全文获取类型
收费全文 | 16208篇 |
免费 | 756篇 |
国内免费 | 118篇 |
专业分类
耳鼻咽喉 | 59篇 |
儿科学 | 200篇 |
妇产科学 | 240篇 |
基础医学 | 1817篇 |
口腔科学 | 37篇 |
临床医学 | 2011篇 |
内科学 | 1190篇 |
皮肤病学 | 79篇 |
神经病学 | 4941篇 |
特种医学 | 86篇 |
外科学 | 380篇 |
综合类 | 2170篇 |
预防医学 | 1372篇 |
眼科学 | 23篇 |
药学 | 1580篇 |
4篇 | |
中国医学 | 762篇 |
肿瘤学 | 131篇 |
出版年
2024年 | 31篇 |
2023年 | 207篇 |
2022年 | 479篇 |
2021年 | 647篇 |
2020年 | 609篇 |
2019年 | 457篇 |
2018年 | 485篇 |
2017年 | 574篇 |
2016年 | 567篇 |
2015年 | 567篇 |
2014年 | 1368篇 |
2013年 | 1408篇 |
2012年 | 1093篇 |
2011年 | 1453篇 |
2010年 | 974篇 |
2009年 | 966篇 |
2008年 | 924篇 |
2007年 | 809篇 |
2006年 | 619篇 |
2005年 | 483篇 |
2004年 | 410篇 |
2003年 | 353篇 |
2002年 | 266篇 |
2001年 | 175篇 |
2000年 | 138篇 |
1999年 | 104篇 |
1998年 | 85篇 |
1997年 | 91篇 |
1996年 | 52篇 |
1995年 | 57篇 |
1994年 | 46篇 |
1993年 | 39篇 |
1992年 | 29篇 |
1991年 | 29篇 |
1990年 | 29篇 |
1989年 | 19篇 |
1988年 | 34篇 |
1987年 | 26篇 |
1986年 | 21篇 |
1985年 | 71篇 |
1984年 | 51篇 |
1983年 | 25篇 |
1982年 | 30篇 |
1981年 | 28篇 |
1980年 | 16篇 |
1979年 | 27篇 |
1978年 | 21篇 |
1977年 | 14篇 |
1975年 | 12篇 |
1974年 | 19篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
Maurizio Severino Anja F. Pedersen Viktorija Trajkovska Ellen Christensen Rasmus Lohals Lone M. Veng Gitte M. Knudsen Susana Aznar 《Neuroscience letters》2007
Although loss of cholinergic neurons in the basal forebrain is considered a key initial feature in Alzheimer's disease (AD), changes in other transmitter systems, including serotonin and 5-HT2A receptors, are also associated with early AD. The aim of this study was to investigate whether elimination of the cholinergic neurons in the basal forebrain directly affects 5-HT2A receptor levels. For this purpose intraventricular injection of the selective immunotoxin 192 IgG-Saporin was given to rats in doses of either 2.5 or 5 μg. The rats were sacrificed after 1, 2, 4 and 20 weeks. 5-HT2A protein levels were determined by western techniques in frontal cortex and hippocampus. A significant 70% downregulation in frontal cortex and a 100% upregulation in hippocampus of 5-HT2A receptor levels were observed 20 weeks after the cholinergic lesion when using the highest dose of 192 IgG-Saporin. Our results show that cholinergic deafferentation leads to decreased frontal cortex and increased hippocampal 5-HT2A receptor levels. This is probably a consequence of the interaction between the serotonergic and the cholinergic system that may vary depending on the brain region. 相似文献
112.
老年腔隙性脑梗死患者抑郁情绪及影响因素的研究 总被引:4,自引:1,他引:4
脑梗死后抑郁状态是脑卒中常见的并发症之一 ,其发生率为 2 3%~ 6 5 % [1] 。脑梗死后抑郁不仅严重影响患者的生活质量 ,而且可直接影响其康复和预后。随着医学影像学的发展 ,腔隙性脑梗死(Lacunarcerebralinfarction ,LI)的诊断率逐渐增高。为探讨老年LI患者抑郁的临床特点 ,我们收集老年LI病人 12 6例 ,对其抑郁的特点、抑郁症状与LI的关系及影响因素进行了研究 ,现报告如下。1 资料与方法1.1 研究对象为 1998年 1月至 2 0 0 0年 12月在本院及济宁市一院精神科住院的LI病人 12 6例 ,年龄 6 0~ 82… 相似文献
113.
大学生群体中社会支持、自我效能感在应激与抑郁间的作用 总被引:7,自引:5,他引:7
目的:探讨社会支持、自我效能感在应激/抑郁间的作用机制。方法:对370名大学生施测流调中心用抑郁量表(CED-S)、青少年生活事件量表(ASLEC)、社会支持评定量表(SSRS)、一般自我效能感量表(GSES)。采用层次回归分析和复回归分析验证社会支持、自我效能感在应激/抑郁间的作用。结果:社会支持×应激显著预测了抑郁的变化;自我效能感中介了应激与抑郁的关系。结论:社会支持、自我效能感在应激/抑郁间的作用机制是不同的,社会支持是调节变量,自我效能感是中介变量。 相似文献
114.
Lack of functional estrogen receptor beta influences anxiety behavior and serotonin content in female mice 总被引:5,自引:0,他引:5
Estrogen has been linked to the modulation of anxiety in females. Here we report results of anxiety tests conducted in female estrogen receptor beta (ERbeta) knockout (ERbetaKO) and wild-type (WT) mice. Ovariectomized (OVX) mice treated with chronic estradiol (E2) replacement did not behave differently on the elevated plus-maze when compared with OVX mice that did not experience hormone replacement. However, a genotype difference was noted; WT females were more likely to explore the distal portion of the open arm of the maze than ERbetaKO littermates. In addition, ERbetaKO female mice had significantly lower serotonin (5-HT) content than WT littermates in several brain regions including: the bed nucleus of the stria terminalis, preoptic area, and hippocampus. A similar trend was noted in the dorsal raphe nucleus. Dopamine content was reduced within the caudate putamen in ERbetaKO mice as compared to brains from WT animals. Thus, in the absence of functional ERbeta, regardless of the presence or absence of circulating E2 in plasma, female mice exhibited enhanced anxiety and decreased concentrations of 5-HT or dopamine in several brain regions. We hypothesize that ERbeta is required during development to modulate the effects of estrogen on anxiety and catecholamine concentrations in female mouse brains. 相似文献
115.
Phenomenology and family history in DSM-III psychotic depression 总被引:1,自引:0,他引:1
Depressed inpatients with psychotic features were compared to those without them in terms of demographic features, depressive symptoms at intake and family history. These variables were then used to compare patients with mood-congruent psychotic features to those with mood-incongruent psychotic features. Patterns of familial psychopathology were similar for psychotic and non-psychotic patients. In accord with other studies, the families of mood-incongruent patients had slightly more schizophrenia and significantly less depression than did the families of mood-congruent patients. Depressive symptoms, particularly those used to define major depression and melancholia, were more severe in psychotic patients. Moreover, these particular depressive symptoms were more likely to distinguish mood-congruent from mood-incongruent patients than were other depressive symptoms. Thus mood-congruent psychotic features accompanied a more typical depressive syndrome than did mood-incongruent psychotic features. 相似文献
116.
Neurovegetative symptoms in chronic pain and depression 总被引:1,自引:0,他引:1
The pattern and frequency of neurovegetative symptoms was studied in 57 patients with chronic pain. Seventy-nine percent of these patients had a diagnosable depressive illness, but endogenous depression was rare (5%). Patients with chronic pain were divided into major depressives, minor/intermittent depressives and patients with no depression. A control group of nonendogenous major depressives without pain was also utilized. Major depressives differed from the other two chronic pain groups in that there was more frequent or severe early waking, weight loss, anorexia, diminished libido and initial insomnia. Diurnal variation of mood was not a characteristic of major depression with chronic pain, and did not differ in frequency from the other two chronic pain groups. Major depressives exhibited a profile of neurovegetative symptoms very similar to that found in the control group of major depressives. Over one-third of minor/intermittent depressed patients with chronic pain exhibited atypical (reversed) vegetative symptoms of hyperphagia and weight gain. This finding, together with our review of the literature, suggests an important and previously unrecognized link between atypical depression and chronic pain. 相似文献
117.
Csaba M. Banki Maria Vojnik Mihaly Arato Zsuzsa Papp Zsuzsa Kovacs 《European archives of psychiatry and clinical neuroscience》1985,235(1):32-37
Summary Baseline and TRH-induced changes of thyroid stimulating hormone (TSH), prolactin (PRL), and growth hormone (GH) were measured in 15 healthy control subjects and 63 psychiatric inpatients with DSM-III diagnoses of major depression (n = 19), schizophrenic disorder (n = 20), alcohol dependence (n = 10), and adjustment disorder (n = 14); baseline and postdexamethasone cortisol (CS) were also determined 3–6 days after the TRH-challenge. All patients and controls were women of similar mean age, weight, height, and they were free from interfering illness or drugs.Baseline TSH and PRL were lower in depression, TRH-induced TSH and PRL responses were lower in the whole patient group, but most markedly in depression and alcohol dependence. Postdexamethasone CS was significantly higher in depression, schizophrenia and alcohol dependence. Basal GH did not differentiate the subgroups; TRH-induced pathological GH responses were sometimes found in the patient groups. The differences were most marked quantitatively in major depression: a multivariate analysis of variance showed that TSH, postdexamethasone CS and PRL were the most important variables in separating patients from controls. A discriminant function derived from these variables classified all controls and 18 of 19 depressed patients correctly; however, 25 of the 44 other patients were also classified with depression.It was confirmed that psychiatric patients show significantly more endocrine disturbances than controls, and this was seen not only in major depression but also in at least three other conditions. Further work is needed to identify other neuroendocrine patterns more specific to depressive disorder. 相似文献
118.
目的 比较分析我国中年和老年女性抑郁倾向及影响因素的差异性,为有针对性的改善中年与老年女性群体的心理健康水平提供参考。方法 选取中国健康与养老追踪调查(CHARLS)2018年数据,以45~59岁中年女性和≥60岁老年女性为研究对象,采用流行病调查中心抑郁量表(CES-D)评估其抑郁倾向。中年和老年女性抑郁倾向的比较采用均值检验,使用倾向性评分匹配法(PSM)对中年和老年女性进行匹配后,进一步探索其组间的差异,采用稳健Tobit回归模型探究抑郁倾向的影响因素。结果 7 964例中老年女性的CES-D评分为(9.53±6.86)分。其中,中年女性、老年女性CES-D评分分别为(9.13±6.62)分、(9.96±7.09)分,老年女性的抑郁倾向评分高于中年女性(t=-5.361,P<0.001)。稳健Tobit回归结果显示,文化程度、居住地、健康自评、身体残疾、慢性病、因身体疼痛而苦恼、BADL受损、IADL受损、是否与配偶或同居者一起生活、家庭成员数量、现有负债、地带分布是中年和老年女性抑郁倾向共同的影响因素。年龄及其二次项、子女数量、有无农业自雇以外的工作是中年女性抑郁倾向的影响因素; 每月来看望1次及以上的子女数量、是否照顾孙子女、是否有社交活动、是否上网、是否退休是老年女性抑郁倾向的影响因素。结论 我国老年女性的抑郁倾向较中年女性明显,且影响因素存在差异性。应针对不同人群特征,提供更有针对性的预防策略,促进中年和老年女性心理健康良性发展。 相似文献
119.
目的 分析医学院校大学生宿舍人际关系对其抑郁情绪的影响,为促进大学生身心健康发展提供依据。方法 采用分层随机抽样法,抽取西南地区某医科大学的1215名在校大学生,采用流调用抑郁自评量表(CES-D)和感知亲密关系质量量表(PRQC)修改版进行问卷调查。采用t检验、方差分析和多元线性回归进行统计分析。结果 大学生CES-D量表平均得分14.25±9.11分,抑郁情绪检出率为24.5%,其中轻、中、重抑郁情绪检出率分别为18.3%、5.4%、0.8%。有抑郁情绪的大学生宿舍人际关系总得分及各维度得分均低于无抑郁情绪者(t=14.471,P<0.05),多元线性回归分析显示年级、家庭所在地、宿舍亲密度、宿舍信任度、宿舍氛围影响大学生抑郁情绪(P<0.05)。结论 宿舍人际关系对大学生抑郁情绪有影响,高校工作者应重视早期识别抑郁情绪的学生,关注学生的宿舍人际关系状况,提高大学生的心理健康水平。 相似文献
120.
目的了解宁夏川区和山区妇女抑郁情绪现状及影响因素的差异,为制定基于地区的妇女抑郁防控措施提供依据。方法2020年7—8月以方便抽样法选取调查对象,采用自制一般人口学问卷、患者健康问卷(PHQ-9)及精神卫生与心理保健知识问卷对1816名妇女进行面对面问卷调查。结果川区和山区妇女抑郁总分分别为(5.04±3.55)分和(4.20±3.49)分,情感维度得分分别为(3.11±2.33)分和(2.69±2.28)分,身体症状维度得分分别为(1.93±1.60)分和(1.51±1.49)分,差异均有统计学意义(t=4.892,3.766,5.510,均P<0.05)。多元线性回归分析结果显示:影响川区妇女抑郁得分的因素包括年龄、文化程度、家庭年收入、精神卫生与心理保健知识水平(均P<0.05);影响山区妇女抑郁得分的因素包括户籍、年龄、职业及家庭常住人口数(均P<0.05)。结论宁夏川区妇女抑郁情绪比山区妇女更突出,川区和山区妇女抑郁情绪的影响因素有一定差异。今后应基于川区和山区社会环境的差异评估妇女抑郁情绪的流行状况,开展监测与差异化干预。 相似文献