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41.
The CD4+ CD8- inducer helper cell and the CD4- CD8+ cytotoxic/suppressor cell absolute numbers were measured in the peripheral blood of patients with various pathological conditions: with leukemia-lymphomas or solid tumors, patients with bone marrow grafts suffering from GvH, HIV-1 asymptomatic carriers, ARC and AIDS patients. The study was carried out during observation periods when they were not suffering from opportunistic infections and were untreated. In all the groups a decrease of the CD4+ CD8- cell absolute number was observed. In the leukemia-lymphoma and solid tumor bearing patients the CD4- CD8+ absolute value was lower than normal, while in the GvH- and HIV-infected patients, it was significantly higher. The clinical follow-up of each group indicates that GvH, ARC and AIDS patients developed infection in 40-68% of the cases, ie the only groups at risk of infection are those in which the CD4- CD8+ absolute values are high: we suggest that the balance CD4+ versus CD8+ should be considered rather the absolute CD4+ when discussing appropriate use of immuno-regulators.  相似文献   
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High-frequency rotational angioplasty is a recently developed method for coronary angioplasty in the catheter laboratory. An elliptical burr tip (phi 1.25-2.0 mm) with embedded diamant chips (phi 40-50 microns) is rotated by a helical drive shaft at 150,000-180,000 rpm. The burr is advanced over a 0.009-inch coaxial guide wire. To show the effects of this approach in diseased and healthy vessels, which may be present before and behind a stenosis, 17 atherosclerotic coronary arteries of nine human hearts, and 18 normal coronary arteries of nine pig hearts were treated by this method in vitro. Standardized coronary angiography was performed before and after Rotablator treatment, followed by histological examination. From these data the burr-to-vessel-diameter ratio was calculated for each vessel segment and compared with the angiographical and histological outcome. Partial or complete removal of the circumference of the innermost vessel wall layers was observed regularly. The average removal of tissue in human coronary arteries was limited to the intimal layer and in the pig coronary arteries to the internal elastic membrane. In the pig coronary arteries no intimal tears or dissections occurred, in human coronary arteries tears could be seen frequently (13 of 17 vessels (76%)). Media tears were observed in 3 of 17 vessels; one (2%) media dissection could be demonstrated; no perforation occurred. Thus, the in vitro studies suggest that coronary rotational angioplasty has only a slight effect on the vessel segment next to a stenosis, regardless of the burr-to-vessel-diameter ratio.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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The Onchocerciasis Control Program of the World Health Organization is carrying out an extensive screening program in a search for new larvicides to be used for control of Simulium damnosum s.l. Emphasis has been given to finding a pyrethroid and a carbamate to supplement the organophosphates currently in use. These chemicals with differing modes of action, together with Bacillus thuringiensis H-14, are being used in an attempt to cope with the development and spread of resistance to the organophosphates temephos and chlorphoxim.  相似文献   
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PURPOSE: Amiodarone (AMIO), a widely used anti-arrhythmic drug, has been shown to reduce the incidence of atrial fibrillation after cardiac surgery and also to exert immunomodulatory actions in vitro and proinflammatory effects in vivo. The present study investigated the immunomodulatory properties of AMIO in the inflammatory response induced by cardiac surgery with cardiopulmonary bypass (CPB). METHODS: In this double-blind, placebo-controlled trial, 20 patients undergoing elective coronary artery bypass graft were randomized to receive placebo or AMIO 600 mg day(-1) orally for seven days before surgery and 45 mg hr(-1) intravenously for 48 hr postoperatively. Plasma levels of the proinflammatory markers C-reactive protein (CRP), fibrinogen (FBG), tumour necrosis factor (TNF)-alpha, interleukin (IL)-6 and monocyte chemoattractant protein (MCP)-1, and the antiinflammatory marker IL-10, were compared before and after surgery. RESULTS: Ninety-six hours after start of surgery, plasma levels of FBG had more than doubled (2.2 +/- 0.5-fold increase, P < 0.0001). Overall, FBG formation was significantly increased in the AMIO group (P = 0.048). Monocyte chemoattractant protein 1 secretion transiently increased four hours after start of surgery (6.6 +/- 4.5-fold increase) but rapidly declined thereafter, (P < 0.0001). There was a trend toward higher MCP-1 plasma concentrations in the AMIO group (P = 0.13). The plasma levels of CRP, TNF-alpha, IL-6 and Il-10 changed significantly over time, but were not altered by AMIO treatment. CONCLUSION: In the inflammatory response induced by cardiac surgery with CPB, our data suggest that AMIO treatment is associated with a selective trend toward proinflammatory actions.  相似文献   
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In very preterm neonates, bronchopulmonary dysplasia (BPD) complicates the course of respiratory distress syndrome, i.e., primary surfactant deficiency in a structural immature lung. In Germany, about 11 000 preterms having a gestational age below 32 weeks are born and treated in neonatal intensive care units per year. Within this high risk group, the rate of BPD is about 15%. Relevant prenatal risk factors include intrauterine inflammatory fetal reaction as a consequence of ascending maternal infections, intrauterine growth retardation apart from the main risk factor immaturity. Postnatal risk factors include genetic predisposition, mechanical ventilation, infections and hemodynamically relevant patent ductus arteriosus.Preventive measures include intratracheal surfactant administration; new studies indicate preventive effects of caffeine, vitamin A and hydrocortisone in a subgroup of neonates with prenatal fetal inflammatory response.Due to long-term detrimental effects of BPD on lung function and psychomotor development, further experimental and clinical studies are mandatory in order to continue to reduce the BPD rate.  相似文献   
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