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   34971篇
  免费   4260篇
  国内免费   802篇
耳鼻咽喉   266篇
儿科学   779篇
妇产科学   394篇
基础医学   2705篇
口腔科学   893篇
临床医学   5839篇
内科学   4332篇
皮肤病学   335篇
神经病学   3690篇
特种医学   814篇
外科学   3004篇
综合类   3456篇
现状与发展   4篇
一般理论   6篇
预防医学   6698篇
眼科学   257篇
药学   3523篇
  80篇
中国医学   1758篇
肿瘤学   1200篇
  2024年   203篇
  2023年   1149篇
  2022年   1915篇
  2021年   2625篇
  2020年   2345篇
  2019年   2051篇
  2018年   1799篇
  2017年   1672篇
  2016年   1568篇
  2015年   1461篇
  2014年   2512篇
  2013年   3202篇
  2012年   1812篇
  2011年   1999篇
  2010年   1530篇
  2009年   1454篇
  2008年   1560篇
  2007年   1440篇
  2006年   1136篇
  2005年   1038篇
  2004年   826篇
  2003年   710篇
  2002年   564篇
  2001年   513篇
  2000年   426篇
  1999年   363篇
  1998年   323篇
  1997年   288篇
  1996年   256篇
  1995年   219篇
  1994年   206篇
  1993年   140篇
  1992年   129篇
  1991年   101篇
  1990年   78篇
  1989年   69篇
  1988年   49篇
  1987年   45篇
  1986年   48篇
  1985年   51篇
  1984年   36篇
  1983年   19篇
  1982年   25篇
  1981年   19篇
  1980年   16篇
  1979年   11篇
  1978年   8篇
  1977年   5篇
  1975年   7篇
  1974年   4篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
ObjectivesTo confirm what impairments are present in runners with Achilles tendinopathy (AT) and explore the variance of AT severity in an adequately powered study.DesignCase-control study.SettingTwo private physiotherapy clinics in Australia and Spain.ParticipantsForty-four recreational male runners with AT and 44 healthy controls matched by age, height, and weight.Main outcome measuresDemographics, activity (IPAQ-SF), pain and function (VISA-A), pain during hopping (Hop pain VAS), hopping duration, psychological factors (TSK-11, PASS20), and physical tests regarding lower-limb maximal strength and endurance.ResultsBody mass index (BMI), activity, VISA-A, pain, and duration of hopping, TSK-11, PASS20, standing heel raise to failure, seated heel raise and leg extension 6RM, hip extension and abduction isometric torque were significantly different between groups (P < 0.05) with varied effect sizes (V = 0.22, d range = 0.05–4.18). 46% of AT severity variance was explained by higher BMI (β = −0.41; p = 0.001), weaker leg curl 6RM (β = 0.32; p = 0.009), and higher pain during hopping (β = −0.43; p = 0.001).ConclusionRunners with AT had lower activity levels, lower soleus strength, and were less tall. BMI, pain during hopping, and leg curl strength explained condition severity. This information, identified with clinically applicable tools, may guide clinical assessment, and inform intervention development.  相似文献   
3.
4.
目的 运用网络药理学方法及分子对接技术探讨黄芪干预腹膜纤维化的可能机制。方法 利用中药系统药理学数据库及分析平台(TCMSP)检索黄芪的主要化学成分及靶点,并补充文献报道相关药理作用的成分作为潜在活性成分。以"peritoneal fibrosis"为关键词分别在OMIM、Genecards获取目前已知的与腹膜纤维化相关的疾病靶点,后取两者的交集靶点;对交集基因通过STRING数据库与Cytoscape 3.7.2软件构建"药物-成分-靶点-疾病"网络及蛋白互作(PPI)网络并筛选核心网络。基于R软件使用Bioconductor生物信息软件对核心靶点进行GO及KEGG富集分析,最终采用AutoDock软件将主要有效成分与核心靶点进行分子对接,得出其结合能力。结果 筛选出20个黄芪活性成分及文献报道有相关药理作用4个, 457药物作用靶点,与674个腹膜纤维化病靶点取交集,得到86个共同靶点。GO功能富集分析提示黄芪拮抗腹膜纤维化主要参与了蛋白激酶B信号转导的调节、细胞对化学的应激反应、炎症反应的调节等通路; KEGG通路富集分析主要涉及调控肿瘤、磷脂酰肌醇-3-羟激酶-蛋白激酶B(PI3K-Akt)、晚期糖基化终末产物/晚期糖基化终末产物受体(AGE-RAGE)、人类巨细胞病毒感染、HIF-1信号通路等;分子对接结果显示关键靶点与活性成分具有较好的结合能力。结论 黄芪治疗腹膜纤维化的分子机制,可能与抑制炎症及氧化应激反应、调节多种信号通路等相关。  相似文献   
5.
6.
The current study explored the influence of three methods of parental emotion discourse (structured story-telling, reminiscing, and picture book) and their relation to preschoolers’ emotion understanding. Thirty-seven families participated in the study. Analyses showed that the structured story-telling method produced more emotion words, was high in unique emotion words, and was high for both emotion labelling and explanations. All three methods showed some potential to predict preschooler’s emotion understanding. Structured story-telling was best at predicting role-taking, while reminiscing and the picture book both were better at predicting situation knowledge. Additional studies are needed to further explore the influence of different methods of assessing emotion discourse to enhance validity and reliability of research in this field.  相似文献   
7.
It is well recognized that the world population is ageing rapidly. Therefore, it is important to understand ageing processes at the cellular and molecular levels to predict the onset of age‐related diseases and prevent them. Recent research has focused on the identification of ageing biomarkers, including those associated with the properties of the Golgi apparatus. In this context, Golgi‐mediated glycosylation of proteins has been well characterized. Additionally, other studies show that the secretion of many compounds, including pro‐inflammatory cytokines and extracellular matrix–degrading enzymes, is modified during ageing, resulting in physical and functional skin degradation. Since the Golgi apparatus is a central organelle of the secretory pathway, we investigated its structural organization in senescent primary human dermal fibroblasts using confocal and electron microscopy. In addition, we monitored the expression of Golgi‐related genes in the same cells. Our data showed a marked alteration in the Golgi morphology during replicative senescence. In contrast to its small and compact structure in non‐senescent cells, the Golgi apparatus exhibited a large and expanded morphology in senescent fibroblasts. Our data also demonstrated that the expression of many genes related to Golgi structural integrity and function was significantly modified in senescent cells, suggesting a relationship between Golgi apparatus function and ageing.  相似文献   
8.
ABSTRACT

Introduction

Individuals with autism spectrum disorder (ASD) and intellectual disability (ID) seem to be at increased risk for post-traumatic stress disorder (PTSD), but knowledge is sparse regarding its identification in this population. Previous research indicates that certain symptoms of PTSD may be more easily recognized, and that identifying reexperiencing and avoidance is particularly challenging.  相似文献   
9.
正目前,临床上对于直肠癌常用的影像评估方法有MRI、螺旋CT、PET-CT、直肠腔内超声(ERUS)等。而MRI作为首选检查方式,对肿瘤位置、浸润深度、淋巴结转移、血管侵犯、环周切缘及周围器官侵犯等方面的评估均具有明显优势~([1-2])。通过MRI诊断淋巴结的方法通常是影像科医师逐层浏览每一幅图像,从中识别淋巴结的形状、界限及密度来判断,这种传统方式耗时较长且存在主观偏倚,导致  相似文献   
10.
Aims: In neuropsychological evaluations, it is often difficult to ascertain whether poor performance on measures of validity is due to poor effort or malingering, or whether there is genuine cognitive impairment. Dunham and Denney created an algorithm to assess this question using the Medical Symptom Validity Test (MSVT). We assessed the ability of their algorithm to detect poor validity versus probable impairment, and concordance of failure on the MSVT with other freestanding tests of performance validity.

Methods: Two previously published datasets (n?=?153 and n?=?641, respectively) from outpatient neuropsychological evaluations were used to test Dunham and Denney’s algorithm, and to assess concordance of failure rates with the Test of Memory Malingering and the forced choice measure of the California Verbal Learning Test, two commonly used performance validity tests.

Results: In both datasets, none of the four cutoff scores for failure on the MSVT (70%, 75%, 80%, or 85%) identified a poor validity group with proportionally aligned failure rates on other freestanding measures of performance validity. Additionally, the protocols with probable impairment did not differ from those with poor validity on cognitive measures.

Conclusions: Despite what appeared to be a promising approach to evaluating failure on the easy MSVT subtests when clinical data are unavailable (as recommended in the advanced interpretation program, or advanced interpretation [AI], of the MSVT), the current findings indicate the AI remains the gold standard for doing so. Future research should build on this effort to address shortcomings in measures of effort in neuropsychological evaluations.  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