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81.
The present study was designed to investigate the chemical properties of the aggression-promoting cues present in bladder urine of male mice. The results of the first experiment confirmed earlier work by demonstrating the presence of an aggression-promoting chemosignal in bladder urine. In Experiment 2, behavioral assays were separately performed on the organic and aqueous layers of bladder urine obtained by repeated dichloromethane extractions. Only the combined organic layers of the initial three extractions demonstrated behavioral activity. A fourth extraction showed no behavioral activity for both organic and aqueous layers. However, the findings of Experiment 3 showed that incubation of the aqueous layer from the third CH2Cl2 extraction in β-glucuronidase can free additional aggression-promoting cues into a subsequent CH2Cl2 extraction. It is concluded that two forms of the aggression-promoting chemosignal are present in bladder urine. One is lipophilic and behaviorally active, whereas the other is conjugated, possessing latent chemosignal properties.  相似文献   
82.
We describe a surgical procedure for optimizing the location of telemetry ECG leads in rats. The new location was aimed at obtaining an accurate representation of ECG features throughout the cardiac cycle by limiting the voltage instability usually observed during intense somatomotor activity and improving the signal-to-noise ratio. The two electrodes (wire loops) were fixed on the dorsal surface of the xiphoid process and in the anterior mediastinum close to the right atrium. The implantation procedure was fast, little invasive, and allowed animals to completely recover from intervention. The performance of the “improved” location (IL, n = 10) with respect to two subcutaneous (SC) positionings (“conventional positioning,” CSP, n = 5; “updated location,” USL, n = 5) was evaluated by comparing ECGs obtained in baseline, stress and recovery conditions and during different behavioral activities (immobility and grooming). The resident-intruder test (emotional/physical challenge) was chosen as experimental stress paradigm. The noise level of ECGs obtained from IL rats was lower than in CSP and USL animals, in all recording conditions. Percentages of correctly recognized beats (CRBs) over the total number of beats (TBs) were significantly higher in IL rats than in CSP and USL animals, both in baseline conditions (99% vs. 11% and 40%) and situations involving high somatomotor activity (stress: 97%, 5% and 16%; recovery: 97%, 7%, and 15%) (p < 0.01). The performance of IL as compared to CSP and USL was also better when percentages during grooming and immobility were considered (grooming: 93% vs. 4% and 23%; immobility: 97%, 6%, and 33%; p < 0.01).  相似文献   
83.
目的探讨小学教师主观幸福感与社会支持、应对方式的关系。方法采用主观幸福感指数量表、领悟社会支持量表和简易应对方式问卷对152名小学教师进行问卷调查。结果社会支持各维度、积极应对方式与主观幸福感各维度之间的相关均有显著意义。结论社会支持、积极应对方式是影响小学教师主观幸福感的重要因素。  相似文献   
84.
大学生寻求专业性心理帮助态度的预测因素研究   总被引:2,自引:0,他引:2  
目的:探讨大学生寻求专业性心理帮助态度的预测因素。方法:选取700名不同年级、不同专业的大学生作样本,进行问卷调查。结果:以寻求专业性心理帮助态度为因变量,进行性别(2)×专业(2)的方差分析。结果发现,性别的主效应显著,F(1,615)=3.294,P=0.050。专业的主效应显著,F(1,615)=20.896,P=0.001。性别和专业的交互效应没达到显著性水平,F(1,615)=1.890,P=0.170。以寻求专业性心理帮助态度为因变量,回归分析结果得出R=0.636,R2=0.405,F=29.641,P=0.001,说明建立的回归方程是有意义的。结论:①对寻求专业性心理帮助态度有显著预测作用的变量按预测作用大小排序依次是:是否求助过、依赖的自我结构、自我隐藏度、专业、内控性和性别。②女生的寻求专业性心理帮助的态度比男生积极。③文体艺术类学生的寻求专业性心理帮助的态度比非文体艺术类学生积极。④自我结构是相互依赖的人寻求专业性心理帮助的态度积极。⑤自我隐藏度高的人寻求专业性心理帮助的态度消极。⑥内控者寻求专业性心理帮助的态度消极。  相似文献   
85.
3,4-methylenedioxy-methylamphetamine (MDMA) (‘Ecstasy’) and its analogue 3,4-methylenedioxy-methylamphetamine (MDE) (‘Eve’) are well known illicit street drugs mainly abused by young people. In spite of the actual research going on, the classification of their abuse potential remains unclear. Since secondary reinforcers are the main factors responsible for craving and relapse, the aim of our study was to assess the potency of MDMA and MDE in a second order reinforcement paradigm, i.e. conditioned place preference (CPP). For the general assessment of our study conditions, we compared MDMA with amphetamine. Unexpectedly, no significant CPP for MDMA was found in contrast to amphetamine. Detailed analysis of current literature led us to the working hypothesis that social environment is crucial for the development of CPP. In a subsequent experiment we tested the influence of housing conditions on CPP using MDMA and demonstrated that isolated animals show significant CPP compared to group-housed ones. In order to better understand the rewarding mechanisms of Ecstasy-derivatives, we tested both the racemic drugs and the pure isomers in the CPP paradigm. Both MDMA's optical isomers and racemic MDMA showed significant CPP without notable differences, while MDE and its isomers completely failed to show any significant CPP. In conclusion, the mechanism by which MDMA induces addiction is much more complicated than assumed so far and more pronounced in isolated animals. The fact that both optical isomers of MDMA led to CPP implies that at least two pathways by which MDMA induces craving behaviour exist.  相似文献   
86.
There have been contradictory findings in the fragile X (fraX) literature about possible neurocognitive and psychological symptoms due to the fraX premutation (pM). The purpose of the present study was to investigate the relationship between CGG repeat length and neurobehavioral functioning in carriers of the fraX pM. Eighty‐five female carriers of the pM with allele sizes ranging from 59–166 were administered a comprehensive IQ test (WAIS‐III) and completed a questionnaire designed to measure psychopathology (Symptom Checklist (SCL)‐90‐R). No relationship between allele size and cognition was identified. A significant negative relationship between allele size and age was found, as well as a positive relationship between allele size and depression. Follow‐up analyses separating small and large allele sizes (below and above 100 CGG repeats) indicated that individuals with larger allele sizes scored significantly higher on the Interpersonal Sensitivity and Depression subscales of the SCL‐90‐R. Despite the limitation of few individuals with high CGG repeat lengths, our findings suggest that females with larger premutated alleles (≥ 100 repeats) display some clinical manifestations of fraX syndrome. © 2001 Wiley‐Liss, Inc.  相似文献   
87.
Considered threats to validity and generalizability of psychologicalresearch with pediatric populations and proposed ways to betterunderstand and manage these problems. Variation due to characteristicsof acute and chronic conditions (e.g., duration, severity, illnesscourse), settings and referral patterns, family environmentalcharacteristics, as well as investigators' decisions concerningcriteria and recruitment limit inferences concerning the impactof pediatric conditions on psychological development and generalizabilityof findings. These problems call for an expanded use of replication,cross-center, population-based, and theory-driven research.Scientific progress will be made by increasing dialogues andcollaboration among researchers concerning generalizabilityproblems and improving research training in epidemiologicalmethods, analysis of large-scale data sets, and meta-analysis.  相似文献   
88.
This study examined two groups of people who were pursuing treatment for obesity: either medical intervention (a hospital group; N = 20) or support for dietary restriction (a community group; N = 18). This study addressed four questions: (1) Were there differences between the two groups in terms of their psychological distress (as measured by the Symptom Checklist)? (2) Does binge eating moderate psychological distress? (3) Do feelings of ineffectiveness moderate psychological distress? and (4) Which variables best accounted for group membership (i.e., type of treatment sought)? Results suggested that the hospital group was significantly more distressed than the community group. However, there were no differences between the two groups with respect to binge eating or feelings of ineffectiveness. These findings suggest that it is the effects of morbid obesity that are most likely to moderate psychological distress.  相似文献   
89.
Psychological distress in high-risk youth with asthma   总被引:5,自引:0,他引:5  
OBJECTIVE: To examine the relationship between asthma and psychological distress among adolescents already at-risk for adjustment problems secondary to lower economic strata and educational or vocational failure. METHOD: Twenty-five high-risk adolescents with asthma and 25 high-risk controls without asthma 16 to 21 years old completed the Brief Symptom Inventory, the Beck Depression Inventory, and the Beck Anxiety Inventory. RESULTS: Adolescents with asthma had significantly higher scores on multiple measures of psychological distress. Specifically, adolescents with asthma evidenced higher levels of anxiety, depression, and global psychological distress than those without asthma. CONCLUSIONS: High-risk adolescents with asthma may be more likely to experience psychological distress than those without asthma. Our findings suggest that asthma constitutes an additional significant independent stressor or risk factor among adolescents who already are at high risk for multiple adjustment problems.  相似文献   
90.
吸毒者的社会支持及与心身健康水平的相关分析   总被引:1,自引:3,他引:1  
毒品滥用已成为严重社会问题 ,并已引起医学界、心理学界及社会各界的关注。吸毒者的吸毒行为除与他们自身心理特征有关外 ,还与许多因素有关。如失业、缺乏家庭温暖、精神空虚、孤独 ,对生活失去热情和信心等。研究认为 ,社会支持系统不良是导致多种心理卫生问题的重要原因之一 ,也是吸毒成瘾及复吸的主要原因[1,2 ] 。本研究运用社会支持量表和症状自评量表对一组吸毒者的社会支持状况及与心理健康的关系作初步研究 ,旨在为吸毒者实施心理治疗及作戒毒后回归社会的跟进服务提供参考。1 资料与方法1.1 调查对象1.1.1 吸毒组 选择长沙市…  相似文献   
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