% (3.0 g) of the body weight (60 g). By 125 g, it is nearly fully developed: 95 cm in length, 5 g in weight, and 4% of the body weight. From this point, it only lengthens 10–20 cm and increases 1–2 g in weight. However, the percent of intestine to body weight continues to decrease throughout adulthood to reach only 1.4% (500 g), which was the percentage at birth. Regression formulas show that in the adult rat, the small intestine lengthens 5 cm and gains 0.5 g for each 100-g increase in body weight. Variation within each of the intestinal values measured was considerable but correlated positively with the body weight. Tissue water content was greatest in the duodenum, and varied according to both site and age.Supported in part by Research Grant AM02534 from the National Institutes of Health.The author wishes to acknowledge the valuable guidance of Drs. Harold P. Schedl, MD, PhD, and M. Kabir Younoszai, MD; and the technical assistance of Helen D. Wilson. 相似文献