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261.
262.

Introduction

Most hospitals are faced with reduced personnel, resources, and provider fatigue or shift changes when day turns to night. For these reasons, some have suggested that diaphyseal femur fractures should be fixed during the daytime. The purpose of this study is to determine whether the time of surgery affects the post-operative difference in femoral version (DFV) and femoral length (DFL) between the fixed and uninjured sides following intramedullary nailing (IMN).

Materials and methods

Over a 10-year period, 340 patients underwent IMN of a diaphyseal femur fracture (AO types 32-A to C) with a post-operative computed tomography scanogram for version measurement. Demographic and surgical data, including time operated was collected. “Daytime” was defined as 7:00 AM to 6:59 PM, while the remainder of the clock was “nighttime”. Additionally, the night hours were split into 3 consecutive 4-h categories for further analysis. Stepwise, multivariate regressions were used to evaluate any effect of time of surgery on post-operative DFV or DFL. Other variables included in these statistical models were age, sex, mechanism of injury, open vs. closed fracture, trauma vs. non-trauma surgeon, and AO and Winquist classifications.

Results

Overall, 22.4% (76/340) of all fractures were fixed at night. The mean post-operative DFV and DFL from the uninjured side in these patients was 8.9° and 4.1 mm, respectively, compared to 9.0° and 4.8 mm in those treated during the daytime. This difference was not statistically significant when accounting for other factors (p > 0.05). There was no statistically significant difference in patients with >10 mm limb length discrepancy or >15 degrees DFV (p = 1.0 for both).

Conclusion

The time of day at which diaphyseal femur fractures are treated does not have an impact on post-operative femoral version or length. While certain other injuries may be better handled during daytime hours, acceptable IMN of mid-shaft femur fractures may be achieved during all hours at a level 1 trauma centre.  相似文献   
263.
Hepatitis C in patients undergoing liver transplantation.   总被引:3,自引:0,他引:3  
OBJECTIVE: To determine the prevalence of antibodies to hepatitis C virus (anti-HCV) among patients undergoing liver transplantation and the relation between anti-HCV and post-transplant hepatitis. DESIGN: Retrospective cohort. PATIENTS: Serum samples from 128 patients who underwent liver transplantation. Sixty-six patients who had 6 months of follow-up and for whom both pretransplant and post-transplant serum samples were available were included in a study to asses the relation between anti-HCV and post-transplant hepatitis. MEASUREMENTS: Sera were tested for anti-HCV using an enzyme-linked immunosorbent assay (ELISA) and, if positive, two confirmatory tests were done. Patients had a biopsy every week until two specimens showed no abnormal findings. MAIN RESULTS: Only patients with chronic non-A, non-B hepatitis (15 of 30; 50%), alcoholic cirrhosis (7 of 19; 37%), and chronic hepatitis B infection (3 of 11; 27%) were anti-HCV positive. No patient with another form of chronic liver disease or with acute liver failure due to non-A, non-B hepatitis was anti-HCV positive. After transplantation, loss of anti-HCV was frequent and acquisition rare. Hepatitis developed in the graft in 17% of patients, but the incidence was similar among anti-HCV negative and anti-HCV-positive patients. CONCLUSIONS: Hepatitis C virus is a common cause of chronic liver disease in patients requiring liver transplantation, but anti-HCV is rarely found in patients with acute liver failure. Previous HCV infection, based on detection of anti-HCV, is not an independent risk factor for post-transplant hepatitis.  相似文献   
264.
OBJECTIVE: To assess the incidence of human immunodeficiency virus type 1(HIV-1) transmission by antibody (anti-HIV-1)-positive blood components, and to determine the immunologic and clinical course in HIV-1-infected recipients. DESIGN AND SUBJECTS: We retrospectively tested approximately 200,000 donor blood component specimens stored in late 1984 and 1985 for anti-HIV-1, and we contacted recipients of positive specimens to determine their serologic status. They were compared with both recipients of HIV-1-negative transfusions and healthy (untransfused) controls. Subjects were seen at 3- to 6-month intervals for up to 4 years for clinical and immunologic evaluations. MEASUREMENTS AND MAIN RESULTS: Of 133 recipients, 9 had other possible exposures. Excluding these cases, 111 of 124 (89.5%) were anti-HIV-1-positive (95% CI, 84.1% to 94.5%). The recipient's sex, age, underlying condition, and type of component did not influence infection rates. The cumulative risk for developing the acquired immunodeficiency syndrome (AIDS) within 38 months after transfusion was 13% (CI, 7.5% to 21.6%). At 36 +/- 3 months after the index transfusion, seropositive recipients had lower counts of CD2+CDw26+, CD4+, CD4+CD29+, and CD4+CD45RA+subsets and more CD8+I2+ lymphocytes than did recipients of anti-HIV-1-negative transfusions. The CD4+ and CD2+CDw26+subsets changed the most rapidly. The absolute CD8+ count remained normal. CONCLUSIONS: Transfusion of anti-HIV-1-positive blood infected 90% of recipients. The rate of progression to AIDS within the first 38 months after infection was similar to that reported for homosexual men and hemophiliacs. Although most lymphocyte subset counts changed over time, CD8+ counts were constant.  相似文献   
265.
Traditional methods used in identifying mycobacteria such as acid-fast bacillus stains and culture are often time-consuming, insensitive and non-specific. The isolation of DNA probes, coupled to a non-radioactive, e.g. biotin-based detection system, have the potential to foster the development of clinical assays for Mycobacterium tuberculosis and mycobacteria other than tuberculosis (MOTT) that are rapid, sensitive and specific. To this end, we have isolated two different probes: one which is specific for the Mtb complex and one which recognizes all other potentially pathogenic mycobacteria. The use of these probes in combination should allow the detection and differentiation of M. tuberculosis from MOTT. To isolate the first probe, we prepared a library of M. tuberculosis DNA fragments in a lambda EMBL phage vector. Recombinant phage were screened by plaque-lift hybridization procedures using nick-translated mycobacterial genomic DNA to identify sequences specific to the Mtb complex. Inserts from candidate recombinant phage were purified, nick-translated and hybridized against a wide variety of filter-bound mycobacterial and non-mycobacterial DNAs. Two clones were identified which hybridized to the closely related M. tuberculosis, M. bovis and M. microti but not to other species of mycobacteria. The second probe was isolated by preparing a library of M. malmoense DNA fragments in lambda EMBL and screening by plaque-lift hybridization. One clone was identified which, in addition to recognizing members of the Mtb complex, also hybridized to M. intracellulare, M. malmoense, M. scrofulaceum, M. simiae, M. xenopi, M. avium, M. szulgai, M. kansasii and M. haemophilum. None of the three clones hybridized to DNA from non-mycobacterial species.  相似文献   
266.
We interviewed 51 blood donors in four major US metropolitan areas subsequently found to have had antibodies to human T-cell lymphotropic virus (anti-HTLV) in late 1984-early 1985. Sixteen donors (31%) reported that they or a sexual contact had a history of blood transfusion. Twelve donors (24%) reported that they or a sexual contact used intravenous drugs. Ten donors (20%) were blacks born in the southeastern US. Four of the male donors (15%) reported homosexual contact. The most common characteristic was an association with Japan or the Caribbean basin (61%). These results show a broader variation of epidemiologic backgrounds than anticipated.  相似文献   
267.
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