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11.
We studied in 130 parturients during childbirth the effects of general anaesthesia by Alfatesine on the state of the foetus at birth. The examinations took into account the APGAR score, blood gas analysis, pH, bases excess in the umbilical artery and vein and the foetal EEG. The subjects are divided into three groups: prophylactic caesarians, extractions during labor in the absence of any foetal distress and extractions for reasons of acute or chronic foetal distress. The results are evaluated in comparison with the same tests conducted on a series of newborn infants in normal conditions and without anaesthesia. The APGAR score is hardly affected by the Alfatesine; the EEG is perturbed (but without any clinical manifestations) during the two hours following delivery. However, theses modifications are less pronounced than those observed with barbiturates. The study of blood gases and pH shows lower values under anaesthesia than without. 相似文献
12.
Among the 5612 pregnancies followed at the 2nd Obstetrical and Gynaecological Clinic of the University Hospital of Athens, from July 1969 to December 1974, laparotomy was undertaken 32 times for conditions not associated with pregnancy, an incidence of 0,58%. The laparotomy was performed because of ovarian cysts, fibroids, acute appendicitis and bowel obstruction. The accurate diagnosis, the fetal loss rate, maternal morbidity and mortality were discussed. 相似文献
13.
Cortical spreading depression is a wave of electrical and biochemical changes that spreads across the cerebral cortex. It has been hypothesized to be an important underlying cause of the visual disturbances occurring during the migraine aura, but this is difficult to test in animals or humans. We created a computational model of cortical spreading depression and found that during the wave of biochemical changes the spatial pattern of neural activity broke up into irregular patterns of lines and small patches of highly activated elements. The corresponding visual disturbances that would be produced by these patterns of neural activity resemble the hallucinations reported during the migraine aura, providing strong support for the cortical spreading depression hypothesis of migraine. The model also makes the testable prediction that these hallucinations move at an exponentially increasing speed across the visual field. 相似文献
14.
Whether late positive components of event-related potentials (ERPs) parallel changes in heart rate (HR) indicative of attention/orienting to rare stimuli has been debated. In the present study, a three-stimulus design was used, with rare target, rare nontarget, and frequent standard stimuli delivered under identical conditions except that instructions to subjects described the targets to which subjects should respond but did not describe the nontargets. In Experiment 1, stimuli varied among modalities; in Experiment 2, auditory stimuli were employed. Both ERPs and HR were consistent with automatic processing preceding two stages of controlled processing. Rare stimuli evoked larger parietal P300 and initial HR deceleration than standards. Presumably because of load-reducing effects of long interstimulus intervals, targets and nontargets were not distinguished before a late slow wave and a late phase of HR acceleration. Neither rare stimulus elicited a recognizable frontal P3a. 相似文献
15.
The effect of dissolved oxygen on the rate of chemical etching of copper by acidic cuprous chloride solution was investigated numerically for the case of a rotating disc electrode (RDE). Copper dissolution in aerated acidic cupric chloride solutions of composition 3.5M CuCl2 + 0.5M HCl + 0.5M KCl and 3.5M CuCl2+0.5M HCl was investigated with consideration of the instantaneous homogeneous reaction 4CuCl32-+4H++O2rlhar4CuCl 3-+2H2O which takes place within the mass transport boundary layer. It was assumed that CuCl32- and O2 react instantaneously, resulting in the formation of a reaction plane which separated the mass transport boundary layer into two regions: a region adjacent to the electrode where oxygen was depleted, and a region adjacent to the bulk where CuCl32- was absent. A one-dimensional mathematical model was developed to predict the position of the reaction plane. The model accounted for diffusion, migration and fluid flow generated by an RDE and included nine species and five heterogeneous electrochemical reactions. The homogeneous redox reaction served to regenerate the chemical etchant solution and thus enhance the etch rate. With increasing oxygen concentration and rotation rate the reaction plane was found to move closer toward the electrode and thus the etch rate of copper increased. Addition of KCl increased the Cl- content in solution so as to shift the reaction plane toward the bulk. 相似文献
16.
MASS TRANSFER IN GAS-SPARGED POROUS ELECTRODES 总被引:1,自引:0,他引:1
The electrochemical limiting current method was used to measure mass transfer coefficients with cocurrent upward gas-liquid flow in packed bed electrodes. Liquid-solid and overall gas-solid coefficients were determined from limiting current data in the presence of inert or reactive gas flows with the use of a plug flow model. The presence of inert gas flow increased mass transfer coefficients over those in single-phase flow by a factor of up to 1.7. As a result of boundary layer penetration by gas bubbles, sparging with reactive gas increased mass transfer rates by a factor of up to 3.5. 相似文献
17.
A review is presented of vesical-related paragangliomas and 3 cases are reported. Methods for early diagnosis, including selective angiographic demonstration, and treatment of these rare tumors are discussed. A multi-team approach by the urologist, endocrinologist and anesthesiologist is stressed for better control of potentially dangerous vasomotor changes during diagnosis and surgical treatment of this tumor. 相似文献
18.
Ro 2-2985 increased mean arterial blood pressure in both the venous bypass preparation and the intact animal; however, total peripheral resistance increased in the venous bypass preparation with a constant cardiac output but decreased in the intact animal with an increase in cardiac output. These observations indicate a drug-related increase in the distensibility of the aorta at the same arterial pressure. In vivo ventricular function curves were shifted to the left indicating enhanced myocardial performance with the translocation of large volumes of blood to the central circulation since total body venous compliance was significantly decreased. Beta adrenergic blocking doses of propranolol blocked the positive inotropic effect of Ro 2-2985 while myocardial depression produced by toxic doses of propranolol was reversed. This observation suggests several mechanisms for the Ro 2-2985 metabolic mediation of myocardial muscle contraction. The cardiovascular effects produced by Ro 2-2985 were accompanied by a marked polycythemia and a decrease in plasma volume without a change in total circulating blood volume, while blood glucose values showed a nonsignificant increase. Ro 2-2985 produced a marked increase in cardiac output. The increase in myocardial performance appears to be complex since myocardial force of contraction, dT/dt, dP/dt:P40 and Vmax were all increased. RO 2-2985 increased coronary flow without an increase in resistance. There were no significant increases in myocardial arteriovenous glucose, lactate, K+, Ca++, Na+ or Cl. 相似文献
19.