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1.
The effect, on the agonistic behaviour of male mice, of urine from females which were either in oestrus or dioestrus, intact or ovariectomized, was examined. It was shown that the inhibitory effect on aggression previously demonstrated was independent of the state of oestrus and was unaffected by ovariectomy. In addition the presence of a factor in female urine which potentiates sexual behaviour in males was revealed. This effect was shown to be present at oestrus and not at dioestrus and to be abolished by ovariectomy. 相似文献
2.
V N Slavnov G V Valueva E V Luchitski? A A Iakovlev 《Biulleten' eksperimental'no? biologii i meditsiny》1981,92(8):49-51
A study was made of the activity of the hypothalamo-hypophyseo-adrenal system under the effect of peritol (ciprohepatadin), an antagonist of serotonin receptors. Experiments were carried ot on male rats in which the blood content of corticosterone, aldosterone and ACTH was determined 3, 6 hours and 14, 20 and 30 days after peritol administration (twice a day). Pronounced inhibitory effect on the hypothalamo-hypophyseo-adrenal system was found to be attainable on a more frequent exposure (every 3 hours) to peritol with a purpose of maintaining the optimal drug concentration in various body tissues. The latter circumstance gives rise to peritol effect which is realized through both the central mechanisms (ACTH content) and as a result of direct action on steroid output. 相似文献
3.
目的:探讨超声介入聚桂醇硬化剂治疗肝囊肿疗效的疗效。方法:将在我院76例被确诊为肝囊肿患者,随机分成治疗组(n=38)和对照组(n=38),治疗组在超声介入下囊肿内注入聚桂醇注射液,对照组采用乙醇治疗,比较两组住院时间、住院总费用、疗效以及不良反应。结果:治疗组患者抽出液(81.57±5.86)ml,对照组患者抽出液(91.71±7.80)ml,两组抽出液的差异有显著性(p0.05);治疗组和对照组患者住院时间分别为(4.86±0.90)天、(7.29±1.38)天,两组住院时间差异有显著性(P0.05);治疗组住院总费用为(4580.14±945.01)元,对照组患者住院总费用分别(4965.86±796.72)元;两组住院总费用差异无显著性(P0.05);治疗组总有效率为94.74%,对照组总有效率为81.58%,两组临床治疗效果差异有显著性(P0.05);两组患者不良反应发生例数无统计学差异(P0.05)。结论:聚桂醇作为新型硬化剂,疗效较好,不良反应少,可以成为囊肿超声介人治疗的首选硬化剂。 相似文献
4.
The effect of elevated levels of CO2 on the neurons of the metathoracic ganglion of the common house cricket was examined. Elevated CO2 produced a profound depolarization of the neurons without a substantial change in conductance. The depolarization was not due to CO2 acidification of the external solution since exposure of the neurons to a solution which was nominally CO2 free, but at an acid pH, produced little effect. The effect of elevated CO2 appeared to be due to intracellular acidification, since other treatments which acidified the cell interior also produced depolarization. Agents which block intracellular pH regulation also substantially enhance the effect and prevent recovery. The mechanism producing the depolarization appears to be blockage of a metabolic component of the resting potential, since the action of metabolic blockers mimics the effect of elevated CO2. 相似文献
5.
F Mendlovic S Corvera J A García-Sáinz 《Biochemical and biophysical research communications》1984,123(2):507-514
Platelet-activating factor (PAF) stimulates glycogenolysis and induces vasoconstriction in perfused rat liver. The effect of PAF was rapid but transient and it was blocked by indomethacin and bromophenacyl bromide which suggests a role of cyclooxygenase metabolites in its action. The homologous desensitization of glycogenolysis produced by PAF and the sensitivity of its actions to inhibitors of cyclooxygenase and phospholipase A2 markedly differentiate the mechanism of action of this agent with that of alpha 1-adrenergic agents, vasopressin or angiotensin II. No effect of PAF in isolated hepatocytes was observed which suggest that cells other than hepatocytes could be involved in its action in perfused liver. In addition nordihydroguaiaretic acid and bromophenacyl bromide abolished the vascular effect (but not the glycogenolysis) produced by epinephrine which suggest a role for lipoxygenase products in this effect. 相似文献
6.
In experiments with yeast cells it was shown that the synergistic effect of a combination of ionizing radiation and hyperthermia is a function of dose rate. It was demonstrated that the temperature at which radiation is delivered should be elevated to obtain the maximum synergistic effect with the increasing dose rate. 相似文献
7.
The number of grey levels, G, contained in a digitized image of an external event must affect the fidelity of reproduction of that event for physical reasons. The question arises as to whether there is a separate perceptual effect of G. Three experiments are described which investigate the effect of G on the visibility of a straight-line signal in visual noise using a signal detection analysis to separate the physical and perceptual effects of G. The results show that, for the type of displays employed, and for the specific task of detection of lines in visual noise, there was no effect of G on efficiency, which suggests that G had no separate perceptual effect. 相似文献
8.
《Cell biology international reports》1981,5(6):587-594
The hypothesis which attributes the motive power to the frontal zone has been tested by cinematographic analysis of the movements of amoeba, in which the front was either blocked by negative stimuli or destroyed. Partial inhibition and consecutive reorganization of the frontal activity by a beam of light had minor effect on the retraction of other body parts. Micrurgical destruction of the whole frontal zone had no effect on the functions of more posteriorly situated cell regions, which continue to contract and squeeze the endoplasm out into the external medium. 相似文献
9.
The effect of urbanization on the microbial content of the North Saskatchewan River was determined by following the changes in the numbers of total bacteria, total eosin methylene blue (EMB) plate count, and Escherichia coli as the river flowed from its glacial source, through parklands, and out into the prairies. Changes in physical parameters such as pH, temperature, salt concentration, and the amount and nature of the suspended material were also determined to evaluate their on the microbial parameters being measured. The level of all three microbial parameters studied slowly increased as the river flowed from its glacial source out into the prairies. The major effect of small hamlets, with or without sewage treatment facilities, appears to be to supply nutrients which supports the growth of the indigenous river flora but not E. coli. In contrast, the effect of a large urban center, with a population of approximately 500,000, which utilizes primary and secondary sewage processes in disposing of sewage, is to provide the nutrients and an inoculum of E. coli which results in a marked increase in the numbers of all three microbial groups studied. The effect of this urban center was still discernible 300 miles downstream. The river was also monitored for the presence of Salmonella sp. Only one positive isolation was achieved during this study, and this isolate was characterized as being Salmonella alachua. 相似文献
10.
M M Kozlovskaia A N Kharlamov K S Raevski? A V Val'dman 《Biulleten' eksperimental'no? biologii i meditsiny》1981,91(1):45-48
The development of the tranquilizing effect of n-dipropylacetate (n-DPA) selectively increasing the GABA level in the nerve terminals was studied in experiments on cats in comparison with diazepam effect. The changes in the spectrum of emotional-behavioral reactivity were estimated. In doses of 50 and 200 mg/kg n-DPA caused a marked antiphobic effect which was not accompanied by the activating component characteristic of diazepam. The n-DPA-induced increase in the GABA level in the nerve terminals is suggested to be important for the development of the anxiolytic effect of tranquilizers. The total increase in the GABA level in the nerve terminals is suggested to be important for the development of the anxiolytic effect of tranquilizers. The total increase in the GABA content in the brain correlates to a greater extent with the sedative effect of drugs. 相似文献
11.
Experiments were conducted on awake rabbits to which trifluoperazine was given daily for 2 weeks in a dose of 1 mg/kg a day; a study was made of the reaction of the cortical neurones in response to the electrostimulation of its adjacent areas. In measuring the dispersions of the poststimular histograms it was found that under the effect of trifluoperazine there occurred a reduction of the value and the duration of the responses of the cortical neurons after the infliction of stimulation. The effect obtained after the administration of trifluoperazine was regarded from the point of view of aggravation of the signal conduction in the neuronal reticula. 相似文献
12.
The effect of estradiol on adrenal secretion rate of cortisol in response to a stress induced by anesthesia, was examined by comparing the metabolic clearance rate and the production rate of cortisol between males and females and after estradiol administration in castrated animals. Metabolic clearance rates of cortisol (MCR) were significantly higher (+30%) in males than in females. Castration lowered the MCR of cortisol in males and had no significant effect in females. After estradiol administration, a fall in the MCR of cortisol concomitant with a rise in blood cortisol level was observed especially in males in which the effect of treatment was more marked than in females and highly significant. The production rate of cortisol was identical in males and females and was slightly increased in estradiol-treated males and females. The data indicate that estradiol had an inhibitory effect on metabolic clearance of cortisol, which caused an important rise of blood cortisol levels in response to stress and which prevented an increase in the adrenal response to the stress. Since the pituitary adrenal cortex can respond in a normal way to stress, the low value of MCR of cortisol could be the limiting factor in the adrenal secretion rate of cortisol in estrogen-treated guinea-pigs. 相似文献
13.
家蚕茧质性状的性别效应预测 总被引:5,自引:0,他引:5
研究采用混合线性模型,对家蚕全茧量、茧层量、茧层率和蛹体重等性状的性别效应进行理论估算:全茧量、茧层量、茧层率和蛹体重等4性状的性别随机效应的方差的概率和性别随机效应的预测值概率都达到极显著水平,证明全茧量、茧层量、茧层率和蛹体重等四性状的性别效应极显著,这完全符合实际情况。全茧量、茧层量、茧层率和蛹体重等4性状的性别效应预测值雌(雄)分别为0.248g(-0.247g)、2.423cg(-2.394)cg、-1.976%(1.992%)和0.224g(-0.223g)。性别效应调整后各性状均呈单峰正态分布,符合QTL分析对数量性状连续正态分布的要求。 相似文献
14.
The role of serotonin receptors in the inhibitory effect of serotoninergic system on immunogenesis was studied using cyproheptadine, a specific blocker of 5-HT2 receptors. It was shown that cyproheptadine administration to CBA mice stimulated the immune response, which was dopamine-dependent and was realized via thymus. With the pituitary stalk destruction, the stimulatory effect of cyproheptadine was not observed, which suggests the participation of 5-HT2 brain receptors in immunogenesis. 相似文献
15.
The inactivation of wild-type yeast Saccharomyces cerevisiae was studied after simultaneous treatment with ultrasound and hyperthermia. A temperature range was established within which ultrasound and hyperthermia exert a synergistic action. The effect was shown to depend on ultrasound intensity and the temperature at which the treatment takes place. The temperature range enhancing the ultrasound effect shifted forward higher temperature with increasing ultrasound intensity. For every intensity value, an optimal temperature exists at which the synergetic effect is maximum. The biophysical interpretation of the results obtained is based on the assumption that synergism is due to an additional lethal damage, which arises from the interaction of some sub-lesions induced by both agents. These sublesions are considered non-lethal if the agents are applied separately. 相似文献
16.
Nakipova O. V. Averin A. S. Zakharova N. M. Uchitel M. L. Grishina E. V. Bogdanova L. A. Maevsky E. I. 《Biophysics》2010,55(6):1019-1024
The effect of ambiocor (15 mg/100 ml), which contains natural substrates of energy metabolism, on the contractility of papillary
muscle of the right ventricle of rat heart was studied at stimulation frequencies from 0.1 to 3.0 Hz at a temperature of 30
± 1°C (n = 7). The effect was recorded 20 min after the addition of the preparation. It was demonstrated that ambiocor causes a significant
(about 70%), independent of stimulation frequency, suppression of the amplitude of isometric contractions (negative inotropic
effect), which is coupled with an increase in the relative value of the rest potentiation effect (a qualitative index of calcium
content in SR). The influence of the mixture leads to significant alterations in the time parameters of the “contraction-relaxation”
cycle: an increase in the duration of latent period; and a decrease in the time to peak tension and half-relaxation time.
The effect of the mixture is partially reversible. During washing off the preparation with the control solution, the qualitative
indicators of the contractile activity of papillary muscle are substantially improved in comparison with the initial ones.
The character of alterations allows one to assume that the effect of ambiocor in the papillary muscle of the rat heart is
realized partly through the suppression of the activity of sarcolemmal calcium channels. 相似文献
17.
Isometric contraction time (CT), half relaxation time (1/2 RT), tetanus fusion frequency (TFF) and tetanus: twitch ratio (T : t ratio) were measured in the denervated (D) and tenotomized-denervated (TD) Soleus muscle of the rat. In D muscle there was an apparent speeding effect at the 2nd day after denervation, with a significant decrease of CT, which was followed by the usual slowing process of denervated muscle. In TD muscle, denervation was performed a week after tenotomy. Tenotomy "per se" was ineffective in modifying dynamic properties of muscle, but it accentuated the early shortening of CT caused by denervation, while reducing and delaying the subsequent slowing process. The results are discussed in the light of the hypothesis that muscle disuse has a speeding effect which counteracts the slowing effect of denervation, and/or that tenotomy modifies the effects of denervation by changing the pattern of fibrillation development. 相似文献
18.
The amino acid arginine is frequently used as a solution additive to stabilize proteins against aggregation, especially in the process of protein refolding. Despite arginine's prevalence, the mechanism by which it stabilizes proteins is not presently understood. We propose that arginine deters aggregation by slowing protein-protein association reactions, with only a small concomitant effect on protein folding. The associated rate effect was observed experimentally in association of globular proteins (insulin and a monoclonal anti-insulin) and in refolding of carbonic anhydrase. We suggest that this effect arises because arginine is preferentially excluded from protein-protein encounter complexes but not from dissociated protein molecules. Such an effect is predicted by our gap effect theory [Baynes and Trout (2004) Biophys. J. 87, 1631] for "neutral crowder" additives such as arginine which are significantly larger than water but have only a small effect on the free energies of isolated protein molecules. The effect of arginine on refolding of carbonic anhydrase was also shown to be consistent with this hypothesis. 相似文献
19.
Morphine injected into the rat cerebral ventricles had a marked analgesic effect, while no effect was observed with pentazocine and naloxone or nalorphine caused a strong hyperalgesia. Administered systemically (IP) naloxone and nalorphine caused a transitory analgesia followed by a long lasting hyperalgesic effect; morphine and pentazocine showed only an analgesic effect. It was concluded that the site of analgesic action of opioid-antagonists is peripheral rather than central. The peptidase-resistant enkephalin-analog, BW 180c, which does not cross the blood brain barrier, caused a marked analgesia by IP administration to paws made hyperalgesic by PGE2 or carrageenin. It is suggested that agents derived from morphine, morphine-antagonists, enkephalins or cGMP devoid of central effect but having a strong peripheral effect may constitute a new class of safer analgesics. 相似文献
20.
Hiroki Fujiwara Kosuke Sawa Muneyoshi Takahashi Johan Lauwereyns Minoru Tsukada Takeshi Aihara 《Cognitive neurodynamics》2012,6(5):399-407
An extinguished conditioned response can sometimes be restored. Previous research has shown that this renewal effect depends on the context in which conditioning versus extinction takes place. Here we provide evidence that the dorsal hippocampus is critically involved in the representation of context that underscores the renewal effect. We performed electrolytic lesions in dorsal hippocampus, before or after extinction, in a conditioned taste aversion paradigm with rats. Rats that underwent all conditioning, extinction and testing procedures in the same experimental context showed no renewal during testing in the original context. In contrast, rats that underwent extinction procedures in a different experimental context than the one in which they had acquired the conditioned response, showed a reliable renewal effect during testing in the original context. When electrolytic lesion was performed prior to extinction, the context-dependent renewal effect was disrupted. When electrolytic lesion was undertaken after extinction, we observed a complex pattern of data including the blockage of the conventional renewal effect, and the appearance of an unconventional renewal effect. The implications of these results are discussed with respect to current views on the role of the dorsal hippocampus in processing context information. 相似文献