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61.
Guard honeybees stand at the entrance of colonies and facilitate the exclusion of nonnestmates from the colony. In this study, we examined the hypothesis that genetic variability among individuals in colonies might explain variability in guarding activity. To do this, we cross-fostered honey bees between colonies with high-defensive responses and colonies with low-defensive responses in alarm pheromone tests. Individuals from high-defensive colonies were more likely to guard in their own colonies (controls) than cross-fostered bees from low-defensive colonies. Cross-fostered high-defensive bees also were more likely to guard in low-defense colonies. These results support the hypothesis that interindividual differences in guarding behavior are at least partially under genetic control. A positive correlation between number of guards and response to alarm pheromone demonstrates a link between behaviorally separated components of the overall defensive response.This work was supported by NSF Grant BNS 8605604.  相似文献   
62.
Objectives: To determine the incidence of alcohol use in subcritically injured patients presenting to the ED, by using a saliva alcohol test (SAT) at ED triage during the ED initial assessment; to compare the incidence of alcohol use revealed by the SAT with documentation of alcohol use by ED nurses and emergency physicians (EPs) blinded to the SAT results; and to describe the demographics of the SAT-positive, subcritically injured population.
Methods: A blinded, prospective, observational evaluation of ED patients presenting with subcritical injuries was performed. The patients were tested for alcohol use with an SAT, and a subsequent record review was conducted for extraction of demographic data and evidence of documentation of alcohol use by ED nurses and EPs blinded to the SAT results.
Results: During the study. 791 subcritically injured patients had SATs performed. Twenty-one percent of these patients were found to be alcohol-positive by SAT. Either the ED nurse or the EP documented a clinical impression of alcohol use for 52% of the SAT-positive patients. There were higher SAT-positive rates among men (24%), victims of assault (47%), and patients arriving at night (41%).
Conclusions: While the SAT identified 21% of the subcritically injured patient population as alcohol-positive, ED nurse and EP documentation did not identify half of these alcohol-positive patients. Many of these patients may be at risk for additional injuries related to their drinking behavior.  相似文献   
63.
The effects of oral contraceptive administration on the social relationships of adult female cynomolgus monkeys (Macaca fascicularis) were examined. Ten females were administered ethinyl estradiol/ethynodiol diacetate (Demulen), 10 were administered ethinyl estradiol/norgestrel (Ovral), and 10 served as a control group. The monkeys lived in social groups of 5 females each, and patterns of social interaction and social status were recorded. Interfemale relationships were also observed when a vasectomized male was placed in each social group for 50 min, once/week. During the latter observations, preliminary data on the effects of oral contraceptive treatment on sexual interaction were also collected. In the absence of the male, interfemale agonistic interactions and time spent alone were influenced by social status but not by oral contraceptive treatment. Time spent in passive body contact, an affiliative state, was reduced by Ovral treatment. In the presence of the male, dominant females aggressively interfered with the sexual interactions of subordinates. This aggression resulted in the termination of a greater proportion of the sexual interactions of subordinates than dominants in the control group only, indicating suppression of this type of interaction by oral contraceptive treatment. Other effects included a decreased frequency of ejaculation with Ovral-treated females. These results suggest that oral contraceptives may suppress certain types of female agonistic behavior (e.g., in the context of mate competition) and some oral contraceptives may interfere with sexual activity. More broadly, these findings indicate that intrasexual competition for access to mates may occur in females as well as males. This study was supported in part by NICHD Contract #N01-HD-32800 and by Grant #HL14164 from the National Heart, Lung and Blood Institute.  相似文献   
64.
This study investigated a discrete-trial, titration duration discrimination procedure in behavioral pharmacology. Pentobarbital and d-amphetamine, measured with this procedure, selectively affected discrimination more than response tendencies. Pentobarbital also tended to affect selectively discrimination of longer durations, whereas d-amphetamine did not. Further experiments showed that (1) other algorithms for modulating stimulus duration are useful in behavioral pharmacology and toxicology, (2) threshold estimates are similar with the method of constant stimuli and the method of titration, and (3) this titration procedure permits the separate examination of drug effects upon discrimination and upon response tendencies; the fixed-interval procedure does not. Baseline variability was an important correlate of drug effects in that the endpoints with more variable baselines were also more sensitive to drugs.  相似文献   
65.
The validity of a self-administered diet history questionnaire has been estimated using as the reference data the mean of three 4-day diet records collected over the year prior to the administration of the questionnaire, in 1985–1986. Subjects were women ages 45–70 years, participants in the Women's Health Trial Feasibility Study, a multi-center clinical trial in which some women were randomized to be taught to adopt and maintain a low-fat diet, while others maintained their usual diet. The questionnaire produced group mean nutrient estimates closely approximating the values obtained by three 4-day records, e.g. in the usual-diet group, 37.7% of calories from fat by both food records and by questionnaire, and in the low-fat, group, 21.3% of calories from fat by food records and 23.7% of calories from fat by questionnaire. Correlations between questionnaire and diet records for per cent of calories from fat were 0.67 and 0.65 respectively in the two groups; most correlations were in the 0.5–0.6 range, and were similar to those achievable by a single 4-day food record.  相似文献   
66.
67.
Research Institute of Experimental Pathology and Therapy, Sukhumi. (Presented by Academician of the Russian Academy of Medical Sciences B. A. Lapin.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 114, No. 11, pp. 457–459, November, 1992.  相似文献   
68.
The moderator effect of gender on (i) the relation between adolescents' sexual experience on the one hand; and (ii) their orientations towards the type of relational and emotional commitment that they expect to be present before engaging in a sexual relationship, and (iii) having a steady partner on the other was examined. We hypothesized that the relations between these facets would be stronger for women. We utilized a random sample of 253 British adolescents interviewed twice with a 1-year interval LISREL multigroup analysis with mean structures was used to test the hypotheses, thus offering the opportunity of detecting moderator as well as main effects of gender. Differential effects of emotional and relational commitment and having a steady partner relationship on sexual experience supported the hypotheses.  相似文献   
69.
The study examined predictors of children's prosocial responses to adult negative emotions. An adult displayed anger, sadness and pain during play sessions with 39 preschoolers (mean age = 43 months). Older children responded more prosocially to all three emotions, whereas children with greater emotion knowledge responded more prosocially to the adult's sadness. Children who behaved prosocially in response to peers' negative emotions also were prosocial after the adult's negative emotions, even with effects of age and emotion knowledge held constant. Assertive children responded more prosocially to the adult's anger, even with effects of other variables held constant. Both theoretical and practical implications are discussed.  相似文献   
70.
饮食习惯与肺癌关系的病例—对照研究   总被引:10,自引:1,他引:9  
钟礼杰  高玉堂 《肿瘤》1995,15(6):438-443
为探明上海市女性非吸烟者肺癌与饮食习惯的关系,作者于1992年2月1日 ̄1993年12月31日在上海市区开展了一项基于全人群的病例对照研究,共调查非吸烟女性肺癌新发病例504例和按频数配对的年龄相差5岁以内的女性非吸烟对照601人。在调查了年龄、经济收入等因素后,发现蔬菜、水果和β-胡萝卜素、维生素C等营养素的摄入量与肺癌危险性呈负相关,线性趋势均有显著性。与最高摄入组相比,蔬菜、水果、β-胡萝卜  相似文献   
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