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781.
A J Crottogini J R Depaoli J G Barra E C Fischer M Rodríguez Chatruc R H Pichel L de la Fuente 《American heart journal》1985,110(4):753-760
The effect of the new calcium antagonist nisoldipine (BAY k-5552) on myocardial infarct size was studied in four groups of conscious dogs undergoing acute left anterior descending coronary artery occlusion. Group I received placebo for 48 hours before and for 24 hours after occlusion; group II received placebo before and nisoldipine (0.3 mg/kg orally every 6 hours) after occlusion; group III received nisoldipine before and placebo after occlusion; and group IV received nisoldipine before and after occlusion. Infarct size was quantified with the tetrazolium red staining technique. Infarcted ventricular mass was 24.5 +/- 6.6% (mean +/- SD) for group I (control), 21.4 +/- 4.4% for group II (p = NS against control), 13.9 +/- 4.5% for group III (p less than 0.05), and 14.1 +/- 4.0% for group IV (p less than 0.05). Post occlusion sudden death was 30% in non-pretreated dogs and 0% in pretreated dogs (p less than 0.001). We conclude that prophylactic oral treatment with nisoldipine decreases infarct size and lowers the incidence of sudden death in conscious dogs undergoing acute coronary occlusion. 相似文献
782.
Morio B Barra V Ritz P Fellmann N Bonny JM Beaufrère B Boire JY Vermorel M 《European journal of applied physiology》2000,81(4):329-336
The present study assessed daily activity, physical capacity and body composition in 11 initially sedentary healthy subjects
[5 men and 6 women, mean age 62.8 (SD 2.7) years] before training (To), after completion of 7 (T7w) and 14 (T14w) weeks of training, and again 6 (T6m) and 12 (T12m) months after training. The mean daily activity index decreased from T7w to T12m reaching a lower level than at To [T12m − To = −1.5 (SD 4.6) units, P = 0.18]. Mean maximal oxygen uptake (V˙O2max) and its corresponding mean power output (W˙
max) were increased by 12.5 (SD 6.6)% (P = 0.003) and 22.8 (SD 12.8)% (P = 0.003), respectively, at T14w, and returned to their To levels within 1 year. Mean body mass (m
b) remained stable until T6m but increased significantly by 2.6 (SD 3.7)% from T6m to T12m (P < 0.05). Mean fat mass (m
f, from bioelectrical impedance analysis measurements) tended to decrease [−2.0 (SD 4.2)%, P = 0.10] during the training period but increased by 7.8 (SD 10.9)% between T6m and T12m (P < 0.05). The mean fat free mass did not vary during the study period (P = 0.81) but magnetic resonance imaging (MRI) showed that mean thigh muscle volume decreased between T7w and T12m to less than at To [T12m − To = −2.3 (SD 3.6)%, P = 0.05]. Therefore, this study confirmed the favourable effects of endurance training on the physical capacity and body composition
of elderly people, but demonstrated that the training programme would have to be continued to maintain the training-related
benefits (i.e. increased V˙O2max and W˙
max) which would otherwise be lost within 1 year. After training, m
b and m
f were found to be increased. Furthermore, a fast and reproducible MRI protocol was validated for study of small intra-individual
variations in tissue volumes in longitudinal studies.
Accepted: 7 September 1999 相似文献
783.
Claudia P. Sanchez-Castillo Peter J.S. Dewey Antonia Aguirre Jose J. Lara Rebeca Vaca Patricia Leon de la Barra Margarita Ortiz Ismael Escamilla W.Philip T. James 《Journal of food composition and analysis》1998,11(4):340-356
As part of the development of new food composition tables for Mexico, a number of fruit and vegetable samples, grown in Mexico, were purchased fresh from the main market in Mexico City. After washing and drying to remove contaminants, the samples were freeze dried and analyzed for the major elements (Na, K, Ca, P, Mg, Fe) by flame photometric and spectrophotometric procedures and for the minor and trace elements (Cu, Zn, Mn, Co, Cr, Cd, Pb) by atomic absorption spectrophotometry. The results are compared with those from the United Kingdom and German food composition tables. In general there were no consistent differences between the European and Mexican data, though the P content of Mexican fruits tended to be lower. There were noticeably higher Pb levels in Mexican fruits than those of United Kingdom origin, while root and green vegetables showed similar Pb levels. 相似文献
784.