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   106038篇
  免费   7806篇
  国内免费   2686篇
耳鼻咽喉   1233篇
儿科学   2960篇
妇产科学   1340篇
基础医学   14024篇
口腔科学   1545篇
临床医学   7037篇
内科学   16851篇
皮肤病学   1950篇
神经病学   19202篇
特种医学   2042篇
外国民族医学   14篇
外科学   9231篇
综合类   7788篇
现状与发展   5篇
一般理论   4篇
预防医学   5554篇
眼科学   1668篇
药学   14142篇
  19篇
中国医学   3617篇
肿瘤学   6304篇
  2023年   1991篇
  2022年   3925篇
  2021年   5111篇
  2020年   4296篇
  2019年   5303篇
  2018年   4962篇
  2017年   4316篇
  2016年   3359篇
  2015年   3554篇
  2014年   6738篇
  2013年   8578篇
  2012年   5694篇
  2011年   6195篇
  2010年   4955篇
  2009年   4698篇
  2008年   4573篇
  2007年   3912篇
  2006年   3389篇
  2005年   2790篇
  2004年   2729篇
  2003年   2437篇
  2002年   1835篇
  2001年   1463篇
  2000年   1511篇
  1999年   1251篇
  1998年   1202篇
  1997年   1164篇
  1996年   908篇
  1995年   780篇
  1994年   705篇
  1993年   663篇
  1992年   593篇
  1991年   545篇
  1990年   463篇
  1989年   416篇
  1988年   342篇
  1987年   332篇
  1986年   299篇
  1985年   1053篇
  1984年   1195篇
  1983年   779篇
  1982年   904篇
  1981年   810篇
  1980年   671篇
  1979年   634篇
  1978年   535篇
  1977年   392篇
  1976年   368篇
  1975年   350篇
  1974年   269篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
PurposeAccording to the social determinants of health framework, income inequality is a potential risk factor for adverse mental health. However, few studies have explored the mechanisms suspected to mediate this relationship. The current study addresses this gap through a mediation analysis to determine if social support and community engagement act as mediators linking neighbourhood income inequality to maternal anxiety and depressive symptoms within a cohort of new mothers living in the City of Calgary, Canada.MethodsData collected at three years postpartum from mothers belonging to the All Our Families (AOF) cohort were used in the current study. Maternal data were collected between 2012 and 2015 and linked to neighbourhood socioeconomic data from the 2006 Canadian Census. Income inequality was measured using Gini coefficients derived from 2006 after-tax census data. Generalized structural equation models were used to quantify the associations between income inequality and mental health symptoms, and to assess the potential direct and indirect mediating effects of maternal social support and community engagement.ResultsIncome inequality was not significantly associated with higher depressive symptoms (β = 0.32, 95%CI = −0.067, 0.70), anxiety symptoms (β = 0.11, 95%CI = −0.39, 0.60), or lower social support. Income inequality was not associated with community engagement. For the depression models, higher social support was significantly associated with lower depressive symptoms (β = −0.13, 95%CI = −0.15, −0.097), while community engagement was not significantly associated with depressive symptoms (β = 0.059, 95%CI = −0.15, 0.27). Similarly, for the anxiety models, lower anxiety symptoms were significantly associated with higher levels of social support (β = −0.17, 95%CI = −0.20, −0.13) but not with higher levels of community engagement (β = 0.14, 95%CI = −0.14, 0.41).ConclusionThe current study did not find clear evidence for social support or community engagement mediating the relationship between neighbourhood income inequality and maternal mental health. Future investigations should employ a broader longitudinal approach to capture changes in income inequality, potential mediators, and mental health symptomatology over time.  相似文献   
3.
4.
《Clinical neurophysiology》2021,132(10):2357-2364
ObjectivesTo investigate the subcortical somatosensory evoked potentials (SEPs) to electrical stimulation of either muscle or cutaneous afferents.MethodsSEPs were recorded in 6 patients suffering from Parkinson’s disease (PD) who underwent electrode implantation in the pedunculopontine (PPTg) nucleus area. We compared SEPs recorded from the scalp and from the intracranial electrode contacts to electrical stimuli applied to: 1) median nerve at the wrist, 2) abductor pollicis brevis motor point, and 3) distal phalanx of the thumb. Also the high-frequency oscillations (HFOs) were analysed.ResultsAfter median nerve and pure cutaneous (distant phalanx of the thumb) stimulation, a P1-N1 complex was recorded by the intracranial lead, while the scalp electrodes recorded the short-latency far-field responses (P14 and N18). On the contrary, motor point stimulation did not evoke any low-frequency component in the PPTg traces, nor the N18 potential on the scalp. HFOs were recorded to stimulation of all modalities by the PPTg electrode contacts.ConclusionsStimulus processing within the cuneate nucleus depends on modality, since only the cutaneous input activates the complex intranuclear network possibly generating the scalp N18 potential.SignificanceOur results shed light on the subcortical processing of the somatosensory input of different modalities.  相似文献   
5.
6.
AimThe aim of the study was to describe the characteristics of the Bachelor’s thesis of fourth-year nursing students at a Spanish public university, the criteria that students used to choose a topic and students’ degree of satisfaction after completing the Bachelor’s thesis.DesignQuantitative study.MethodsWe examined 420 Bachelor’s theses carried out from 2013 to 2018 and conducted an online survey among fourth-year students in the 2017–18 and 2018–19 academic years (81 completed questionnaires).ResultsThe Bachelor’s thesis took the form of a research proposal. The most frequent proposal type was a qualitative hospital-based study whose objective was to understand the experiences of adult or adolescent patients, close family members, or nurses. Students chose topics for personal reasons. Most participants reported feeling satisfied with the knowledge and skills acquired.ConclusionsStudents completing a Bachelor’s thesis in the form of a research proposal have the potential to transfer their research skills to their nursing practice.  相似文献   
7.
8.
9.
Inflammatory bowel disease (IBD) is a chronic disease that requires chronic treatment throughout the evolution of the disease, with a complex physiopathology that entails great challenges for the development of new and specific treatments for ulcerative colitis and Crohn´s disease. The anti-tumor necrosis factor alpha therapy has impacted the clinical course of IBD in those patients who do not respond to conventional treatment, so there is a need to develop new therapies and markers of treatment response. Various pathways involved in the development of the disease are known and the new therapies have focused on blocking the inflammatory process at the gastrointestinal level by oral, intravenous, subcutaneous, and topical route. All these new therapies can lead to more personalized treatments with higher success rates and fewer relapses. These treatments have not only focused on clinical remission, but also on achieving macroscopic changes at the endoscopic level and microscopic changes by achieving mucosal healing. These treatments are mainly based on modifying signaling pathways, by blocking receptors or ligands, reducing cell migration and maintaining the integrity of the epithelial barrier. Therefore, this review presents the efficacy and safety of the new treatments that are currently under study and the advances that have been made in this area in recent years.  相似文献   
10.
《Molecular therapy》2022,30(8):2856-2867
  1. Download : Download high-res image (173KB)
  2. Download : Download full-size image
  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