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991.
992.
Nineteen semistructured interviews with HIV-positive methamphetamine-using gay, bisexual, or other MSM were analyzed qualitatively and using Critical Incident Measure (CIM). Among those who reported successful disclosure, themes regarding disclosure strategies and precontact disclosure emerged. Although few men spontaneously discussed the association between methamphetamine and disclosure, those who did reported less inclination to ascertain partner serostatus while under the influence. Men who reported disclosure to an HIV-seroconcordant partner were more likely to report not exchanging semen in this encounter compared with nondisclosers, whereas condom nonuse emerged as a theme across disclosure groups. Most of those who reported nondisclosure described their most recent encounter under the influence as occurring in the context of a public sex environment and/or with multiple partners. Understanding the interaction between methamphetamine use and serostatus disclosure practices, particularly among HIV-positive men, and how this interaction impacts sexual risk-taking has important implications for HIV prevention work.  相似文献   
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BACKGROUND: Transfusion-related acute lung injury (TRALI) is clinically similar to the adult respiratory distress syndrome (ARDS) and has been linked to the transfusion of leukocyte antibodies in blood components. Animal model have implicated neutrophil (PMN)-priming agents in ARDS; however, two agents were required. Previous studies showed the generation of PMN-priming agents during blood storage. Thus the association of PMN-priming agents with TRALI was examined. STUDY DESIGN AND METHODS: Ten patients with TRALI and 10 with febrile or urticarial reactions (control group) were evaluated. The presence of PMN-priming activity was tested in the patients' pretransfusion and posttransfusion blood samples by incubating PMNs with these samples followed by activation of the respiratory burst. Plasma lipids were separated by normal-phase high-performance liquid chromatography (HPLC), and the priming activity was evaluated. The presence of leukocyte antibodies was determined in the blood donors and patients with TRALI. RESULTS: Significantly more PMN-priming activity was present in the posttransfusion sera (11.4 +/? 1.8 nmol superoxide anion/min, mean +/? SEM; n=10) and plasma of patients with TRALI than in their pretransfusion sera (6.5 +/? 1.5: n=10) or in the pretransfusion and posttransfusion sera (5.1 +/? 1.3, n=10; and 4.5 +/? 1.4, n=10, respectively) and from the controls (p < 0.05). HPLC separation of lipids demonstrated that three active species were present in the posttransfusion plasma samples of TRALI patients. All the patients with TRALI had underlying clinical factors, such as infection, cytokine administration, recent surgery, or massive transfusion, while only 2 of 10 control patients had these clinical conditions. None of the donors had significant titers of HLA or HLA-DR antibodies; however, 50 percent had weak positivity for granulocyte antibodies. CONCLUSION: TRALI is the result of two clinical events, the first being a predisposing clinical condition and the second being the transfusion of biologically active lipids in stored blood.  相似文献   
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Changing transfusion practices in hip and knee arthroplasty   总被引:3,自引:1,他引:3  
BACKGROUND: This study was designed to examine changes in perioperative transfusion practices after the introduction of autologous blood conservation strategies into routine clinical practice. STUDY DESIGN AND METHODS: The existing medical records of all patients undergoing total hip or knee arthroplasty at Mayo Clinic in Rochester, MN, who resided in Olmsted County, were reviewed over three periods: 1981–82 (232 procedures), 1987–88 (269 procedures), and 1993–94 (398 procedures). RESULTS: The proportion of patients receiving any perioperative red cell (RBC) units significantly decreased (from 85% in 1981–82 to 65% in 1993–94). The timing of transfusion also changed; the proportion of RBC units transfused in the preoperative or intraoperative periods decreased from 68 percent in 1981–82 to 38 percent in 1993–94, with the balance of RBC units transfused in the postoperative period. Although the number of RBC units utilized per procedure in the intraoperative period significantly decreased, the number of RBC units transfused in the postoperative period significantly increased (from 0.6 +/− 1.0 to 1.1 +/− 1.4 units per procedure in 1981–82 and 1993–94, respectively, p < 0.05). CONCLUSION: Although blood conservation strategies have been successful in reducing RBC transfusion intraoperatively, avoidance of intraoperative transfusion may in some cases postpone, rather than prevent, transfusion.  相似文献   
997.
BACKGROUND: Most enzyme immunoassay-reactive specimens producing indeterminate Western blot results belong to individuals who are not infected with human immunodeficiency virus type 1 (HIV-1). However, a small percentage may correspond to early seroconversion or advanced disease, at which stage partial reactivity on Western blot may be observed. STUDY DESIGN AND METHODS: To determine the utility of HIV-1 p24 antigen and cell-free RNA detection for the resolution of Western blot-indeterminate serologic results, several types of enzyme immunoassay-positive, sero-indeterminate specimens were analyzed. Samples were obtained from infected individuals at the time of seroconversion (n = 20), from patients with AIDS (n = 2), as specimens from clinical samples obtained for diagnostic testing (n = 57), from blood donors producing persistent indeterminate results (n = 47), and from random blood donors (n = 72). RESULTS: HIV-1 p24 antigen was detected in 10 of 20 specimens collected from 9 of 12 individuals who seroconverted and in 2 of 2 AIDS patients. HIV-1 plasma RNA was positive in 22 of 22 samples from those 14 individuals. All of 57 diagnostic specimens and 47 samples obtained from persistently indeterminate donors were negative for HIV-1 p24 antigen and plasma HIV- 1 RNA. One of 72 blood donor specimens was positive for HIV-1 plasma RNA and had borderline reactivity for p24 antigen. CONCLUSION: The detection of plasma RNA appears to be sensitive and specific; negative test results may be used to identify false-positive serologic reactions. The detection of p24 antigen and plasma RNA can also be used to confirm HIV-1 infection in persons with indeterminate serologic results associated with early seroconversion or late-stage disease.  相似文献   
998.
Introduction: We investigated the effect of stimulation intensity (in percent of maximal tolerated stimulation current, mTSC), frequency, and impulse width on muscle fatigue. Methods: Using a randomized crossover design, 6 parameter combinations (80% mTSC, 80 Hz , 400 μs; 60% mTSC, 80 Hz , 400 μs; 80% mTSC, 20 Hz , 400 μs; 60% mTSC, 20 Hz , 400 μs; 80% mTSC, 80 Hz , 150 μs; 60% mTSC, 80 Hz , 150 μs) were tested in both legs of 13 athletic men (age 26 ± 2.3). The slope of the linear regression line over all tetani (FIS) and the number of tetani whose force was above 50% of the initial tetanus (FIN) were used to quantify fatigue. Results: FIS and FIN were significantly lower in high‐frequency protocols. No effects on FIS and FIN were found for intensity and impulse width. Conclusions: Stimulation frequency, but not impulse width or intensity, affected fatigue kinetics. Muscle Nerve 53 : 608–616, 2016  相似文献   
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Self-expandable oesophageal stents are being increasingly used in the management of malignant oesophageal strictures. Most benign peptic oesophageal strictures can be successfully managed using endoscopic oesophageal dilatation combined with long-term Proton pump inhibition therapy. Although endoscopic oesophageal dilatation can be performed on an outpatient basis, it often requires repeated hospital visits. There is a small risk of oesophageal perforation, while cardiorespiratory complications may be encountered during the use of intravenous sedation in an elderly population. The use of self-expandable Strecker stents in three elderly patients with benign peptic oesophageal strictures is described.  相似文献   
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