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991.
Qualitative and quantitative evaluations of the cellular components of bronchoalveolar washings of calves with experimental parainfluenza-3 virus pneumonitis and control calves were made. Calves were exposed to 10(9) TCID50 of PI-3 by intranasal aerosol exposure and bronchoalveolar cells obtained 7 days after infection by volume-controlled bronchopulmonary lavage. Transient tachypnea and pyrexia occurred in all infected calves, and virus was recoverable at 7 days from nasal swabs and lung tissue. Pulmonary lesions were typical of viral pneumonitis, characterized by patchy alveolitis and bronchiolitis with accumulations of cells and inflammatory debris. The mean total lavage cell yield was elevated in the virus-infected calves, and the percentage of neutrophils was elevated (P less than 0.05). Increased numbers of pulmonary alveolar macrophages (PAM) were also recovered but the difference was not significant. Linear regression equations showed that a decreased proportion of PAM from virus-infected animals were phagocytic. The mean initial phagocytic rates of macrophages from calves with viral pneumonitis were significantly decreased (P less than 0.05) over controls. This difference was concentration dependent and required a phagocytic stimulus in excess of 12.5 X 10(6) beads/ml. Studies of phagocytic kinetics showed that PAM from calves with viral pneumonitis had a lower Vmax than PAM from control calves, but that Km values were comparable. No differences in PAM beta-glucuronidase and acid phosphatase activity were observed. These results indicate depressed phagocytic function in PI-3 virus-inflamed lungs relative to controls. In concert with virus-induced airway lesions, such in vivo depression of PAM phagocytic functions would be expected to depress pulmonary particulate clearance and lung defense mechanisms. 相似文献
992.
Some 2-methyl-3-triazole-substituted-4(3H)-quinazolinones 3a-f were prepared and tested for their H1- and H2-antihistaminic activities. In addition these compounds are central nervous system depressants and anticonvulsants. 3e shows highly significant decrease of locomotor activity. 相似文献
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The adaptation in activation patterns of the ankle extensor muscles to different functional demands was studied in adult men (n = 10) and 9-year-old boys (n = 10). The relative magnitude of the activation of the slow soleus (SOL) and the relatively fast medial gastrocnemius (MG) muscle was measured during various postures and hopping tasks on a force plate. In addition, the myo-electric activity was quantified in three different phases of the stretch-shortening cycles during hopping. Major differences between boys and adults were observed in the postural tasks, where the boys appeared to utilize the MG to a relatively larger extent. During maximal height hopping there was a clearly larger potentiation of the MG activity in the adults, particularly in the eccentric phase. On the other hand, there were striking similarities between boys and adults with respect to the degree of pre-activation of both muscles during the different hopping regimes as well as potentiation of muscle activity during the concentric phase of maximal height hopping. Thus, some aspects of the selective neural control of the ankle extensor muscles appear to be manifested in pre-pubertal boys. However, the data also indicate that other factors, such as utilization of stored elastic energy in the muscles and stretch reflex potentiation, will still continue to develop from the age of nine. 相似文献
997.
O Lindvall S Rehncrona P Brundin B Gustavii B Astedt H Widner T Lindholm A Bj?rklund K L Leenders J C Rothwell 《Archives of neurology》1989,46(6):615-631
By using stereotaxic surgical techniques, ventral mesencephalic tissues from aborted human fetuses of 8 to 10 weeks' gestational age were implanted unilaterally into the striata in two patients with advanced Parkinson's disease. The patients were treated with a cyclosporine, azathioprine, and steroid regimen to minimize the risk for graft rejection. They were examined for 6 months preoperatively and 6 months postoperatively and continued to receive the same doses of antiparkinsonian medication. There were no significant postoperative complications. No major therapeutic effect from the operation was observed. However, in the clinical tests, both patients showed small but significant increases of movement speed for repeated pronation-supination, fist clenching, and foot lifting. The rate of walking also increased in the one patient tested. For both patients, there was an initial worsening postoperatively, followed by improvement vs preoperative performance at 1 to 3 months. Both patients also showed significant improvement in the magnitude of response to a single dose of levodopa (L-dopa), but there was no increase in the duration of drug action. The motor readiness potential increased in both patients postoperatively, primarily over the operated hemisphere. Neurophysiological measurements also showed a more rapid performance of simple and complex arm and hand movements on the side contralateral to transplantation in one patient at 5 months postoperatively. Positron emission tomography demonstrated no increased uptake of 6-L-(18F)-fluorodopa in the transplanted striatum at 5 and 6 months. Taken together, these results suggest that the fetal nigral implants may have provided a modest improvement in motor function, consistent with the presence of small surviving grafts. Although our results support further scientific experimentation with transplantation in Parkinson's disease, widespread clinical trials with this procedure are probably not warranted at this time. 相似文献
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Bernard Stuart Declan Fox Harry Murphy Bryan Lynch J. Loftus E. Naughten I. Saul O. Sheil N. Duignan A. Jackson W. A. Gorman G. Fox T. Matthews T. Clarke Mark M. Reid H. L. Halliday B. G. McClure P. S. Thomas Michael O’Dowd Michael J. O’Dowd Kevin Connolly F. Leahy Dr. R. G. White Ruth Connolly Colm O’Herlihy Alicja Radic Dr. 《Irish journal of medical science》1986,155(6):209-212