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   30687篇
  免费   2014篇
  国内免费   116篇
耳鼻咽喉   469篇
儿科学   874篇
妇产科学   560篇
基础医学   4804篇
口腔科学   851篇
临床医学   3015篇
内科学   6268篇
皮肤病学   745篇
神经病学   3222篇
特种医学   1066篇
外科学   3238篇
综合类   191篇
一般理论   22篇
预防医学   2377篇
眼科学   804篇
药学   2034篇
中国医学   98篇
肿瘤学   2179篇
  2023年   210篇
  2022年   191篇
  2021年   791篇
  2020年   544篇
  2019年   781篇
  2018年   851篇
  2017年   670篇
  2016年   795篇
  2015年   927篇
  2014年   1093篇
  2013年   1415篇
  2012年   2157篇
  2011年   2341篇
  2010年   1258篇
  2009年   1131篇
  2008年   1898篇
  2007年   1926篇
  2006年   1847篇
  2005年   1741篇
  2004年   1637篇
  2003年   1489篇
  2002年   1244篇
  2001年   533篇
  2000年   446篇
  1999年   444篇
  1998年   327篇
  1997年   258篇
  1996年   191篇
  1995年   174篇
  1994年   151篇
  1993年   100篇
  1992年   204篇
  1991年   183篇
  1990年   204篇
  1989年   182篇
  1988年   151篇
  1987年   145篇
  1986年   122篇
  1985年   127篇
  1984年   97篇
  1983年   95篇
  1982年   66篇
  1980年   68篇
  1979年   94篇
  1978年   76篇
  1977年   85篇
  1975年   62篇
  1974年   61篇
  1973年   63篇
  1972年   84篇
排序方式: 共有10000条查询结果,搜索用时 218 毫秒
1.
Die Anaesthesiologie - Die Anlage einer Magensonde im OP oder auf einer Intensivstation (ITS) stellt eine alltäglich durchgeführte Prozedur dar. Obwohl die Sonde häufig durch...  相似文献   
2.
Abstract

Oocyte maturation defect is a challenging situation in the management of infertility, the etiology may be related to endocrine causes, protocols used in ovarian stimulation, oocyte intrinsic defects or procedures in embryology laboratory. We report three Mexican females in treatment for primary infertility with non-mature oocytes after ovary stimulation and oocyte capture in whom a genetic diagnosis of TUBB8-oocyte maturation defect was revealed by exome sequencing. Two couples achieved pregnancies though oocyte donation after establishing the genetic etiology. Our results expand the role of TUBB8-disorders in patients of non-Asian ethnicity. Oocyte maturation defects of monogenic origin are a growing group of disorders that endocrinologists and reproductive medicine specialists should be aware in order to provide referral to genetics for establish a correct and opportune diagnosis.  相似文献   
3.
4.
Red cell exchange (RCE) is a common procedure in adults with sickle cell disease (SCD). Implantable dual lumen Vortex (DLV) ports can be used for RCE in patients with poor peripheral venous access. We performed a retrospective cohort study of RCE procedures performed in adults with SCD. The main objective of the study was to compare the inlet speed, duration of procedures and rate of complications performed through DLV ports to those performed through temporary central venous and peripheral catheters. Twenty‐nine adults with SCD underwent a total of 318 RCE procedures. Twenty adults had DLV ports placed and 218 procedures were performed using DLV ports. Mean length of follow‐up after DLV port placement was 397 ± 263 days. Six DLV ports were removed due to infection and 1 for malfunction after a mean of 171 ± 120 days. Compared to temporary central venous and peripheral catheters, DLV port procedures had a greater rate of procedural complications, a longer duration, and a lower inlet speed (all P < 0.01). When accounting for the maximum allowable inlet speed to avoid citrate toxicity, 40% of DLV port procedures were greater than 10% below maximum speed, compared to 7 and 14% of procedures performed through temporary central venous and peripheral catheters (P < 0.0001). In conclusion, DLV ports can be used for RCE in adults with SCD, albeit with more procedural complications and longer duration. The smaller internal diameter and longer catheter of DLV ports compared to temporary central venous catheters likely accounts for the differences noted. J. Clin. Apheresis 30:353–358, 2015. © 2015 Wiley Periodicals, Inc.  相似文献   
5.
6.
7.

Introduction

Little is known about dementia incidence in diverse populations of oldest-old, the age group with highest dementia incidence.

Methods

Incident dementia diagnoses from 1/1/2010 to 9/30/2015 were abstracted from medical records for 2350 members of an integrated health care system in California (n = 1702 whites, n = 375 blacks, n = 105 Latinos, n = 168 Asians) aged ≥90 in 2010. We estimated race/ethnicity-specific age-adjusted dementia incidence rates and implemented Cox proportional hazards models and Fine and Gray competing risk of death models adjusted for demographics and comorbidities in midlife and late-life.

Results

Dementia incidence rates (n = 771 cases) were lowest among Asians (89.9/1000 person-years), followed by whites (96.9/1000 person-years), Latinos (105.8/1000 person-years), and blacks (121.5/1000 person-years). Cox regression and competing risk models estimated 28% and 36% higher dementia risk for blacks versus whites adjusting for demographics and comorbidities.

Discussion

Patterns of racial/ethnic disparities in dementia seen in younger older adults continue after the age of 90 years, though smaller in magnitude.  相似文献   
8.
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