首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2102篇
  免费   184篇
  国内免费   12篇
耳鼻咽喉   4篇
儿科学   31篇
妇产科学   45篇
基础医学   220篇
口腔科学   15篇
临床医学   269篇
内科学   123篇
皮肤病学   11篇
神经病学   938篇
特种医学   16篇
外科学   50篇
综合类   95篇
预防医学   178篇
眼科学   1篇
药学   228篇
  2篇
中国医学   27篇
肿瘤学   45篇
  2024年   5篇
  2023年   37篇
  2022年   57篇
  2021年   78篇
  2020年   68篇
  2019年   75篇
  2018年   99篇
  2017年   81篇
  2016年   85篇
  2015年   96篇
  2014年   128篇
  2013年   235篇
  2012年   105篇
  2011年   104篇
  2010年   93篇
  2009年   103篇
  2008年   100篇
  2007年   114篇
  2006年   96篇
  2005年   78篇
  2004年   66篇
  2003年   72篇
  2002年   69篇
  2001年   31篇
  2000年   38篇
  1999年   21篇
  1998年   30篇
  1997年   23篇
  1996年   10篇
  1995年   13篇
  1994年   8篇
  1993年   12篇
  1992年   6篇
  1991年   9篇
  1990年   8篇
  1989年   4篇
  1988年   5篇
  1987年   3篇
  1986年   8篇
  1985年   8篇
  1984年   4篇
  1983年   1篇
  1982年   1篇
  1981年   1篇
  1979年   4篇
  1978年   1篇
  1975年   2篇
  1974年   2篇
  1972年   1篇
排序方式: 共有2298条查询结果,搜索用时 31 毫秒
941.
942.
Abstract This study examined the relationship between psychological mood, stress and oral hygiene behaviour in a group of 51 regular dental attenders. Subjects brought a saliva sample for cortisol radioimmunoassay. completed the Hospital Anxiety and Depression (HAD) Scale, were assessed for plaque and gingivitis, and were then instructed in toothbrushing. 5 weeks later. 47 subjects were given a full repeat examination. There was a slight reduction in plaque and gingivitis scores, but no change in mood as assessed by HAD Scale and salivary cortisol concentration. Mean anxiety scores were associated with gingivitis level, and mean depression scores with plaque. Neither mood nor cortisol were predictors of subsequent change in plaque or gingivitis.  相似文献   
943.
Research indicates that negative mood effects associated with anabolic-androgenic steroids (referred to as “steroids” here) are likely idiosyncratic, however, little is known about what factors might lead to higher risk for these effects. Research is lacking on the possible contribution of thermogenic/ergogenic drugs to this risk. As thermogenic/ergogenic drugs are stimulants with mood effects similar to those attributed to steroids, this study aimed to build on past research by disentangling the effects on mood from each drug class. An internet survey on current mood as well as steroid and stimulant use was completed by 122 male weightlifters aged 19–57. Current steroid users reported significantly less vigor (ES?=?0.025, p?=?0.021) than steroid abstainers. Current stimulant users reported significantly greater tension/anxiety (ES?=?0.023, p?=?0.019) than stimulant abstainers. Results support the theory that mood effects may be associated with stimulant use. There was no support for any mood effects of steroids. The appearance- and performance-enhancing drug using subsample had slightly less psychological distress on average than normative samples. Stimulant use may be a substantial risk for idiosyncratic negative effects of appearance and performance enhancing drugs on mood.  相似文献   
944.
945.
The use of at least one mood-stabilizing agent is common clinical practice in the treatment of bipolar disorder, regardless of the treatment setting or disease phase. However, a consensus definition of 'mood stabilizer' remains to be established. A mood stabilizer has been operationally described as an agent that is useful in at least one phase of bipolar disorder while not worsening any other phase of the illness. More stringent definitions have been proposed, and it can be argued that a clinically effective mood stabilizer would have efficacy in a broad range of affective, psychotic, behavioral and cognitive domains in all phases of bipolar disorder and would be well tolerated across a range of doses for sustained periods. Clinically effective mood stabilizers should treat mania and depression, while preventing recurrence and improving quality of life. Effective treatment should not precipitate mania, depression, or rapid cycling, and should minimize the burden of treatment-emergent side effects. Data from clinical studies of quetiapine are reviewed in context with the literature discussing traditional and emerging mood stabilizers. Using a liberal definition, the evidence for quetiapine qualifies it as a bimodal mood stabilizer based on its demonstrated effectiveness in the treatment of bipolar mania and depression. Further data suggest that quetiapine has promise across all phases of bipolar disorder with the potential to meet even the most stringent definitions of a mood stabilizer.  相似文献   
946.
RATIONALE: Evidence for the behavioural effects of caffeine is prevalent in the literature. It is associated with increased subjective alertness, improved reaction time and enhanced encoding of new information. However, there is an on-going debate as to whether such changes are in fact improvements or merely a reversal of the negative effects of caffeine withdrawal. Using participants who had consumed their normal daily quota of caffeine this study alleviated this potential confound as all participants were not withdrawn at the time of testing. OBJECTIVES: To determine whether caffeine influenced the mood and performance of non-withdrawn volunteers. METHODS: Sixty eight volunteers, all of whom were regular caffeine consumers, consumed their normal amount of caffeine over the course of the day. Baseline measures of mood and performance were then carried out followed by double-blind administration of caffeine (2 mg/kg) or placebo. The test battery was repeated again 30 min after ingestion of the drink. RESULTS: Our findings showed improvements comparable to previous research. Mood was improved and performance on a number of cognitive measures was improved. The findings are discussed in relation to both noradrenergic and cholinergic neurotransmitter systems. CONCLUSIONS: This study provided evidence against the argument that behavioural changes due to caffeine are merely the reversal of negative withdrawal effects.  相似文献   
947.
动态肺量测定在支气管哮喘中的应用   总被引:1,自引:0,他引:1  
目的探讨动态肺量测定技术在支气管哮喘中的应用.方法建立动态肺量测定技术,对20例支气管哮喘患者每天清晨、下午和入睡前连续14 d动态监测气道功能、症状和情绪.结果白天标准肺功能检查结果正常的支气管哮喘患者,第一秒用力呼气量(FEV1)和最大呼气峰流量(PEF)在夜间和凌晨可出现明显下降.肺功能指标与支气管哮喘症状的相关分析发现,只有7例患者(35%)支气管哮喘症状与FEV1和PEF存在相关关系.4例患者(20%)肺功能基本正常,但有很多症状,症状与FEV1和PEF无相关关系,但与负面情绪相关.另外2例患者(10%)肺功能损害严重,但几乎没有症状.结论动态肺量测定技术能客观反映支气管哮喘患者气道功能的昼夜自然变化,因此可以更准确地反映支气管哮喘的严重程度.动态肺量测定技术结合症状和情绪的同步监测,可以帮助识别出特殊症状感觉类型的支气管哮喘患者.  相似文献   
948.
The pathomechanism of major depressive disorder and the neurobiological basis of antidepressant therapy are still largely unknown. It has been proposed that disturbed hippocampal activity could underlie some of the cognitive and vegetative symptoms of depression, at least in part because of loss of pyramidal cell synaptic contacts, a process that is likely to be reversed by antidepressant treatment. Here we provide evidence that daily administration of the antidepressant fluoxetine to ovariectomized female rats for 5 days induces a robust increase in pyramidal cell dendritic spine synapse density in the hippocampal CA1 field, with similar changes appearing in CA3 after 2 weeks of treatment. This rapid synaptic remodelling might represent an early step in the fluoxetine-induced cascade of responses that spread across the entire hippocampal circuitry, leading to the restoration of normal function in the hippocampus. Hippocampal synaptic remodelling might provide a potential mechanism to explain certain aspects of antidepressant therapy and mood disorders, especially those associated with changes in reproductive state in women, that cannot be reconciled adequately with current theories for depression.  相似文献   
949.
The present study investigated the extent of mood-congruent false and true memory recognition in depression. A group of 25 patients with depression and 28 healthy controls completed a variant of the Deese-Roediger McDermott task. Four lists were read to participants in sequence, followed by a recognition task. The words in each list were associated with a central but unmentioned theme word that was either depression-relevant (i.e., loneliness), delusion-relevant (betrayal), positive (holidays), or neutral (window). Whereas it was expected to replicate the conventional mood-congruent effect in depression (better recognition of depression-relevant items), the available literature did not allow strong predictions to be made on the extent of mood-congruent false recognition in depression. Results showed that depressed patients learned emotionally charged material equally well as healthy participants but forgot significantly more neutral material. A conventional mood-congruent memory bias was not found, but relative to healthy controls, patients with depression committed more false recognition errors for emotionally charged words, particularly for depression-relevant items. The results confirm that depressed patients are biased toward emotional material. Reasons for the absence of the expected mood-congruent memory bias are discussed. It is suggested that researchers as well as clinicians should pay more attention to mood-congruent false recollection, because it may undermine the validity of autobiographic reports in depressive patients and may represent a maintenance factor for the disorder.  相似文献   
950.
In recent years, a number of studies have attempted to characterize psychological disturbances related to various sleep disorders. The objective of this type of research is to investigate the possibility that psychopathology may represent an etiological factor, a complication, and/or a target for treatment. In addition, disordered sleep can present itself in a complex and atypical fashion in which the primary sleep-related component may not be immediately apparent. This article reviews the evidence for a relationship between organic sleep disorders and psychiatric morbidity. Generally, it can be concluded that organic sleep disorders have a profound negative impact on most domains of health-related quality of life. Results for the sleep disorders that have been studied (narcolepsy idiopathic hypersomnia, sleep apnea/hypopnea syndrome, restless legs syndrome, periodic limb movement disorder, and circadian sleep disorders) show strong evidence for an association with mood disorders. After treatment, depression scores may or may not improve to the level of population norms, suggesting that this relationship is more complex than one of mere cause and effect.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号