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   1442243篇
  免费   109797篇
  国内免费   4756篇
耳鼻咽喉   18166篇
儿科学   46330篇
妇产科学   38383篇
基础医学   211676篇
口腔科学   38299篇
临床医学   140324篇
内科学   280083篇
皮肤病学   27876篇
神经病学   121340篇
特种医学   52609篇
外国民族医学   366篇
外科学   201911篇
综合类   30425篇
现状与发展   2篇
一般理论   623篇
预防医学   124468篇
眼科学   31476篇
药学   106467篇
  8篇
中国医学   3324篇
肿瘤学   82640篇
  2021年   12923篇
  2019年   13544篇
  2018年   18667篇
  2017年   13966篇
  2016年   15035篇
  2015年   17344篇
  2014年   23969篇
  2013年   37037篇
  2012年   51306篇
  2011年   54450篇
  2010年   31321篇
  2009年   28780篇
  2008年   49461篇
  2007年   52311篇
  2006年   52074篇
  2005年   50600篇
  2004年   48328篇
  2003年   45853篇
  2002年   44480篇
  2001年   61899篇
  2000年   63348篇
  1999年   53380篇
  1998年   15918篇
  1997年   14357篇
  1996年   14143篇
  1995年   13450篇
  1994年   12481篇
  1993年   11746篇
  1992年   42247篇
  1991年   41448篇
  1990年   40047篇
  1989年   37937篇
  1988年   35195篇
  1987年   34279篇
  1986年   32769篇
  1985年   31322篇
  1984年   23776篇
  1983年   20286篇
  1982年   12688篇
  1981年   11223篇
  1979年   21315篇
  1978年   15356篇
  1977年   12560篇
  1976年   12315篇
  1975年   12483篇
  1974年   15198篇
  1973年   14846篇
  1972年   13598篇
  1971年   12687篇
  1970年   11715篇
排序方式: 共有10000条查询结果,搜索用时 265 毫秒
71.
72.
73.
Nevo  N.  Goldstein  A. L.  Staierman  M.  Eran  N.  Carmeli  I.  Rayman  S.  mnouskin  Y. 《Hernia》2022,26(6):1491-1499
Hernia - The minimally invasive surgical repair of combined inguinal and ventral hernias often requires shifting from one approach or plane to another. The traditional enhanced-view totally...  相似文献   
74.
Context: Persons with spinal cord injury (SCI) experience significant challenges when they access primary care and community services.

Design: A provincial summit was held to direct research, education, and innovation for primary and community care for SCI.

Setting: Toronto, Ontario, Canada.

Participants: Key stakeholders (N?=?95) including persons with SCI and caregivers, clinicians from primary care, rehabilitation, and specialized care, researchers, advocacy groups, and policy makers.

Methods: A one-day facilitated meeting that included guest speakers, panel discussions and small group discussions was held to generate potential solutions to current issues related to SCI care and to foster collaborative relationships to advance care for SCI. Perspectives on SCI management were shared by primary care, neurosurgery, rehabilitation, and members of the SCI community

Outcome Measures: Discussions were focused on five domains: knowledge translation and dissemination, application of best practices, communication, research, and patient service accessibility.

Results: Summit participants identified issues and prioritized solutions to improve primary and community care including the creation of a network of key stakeholders to enable knowledge creation and dissemination; an online repository of SCI resources, integrated health records, and a clinical network for SCI care; development and implementation of strategies to improve care transitions across sectors; implementation of effective care models and improved access to services; and utilization of empowerment frameworks to support self-management.

Conclusions: This summit identified priorities for further collaborative efforts to advance SCI primary and community care and will inform the development of a provincial SCI strategy aimed at improving the system of care for SCI.  相似文献   
75.
76.
77.
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   
78.
79.
Thermal ablation of liver tumors near large blood vessels is affected by the cooling effect of blood flow, leading to incomplete ablation. Hence, we conducted a comparative investigation of heat sink effect in monopolar (MP) and bipolar (BP) radiofrequency ablation (RFA), and microwave (MW) ablation devices.With a perfused calf liver, the ablative performances (volume, mass, density, dimensions), with and without heat sink, were measured. Heat sink was present when the ablative tip of the probes were 8.0 mm close to a major hepatic vein and absent when >30 mm away. Temperatures (T1 and T2) on either side of the hepatic vein near the tip of the probes, heating probe temperature (T3), outlet perfusate temperature (T4), and ablation time were monitored.With or without heat sink, BP radiofrequency ablated a larger volume and mass, compared with MP RFA or MW ablation, with latter device producing the highest density of tissue ablated. MW ablation produced an ellipsoidal shape while radiofrequency devices produced spheres.Percentage heat sink effect in Bipolar radiofrequency : Mono-polar radiofrequency : Microwave was (Volume) 33:41:22; (mass) 23:56:34; (density) 9.0:26:18; and (relative elipscity) 5.8:12.9:1.3, indicating that BP and MW devices were less affected.Percentage heat sink effect on time (minutes) to reach maximum temperature (W) = 13.28:9.2:29.8; time at maximum temperature (X) is 87:66:16.66; temperature difference (Y) between the thermal probes (T3) and the temperature (T1 + T2)/2 on either side of the hepatic vessel was 100:87:20; and temperature difference between the (T1 + T2)/2 and temperature of outlet circulating solution (T4), Z was 20.33:30.23:37.5.MW and BP radiofrequencies were less affected by heat sink while MP RFA was the most affected. With a single ablation, BP radiofrequency ablated a larger volume and mass regardless of heat sink.  相似文献   
80.
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