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41.
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Persons with non-A, non-B hepatitis (cases) identified in 5 transfusion studies in the early 1970s have been followed ever since and compared for outcome with matched, transfused, non-hepatitis controls from the same studies. Previously, we reported no difference in all-cause mortality but slightly increased liver-related mortality between these cohorts after 18 years follow-up. We now present mortality and morbidity data after approximately 25 years of follow-up, restricted to the 3 studies with archived original sera. All-cause mortality was 67% among 222 hepatitis C-related cases and 65% among 377 controls (P = NS). Liver-related mortality was 4.1% and 1.3%, respectively (P =.05). Of 129 living persons with previously diagnosed transfusion-associated hepatitis (TAH), 90 (70%) had proven TAH-C, and 39 (30%), non-A-G hepatitis. Follow-up of the 90 TAH-C cases revealed viremia with chronic hepatitis in 38%, viremia without chronic hepatitis in 39%, anti-HCV without viremia in 17%, and no residual HCV markers in 7%. Thirty-five percent of 20 TAH-C patients biopsied for biochemically defined chronic hepatitis displayed cirrhosis, representing 17% of all those originally HCV-infected. Clinically evident liver disease was observed in 86% with cirrhosis but in only 23% with chronic hepatitis alone. Thirty percent of non-A, non-B hepatitis cases were unrelated to hepatitis viruses A,B,C, and G, suggesting another unidentified agent. In conclusion, all-cause mortality approximately 25 years after acute TAH-C is high but is no different between cases and controls. Liver-related mortality attributable to chronic hepatitis C, though low (<3%), is significantly higher among the cases. Among living patients originally HCV-infected, 23% have spontaneously lost HCV RNA.  相似文献   
43.
BACKGROUND: Recent studies have demonstrated the antihypertensive effect of slow breathing exercises, guided interactively by a device, in patients with uncontrolled blood pressure (BP) without changing medication. This study examined the response to the same treatment protocol in resistant hypertensives. METHODS: Seventeen resistant hypertensives exercised device-guided slow breathing for 8 weeks, 15 min daily, and self-monitored BP. Data stored in the devices were collected on a PC-based system. Clinical outcomes were office and home BP changes from baseline to end values. RESULTS: Significant reductions in both office BP (-12.9/-6.9 mm Hg, P <.001 and home BP (-6.4/-2.6 mm Hg, P <.01/P <.05) without side effects with 82% responders and good compliance. CONCLUSIONS: Resistant hypertensives can benefit from and are compliant with self-treatment by device-guided slow breathing.  相似文献   
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Hepatitis B immune globulin (HBIG) and immune serum globulin (ISG) were examined in a randomized, double-blind trial to assess their relative efficacies in preventing type B hepatitis after needle-stick exposure to hepatitis B surface antigen (HBsAG)-positive donors. Clinical hepatitis developed in 1.4% of HBIG and in 5.9% of ISG recipients (P = 0.016), and seroconversion (anti-HBs) occurred in 5.6% and 20.7% of them respectively (P less than 0.001). Mild and transient side-effects were noted in 3.0% of ISG and in 3.2% of HBIG recipients. Available donor sera were examined for DNA polymerase (DNAP) and e antigen and antibody (HBeAg; anti-HBE). Both DNAP and HBeAg showed a highly statistically significant correlation with the infectivity of HBsAg-positive donors. Hepatitis B immune globulin remained significantly superior to ISG in preventing type B hepatitis even when the analysis was confined to these two high-risk subgroups. The efficacy of ISG in preventing type B hepatitis cannot be ascertained because a true placebo group was not included.  相似文献   
47.
OBJECTIVES: To determine the prevalence of antibodies to hepatitis C virus (HCV) in female sexual partners of multitransfused men with hemophilia and to compare the frequency of transmission of HCV and human immunodeficiency virus (HIV). STUDY DESIGN: Cross-sectional measurement of HCV and HIV antibodies. SETTING: Ten hemophilia treatment centers. PATIENTS: A total of 234 female sexual partners of 231 multitransfused men with hemophilia. MEASUREMENTS AND MAIN RESULTS: The prevalence of antibodies to HCV (anti-HCV) among female sexual partners of HCV-positive men was 5 of 194 (2.6%). Anti-HIV prevalence among female sexual partners of HIV-positive men was 25 of 196 (12.8%). Five (3%) of the 164 female sexual partners of HIV-positive/HCV-positive men were infected with HCV compared with none of the 30 female sexual partners of HIV-negative/HCV-positive men. Twenty-one (13%) of the 164 female sexual partners of HIV-positive/HCV-positive men were infected with HIV compared with 4 (13%) of 32 female sexual partners of HIV-positive/HCV-indeterminate men. The co-infected men were five times more likely to transmit both viruses than would be expected by chance (P = 0.01). When a single virus was transmitted to a female sexual partner, it was more often HIV than HCV (18 of 164 compared with 2 of 164, P = 0.001; odds ratio, 8.5; 95% Cl, 2.2 to 33.1). CONCLUSIONS: The higher prevalence of HCV in female sexual partners of men with hemophilia than in blood donor and other low-risk groups suggests that there is a low level of sexual transmission. Male to female sexual transmission of HCV is less efficient than that of HIV. The frequency of HCV transmission to sexual partners is five times higher when HIV is also transmitted, suggesting that HIV may be a cofactor for the sexual transmission of HCV.  相似文献   
48.
Nash  GB; Johnson  CS; Meiselman  HJ 《Blood》1986,67(1):110-118
Although the rheological behavior of sickle cell suspensions and of hemoglobin S solutions is known to be strongly dependent on oxygen tension (PO2), little data exist concerning the influence of PO2 on the viscoelasticity of individual HbSS RBC. We have used micropipette aspiration techniques to test the deformation response of both HbSS and control HbAA RBC over a wide range of PO2 at 23 degrees C. Sickled, spiculed HbSS cells were present for PO2 approximately less than 35 mm Hg; for a number of these cells, the deformation response was essentially elastic and an effective membrane rigidity (EMR) was calculated. EMR increased with decreasing PO2 and was approximately 5 to 50 times higher than the equivalent rigidity of oxygenated HbSS RBC. In addition, the rate of membrane deformation was very slow for sickled cells; the half-time for the deformation process increased as PO2 was lowered and was about two orders of magnitude longer than the equivalent time for normal RBC. Other sickled cells exhibited plastic deformation when subjected to comparable deforming forces and experienced irreversible membrane deformation and budding. At all PO2 levels tested, some HbSS RBC remained as discocytes; these cells had normal membrane elasticity and membrane viscosity. Furthermore, changes in PO2 did not affect the membrane properties of HbAA RBC. Thus, gross abnormalities in the deformation response of HbSS RBC were only detected after morphological sickling had occurred. These abnormalities most likely arose from changes in the cytoplasmic HbS viscoelasticity and, if present in vivo, would be expected to impair the flow of HbSS cells in the microcirculation.  相似文献   
49.
Ehninger  G; Schuler  U; Renner  U; Ehrsam  M; Zeller  KP; Blanz  J; Storb  R; Deeg  HJ 《Blood》1995,85(11):3247-3249
In a canine model we investigated the toxicity and pharmacokinetics of a water soluble busulfan preparation. Busulfan was dissolved in dimethylsulfoxide (DMSO) and administered either orally or intravenously in a single dose of 1 mg/kg. The application in either preparation was well tolerated. In seven dogs, peak levels in the range of 730 ng/mL to 1,000 ng/mL were measured after intravenous injection with an area under curve (AUC) of 75 ng.h/kg.mL to 146 ng.h/kg.mL. It was of note that even the oral administration of the same busulfan preparation resulted in AUC values in the same range as observed after parenteral application. The absorption rate of busulfan tablets in our model was as unpredictable as documented in clinical trials. On the basis of the present study, clinical trials using busulfan dissolved in DMSO given either intravenously or orally appear warranted. This approach should lead to predictable blood levels, reduced toxicity, and increased efficacy of busulfan-containing regimens.  相似文献   
50.
CD40 was originally described as a B-cell-restricted antigen and was subsequently found to be a member of the tumor necrosis factor (TNF) receptor superfamily. CD40 is also expressed on dendritic cells, thymic epithelium, monocytes, and some carcinoma cell lines, and plays a critical role in cell contact-dependent activation. Primary and cultured Hodgkin and Reed-Sternberg (H-RS) cells, the presumed malignant cells of Hodgkin's disease (HD); were found to express high levels of cell surface CD40. We found that recombinant CD40 ligand (CD40L) induced interleukin-8 (IL-8) secretion and enhanced IL-6, TNF, and lymphotoxin-alpha (LT-alpha/TNF-beta) release from cultured H-RS cells. These cytokines play a significant role in the clinical presentation and pathology of HD, a tumor of cytokine-producing cells. CD40L had no mitogenic activity for HD-derived cell lines. In contrast, CD40L enhanced expression of costimulatory molecules intracellular adhesion molecule-T and B7-1 on cultured H-RS cells, both of which are overexpressed on primary H-RS cells. In addition, CD40L induced a 40% to 60% reduction of the expression of the HD-associated CD30 antigen, another member of the TNF receptor superfamily. Primary and cultured H- RS cells express not only CD30, but also CD40. CD40L has pleiotropic biologic activities on H-RS cells, and the CD40-CD40L interaction might be a critical element in the deregulated cytokine network and cell contact-dependent activation cascade typical for HD.  相似文献   
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