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Virus isolation studies and human immunodeficiency virus (HIV) antibody testing were performed on 87 household contacts of 68 HIV antibody-positive hemophilic patients to determine the extent that HIV could be transmitted through heterosexual or through nonsexual, but intimate contact. Human immunodeficiency virus seropositivity was established for the 68 hemophiliacs by immunofluorescence method or enzyme-linked immunosorbent assay and confirmed by Western blot testing (for 66 patients). Fifty-one nonsexual contacts and 36 sexual partners of these hemophiliacs were tested for HIV antibody by immunofluorescence or enzyme-linked immunosorbent assay and Western blot. All sexual partners and all nonsexual household contacts were HIV antibody-negative, including six partners and nine parents of hemophiliacs from whom the virus had been isolated and seven parents and six partners of patients with AIDS. This study further demonstrates lack of transmission of HIV in intimate, but nonsexual settings, and suggests that heterosexual transmission, although well known to occur, may be relatively uncommon in hemophilic couples when the male and female partner have no other risk factors. It is hoped that intensive education and counseling programs will reduce exposure and maintain a low risk of heterosexual transmission.  相似文献   
907.
In this report, we describe how transesophageal echocardiography was used not only to diagnose incorrect cannula position of a right ventricular assist device in the left atrium through a patent foramen ovale, but also to guide and to confirm correct cannula placement.  相似文献   
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MCF-7 breast tumor cells form multicellular nodules (foci) over a confluent monolayer in an estradiol (E2)-dependent, antiestrogen-sensitive reaction. A cell line cloned from MCF-7 that displays these phenotypes was probed to determine the effects of long term exposure to tamoxifen on the growth of foci, estrogen receptor alpha (ERalpha) status, and gene responsiveness to E2. In one of two experiments, a heterogeneous cell population emerged (TMX2) that over-expressed estrogen receptor alpha wild type mRNA (ERalpha mRNA) (approximately 20-fold) missing exon 3 (ERDelta3 mRNA) and its corresponding protein (ERDelta3P). On a per mRNA to protein basis, ERDelta3P and wild-type ERalpha were equivalently expressed. Return of the TMX2 population to medium without tamoxifen eventually selected for a population that expressed predominately wild-type ERalpha, whereas TMX2 clones over expressing ERDelta3 mRNA and ERDelta3P retained this phenotype in tamoxifen-free media. In both experiments, expression of all ERalpha mRNAs and proteins declined to barely detectable levels during 6-12 months exposure, concomitant with a progressive increase in the ability of the cells to form foci independently of E2 or tamoxifen. Selection for these various populations suggests that tamoxifen can induce and/or support certain cellular changes that lead to altered ERalpha expression, E2-independent cell growth and resistance to antiestrogens.  相似文献   
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Azathioprine therapy in chronic ulcerative colitis   总被引:7,自引:0,他引:7  
We evaluated the efficacy of azathioprine (Az) therapy in chronic ulcerative colitis (CUC) retrospectively in a clinic population from 1977 to 1987. The study was an open one. Sixteen patients were treated with a total of 20 courses of Az. Mean dose of Az was 1.48 mg/kg/d (range 0.98-1.82). All patients were on oral prednisone at the initiation of Az therapy. Indications for Az were: inability to wean off steroids without symptoms of CUC (12/20), poor response to steroids (7/20), and steroid toxicity (1/20). Responses to Az occurred in 15/20 courses (12/16 patients). Two patients had side effects requiring Az discontinuation. The mean duration of follow-up was 52.6 months with no incidence of malignancies. We conclude that the use of Az in selected patients with CUC who are steroid resistant or steroid dependent may be both efficacious and safe.  相似文献   
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