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排序方式: 共有1084条查询结果,搜索用时 312 毫秒
91.
Pulmonary embolism after hip or knee replacement: postoperative changes on pulmonary scintigrams in asymptomatic patients 总被引:1,自引:0,他引:1
Foley M; Maslack MM; Rothman RH; Casey MP; Lugano EM; Parry CE; Balderston RA; Booth RE Jr 《Radiology》1989,172(2):481-485
Serial pulmonary imaging has proved to be effective in the evaluation of patients undergoing total joint arthroplasty. A clinical dilemma arises in asymptomatic patients whose postoperative pulmonary images differ from the preoperative images. The authors prospectively evaluated 403 patients with serial imaging to determine the significance of changed postoperative images in asymptomatic patients undergoing total hip or knee arthroplasty. Twenty-two (5.5%) patients had significant changes on postoperative images. Seventeen were asymptomatic; all but one underwent pulmonary angiography. Documented pulmonary emboli were demonstrated in 100% of patients whose postoperative images changed to indicate a high probability of pulmonary embolism, 71% whose images changed to a moderate probability, and 0% whose images changed to indeterminate probability. Overall, pulmonary emboli occurred in 76% of all asymptomatic patients with significantly change postoperative images. Asymptomatic pulmonary embolism is a significant occurrence after total hip or knee repair, and a changed lung scan with appropriate clinical evaluation is an accurate indicator of pulmonary emboli in asymptomatic postarthroplasty patients. 相似文献
92.
Liu J Zheng BS Aposhian HV Zhou YS Chen ML Zhang AH Waalkes MP. 《Journal of the peripheral nervous system : JPNS》2002,7(3):208-208
Optimization of a previously disclosed sorbitol dehydrogenase inhibitor (SDI, II) for potency and duration of action was achieved by replacing the metabolically labile N,N-dimethylsulfamoyl group with a variety of heterocycles. Specifically, this effort led to a series of novel, in vitro potent SDIs with longer serum half-lives and acceptable in vivo activity in acutely diabetic rats (e.g., 62, 67, and 69). However, the desired in vivo potency in chronically diabetic rats, ED90 less than or equal to 5 mg/kg/day, was achieved only through further modification of the piperazine linker. Several members of this family, including 86, showed better than the targeted potency with ED90 values of 1-2 mg/kg/day. Compound 86 was further profiled and found to be a selective inhibitor of sorbitol dehydrogenase, with excellent pharmacodynamic/pharmacokinetic properties, demonstrating normalization of sciatic nerve fructose in a chronically diabetic rat model for approximately 17 h, when administered orally at a single dose of 2 mg/kg/day. 相似文献
93.
Let''s look at human immunodeficiency virus look-back before leaping into hepatitis C virus look-back 总被引:1,自引:0,他引:1
MP Busch 《Transfusion》1991,31(7):655-661
94.
J. M. Fletcher R. Couper D. Moore R. Coxon S. Dorney 《Journal of inherited metabolic disease》1999,22(5):581-586
Background: Arginosuccinic acid synthetase (ASA) (EC 6.3.4.5) deficiency (citrullinaemia) (McKusick 215700) is a well-recognized cause of neonatal hyperammonaemic coma with poor long-term intellectual function, despite good medical management.Methods: Cadaveric hepatic transplantation was performed in a 12-year-old boy with citrullinaemia under poor biochemical control. Subsequent development of fulminant hepatic failure necessitated a second cadaveric transplant. Psychometric assessments before and after transplantation were performed using a variety of age-appropriate tests.Results: Normalization of plasma ammonium in our patient post transplantation has resulted in dramatic improvement in mental functioning and well-being and he now enjoys a normal diet. Psychometric assessment confirmed decline in his abilities prior to transplantation with particular post-transplantation improvement in perceptual organization and visuospatial abilities; these did not, however, return to normal. His family report considerable reduction in stress associated with the unpredictable nature of previous hyperammonaemic crises and recurrent hospitalization.Conclusions: Liver transplantation should be considered as an early therapeutic option in children with citrullinaemia to prevent ongoing cerebral insult associated with hyperammonaemia. 相似文献
95.
OBJECTIVES: To explore differences in views concerning adjunctive medications and theoretical orientation among Canadian practitioners from different professional backgrounds who treat alcoholism. METHODS: A survey of clinicians from different disciplines was conducted by mail. The response rate was 56%: 95 drug and alcohol counsellors, 46 social workers, 81 nonpsychiatrist addiction physicians, and 74 addiction psychiatrists. The number of items in the questionnaire was reduced using principal component analysis. Group differences were explored using analysis of variance with Bonferroni correction and Scheffé's posthoc comparisons. RESULTS: Physicians and nonphysicians differed in their views on the utility of medications in treating alcohol problems, the disease concept of alcohol problems, and the classification of alcohol abuse or dependence as psychiatric conditions. No group differences emerged on views regarding cognitive-behavioural treatment, pharmacological-only interventions, combined treatment, and recovery without treatment. Psychopathology in the alcoholic was significantly more likely to be considered as secondary to the use of alcohol by nonpsychiatrist physicians. Nonphysician practitioners viewed alcoholic behaviour as self-medication. CONCLUSIONS: Groups differed on questionnaire items concerning medication use and the disease concept of alcoholism. Agreement on several areas may facilitate bridging the gap across disciplines. The implications of these results are discussed. 相似文献
96.
Rubin JI; Arger PH; Pollack HM; Banner MP; Coleman BG; Mintz MC; VanArsdalen KN 《Radiology》1987,162(1):21
97.
JJ Korelitz ; AE Williams ; MP Busch ; TF Zuck ; HE Ownby ; LJ Matijas ; DJ Wright 《Transfusion》1994,34(10):870-876
BACKGROUND: Most blood centers utilize a confidential unit exclusion (CUE) process, intended to reduce the risk of transfusion-associated infectious diseases by allowing high-risk donors confidentially to exclude their blood from use for transfusion. The effectiveness of this method remains controversial. STUDY DESIGN AND METHODS: Confirmatory or supplemental test results for antibodies to human immunodeficiency virus, human T-lymphotropic virus type I, and hepatitis C virus, as well as hepatitis B surface antigen and syphilis and screening test results for antibodies to hepatitis B core (antigen) and alanine aminotransferase levels were obtained for approximately 1.8 million units donated during 1991 and 1992 at five blood centers within the United States. The prevalences of these infectious disease markers in units that the donors confidentially excluded (CUE+) and units that the donors did not exclude (CUE-) were calculated and examined within demographic subgroups. RESULTS: Units that were CUE+ were 8 to 41 times more likely to be seropositive for antibodies to human immunodeficiency virus and hepatitis C virus, hepatitis B surface antigen, and syphilis and three to four times more likely to react for antibody to hepatitis B core (antigen) or to have elevated alanine aminotransferase levels than units that were CUE- (p < 0.001). The positive predictive value of CUE (the percentage of CUE+ units that were confirmed seropositive for any marker) was 3.5 percent, and the sensitivity of CUE (the percentage of confirmed-seropositive units that were CUE+) was 2.3 percent. CONCLUSION: The current CUE process has low sensitivity and apparently low positive predictive value, and in many cases, it appeared that donors misunderstood it. Yet, CUE was not a “random process,” as CUE+ units were more likely to be seropositive for any infectious disease marker than CUE- units. This suggests that efforts to improve the CUE system may be warranted. As risk factors for transfusion-transmitted infection become more difficult to identify by history-based screening, however, such efforts may have limited effect. 相似文献
98.
The Viral Activation Transfusion Study (VATS): rationale, objectives, and design overview 总被引:1,自引:0,他引:1
99.
Maat M Buysse CM Emonts M Spanjaard L Joosten KF de Groot R Hazelzet JA 《Critical care (London, England)》2007,11(5):R112
Background
To gain insight into factors that might affect results of future case-control studies, we performed an analysis of children with sepsis and purpura admitted to the paediatric intensive care unit (PICU) of Erasmus MC-Sophia Children's Hospital (Rotterdam, The Netherlands). 相似文献100.
BACKGROUND: Concern over the theoretical possibility of disease transmission via blood from donors who develop Creutzfeldt-Jakob disease has led to proposals to exclude older individuals from donating plasma for further manufacture into pooled plasma donations. The impact of extending this age-deferral policy to blood donors was examined with respect to the risk for known transmissible viruses. STUDY DESIGN AND METHODS: Demographic characteristics and confirmed prevalence rates (/10(5) first-time donations) and incidence rates (/10(5) person-years for repeat donors) for viral markers were compared for donors < 50 years old (n = 1,259,805 [85%]) and > or = 50 years old (n = 219,856 [15%]) and for donors < 60 years old (n = 1,409,176 [95%]) and > or = 60 years old (n = 70,485 [5%]). Incidence rates were combined with infectious window-period estimates for each virus, to calculate the risk of virus transmission per 10(6) donations. RESULTS: Unadjusted prevalence rates were significantly greater for younger than for older donor groups for human immunodeficiency virus (HIV), hepatitis B surface antigen (HBsAg), and hepatitis C virus (HCV) (p < or = 0.05). Incidence rates (and transmission risk estimates) for HBsAg were significantly higher in the < 50 donor group than in the > or = 50 group (p < or = 0.05), and those for HIV, human T-lymphotropic virus, and HCV were not significantly higher (p > 0.05). Blanket removal of donors over the age of 50 would potentially lead to the following significant increases in the risk of infected units: HIV, 12 percent; HCV, 21 percent; and hepatitis B virus (HBsAg), 22 percent. CONCLUSION: Removal of donors over the age of 60 would not significantly affect the risk of infected units. Deferral of donors > or = 50 years of age from whole-blood donations for unfounded concerns about Creutzfeldt-Jakob disease could have adverse effects on both blood availability and safety. 相似文献