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   34691篇
  免费   3362篇
  国内免费   1404篇
耳鼻咽喉   146篇
儿科学   368篇
妇产科学   333篇
基础医学   3123篇
口腔科学   359篇
临床医学   3726篇
内科学   6315篇
皮肤病学   402篇
神经病学   6394篇
特种医学   1145篇
外国民族医学   10篇
外科学   3085篇
综合类   5489篇
现状与发展   6篇
一般理论   6篇
预防医学   1224篇
眼科学   1263篇
药学   3060篇
  11篇
中国医学   1730篇
肿瘤学   1262篇
  2024年   103篇
  2023年   641篇
  2022年   797篇
  2021年   1219篇
  2020年   1322篇
  2019年   1326篇
  2018年   1241篇
  2017年   1253篇
  2016年   1270篇
  2015年   1309篇
  2014年   2080篇
  2013年   2581篇
  2012年   1890篇
  2011年   2022篇
  2010年   1806篇
  2009年   1752篇
  2008年   1838篇
  2007年   1820篇
  2006年   1718篇
  2005年   1586篇
  2004年   1343篇
  2003年   1217篇
  2002年   1104篇
  2001年   844篇
  2000年   724篇
  1999年   537篇
  1998年   493篇
  1997年   450篇
  1996年   405篇
  1995年   368篇
  1994年   293篇
  1993年   248篇
  1992年   246篇
  1991年   242篇
  1990年   158篇
  1989年   156篇
  1988年   137篇
  1987年   127篇
  1986年   102篇
  1985年   144篇
  1984年   99篇
  1983年   70篇
  1982年   76篇
  1981年   94篇
  1980年   44篇
  1979年   45篇
  1978年   34篇
  1977年   24篇
  1976年   18篇
  1975年   14篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
21.
22.
Objective: Depression afflicts 14% of individuals with type 1 diabetes (T1D). Depression is a robust risk factor for dementia but it is unknown if this holds true for individuals with T1D, who recently started living to an age conferring dementia risk. We examined if depression is a dementia risk factor among elderly individuals with T1D.

Methods: 3,742 individuals with T1D age ≥50 were followed for dementia from 1/1/96-9/30/2015. Depression, dementia, and comorbidities were abstracted from electronic medical records. Cox proportional hazard models estimated the association between depression and dementia adjusting for demographics, glycosylated hemoglobin, severe dysglycemic epidsodes, stroke, heart disease, nephropathy, and end stage renal disease. The cumulative incidence of dementia by depression was estimated conditional on survival dementia-free to age 55.

Results: Five percent (N = 182) were diagnosed with dementia and 20% had baseline depression. Depression was associated with a 72% increase in dementia (fully adjusted HR = 1.72; 95% CI:1.12-2.65). The 25-year cumulative incidence of dementia was more than double for those with versus without depression (27% vs. 12%).

Conclusions: For people with T1D, depression significantly increases dementia risk. Given the pervasiveness of depression in T1D, this has major implications for successful aging in this population recently living to old age.  相似文献   

23.
Abstract

This study was undertaken to compare the concentrations of pro- and anti-angiogenic growth factors, nitric oxide (NO) stable metabolites in maternal serum and embryonic left ventricular (LV) isovolumic relaxation time (IRT, ms) during the first trimester in two groups of women: with pregnancy conceived by assisted reproductive technologies (ART, n?=?39) and normally conceived (control group, n?=?68) pregnancy. The concentration of vasoconstrictor endothelin 1 was 45.5 times more in ART than in control group. On the contrary, the concentrations of NO stable metabolites in ART were 1.9 times less than in control women. The assessment of angiogenic suppressors in ART women demonstrates the decrease in s-endoglin concentration was 1.6 times and in soluble receptor to vascular endothelial growth factor concentration was 2.0 times in comparison with control group. There was a significant increase in LV IRT in ART embryos in comparison to control ones. These data suggest significant changes in pro- anti-angiogenic factors balance and increase in vascular impedance in ART-conceived embryos.  相似文献   
24.
25.
The endocrine system relies on the vasculature for delivery of hormones throughout the body, and the capillary microvasculature is the site where the hormones cross from the blood into the target tissue. Once considered an inert wall, various studies have now highlighted the functions of the capillary endothelium to regulate transport and therefore affect or maintain the interstitial environment. The role of the capillary may be clear in areas where there is a continuous endothelium, yet there also appears to be a role of endothelial cells in tissues with a sinusoidal structure. Here we focused on the most common endocrine disorder, diabetes, and several of the target organs associated with the disease, including skeletal muscle, liver and pancreas. However, it is important to note that the ability of hormones to cross the endothelium to reach their target tissue is a component of all endocrine functions. It is also a consideration in organs throughout the body and may have greater impact for larger hormones with target tissues containing a continuous endothelium. We noted that the blood levels do not always equal interstitial levels, which is what the cells are exposed to, and discussed how this may change in diseases such as obesity and insulin resistance. The capillary endothelium is, therefore, an essential and understudied aspect of endocrinology and metabolism that can be altered in disease, which may be an appropriate target for treatment.  相似文献   
26.
27.
《中国现代医生》2020,58(31):37-39+封三
目的 探讨脂蛋白相关磷脂酶A2(Lp-PLA2)、胰岛素样生长因子-1(IGF-1)与老年血管性痴呆(VD)患者认知功能的关系及预测价值。方法 选择2019 年3~6 月在我院接受治疗的VD 患者60 例为研究对象,同时选取同期在我院接受检查的健康者60 例为对照组,比较两组患者的Lp-PLA2、IGF-1、简易智力状态检查量表评分(MMSE)水平;采用Pearson 相关性分析法对Lp-PLA2、IGF-1 与MMSE 评分的相关性进行分析;采用受试者工作曲线(ROC)下面积(AUC)比较Lp-PLA2、IGF-1 对VD 的预测价值。结果 观察组患者的Lp-PLA2 水平明显高于对照组(P<0.05),观察组患者的IGF-1、MMSE 评分明显低于对照组(P<0.05);Lp-PLA2 与MMSE 评分呈负相关性,IGF-1 与MMSE 评分呈正相关性;Lp-PLA2 与IGF-1 诊断VD 的AUC 值分别为0.940、0.954。结论Lp-PLA2 水平越低,IGF-1 水平越高,患者的认知功能越好,且Lp-PLA2、IGF-1 对老年VD 患者均具有较高的预测价值。  相似文献   
28.
In April, 2019, the Alzheimer's Association Dementia Care Provider Roundtable convened to discuss common challenges faced when implementing person-centered, non-pharmacological practices in long-term care and other settings that provide care and programs for persons living with dementia, and to develop relevant, specific guidance from the perspective of administrative leaders from 23 long-term and community-based care provider organizations (representing home, community-based, and residential care). Guidance related to 5 practice areas emerged from the facilitated discussion: having a foundational person-centered culture, conceptualizing behaviors as expressions and focusing on behavioral support, identifying antecedents and placing person-centeredness before protocols, modifying training to promote person-centered culture, and valuing implementation flexibility. In developing the practice guidance, a related list of priority areas for research and policy were also identified.  相似文献   
29.
In far too many instances treatment of persons with dementia has reflected a fundamental denial of basic human rights. At times, these individuals are treated worse than the treatment of animals when the five basic freedoms of animals, described by Pachana in her editorial, are implemented. A number of such examples of dehumanizing (and “de-animalizing”) persons with dementia are presented. A case is made for the position that this is the direct result of the “medicalization” of dementia and “Alzheimer Disease.” This has led to the disenfranchisement of persons with dementia and their caregivers regarding the treatment of dementia, while medical “expertise” has led to a paradigm of learned helplessness while waiting for “the cure.” While the medicalization of dementia has been a financial success in terms of funding failed researcher to find a cure, it has been a catastrophe for the quality of life of persons with dementia and their caregivers. It is time to take control of the treatment of dementia back, and especially to listen to the voices of persons with dementia. It is time to take action NOW – to become disruptive to the current paradigm. The emperor and his cure have no clothes. We deserve better. We must make this change in paradigm our mission, to demand it, and to accept nothing less. Power to the people.  相似文献   
30.
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