全文获取类型
收费全文 | 26647篇 |
免费 | 2604篇 |
国内免费 | 425篇 |
专业分类
耳鼻咽喉 | 78篇 |
儿科学 | 518篇 |
妇产科学 | 508篇 |
基础医学 | 2403篇 |
口腔科学 | 125篇 |
临床医学 | 3893篇 |
内科学 | 1964篇 |
皮肤病学 | 122篇 |
神经病学 | 8874篇 |
特种医学 | 212篇 |
外科学 | 1004篇 |
综合类 | 3225篇 |
现状与发展 | 2篇 |
一般理论 | 4篇 |
预防医学 | 1775篇 |
眼科学 | 92篇 |
药学 | 2441篇 |
34篇 | |
中国医学 | 1725篇 |
肿瘤学 | 677篇 |
出版年
2024年 | 84篇 |
2023年 | 517篇 |
2022年 | 514篇 |
2021年 | 1140篇 |
2020年 | 1175篇 |
2019年 | 1087篇 |
2018年 | 1040篇 |
2017年 | 1160篇 |
2016年 | 1193篇 |
2015年 | 1078篇 |
2014年 | 1743篇 |
2013年 | 2463篇 |
2012年 | 1586篇 |
2011年 | 1587篇 |
2010年 | 1418篇 |
2009年 | 1313篇 |
2008年 | 1279篇 |
2007年 | 1302篇 |
2006年 | 1119篇 |
2005年 | 939篇 |
2004年 | 755篇 |
2003年 | 706篇 |
2002年 | 605篇 |
2001年 | 478篇 |
2000年 | 339篇 |
1999年 | 245篇 |
1998年 | 268篇 |
1997年 | 285篇 |
1996年 | 202篇 |
1995年 | 187篇 |
1994年 | 201篇 |
1993年 | 144篇 |
1992年 | 162篇 |
1991年 | 140篇 |
1990年 | 121篇 |
1989年 | 133篇 |
1988年 | 121篇 |
1987年 | 133篇 |
1986年 | 99篇 |
1985年 | 126篇 |
1984年 | 93篇 |
1983年 | 64篇 |
1982年 | 69篇 |
1981年 | 58篇 |
1980年 | 48篇 |
1979年 | 37篇 |
1978年 | 23篇 |
1977年 | 29篇 |
1976年 | 20篇 |
1975年 | 15篇 |
排序方式: 共有10000条查询结果,搜索用时 171 毫秒
71.
目的在磁共振液体衰减翻转恢复(FLAIR)序列图像,胼胝体压部出现高信号通常被认为是病理变化。本研究的目的是分析这种病理改变在老年患者中的发生率及其可能的病理机制,并综述该MR表现的鉴别诊断。方法回顾性复习132例疑诊神经系统疾病的患者(男56例,女76例,年龄9~90岁,平均59岁)的FLAIR序列图像。分别观察胼胝体压部、深部脑白质改变、梗死及脑萎缩的情况。结果在132例患者中,33例(平均年龄59岁)患者的FLAIR像上胼胝体压部可见异常高信号改变,这种异常改变与年龄、脑白质的异常、脑萎缩及认知障碍的表现显著相关。结论FLAIR像上胼胝体压部高信号在老年患者中是常见的表现,多见于有认知障碍的老年患者。其病理变化通常被称之为“脑白质疏松症”。了解该异常表现发生的机制及该表现的鉴别诊断可避免不必要的有创诊断和治疗。 相似文献
72.
Katherine Patterson Corinna Young Steven Paul Woods Ofilio Vigil Igor Grant J. Hampton Atkinson 《International journal of methods in psychiatric research》2006,15(2):75-82
Major Depressive Disorder (MDD) is among the most prevalent but underdiagnosed psychiatric disorders in persons with HIV infection. Given the known adverse impact of comorbid MDD on HIV disease progression and health‐related quality of life, it is important both for research and for efficient, effective clinical care, to validate existing screening measures that may discriminate between MDD and the somatic symptoms of HIV (such as fatigue). In the current study, we evaluated the concurrent predictive validity of the Profile of Mood States (POMS) Depression‐Dejection scale in detecting current MDD in 310 persons with HIV infection. The Structured Clinical Interview for DSM‐IV (SCID) diagnosis of MDD and the Cognitive‐Affective scale from the Beck Depression Inventory (BDI‐CA) served as comparative diagnostic and severity measures of depression, respectively. Results demonstrated that the POMS Depression‐Dejection scale accurately classified persons with and without MDD SCID diagnoses, with an overall hit rate of 80%, sensitivity of 55%, specificity of 84%, and negative predictive power of 91% using a recommended cutpoint of 1.5 standard deviations above the normative mean. Moreover, the POMS performed comparably to the BDI‐CA in classifying MDD. Findings support the predictive validity of the POMS Depression‐Dejection scale as a screening instrument for MDD in persons with HIV disease. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
73.
冯辉 《天津中医药大学学报》2006,23(5):371-371
抑郁症的发病率呈上升趋势,引起全社会的重视。中医药治疗该病具有独到的优势,认为病位在脑,病机为气痰郁结、阴血不足、精髓不足、阴虚内热,据此提出抑郁症分为3期,初期为肝郁,中期为心脾两虚,后期为肾虚。 相似文献
74.
A neurotrophic model for stress-related mood disorders. 总被引:31,自引:0,他引:31
There is a growing body of evidence demonstrating that stress decreases the expression of brain-derived neurotrophic factor (BDNF) in limbic structures that control mood and that antidepressant treatment reverses or blocks the effects of stress. Decreased levels of BDNF, as well as other neurotrophic factors, could contribute to the atrophy of certain limbic structures, including the hippocampus and prefrontal cortex that has been observed in depressed subjects. Conversely, the neurotrophic actions of antidepressants could reverse neuronal atrophy and cell loss and thereby contribute to the therapeutic actions of these treatments. This review provides a critical examination of the neurotrophic hypothesis of depression that has evolved from this work, including analysis of preclinical cellular (adult neurogenesis) and behavioral models of depression and antidepressant actions, as well as clinical neuroimaging and postmortem studies. Although there are some limitations, the results of these studies are consistent with the hypothesis that decreased expression of BDNF and possibly other growth factors contributes to depression and that upregulation of BDNF plays a role in the actions of antidepressant treatment. 相似文献
75.
目的 了解蚌埠医学院在校学生心理状况 ,为素质教育提供服务。方法 采用症状自评量表 (SCL- 90 )对该校 1~ 4年级学生进行调查分析。结果 该校在校生有 5个因子得分高于全国大学生常模 ,高年级学生得分高于低年级 ,男女生在人际、抑郁、敌对、偏执等方面差异有显著性。结论 应针对大学生的心理特点 ,在大学院校进行心理健康教育。 相似文献
76.
老年期痴呆抑郁和焦虑障碍共病研究 总被引:3,自引:0,他引:3
目的:了解老年期痴呆患者抑郁和焦虑障碍共病率及其相关因素。方法:将100例老年期痴呆患者分为两组,阿尔茨海默病(AD)组和血管性痴呆(VD)组。用简明精神病评定量表(BPRS)、Hamilton抑郁量表(HAMD)、Hamilton焦虑量表(HAMA)进行评定。结果:AD组有焦虑20例,伴抑郁17例;VD组有焦虑17例,伴抑郁15例。共病28例,AD组与VD组各14例。AD组与VD组在HAMD因子分有明显差异(P〈0.05)。结论:老年期痴呆患者抑郁和焦虑共病率较高,应引起高度重视。 相似文献
77.
目的 探讨改良电针痉挛连续两次发作治疗重性抑郁症的疗效。方法 使用YA型电针痉挛治疗仪 ,对 64例重性抑郁症患者进行连续两次发作 (试验组 )和单次发作 (对照组 )治疗 ,采用HAMD抑郁量表评分。结果 试验组临床显效率为 82 3 % ,对照组为 60 0 % ,试验组的疗效显著性地优于对照组 (χ2 =3 94,P <0 0 5 )。HAMD抑郁量表评定 :两组治疗前后总分均值比较均有显著差异 (P <0 0 1) ,试验组和对照组治疗后总分均值有显著差异 (t=5 .10 8,P <0 0 1) ;两组 4次发作治疗后总分均值比较试验组显效快于对照组 ;试验组的绝望感、认知障碍、迟滞因子分均值减低比对照组更明显 (P <0 0 1)。结论 改良电针痉挛连续两次发作疗法见效快、疗效好 ,无明显副作用 ,是治疗重性抑郁症的一种新方法 相似文献
78.
Dysphoric Rumination Impairs Concentration on Academic Tasks 总被引:3,自引:0,他引:3
Three studies investigated the effects of dysphoric rumination on concentration during 3 academic tasks—reading a passage from the GRE (Study 1), watching a videotaped lecture (Study 2), and proofreading written text (Study 3). Before performing these tasks, dysphoric and nondysphoric students were induced either to ruminate about themselves or to distract themselves by focusing on neutral images (all three studies) or by planning an event (Study 1). The results supported our hypothesis that dysphoric rumination, relative to distraction, would impair students' concentration. In all 3 studies, dysphoric ruminators reported difficulty concentrating, as well as interfering thoughts, during the relevant academic tasks. Furthermore, dysphoric ruminators were slower than dysphoric distractors in completing the tasks—specifically, reading the GRE passage (Study 1) and answering lecture comprehension questions (Study 2). In addition, dysphoric participants who ruminated showed impaired reading strategies (Study 1), reduced comprehension of academic material (Study 2), and poor proofreading performance (Study 3). These findings suggest that, in addition to its documented adverse effects on mood, thinking, and problem-solving, self-focused rumination interferes with instrumental behavior. Implications for social relationships and job performance are discussed. 相似文献
79.
Joan Prudic Mark Olfson Steven C Marcus Rice B Fuller Harold A Sackeim 《Neuropsychopharmacology》2004,55(3):301-312
BACKGROUND: Clinical trials indicate that electroconvulsive therapy (ECT) is the most effective treatment for major depression, but its effectiveness in community settings has not been examined. METHODS: In a prospective, naturalistic study involving 347 patients at seven hospitals, clinical outcomes immediately after ECT and over a 24-week follow-up period were examined in relation to patient characteristics and treatment variables. RESULTS: The sites differed markedly in patient features and ECT administration but did not differ in clinical outcomes. In contrast to the 70%-90% remission rates expected with ECT, remission rates, depending on criteria, were 30.3%-46.7%. Longer episode duration, comorbid personality disorder, and schizoaffective disorder were associated with poorer outcome. Among remitters, the relapse rate during follow-up was 64.3%. Relapse was more frequent in patients with psychotic depression or comorbid Axis I or Axis II disorders. Only 23.4% of ECT nonremitters had sustained remission during follow-up. CONCLUSIONS: The remission rate with ECT in community settings is substantially less than that in clinical trials. Providers frequently end the ECT course with the view that patients have benefited fully, yet formal assessment shows significant residual symptoms. Patients who do not remit with ECT have a poor prognosis; this underscores the need to achieve maximal improvement with this modality. 相似文献
80.
Antidepressant-associated maniform states in acute treatment of patients with bipolar-I depression 总被引:2,自引:0,他引:2
R. Bottlender Daniel Rudolf Anton Strauss Hans-Jürgen Möller 《European archives of psychiatry and clinical neuroscience》1998,248(6):296-300
Medical records of 158 patients with bipolar depression were analysed for the incidence of a switch from depression to maniform
states (mania and hypomania). Relation to psychopharmacological treatment was investigated. Thirty-nine (25%) patients of
the total sample had switched to a maniform state during the treatment period in the hospital. Among that group the phenomenon
occurred in 23 patients (15%) as a hypomania and in 16 patients (10%) as a mania. Patients with a switch were significantly
more often treated with tricyclic antidepressants (TCA) than patients without switch (79.5% vs 51.3%). Mood stabilising medication
might reduce the risk for switching, especially in patients treated with TCA; however, it seems not totally sufficient, since
59% of the switched patients received mood stabilisers. The switch phenomenon was not associated with sociodemographic or
clinical data.
Received: 23 September 1998 / Accepted: 28 September 1998 相似文献