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61.
女护士生性教育现状及需求的调查分析   总被引:2,自引:0,他引:2  
本研究以大连某卫校女护士生为研究对象,采用自编式问卷对女护士生的性教育现状及需求进行了调查分析.结果表明:卫校女生在性知识、性态度、性行为方面发展的主流是好的、健康的,但也有少数女护士生对自身正常的性生理、性心理现象不了解而产生心理困惑和压力,女护士生渴望从学校得到正规的性教育.为了使女护士生身心得到健康发展,学校必须开展以性道德教育为核心的正规的性教育.  相似文献   
62.
The aim of this study was to examine the effects of histaminergic antagonists on memory upon injection into the region of the nucleus basalis magnocellularis (NBM). In experiment 1, rats with chronically implanted cannulae were trained on the uphill avoidance task, which involves a punishment of a high-probability turning response on a tilted platform (negative geotaxis). Immediately after the training trial, that is, after a tail shock was administered upon performing the response, rats received one microinjection (0.5 microliter) of H1-receptor blocker chlorpheniramine (dose range 0.1 to 20 microgram) or the H2-receptor blocker ranitidine (same dose range) or saline into the NBM region. When tested 24 h later, rats treated with chlorpheniramine (20 micrograms) had significantly longer uphill latencies than vehicle controls and ranitidine-treated animals, indicative of superior learning of the avoidance response. In experiment 2, a test for possible proactive effects of posttrial chlorpheniramine on performance during the retention trial was performed. Animals were injected with either 20 micrograms chlorpheniramine or saline immediately after the training trial of the uphill task. One chlorpheniramine control group was treated with a delay of 5 h. Additional groups which received chlorpheniramine or vehicle after the training trial but no trail shock were included. When tested 24 h later, rats injected with 20 micrograms chlorpheniramine again exhibited significantly longer uphill latencies than did vehicle-injected rats. Retention latencies for the rats of the chlorpheniramine 5-h delayed group did not differ from those of the vehicle-injected rats, ruling out proactive effects of chlorpheniramine on performance. In summary, the histaminergic H1-blocker chlorpheniramine can enhance mnemonic functioning in addition to its reinforcing effects upon NBM injection as reported previously.  相似文献   
63.
Intraspecific communication between mice takes place mainly via urinary chemosignals or "pheromones". Pheromones can influence aggressive and reproductive behavior as well as the neuroendocrine condition of the recipient female mice via their olfactory system. In this study, reproductively cyclic mice in the estrus phase were used to test intraspecific agonistic aggressive behavior. Data were obtained also on the count of the eggs shed in the oviducts. The results showed that (i) individually housed female mice are more aggressive toward an intruder female mouse than grouped mice, (ii) mice in which the vomeronasal organ was removed show aggressive behavior intermediate between individually housed and grouped mice, and (iii) a within group analysis did not show a positive correlation between aggression and presence of shed eggs in the oviducts.  相似文献   
64.
The relation between reinforcer magnitude and timing behavior was studied using a peak procedure. Four rats received multiple consecutive sessions with both low and high levels of brain stimulation reward (BSR). Rats paused longer and had later start times during sessions when their responses were reinforced with low-magnitude BSR. When estimated by a symmetric Gaussian function, peak times also were earlier; when estimated by a better-fitting asymmetric Gaussian function or by analyzing individual trials, however, these peak-time changes were determined to reflect a mixture of large effects of BSR on start times and no effect on stop times. These results pose a significant dilemma for three major theories of timing (SET, MTS, and BeT), which all predict no effects for chronic manipulations of reinforcer magnitude. We conclude that increased reinforcer magnitude influences timing in two ways: through larger immediate after-effects that delay responding and through anticipatory effects that elicit earlier responding.  相似文献   
65.
This experiment examined the relationship between reinforcer magnitude and quantitative measures of performance on progressive‐ratio schedules. Fifteen rats were trained under a progressive‐ratio schedule in seven phases of the experiment in which the volume of a 0.6‐M sucrose solution reinforcer was varied within the range 6–300 μl. Overall response rates in successive ratios conformed to a bitonic equation derived from Killeen's (1994) Mathematical Principles of Reinforcement. The “specific activation” parameter, a, which is presumed to reflect the incentive value of the reinforcer, was a monotonically increasing function of reinforcer volume; the “response time” parameter, δ, which defines the minimum response time, increased as a function of reinforcer volume; the “currency” parameter, b, which is presumed to reflect the coupling of responses to the reinforcer, declined as a function of volume. Running response rate (response rate calculated after exclusion of the postreinforcement pause) decayed monotonically as a function of ratio size; the index of curvature of this function increased as a function of reinforcer volume. Postreinforcement pause increased as a function of ratio size. Estimates of a derived from overall response rates and postreinforcement pauses showed a modest positive correlation across conditions and between animals. Implications of the results for the quantification of reinforcer value and for the use of progressive‐ratio schedules in behavioral neuroscience are discussed.  相似文献   
66.
研究了条件反射性抗体反应增强模型的建立。被试为49只雄性成年Wistar大鼠,采用糖精水作为条件性刺激,一种蛋白抗原卵清蛋白作为非条件性刺激配对给予大鼠,两者结合后,在初次抗体应答下降阶段再次单独给予条件刺激,用酶联免疫吸附法分时段检测抗体水平的变化。发现条件组在条件刺激后15,20,25天左右抗体水平明显高于对照组。这一过程与初次抗体应答的规律类似。这些结果证实经一次条件训练,单独给予条件刺激能诱导出明显的条件反射性抗体反应增高。  相似文献   
67.
Although research into the factors that may affect male achievement of political leadership is relatively robust, very few studies on the making of female presidents and prime ministers exist. This paper examines the literature on birth order, sex of siblings, and parent-daughter dynamics to see whether the findings for male political leaders—that first-born individuals will be overrepresented as compared with later-born siblings—also hold for female ones. Two other hypotheses were tested concerning differences in birth order and sex of siblings between female political leaders and a larger sample of women. A review of the literature on parent-daughter dynamics suggests that this may be another important variable for future research into explanations for the success of women who achieve senior-level positions of power. The findings suggest that first-born women, like first-born men, are overrepresented among political leaders; that first-born women are overrepresented among female political leaders as compared with their numbers in a larger sample population; and that fewer female political leaders have an older brother than would be expected to occur in a larger sample population. The last finding applies only for women who come to power in the period 1960–1989, not those who gained office more recently.  相似文献   
68.
Periods of 24 to 48 hours of food deprivation reliably induced pup-killing in 30–50% of non-killer male mice. The behavior was prevented by previous experience with young and did not perseverate to non-deprived states. Castrated males and intact females also exhibited pup-killing following food deprivation, suggesting that the behavior is neither sexdependent nor related to the presence of testosterone. The findings are discussed in terms of their relationship to predatory behaviors and population dynamics.  相似文献   
69.
Two aspects of the amygdaloid complex (corticomedial and basolateral) were examined with reference to serotonergic inhibition of shock-induced aggression. Fighting was significantly depressed by serotonergic stimulation (5-HT, 10 μg bilateral) in the corticomedial amygdala while serotonergic blockade (methysergide, 5 μg bilateral) in this region increased levels of fighting. No consistent effects were obtained with serotonergic manipulation of the basolateral amygdala. Further investigation revealed that the state of serotonergic activity in medial amygdaloid sites was associated with concomitant alterations in the animals' sensitivity to footshock. Results are discussed in relation to a) a general inhibitory role of serotonin in behavioural mechanisms and b) a dopaminergic-serotonergic balance for behavioural arousal involving medial amygdaloid nuclei.  相似文献   
70.
Forty-six female mice (CFW) were isolated for a period of 23 weeks. The effect of isolation on fighting behavior was tested weekly by introducing a naive brown female mouse into the subject's home cage. Total leucocyte counts were obtained at 8 and 14 weeks of isolation. The appearance of leucopenia was used as an index of elevated adrenocortical activity. After 23 weeks of isolation all animals were sacrificed by decapitation. Plasma was collected for corticosterone assay, and paired adrenals were used to assay catecholamine levels. On the basis of the frequency and/or the absence of fighting, the mice were segregated into fighters (n = 22) and non-fighters (n = 17). Analysis of the data by Pearson's product moment correlation and Student's t-test showed that elevated sympathetic-adrenal activity was positively correlated with aggression and that elevated adrenocortical activity was negatively correlated with aggression.  相似文献   
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