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91.
BACKGROUND: Although HIV testing is recommended for persons with hepatitis C virus (HCV) infection who are at risk for HIV, little is known about HIV testing in this population. METHODS: Data were prospectively collected in 4364 HCV-infected patients at 24 Veterans Affairs medical centers across the United States, including demographics, risk factors for HIV infection, and self-reported information on HIV testing. RESULTS: Overall, 76.8% had been tested for HIV at least once, 14.8% were never tested, 6.6% did not know if they were tested, and 1.8% declined to answer. Multivariable analysis identified injection drug use, needlestick injury, sex with a same-sex partner, a greater number of lifetime sexual partners, and sex with an injection drug user as factors that were independently associated with HIV testing. At least one risk factor for HIV infection was present in 84.5% of the 646 patients who were never HIV tested. Among the 3350 subjects who were tested for HIV, 8.4% were positive, 88.3% were negative, 2.4% did not know the results of their test, and 0.9% declined to answer. Multivariable analysis identified African American and Hispanic race/ethnicity, income < or = 10,000 dollars, sex with a same-sex partner, and sex with an injection drug user as the only variables that were independently associated with HIV seropositivity. CONCLUSIONS: Although a substantial proportion of HCV-infected patients have been tested for HIV, missed opportunities for early diagnosis of HIV infection exist. Public health strategies to improve HIV testing among patients with chronic HCV infection are needed.  相似文献   
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Even if neoplastic cells express tumor associated antigens they still may fail to function as antigen presenting cells (APC) if they lack expression of one or more molecules critical for the induction of productive immunity. These cellular defects can be repaired by physiologic activation, transfection, or fusion of tumor cells with professional APC. Although such defects can be repaired, antitumor specific T cells may still fail to respond in vivo if they may have been tolerized. Here, human pre-B cell acute lymphoblastic leukemia (pre-B ALL) was used as a model to determine if primary human tumor cells can function as alloantigen presenting cells (alloAPC) or alternatively whether they induce anergy. In the present report, we show that pre-B cell ALL express alloantigen and adhesion molecules but uniformly lack B7-1 (CD80) and only a subset express B7-2 (CD86). Pre-B ALL cells are inefficient or ineffective alloAPC and those cases that lack expression of B7-1 and B7-2 also induce alloantigen specific T- cell unresponsiveness. Under these circumstances, T-cell unresponsiveness could be prevented by physiologic activation of tumor cells via CD40, cross-linking CD28, or signaling through the common gamma chain of the interleukin-2 receptor on T cells. Taken together, these results suggest that pre-B ALL may be incapable of inducing clinically significant T-cell-mediated antileukemia responses. This defect may be not only due to their inability to function as APC, but also due to their potential to induce tolerance. Attempts to induce clinically significant antitumor immune responses may then require not only mechanisms to repair the antigen presenting capacity of the tumor cells, but also reversal of tolerance.  相似文献   
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This article reports the first case of immune hemolytic anemia possibly associated with the ingestion of suprofen. The patient suffered from massive hemoglobinuria and acute renal failure. Serologic studies of the patient's serum revealed suprofen-dependent red cell antibodies. However, tolmetin-dependent antibodies were also found in the serum, showing the same properties as the suprofen antibodies and an even higher titer. The patient not only had drug-dependent antibodies in the serum, but also had developed autoantibodies, a phenomenon that has been described for several other drugs. The working mechanism by which suprofen and tolmetin caused immune hemolysis had properties of both the immune complex model and the induction of autoimmunity. Although it was unclear whether the immune hemolytic anemia was the result of suprofen, tolmetin, or cross-reacting antibodies, we feel that suprofen should be added to the list of nonsteroidal anti-inflammatory drugs associated with a positive direct antiglobulin test.  相似文献   
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Hepatobiliary complications in chronic pancreatitis.   总被引:3,自引:0,他引:3       下载免费PDF全文
Thirty nine patients undergoing surgery for chronic pancreatitis were investigated for evidence of hepatobiliary disease. In addition to pre-operative assessment by liver function tests, ultrasound, ERCP (in 33) and percutaneous transhepatic cholangiography (in five), all had peroperative liver biopsy. Common bile duct stenosis was diagnosed in 16 (62%) of the 26 patients with successful cholangiography. Features of extrahepatic biliary obstruction were found on biopsy in 11 patients, three of whom showed features of secondary sclerosing cholangitis. No patients had secondary biliary cirrhosis. Three had parenchymal liver disease (cirrhosis, resolving hepatitis and alcoholic hepatitis respectively) and two others had features suggestive of previous alcohol-induced injury. Five (83%) of the patients with clinical jaundice had biopsy features of extrahepatic biliary obstruction, as did eight (67%) with alkaline phosphatase above twice normal and seven (44%) with radiological common bile duct stenosis. Neither alkaline phosphatase rise, nor common bile duct stenosis alone or in combination, were a reliable indication of the need for biliary enteric bypass surgery. Pre-operative liver biopsy may be a valuable adjunct in the assessment of such patients.  相似文献   
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Purpose: Tactile impairments affect over 77% of children with unilateral cerebral palsy (CP). This study aimed to examine the current practices of pediatric therapists in relation to tactile assessment and the barriers to carrying out tactile assessment in children with CP.

Method: The study was in two parts. In part one, pediatric therapists (n?=?35) completed a questionnaire detailing their current knowledge and the use of tactile assessments in children. In part two, therapists (n?=?12) completed a questionnaire based on the Theoretical Domains Framework examining the barriers and facilitators to completing tactile assessments in clinical practice.

Results: Most therapists (over 90%) carry out tactile assessments in the minority (less than 25%) of children with CP that they treat. Therapists reported the need for improved knowledge/skills (n?=?24) and confidence (n?=?19) in carrying out tactile assessments, alongside the provision of necessary equipment (n?=?17). Qualitative reports also suggested that organizational assessment guidelines and templates may facilitate the implementation of tactile assessment.

Conclusions: A multi-faceted knowledge translation strategy to address the barriers to tactile assessment among pediatric therapists needs to be developed.
  • Implications for rehabilitation
  • Pediatric occupational therapists and physiotherapists may not be completing tactile assessments according to current evidence-based recommendations.

  • Therapists identified five main barriers, including a lack of knowledge, skills, belief in their capabilities (confidence), behavioral regulation (organizational procedures), and environmental context (e.g., equipment).

  • Therapists recommended several potential facilitators, including access to necessary equipment, procedures, record sheets, training in tactile assessments, and research supporting related interventions.

  • Service providers are encouraged to develop multi-faceted knowledge translation strategies that address these barriers and maximize facilitators.

  相似文献   
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