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   4910280篇
  免费   383583篇
  国内免费   16631篇
耳鼻咽喉   70694篇
儿科学   151708篇
妇产科学   130750篇
基础医学   730528篇
口腔科学   140949篇
临床医学   443905篇
内科学   896058篇
皮肤病学   115912篇
神经病学   413598篇
特种医学   194877篇
外国民族医学   1269篇
外科学   744691篇
综合类   144037篇
现状与发展   24篇
一般理论   2772篇
预防医学   407225篇
眼科学   117011篇
药学   352080篇
  25篇
中国医学   13066篇
肿瘤学   239315篇
  2021年   56303篇
  2019年   59104篇
  2018年   74743篇
  2017年   57295篇
  2016年   63938篇
  2015年   76669篇
  2014年   111549篇
  2013年   177153篇
  2012年   132973篇
  2011年   138590篇
  2010年   127510篇
  2009年   129334篇
  2008年   125828篇
  2007年   135267篇
  2006年   143527篇
  2005年   138486篇
  2004年   139221篇
  2003年   129879篇
  2002年   120480篇
  2001年   186911篇
  2000年   184440篇
  1999年   167147篇
  1998年   74924篇
  1997年   70331篇
  1996年   67923篇
  1995年   63720篇
  1994年   57867篇
  1993年   53623篇
  1992年   125673篇
  1991年   120442篇
  1990年   115585篇
  1989年   112637篇
  1988年   104805篇
  1987年   102870篇
  1986年   98099篇
  1985年   95650篇
  1984年   78295篇
  1983年   68919篇
  1982年   52276篇
  1981年   48343篇
  1980年   45520篇
  1979年   70607篇
  1978年   55272篇
  1977年   48721篇
  1976年   45013篇
  1975年   45928篇
  1974年   52526篇
  1973年   50429篇
  1972年   47675篇
  1971年   44025篇
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
111.
The aim of the study was to determine the effect of β-glucan on the cytotoxicity and genotoxicity of polypectomized patient's fecal water (FW). Polypectomized volunteers (n = 69) were randomly assigned to consume bread with or without β-glucan, for 3 months. FW was collected at the beginning (t = 0), the 30th and 90th day and 2 wk after the intervention. Cytotoxicity and genotoxicity were estimated on Caco-2 cells, using trypan blue exclusion test and comet assay, respectively. Gastrointestinal symptoms were recorded and subjects kept a 3-day food diary at baseline and after completion. Trypan blue exclusion test revealed cell survival of approximately 87% after incubation with FW. The FW samples showed 49% genotoxicity at the baseline. Genotoxicity in the intervention group decreased during the trial reaching statistical significance on the 90th day compared to control. An increase was noticed 2 wk after the trial, but it still remained significantly lower compared to control. Group-specific analysis for β-glucan also revealed significant decrease in the genotoxicity on the 90th day compared to baseline. β-glucan ingestion in polypectomized patients significantly decreased the genotoxicity of their FW. Our findings suggest that β-glucan consumption could possibly provide protection against colon cancer development.  相似文献   
112.
Platelet transfusions are a life-saving medical intervention used for the treatment of thrombocytopenia or hemorrhage. Extensive research has gone into trying to understand how to store platelets prior to the transfusion event. Much has been learned about storage bag materials, synthetic solutions, and how temperature impacts platelet viability and function. While room temperature storage of platelets preserves 24-hour in vivo platelet recovery and survival there is a greater risk for bacterial growth. Therefore, cold storage of platelets has become attractive due to the reduction in potential bacterial proliferation and the maintenance of platelet function beyond 5 days of storage. Cold stored platelets, however, have their own set of challenges. Cold stored platelets become activated through several mechanisms. The morphological and molecular changes that occur due to cold exposure enhance their ability to participate in the hemostatic process at the cost of rapid clearance from circulation. This review focuses on the underlying mechanisms leading to cold platelet activation and the receptor modifications involved in platelet clearance.  相似文献   
113.
INTRODUCTIONPsoriasis is a chronic inflammatory condition that affects the skin and joints, and is associated with cardiovascular risk factors, including metabolic syndrome (MetS). We aimed to assess the prevalence of MetS in patients with psoriasis and determine whether there was a correlation between psoriasis severity and MetS in a Singapore population.METHODSThis was a cross-sectional study of patients with psoriasis, aged 18–69 years, who attended a tertiary dermatology referral centre in Singapore from October 2007 to February 2009. Fasting glucose, lipids, blood pressure, Psoriasis Area and Severity Index, and body mass index were measured. MetS was diagnosed in the presence of three or more criteria of the modified National Cholesterol Education Program Adult Treatment Panel III.RESULTSAmong 338 patients with psoriasis, there were 238 (70.4%) men and 100 (29.6%) women, who were Chinese (n = 228; 67.5%), Malay (n = 52; 15.4%) and Indian (n = 58; 17.2%). The prevalence of MetS was 45.1%. MetS was 44% more prevalent in patients older than 50 years (p = 0.02). Malay patients with psoriasis were significantly more likely to have hypertriglyceridaemia, elevated fasting plasma glucose and abdominal obesity. There was no significant correlation between psoriasis severity and risk of MetS.CONCLUSIONThe prevalence of MetS in patients with psoriasis in Singapore was 45.1%, or nearly threefold higher than the Singapore general population. Patients with psoriasis should be screened yearly for MetS and any modifiable cardiovascular risk factors should be actively controlled.  相似文献   
114.
European Journal of Orthopaedic Surgery & Traumatology - The goals of this study were to compare patient satisfaction and wound-related complications in patients receiving 2-octyl cyanoacrylate...  相似文献   
115.
116.
117.
Graefe's Archive for Clinical and Experimental Ophthalmology - To evaluate the long-term safety and efficacy of intrastromal bevacizumab for treatment of deep corneal neovascularization in...  相似文献   
118.
ABSTRACT

Purpose

To investigate the expression of IL-11 and its receptor IL-11Rα and to quantify density of CD163+ M2 macrophages in proliferative diabetic retinopathy (PDR).  相似文献   
119.
120.
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