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   7198篇
  免费   516篇
  国内免费   29篇
耳鼻咽喉   126篇
儿科学   197篇
妇产科学   191篇
基础医学   958篇
口腔科学   161篇
临床医学   500篇
内科学   1830篇
皮肤病学   235篇
神经病学   586篇
特种医学   233篇
外科学   1122篇
综合类   39篇
一般理论   1篇
预防医学   598篇
眼科学   109篇
药学   377篇
中国医学   34篇
肿瘤学   446篇
  2023年   40篇
  2022年   30篇
  2021年   173篇
  2020年   115篇
  2019年   212篇
  2018年   253篇
  2017年   175篇
  2016年   189篇
  2015年   203篇
  2014年   295篇
  2013年   385篇
  2012年   477篇
  2011年   511篇
  2010年   315篇
  2009年   312篇
  2008年   431篇
  2007年   446篇
  2006年   435篇
  2005年   431篇
  2004年   350篇
  2003年   366篇
  2002年   307篇
  2001年   143篇
  2000年   180篇
  1999年   168篇
  1998年   46篇
  1997年   52篇
  1996年   35篇
  1995年   27篇
  1994年   22篇
  1993年   31篇
  1992年   74篇
  1991年   60篇
  1990年   73篇
  1989年   54篇
  1988年   38篇
  1987年   43篇
  1986年   41篇
  1985年   38篇
  1984年   27篇
  1983年   19篇
  1982年   12篇
  1981年   9篇
  1980年   9篇
  1979年   8篇
  1978年   9篇
  1977年   8篇
  1976年   8篇
  1975年   10篇
  1971年   13篇
排序方式: 共有7743条查询结果,搜索用时 31 毫秒
1.
The coronavirus disease 2019, which is caused by severe acute respiratory syndrome coronavirus 2, was first identified in December 2019 in Wuhan, China, and has since spread rapidly, evolving into a full-blown pandemic. We would like to report our experience after 1 year of this pandemic in the surgical service of a district hospital in Spain. There have been many changes (including new protocols) that our service and the hospital have undergone, to adapt to the new situation. We believe that this experience can be useful for other professionals who have lived and are living a similar situation.  相似文献   
2.
IntroductionThe current paradigm of the management of rheumatoid arthritis (RA) recommends achieving a state of remission or low disease activity through the treat-to-target strategy. Our study assesses adherence to this strategy.MethodPatients with RA (ACR-EULAR 2010 criteria) were included. From each centre, 19 patients were randomly selected. Clinical histories (CH) were assessed by independent auditors, checking compliance with predefined quality criteria. The study was approved by ethics committees.ResultsWe included 856 patients (mean age 54 years; 71% women). The use of a combined index (CI) was recorded in 61% of cases. Visits were recorded every 4 weeks using a CI in 4% of CH while attempts were made to achieve remission. Monitoring of disease activity every 6–8 months after reaching the target was recorded in 73% of cases.ConclusionsThe implementation of the treat-to-target strategy is barely recorded in patients with RA in routine clinical practice.  相似文献   
3.
4.
5.
IntroductionLarge variability among Alzheimer's disease (AD) cases might impact genetic discoveries and complicate dissection of underlying biological pathways.MethodsGenome Research at Fundacio ACE ([email protected]) is a genome-wide study of dementia and its clinical endophenotypes, defined based on AD's clinical certainty and vascular burden. We assessed the impact of known AD loci across endophenotypes to generate loci categories. We incorporated gene coexpression data and conducted pathway analysis per category. Finally, to evaluate the effect of heterogeneity in genetic studies, [email protected] series were meta-analyzed with additional genome-wide association study data sets.ResultsWe classified known AD loci into three categories, which might reflect the disease clinical heterogeneity. Vascular processes were only detected as a causal mechanism in probable AD. The meta-analysis strategy revealed the ANKRD31-rs4704171 and NDUFAF6-rs10098778 and confirmed SCIMP-rs7225151 and CD33-rs3865444.DiscussionThe regulation of vasculature is a prominent causal component of probable AD. [email protected] meta-analysis revealed novel AD genetic signals, strongly driven by the presence of clinical heterogeneity in the AD series.  相似文献   
6.

Objective

To examine the association of placental levels of arsenic (As), cadmium (Cd), mercury (Hg), lead (Pb), manganese (Mn), and chromium (Cr) with birth outcomes (birth weight, length, and head circumference, low birth weight [LBW], gestational age, preterm delivery, and small for gestational age [SGA]) in mother-child pairs from the Environment and Childhood (INMA) Project in Spain.

Methods

Metal concentrations were measured in placenta tissue samples randomly selected from five INMA cohorts. Data on birth outcomes were obtained from medical records. Associations were assessed in a sub-sample of 327 mother-infant pairs by regression models adjusted for confounding factors and for all metals simultaneously. Effect modification by sex was also evaluated.

Results

Elevated placental Cd levels (>5.79 vs. <3.30?ng/g) were associated with reduced birth weight (?111.8?g, 95%CI?=??215.6; ?8.06, p-trend?=?0.01) and length (?0.62?cm, 95%CI?=??1.20; ?0.04, p-trend?=?0.02), while a 10% increase in Cd was associated with 1.21-fold increased odds (95%CI?=?1.01; 1.43) of LBW in the global sample but with 14% lower odds (95%CI?=?0.78; 0.96) of preterm delivery in males (Pinteraction?=?0.10). Detected (vs. undetected) Hg was associated with reduced head circumference (?0.49?cm, 95%CI?=??1.00; 0.03) in females (Pinteraction?=?0.03). A 10% increase in placental Mn was associated with slight increases in gestational age (0.04 weeks, 95%CI?=?0.01; 0.07) in the global sample and in head circumference (0.05?cm, 95%CI?=??0.01; 0.10) in females (Pinteraction?=?0.03). Elevated Cr levels (>99.6 vs. <56.1?ng/g) were associated with reduced birth length (?0.68?cm, 95%CI?=??1.33; ?0.04, p-trend?=?0.02) and slightly increased gestational age (0.35 weeks, 95%CI?=??0.07; 0.77, p-trend?=?0.08) in the global sample. As and Pb were detected in few placentas (27% and 13%, respectively) and were not associated with any studied birth outcome.

Conclusions

Data suggest that in utero exposure to Cd, Hg, and Cr could adversely affect fetal growth, whereas Mn and Cr appear to have a positive effect on gestational age. Given the relatively small number of subjects, sex-specific associations should be interpreted with caution.  相似文献   
7.
8.
Archives of Gynecology and Obstetrics - To evaluate the long-term pediatric neuropsychiatric morbidity of children born to obese patients. A population-based cohort analysis was performed comparing...  相似文献   
9.
10.
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