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91.
Rationale: Impulsivity is implicated in drug dependence. Recent studies show problems with alcohol and opioid dependence are associated with rapid discounting of the value of delayed outcomes. Furthermore, discounting may be particularly steep for the drug of dependence. Objectives: We determined if these findings could be extended to the behavior of cigarette smokers. In particular, we compared the discounting of hypothetical monetary outcomes by current, never, and ex-smokers of cigarettes. We also examined discounting of delayed hypothetical cigarettes by current smokers. Methods: Current cigarette smokers (n=23), never-smokers (n=22) and ex-smokers (n=21) indicated preference for immediate versus delayed money in a titration procedure that determined indifference points at various delays. The titration procedure was repeated with cigarettes for smokers. The degree to which the delayed outcomes were discounted was estimated with two non-linear decay models: an exponential model and a hyperbolic model. Results: Current smokers discounted the value of delayed money more than did the comparison groups. Never- and ex-smokers did not differ in their discounting of money. For current smokers, delayed cigarettes lost subjective value more rapidly than delayed money. The hyperbolic equation provided better fits to the data than did the exponential equation for 74 out of 89 comparisons. Conclusions: Cigarette smoking, like other forms of drug dependence, is characterized by rapid loss of subjective value for delayed outcomes, particularly for the drug of dependence. Never- and ex-smokers could discount similarly because cigarette smoking is associated with a reversible increase in discounting or due to selection bias. Received: 3 March 1999 / Final version: 11 May 1999  相似文献   
92.
This article presents findings from a survey of programmes available for tobacco and alcohol users working in 455 of Australia's top 600 companies. Companies were twice as likely to have programmes for smokers (43%) as for problem drinkers (24%) and these programmes were more apparent in large companies. The majority of programmes for smoking were delivered within a health promotion context which included other life-style issues, such as nutrition, exercise, weight management and stress management. Although Employee Assistance Programs (EAPs) were the most commonly available type of work-place programme for excessive drinkers and other drug users, followed by Alcoholics Anonymous and local hospital clinics, only 6% had an EAP for alcohol. Only 21% of programmes for smokers and 12% for excessive alcohol users were evaluated. Around one-quarter of companies knew the costs of smoking programmes, and 9% reported costs of conducting programmes for excessive alcohol consumers.  相似文献   
93.
A series of studies on sexual abuse prevention are presented to highlight important clinical and research issues. In a multi-modal evaluation conducted by the author, elementary children who participated in three group sessions using the Feeling Yes, Feeling No prevention program increased significantly in knowledge and the ability to discriminate unsafe from safe situations. Gains were maintained over a one-year follow-up period. Approximately 5% of the children disclosed sexually abusive experiences. Participating children also exhibited no more anxiety or behavior problems after the program than control children. A second study evaluated the relative efficacy of prevention programs for children conducted by teachers vs. expert consultants. Children in each trainer condition demonstrated equivalent knowledge gains and made equivalent numbers of disclosures. Clinical research by other authors is reviewed to highlight important issues in prevention groups with preschoolers and adolescents, the impact of prevention education on feelings about sexuality, and behavioral effects of prevention programs. Finally, the incorporation of prevention education into psychotherapeutic groups for child victims is discussed.  相似文献   
94.
The relationships between five potential indicators of alcohol-related harm following drinking on licensed premises in Perth were explored. These were annual purchases made by individual licensees of 'high' (>=3.8%) and 'low' (<3.8%) alcohol content drinks, the number of times a particular licensed establishment is cited by drivers as the last place of drinking prior to failing a roadside breath-test (including after accidents) and the annual number of assaults occurring either on or in the vicinity of particular licensed premises. The study area selected was a central part of the Perth metropolitan area with 367 licensed premises serving a residential population of 400 000. Highly significant correlations were found between each of the five variables. The correlations involving purchases of low alcohol drinks, however, were small. When purchases of alcohol were controlled, significant, though lower, correlations, were still evident between the other three variables. This suggests that there are risk factors other than extent of alcohol sales which further research will need to identify, and that these indicators of harm can be of value in monitoring the impact of future intervention strategies.  相似文献   
95.
Depression and anhedonia are two major symptoms of cocaine withdrawal in humans. Hence, pharmacological treatments effective in depression might also alleviate the symptoms of cocaine withdrawal. In the present study, the effects of acute and repeated administration of a tricyclic antidepressant, desmethylimipramine (DMI), were investigated in naive and cocaine-withdrawing rats. An animal model of cocaine withdrawal was used that employs the elevation in intracranial self-stimulation (ICSS) thresholds following the termination of prolonged periods of cocaine self-administration as a measure of an animal's anhedonic state. The influence of chronic DMI treatment on-adrenergic receptor binding and affinity was also correlated with the behavioral signs of cocaine withdrawal. Neither acute nor repeated DMI treatment influenced reward functions in rats that were not undergoing cocaine withdrawal. However, repeated DMI treatment significantly down-regulated-adrenergic receptors, and shortened the duration of the post-cocaine anhedonia (elevation in thresholds). Furthermore, the magnitude of the-adrenergic receptor down-regulation correlated significantly with the degree of effectiveness of DMI treatment in reversing the post-cocaine anhedonia. However, chronic DMI treatment did reduce the amount of cocaine self-administered by the animals. The reversal of the post-cocaine anhedonia in this animal model of cocaine withdrawal by chronic DMI treatment demonstrates the potential usefulness of the model in identifying new pharmacotherapies for cocaine withdrawal. In addition, the results indicate that tricyclic antidepressants may be able to ameliorate some of the symptoms of cocaine withdrawal.  相似文献   
96.
The present paper aims to explore issues related to men within the context of seeking help for substance abuse. The male gender role is in conflict with help-seeking behaviour and with the fundamental principles of therapy, i.e. introspection, emotional expressivity and acknowledgement of difficulties. This creates a paradox for the male seeking psychological treatment and, it will be argued, particularly for the male substance abuser. It is argued that interventions which address the gender role and challenge men's perceptions of themselves are critical variables in the outcome of therapy, i.e. enabling them to make the necessary changes in order to promote psychological well-being. An examination of the male gender role in relation to intrapsychic issues and family systems will be followed by a brief discussion of therapeutic interventions. Some of the difficulties and issues confronted by workers who work with male substance abusers will be explored.  相似文献   
97.
Physical activities such as long-distance running can be habit forming and associated with a sense of well-being to a degree that justifies comparison with drug-induced addictive behaviours. To understand molecular similarities and dissimilarities controlling these behaviours in humans we compared the effects of running in running wheels to the effects of chronic cocaine or morphine administration on mRNA levels in brain reward pathways in the inbred Fischer and Lewis rat strains. These strains are both inbred from the Sprague-Dawley strain; Lewis rats display a higher preference towards addictive drugs and running than do Fischer rats. After chronic cocaine or running a similar increase of dynorphin mRNA in medial caudate putamen was found in the Lewis rat, suggesting common neuronal adaptations in this brain region to both cocaine and running. Fischer and Lewis rats both responded to cocaine with increased dynorphin mRNA levels in medial caudate putamen. However, only Lewis rats increased dynorphin mRNA after running, possibly reflecting the much higher degree of running by the Lewis strain as compared to the Fischer strain. Moreover, the running-induced upregulation of dynorphin mRNA was blocked by the opioid receptor antagonist naloxone. We suggest that running increases dynorphin mRNA by a mechanism that involves endogenous opioids. The voluntary wheel-running model in rats might be used to study natural reward and compulsive behaviours and possibly also to screen candidate drugs for treatment of compulsive disorders.  相似文献   
98.
Objectives: To characterize whether adult depressives with either bipolar or unipolar disorder differ in the prevalence of childhood sexual or physical abuse.

Method: The investigators reviewed data from patients who were evaluated over a 2-year period by a semi-structured clinical interview. In total, 333 cases with a bipolar or unipolar diagnosis were included in the present study.

Results: A childhood history of abuse, in particular sexual abuse, was significantly more frequent in bipolar subjects compared with unipolar subjects. Consistent with previous studies, women reported higher rates of sexual abuse than men, although no interaction by diagnosis was shown. Sexual abuse incidence in male samples was markedly dissimilar, with male bipolar subjects demonstrating a significantly increased rate of sexual abuse and combined sexual and physical abuse compared with unipolar male subjects.

Conclusion: The increased incidence of sexual abuse in women supports growing evidence of gender differences in sexual abuse among adult depressives. In contrast to literature reports, the finding that male bipolar patients have significantly increased rates of sexual abuse histories suggests differences in psychiatric depressive subgroups. This result may reflect the particular characteristics of our cohort (treatment resistant, privately insured, and educated). Further work will aid in characterizing sexual abuse prevalence in other male bipolar samples.  相似文献   
99.
目的:探讨多药耐药集团(MDR1)在小细胞肺癌化疗中的作用和地位,方法:采用逆转录-多聚酶链式反应技术(RT/PCR)和免疫细胞化学染色法,检测了32例(初治原发癌21例和复治转移癌11例)小细胞肺癌患者血液中的MDR1mRNA水平和多药耐药蛋白(P-170)的表达,并对两种方法进行了比较。结果:初治的原发癌MDR1基因阳性表达率为14.29%,P-170蛋白阳性表达为14.27%,复治转移癌的MDR1基因阳性表达率为72.73%,P-170蛋白阳性表达为63.64%(P<0.01),有显著性差异。MDR1的基因和蛋白两种而检测方法具有一定的一致性,以RT/PTR方法具有更强的敏感性,结论:复治转移癌组比初治组具有更普遍的抗药性,且主要是获得性抗药,MDR1基因表达可作为临床合理地制定化疗方案,预测化疗效果的重要参考指标。  相似文献   
100.
受虐儿童的父母养育方式探讨   总被引:16,自引:2,他引:16  
目的:探讨受虐儿童的父母养育方式。方法:采用父母养育方式评价量表(EMBU)和一般资料问卷,随机抽取湘潭某工厂子弟中学二年级学生282名完成本次研究。对86名近1年内遭受虐待的儿童(CA)与16名近1年未曾遭受虐待行为儿童(NCA)的父母养育方式进行对照研究。结果:CA与NCA的养育方式中CA组父、母的情感温暖、理解分值低于NCA组;惩罚、严厉、拒绝、否认及过度干涉与保护的分值均高于NCA组,均存在显著性差异。结论:CA与NCA的父母养育方式存在明显不同,增加父母对子女理解及感情交流,减少惩罚、严厉、拒绝、否认会减少儿童虐待的发生。  相似文献   
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