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Epstein-Barr virus (EBV) was inoculated into two species of marmosets. Successful infection was established in the majority of the animals of one species, Callithrix jacchus, as evidenced by the development of high, persistent levels of antibody against virus-specific capsid and early nonstructural proteins. Antibodies also were produced against the major membrane antigen and, in some animals, against EBV nuclear antigen (EBNA) 2 but not against EBNA 1. This is the antibody profile normally noted in individuals with chronic infectious mononucleosis (IM). EBV-induced lymphoproliferation was not seen, and EBV-specific proteins were not detected in the peripheral blood lymphocytes of infected animals. Hence, EBV infection in C. jacchus apparently does not generally include extensive B-cell involvement. However, the marmosets clearly are useful as a model for EBV primary infection and also possibly for chronic IM.  相似文献   
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Hydroquinidine is a structural analogue of quinidine. It is used in the treatment and prevention of cardiac arrhythmias and necessitates serum monitoring. Fluorescence polarization immunoassay (FPIA) of quinidine has been proposed and we have tested the performance of this assay for hydroquinidine using its cross-reaction with quinidine. Tracer (quinidine labelled with fluorescein) and anti-serum were purchased from Abbott S.A. Standard curves were obtained using specifically prepared hydroquinidine calibrators and within-run and run-to-run precision values (expressed as relative standard deviation) (RSD) lower than 5.3% (n = 10). In order to evaluate specificity of this assay in the clinical situation, FPIA and liquid chromatography results were compared.  相似文献   
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CD4+ T lymphocytes are currently the most common surrogate marker indicating disease progression in individuals infected with human immunodeficiency virus (HIV). Since the cost of enumerating lymphocyte phenotypes is quite high, an inexpensive bead assay analyzed by light microscopy (cytosphere assay; Coulter Corporation, Hialeah, Fla.) was developed as an alternative method for counting CD4+ and CD8+ T lymphocytes. To evaluate the reliability of the cytosphere assay, heparinized blood was collected from 117 HIV-infected individuals and tested for both CD4+ and CD8+ lymphocytes by flow cytometry and the cytosphere assay. The Pearson correlation coefficient of the cytosphere assay compared with that of flow cytometry for CD4+ T lymphocytes was 0.93, with mean values +/- standard deviations of 534 +/- 509 by flow cytometry and 499 +/- 477 by the cytosphere assay. The correlation coefficient for CD8+ T lymphocytes was 0.86, with mean values of 831 +/- 543 by flow cytometry and 746 +/- 472 by the cytosphere assay. The sensitivity and specificity of the cytosphere assay in determining absolute CD4+ T-lymphocyte counts of less than 200/microliters were 97.6 and 94.7%, respectively. The positive predictive value was 90.9%, and the negative predictive value was 98.6%. The cytosphere assay was highly correlative to flow cytometry in determining CD4+ and CD8+ T-lymphocyte counts among HIV-infected patients. The ease and limited resources needed to perform this test make it ideal in developing countries and other areas where technology and finances are limited.  相似文献   
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Sixteen patients with bullous pemphigoid were examined using direct and indirect immunofluorescent techniques with antisera specific for C1q, C4, C3, C5, C3 proactivator, properdin, fibrinogen, IgA, IgM, IgG and IgE. The results of these studies are consistent with the activation of complement via the classical (antibody–C1q) sequence as well as via the alternate pathway. Fibrinogen and/or fibrin derivatives were demonstrated on the basement membrane of ten of fifteen patients tested and IgE basement membrane staining was found in four individuals.  相似文献   
6.
Review of nocardial infections in France 1987 to 1990   总被引:15,自引:0,他引:15  
On the basis of the numbers ofNocardia strains referred to the National Reference Center for Mycoses and Antifungal Agents (NRC), Institut Pasteur, Paris, in the period from 1987 to 1990, it was estimated that between 150 and 250 cases of nocardiosis are diagnosed in France each year. A total of 63 clinical isolates were referred to the NRC and identified asNocardia asteroides (66.7 %),Nocardia farcinica (23.8 %),Nocardia brasiliensis (3.2 %),Nocardia otitidiscaviarum (4.8 %) andNocardia carnea (1.5 %).Nocardia asteroides accounted for 71.4 % of pulmonary infections, 80.0 % of central nervous system infections and 80.0 % of systemic infections. Patients infected withNocardia farcinica died in 57.1 % of cases, compared with 17.6 % of patients infected withNocardia asteroides. Corticosteroid therapy represented a significant factor in mortality. Isolates ofNocardia asteroides revealed variable resistance, whereas isolates ofNocardia farcinica were resistant to most antimicrobial agents. Only amoxicillin/clavulanic acid, imipenem, cefoxitin, kanamycin, amikacin, minocycline and vancomycin showed activity against both species. Nocardiosis caused byNocardia farcinica may be a growing problem because of the relatively high incidence in AIDS patients and the resistance of this species to most antimicrobial agents.  相似文献   
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RATIONALE AND OBJECTIVES: To evaluate the interpretation of computed tomographic pulmonary angiograms performed outside of regular reporting hours, comparing the initial interpretation by the radiology resident to the attending radiologist. MATERIALS AND METHODS: Records for 840 consecutive computed tomographic pulmonary angiograms (CTPA) performed outside of regular reporting hours at two tertiary referral centers from January 1, 2004-December 31, 2005 were reviewed. The preliminary interpretation by the on-call radiology resident was compared to the subsequent final report issued by a subspecialty trained chest radiologist. Studies were stratified as positive, negative, or equivocal for pulmonary embolus. Cases with discordant interpretations or negative CTPA were reviewed to determine impact on clinical outcome. Patients were followed up to 12 months after CTPA to document any subsequent thromboembolic event. RESULTS: Sixteen percent (131/840) of CTPAs were reported positive by the staff radiologist. There was agreement in 90% (752/840) of studies (P = .76, 95% confidence interval, 0.71-0.81) with 86% (114/133) agreement for studies interpreted as positive by residents, 95% (582/612) for studies interpreted as negative by residents, and 63% (60/95) for studies interpreted as equivocal by residents. Studies of optimal quality had higher interobserver agreement than studies of suboptimal quality (P < .0001). In-patient studies were more likely to be positive than emergency room patients (20% vs. 13%) (P = .004). No adverse clinical outcomes were attributed to discordant interpretations. CONCLUSIONS: Radiology residents provide a high level interpretation of on-call CTPA studies, achieving good concordance with the attending radiologists' assessment.  相似文献   
10.
Is Routine Cholecystectomy Required During Laparoscopic Gastric Bypass?   总被引:4,自引:0,他引:4  
Background: Routine cholecystectomy is often performed at the time of gastric bypass for morbid obesity. The aim of our study was to determine the incidence of gallstone formation requiring cholecystectomy following a laparoscopic Roux-en-Y gastric bypass (LRYGBP). Methods: 289 LRYGBP were performed between November 1999 and May 2002. 60 patients (21%) who had prior cholecystectomy were excluded. If gallstones were identified by intra-operative ultrasound (IOUS), simultaneous cholecystectomy was performed. Patients without gallstones were prescribed ursodiol for 6 months and scheduled for follow-up with transabdominal ultrasound. Results: During LRYGBP, gallstones were detected in 40 patients using IOUS (14%) and simultaneous cholecystectomy was performed. Of 189 patients with no stones identified by IOUS, 151 patients (80%) had a postoperative ultrasound after 6 months. 39 patients developed gallstones (22%) and 12 developed sludge (8%), as demonstrated by ultrasound at the time of follow-up. 11 patients had gallstone-related symptoms and subsequently underwent cholecystectomy (7%). 106 patients (70%) were gallstone-free at the time of ultrasound follow-up. Ursodiol compliance was found to be significantly lower for patients developing stones than for gallstone-free patients (38.9% vs 58.3%, z =-2.00, P = 0.045). Conclusions: There is a low incidence of symptomatic gallstones requiring cholecystectomy after LRYGBP. Prophylactic ursodiol is protective. Routine IOUS and selective cholecystectomy with close patient follow-up is a rational approach in the era of laparoscopy.  相似文献   
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