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排序方式: 共有744条查询结果,搜索用时 22 毫秒
731.
G J Gilson L A Izquierdo M S Chatterjee L B Curet C R Qualls 《The Western journal of medicine》1993,159(2):149-152
We investigated the effect of preinduction cervical ripening with the intracervical instillation of dinoprostone (prostaglandin E2 gel, 0.5 mg) on the results of labor induced with intravenous oxytocin. We randomly allocated 79 pregnant women to receive either the intracervial application of dinoprostone gel or placebo gel. Compared with control subjects, the group who received dinoprostone had no difference in induction-to-delivery interval or in cesarean section rate. The dinoprostone group had fewer failed inductions, but there was no difference between the two groups in the number who delivered spontaneously within 24 hours. From review of the literature and a meta-analysis, it was likewise revealed that dinoprostone did not favorably affect the cesarean section rate. Contrary to current opinion, intracervical dinoprostone gel does not appreciably lower the cesarean section rate when used at this dose and route before labor is induced. 相似文献
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734.
P. Morán A. M. Pendas E. García-Vázquez J. I. Izquierdo J. Lobón-Cervlá † 《Journal of fish biology》1995,46(4):593-602
Between-population gene flow was estimated in neighbouring freshwater and anadromous Salmo trutta populations from Asturias, Northern Spain. Populations from the same drainage showed a high mean level of gene flow. Gene flow was also found between populations from different drainages and was negatively related to the distance between river mouths. The strength of the homing orientation of migratory individuals (sea trout) is discussed. 相似文献
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Memory disruption by posttraining electroconvulsive shock was studied in adult Wistar rats using three different tasks: step-down inhibitory avoidance, two-way active avoidance, and habituation of rearing to an open field. The animals were given training and test sessions 24 hours apart in each of these tasks. Immediate posttraining transcorneal, 15 mA, 60 Hz, 2 sec electroconvulsive shock disrupted memory of the three tasks. The effect was completely reversed by the IP administration of beta-endorphin (2.0 micrograms/kg), 6 min prior to testing, or of another electroconvulsive shock, 30 min prior to testing. These findings indicate that the posttraining electroconvulsive shock did not affect memory storage. In view of the fact that electroconvulsive shock has been previously shown to cause a pronounced decrease of brain beta-endorphin immunoreactivity, attributable to a release of the peptide, the present findings can be interpreted as showing that memory disruption by posttraining electroconvulsive shock results from the induction of state dependency on beta-endorphin. 相似文献
738.
P Cornago L Santos Y Smeyers C Lopez Zumel C Izquierdo 《Chemico-biological interactions》1992,82(1):47-53
The electron affinity of some glyoxylic compounds with radiosensitizing properties was evaluated using different approaches. The half-wave reduction potentials were measured by polarography, and the molecular structures in solution were determined by NMR spectroscopy. The electron affinity of the unhydrated and hydrated molecules was theoretically evaluated by means of a semi-empirical quantum mechanical procedure, the MNDO. The possible correlations between these values and the radiosensitizing efficiency of these glyoxylic compounds is discussed. 相似文献
739.
C.M. Guardiola G.C. Fahey J.W. Spears U.S. Garrigus O.A. Izquierdo C. Pedroza 《Animal Feed Science and Technology》1983,8(2):129-138
Experiments were conducted in vitro and in vivo to determine the effects of sulphur (S) supplementation of a good quality fescue hay containing 0.27% total S and a tropical star grass hay containing 0.20% total S. Addition of S was on an isosulphurous basis of either sodium sulphate or D,L-methionine. Cellulose digestion in vitro was improved (P < 0.001) by the addition of 1% urea. Supplementation of forage with 0.05, 0.10 or 0.15% S from either sodium sulphate or methionine also stimulated cellulose digestion in vitro. There were no differences between S sources. The addition of 0.4 or 0.8% nitrate-nitrogen (nitrate-N) (potassium nitrate) depressed (P < 0.05) cellulose digestion in vitro of both hays. No effect of animal adaptation to nitrate was evident. Addition of S partially counteracted the depression in cellulose digestion due to nitrate. Trials were conducted in vivo in which 12 crossbred wether lambs (fescue experiment) or 12 crossbred intact male lambs (star grass experiment) were randomly assigned to one of three treatments: control (forage with no addition of S); forage plus 0.15% S as sodium sulphate; and forage plus 0.15% S as D,L-methionine. Lambs were housed in metabolism crates and each experiment was replicated twice. Dry matter intakes were highest for methionine-supplemented fescue and for S-supplemented star grass, regardless of S source. Dry matter digestibility tended to increase with S addition (fescue experiment) and was significantly higher for S-supplemented star grass. There was a significant increase (P < 0.05) in neutral detergent fibre (NDF) and acid detergent fibre (ADF) digestibility due to supplemental S, regardless of S source. Nitrogen retention, ammonia-N and ruminal volatile fatty acids were unaffected by S supplementation. 相似文献
740.