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排序方式: 共有1693条查询结果,搜索用时 15 毫秒
921.
Thomas S. Huber MD PhD Susan P. McGorray PhD Lori C. Carlton RN Philip B. Irwin PA Richard R. Flug MA RN Timothy C. Flynn MD James M. Seeger MD 《Journal of vascular surgery》1997,25(6)
Purpose: The use of intraoperative autologous transfusion devices expanded during the last decade as a result of the increased awareness of transfusion-associated complications. This study was designed to determine whether routine use of an intraoperative autologous transfusion device (Haemonetics Cell Saver [CS]) during elective infrarenal aortic reconstructions is cost-effective ($50,000/QALYs threshold).Methods: A decision analysis tree was constructed to model all of the complications that are associated with red blood cell replacement during aortic reconstructions for both abdominal aortic aneurysm (AAA) and aortoiliac occlusive disease (AIOD). It was assumed that a unit of CS return (CSR; 250 ml/unit) equaled a unit of packed red blood cells (PRBCs) and that all CS transfusions were necessary. Transfusion requirements (AAA: PRBC = 2.8 ± 3.2 units, CSR = 3.7 ± 3.2 units; AIOD: PRBC = 3.1 ± 3.0 units, CSR = 2.1 ± 1.7 units) were determined from retrospective review of all elective aortic reconstructions (AAA, N = 63; AIOD, N=75) from Jan. 1991 to June 1995 in which the CS was used (82.1% of all reconstructions). Risk of allogenic transfusion-related complications (transfusion reaction, hepatitis B, hepatitis C, human immunodeficiency virus, human T-cell lymphotropic virus types I and II) and their associated treatment costs (expressed in dollars and quality-adjusted life years (QALYs) were obtained from the medical literature, institutional audit, and a consensus of physicians.Results: Routine use of the CS during elective infrarenal aortic reconstructions was not cost-effective in our practice. Use during reconstructions for AAA repairs cost $263.75 but added only 0.00218 QALYs, for a rate of $120,794/QALY. Use during reconstructions for AIOD was even more costly at $356.68 and provided even less benefit at 0.00062 QALYs, for a rate of $578,275/QALY. The sensitivity analyses determined that the routine use of the CS would be cost-effective in our practice only for AAA repairs if the incidence of hepatitis C were tenfold greater than the baseline assumption. The model determined that CS was cost-effective if the CSR exceed 5 units during reconstructions for AAA and 6 units during reconstructions for AIOD.Conclusions: The routine use of the CS during elective infrarenal aortic reconstructions is not cost-effective. The use of the device should be reserved for a select group of aortic reconstructions, including those in which cost-effective salvage volumes are anticipated. Alternatively, the CS should be used as a reservoir and activated as a salvage device if significant bleeding is encountered. (J Vasc Surg 1997;25:984-94.) 相似文献
922.
A non-ionic contrast medium (metrizamide) was compared to an ionic agent (methylglucamine diatrizoate) for pediatric urography. Fifty children were divided into two age groups: under 5, and 5 to 10. In younger children, metrizamide gave more excellent images (19% vs. 0%) and fewer inadequate images (0% vs. 18%) than methylglucamine diatrizoate (p = 0.06). In older children, metrizamide likewise gave more excellent images (44% vs. 14%) and fewer inadequate images (0% vs. 7%). The same pattern was seen when the two groups were combined (excellent, 28% vs. 8%; inadequate, 0% vs. 12%) (p = 0.05). Differences with respect to changes in hematocrit, serum osmolality, serum sodium, and SGOT were statistically significant, but not adverse reactions. In terms of both efficacy and safety, the authors conclude that metrizamide is preferred for pediatric urography. 相似文献
923.
924.
This review summarizes evidence for genes that exist in humans that affect susceptibility to cancer. It is not possible yet to precisely describe the relationship between so-called "cancer gene(s)" and carcinogenesis. Among the questions that remain open is the nature of the events that must occur in individuals with a cancer gene before clinically significant cancer develops. Regardless of the nature of such events, there is evidence that a genetically determined factor can be important in the initial or early steps in malignant transformation of cells. A major challenge in cancer research in the coming years will be the characterization of "cancer gene(s)." Such studies will have profound implications not only for understanding the nature of carcinogenesis, but also for the development of new approaches to detection and treatment of cancer. 相似文献
925.
Lumbar myelography with iohexol and metrizamide: a comparative multicenter prospective study 总被引:2,自引:0,他引:2
Kieffer SA; Binet EF; Davis DO; Gabrielsen TO; Kido DK; Latchaw RE; Turski PA; Shaw DD 《Radiology》1984,151(3):665-670
Diagnostic quality of radiographs and adverse reactions associated with the use of metrizamide and iohexol as contrast agents in lumbar myelography were compared in a prospective randomized double blind study in 350 patients at seven centers. The contrast media were administered in comparable volumes at a concentration of 180 mg I per ml. Overall quality of radiographic visualization was graded good or excellent in 95% of 175 metrizamide studies and in 98% of 175 iohexol studies. Ninety-three patients examined using metrizamide (53%) and 130 patients examined using iohexol (74%) experienced no discomfort during or after myelography. Postmyelographic headache was associated with 38% of metrizamide examinations and 21% of iohexol examinations. Nausea and vomiting were also more common with metrizamide. Five patients examined using metrizamide (3%) experienced transient confusion and disorientation following lumbar myelography. No such reactions were observed following iohexol myelography. 相似文献
926.
With the increasing utilization of mammography, young women under age 30 are being referred for mammographic examination more frequently. A review of the mammograms of 76 patients, aged 18-29 years, was conducted to evaluate the clinical utility of the examination in this age group, for whom the probability of malignancy is quite low and the risk of radiation carcinogenesis may not be negligible. In 74% of patients referred for study of a palpable mass, no mass was evident on mammograms. When a mass was seen, the radiographic features did not influence clinical management. Radiologists should inform their clinical colleagues regarding the risks and limitations of mammography in women under age 30 and encourage more frequent utilization of ancillary diagnostic procedures including sonography and diagnostic aspiration. 相似文献
927.
928.
Okasha M McCarron P McEwen J Smith GD 《Journal of epidemiology and community health》2002,56(10):780-784
STUDY OBJECTIVE: To examine the relation between body mass index (BMI) in young adulthood and subsequent mortality from cancer. DESIGN: Cohort study. SETTING: University of Glasgow student health service. Weight and height were measured by a physician, and used to calculate BMI. PARTICIPANTS: 8335 men and 2340 women who attended the student health service while at university between 1948 and 1968, and who were followed up with the NHS central register. MAIN RESULTS: The main outcome measure was cancer mortality. Three hundred and thirty nine men and 82 women died of cancer during the follow up (mean 41 years). BMI was associated with mortality from all cancers in men and women, although it did not reach conventional statistical significance. The adjusted hazard ratio (HR) (95% CI) per 5 kg/m(2), was 1.22 (0.97 to 1.53) in men and 1.43 (0.95 to 2.16) in women. Two hundred men and 61 women died from cancers not related to smoking. The adjusted HR for mortality from these were 1.36 (1.02 to 1.82) and 1.80 (1.13 to 2.86) respectively. These results are adjusted for height, number of siblings, pulse rate, year of birth, age, smoking, birth order, number of siblings, and age at menarche in women. Site specific analyses, comparing the highest with the lowest quartile of the BMI distribution found increased risks of prostate cancer (n=28) and breast cancer among heavier subjects. No association between BMI and colorectal cancer was found. CONCLUSIONS: BMI in adolescence has lasting implications for risk of cancer mortality in later life. Future research will include measures of BMI throughout the lifecourse, to determine the period of greatest risk of obesity, in terms of cancer mortality. 相似文献
929.
930.
Grace PA 《Irish journal of medical science》2004,173(2):75-77
Background The operation of carotid endarterectomy (CEA) has had an eventful 50 years.
Aim This report reviews the literature comparing the outcome of CEAwith that of medical therapy, angioplasty and stenting.
Methods A review of the published randomised trials.
Results and conclusion After 50 years, CEA is still the gold standard in the management of severe symptomatic carotid artery disease. It is doubtful,
however, that in another 50 years it will continue to retain that pre-eminence. 相似文献