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排序方式: 共有351条查询结果,搜索用时 15 毫秒
61.
62.
MP Busch ; JJ Korelitz ; SH Kleinman ; SR Lee ; JP AuBuchon ; GB Schreiber 《Transfusion》1995,35(11):903-910
BACKGROUND: Since the mid-1980s, blood banks in the United States have screened donors for elevated alanine aminotransferase (ALT) in an effort to prevent posttransfusion hepatitis. The present study was designed to quantitate the residual value of ALT screening following the implementation of hepatitis C virus (HCV) assays. STUDY DESIGN AND METHODS: Two approaches were used. First, a database of 2.3 million donations made by 586,507 volunteer blood donors between 1991 and 1993 was used to compare the incidence of seroconversion to hepatitis B virus (HBV) and HCV marker positivity in donors with elevated ALT values and with normal ALT values. Second, the duration of ALT elevation prior to HBV and HCV seroconversion was determined from 34 well-documented cases of posttransfusion HBV and HCV; elevated-ALT window periods were multiplied by rates of HBV and HCV incidence in donors to project the yield of ALT screening. Predictive value and cost- effectiveness analyses were also performed to compare the value of ALT screening before and after HCV screening was implemented. RESULTS: Both approaches indicate that ALT testing does not detect HBV in the window phase but does currently identify approximately 3 HCV window-phase donations per 1 million donations; this contrasts with ALT detection of approximately 1800 HCV-infectious units per 1 million donations prior to anti-HCV screening. Currently, only 8 in 10,000 donated units with elevated ALT (negative anti-HCV) are infected with HCV. The cost of continued ALT screening was estimated at $7,931,000 per quality- adjusted year of life saved. CONCLUSION: The yield, predictive value, and cost-effectiveness of ALT screening of blood donors have declined dramatically with the implementation of progressively improved anti-HCV assays. ALT screening of volunteer blood donors should be discontinued. 相似文献
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Noah Lechtzin Charles M Wiener Lora Clawson Matthew C Davidson Fred Anderson Neelam Gowda Gregory B Diette 《Amyotrophic lateral sclerosis and other motor neuron disorders》2004,5(1):9-15
INTRODUCTION: Noninvasive positive pressure ventilation (NIPPV) is associated with improved survival in amyotrophic lateral sclerosis (ALS) and has been widely recommended. The extent of NIPPV use in ALS patients and the factors associated with its use have not been studied. METHODS: A cross-sectional study using the ALS Patient Care Database. Analyses were performed to assess the association of patient and care characteristics with use of ventilatory support. RESULTS: 1458 patients were studied. 15.6% used NIPPV and 2.1% used invasive mechanical ventilation. Patients who used NIPPV were significantly more likely to be male and have higher income than those who did not. They were also more likely to have a gastrostomy tube, lower vital capacity, more severe disease, bulbar involvement and poorer general health status as measured by the SF-12 and Sickness Impact Profile. Multivariate analysis revealed that lower FVC, higher income and use of gastrostomy tube were independently associated with use of NIPPV. CONCLUSIONS: NIPPV is used more than seven times as frequently as invasive ventilation in ALS patients. Patients who use NIPPV have more severe disease than those who do not use any respiratory intervention. Patients with lower income are less likely to use NIPPV, which raises concerns about disparities in the care of patients with ALS. 相似文献
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66.
ED Heegaard H Hale N Clausen A Hornsleth GB Kerndrup 《Acta paediatrica (Oslo, Norway : 1992)》1996,85(3):299-302
It is the purpose of the study to report the frequency of parvovirus in children with a diagnosis of Diamond-Blackfan anaemia and to discuss the possible aetiological role of parvovirus in Diamond-Blackfan anaemia. We found parvovirus DNA in 3 of 11 bone marrow smears. Giant pronormoblasts showed low sensitivity (33%) and poor specificity (75%). The presence of giant pronormoblasts was associated with a very high myeloid: erythroid ratio, and may not be specific for parvovirus infection, but a feature of severely suppressed erythropoiesis. The three parvovirus-positive patients were the only children who experienced a remission, and who are free of medication. The seven surviving parvovirus-negative patients are all currently on steroid treatment. 相似文献
67.
KGF-transfected cells can stimulate growth and proliferation of human cultured keratinocytes in vitro 总被引:1,自引:0,他引:1
Objective: To establish two stably KGF-transfected, immortalized cell lines. Methods: HaCaT-keratinocytes and KMST-6-fibroblasts were transfected by liposome mediated gene transfer. Transfection effectivity, gene integration and configuration of the transgenic protein were investigated by ELISA, DANN-PCR and β-Gal-staining. Results: Most effective GF producing clones were tested by a colorimetric XTT-test. Conclusion: This is a significant acceleration of cell proliferation and mitosis of human keratinocytes in an Air Liquid Interface (ALI) test system. 相似文献
68.
69.
Unilateral hypertrophic osteoarthropathy in a patient with an infected axillary-axillary bypass graft 总被引:1,自引:0,他引:1
Hypertrophic osteoarthropathy (HO) is a specific clinicoradiologic entity, the most common cause of which is the presence of pulmonary lesions. Eight cases of aortic graft infection and aortoenteric fistulae in association with HO have been recognized. A case of an infected axillary-axillary graft presenting as unilateral HO of the upper limb is reported, and its unusual features are used to postulate a mechanism underlying HO. 相似文献
70.
Reznik RB Goldstein GB I. Ring 《Australian and New Zealand journal of public health》1986,10(2):197-204
Incidence rates and death rates for acute myocardial infarction (AMI) were compared in New South Wales and Queensland to investigate whether changes in death rates were correlated with changes in incidence rates. The incidence of AMI was 1.9 per cent higher for males and 14.9 per cent lower for females in Queensland than in New South Wales. Differences in age-specific incidence rates paralleled differences in age-specific death rates, suggesting that observed changes in death rates may reflect changes in incidence, rather than case-fatality. Risk factor patterns are broadly similar between the two states, apart from the prevalence of cigarette smoking which, like the incidence of AMI, is higher in males and lower in females in Queensland. 相似文献