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21.
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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Over an eight year period 21 different viral strains excluding polioviruses were isolated in 44 (19%) of 237 cot deaths. The percentage of viral positive cases was significantly greater in over 16 week age groups and in cultures obtained less than 24 hours after death.  相似文献   
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Histological examination of the deciduous teeth in two cases of segmental odontomaxillary dysplasia (SOMD) showed fibrous enlargement of the pulps, an irregular pulp/dentine interface displaying many pseudoinclusions and pulp stones. There were tubular defects in the coronal dentine from pulp horn to cusp tip, an irregular tubular structure to the circumpulpal dentine of the apical half, a focally deficient odontoblast layer and widespread external resorption. Together with the clinical features of unilateral maxillary enlargement, upper alveolar expansion in the distal segment, increased spacing and delayed eruption of the deciduous molars and absence of premolar teeth, these histological appearances allow distinction of this condition from fibrous dysplasia (FD), segmental hemifacial hypertrophy (SHH) and regional odontodysplasia (ROD).  相似文献   
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Prediction of choledocholithiasis using a pocket microcomputer   总被引:4,自引:0,他引:4  
A computerized method, using a small pocket computer, has been used to predict the presence of choledocholithiasis in a prospective series of 239 patients undergoing cholecystectomy. From an initial data base of 424 patients 36 factors were evaluated and the most important 2 of these were determined by multivariate analysis for use in the prospective analysis. Satisfactory operative cholangiograms were a prerequisite to evaluation of the statistical method and were obtained in 90.4 per cent of cases. Using the computerized method a common bile duct stone would have been overlooked in only 1 patient but 17 unnecessary explorations would have been carried out. The overall accuracy of the computerized method was 92.5 per cent. When the method was applied to a further study of 97 patients from a separate centre the overall accuracy was 85.6 per cent. If the method was used to aid selective use of operative cholangiography, cholangiograms would be performed in 20 per cent and stones would be overlooked in less than 1 per cent.  相似文献   
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An open, randomized, cross-over study was performed to compare the efficacy and acceptability of two breath-actuated inhalers, the Turbohaler (T) and Diskhaler (D), for delivery of beta-agonists. Thirty six adults with chronic asthma requiring beta-agonists four times daily were treated with terbutaline 500 micrograms via T and salbutamol 400 micrograms via D four times daily, each period lasting four weeks. Additional bronchodilator via pressurized aerosol was permitted as required. Peak expiratory flow (PEF) was recorded in the morning (before and after beta-agonist) and in the evening. The mean morning PEF was higher during the first two weeks using T (295 l.min-1) than whilst using D (281 l.min-1, p < 0.01), but this difference did not persist during the second two weeks and there were no differences in post-bronchodilator PEF or rescue beta-agonist use. After four weeks, > 90% of patients used both inhaler devices efficiently and they were equally acceptable in terms of ease of use and convenience to carry. The Diskhaler and Turbohaler achieve similar clinical efficacy for delivery of beta-agonists.  相似文献   
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Many conventional dressings are painful when removed, and may be detrimental to healing. In a pilot study ten consecutive abscesses, requiring incision and drainage, were packed with a calcium alginate dressing: this was well tolerated, its removal causing minimal pain. No adverse effects were attributable to its use. A controlled trial was therefore carried out to compare calcium alginate with the more traditional saline-soaked gauze for packing abscess cavities, following incision and drainage. Patients were randomized to receive either calcium alginate (16 patients) or gauze dressing (18 patients). At the first dressing change the patient marked on a linear analogue scale the pain experienced; the nurse noted similarly the ease of removal of the dressing. Calcium alginate was significantly less painful to remove after operation (P less than 0.01), and also easier to remove (P less than 0.01) than gauze dressings. If abscess cavities are packed after incision and drainage, calcium alginate appears to be an improvement on conventional dressings.  相似文献   
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