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   20913篇
  免费   1464篇
  国内免费   85篇
耳鼻咽喉   192篇
儿科学   572篇
妇产科学   501篇
基础医学   2565篇
口腔科学   472篇
临床医学   2305篇
内科学   3968篇
皮肤病学   197篇
神经病学   2120篇
特种医学   693篇
外国民族医学   3篇
外科学   3441篇
综合类   261篇
一般理论   16篇
预防医学   1748篇
眼科学   497篇
药学   1589篇
中国医学   17篇
肿瘤学   1305篇
  2023年   91篇
  2022年   173篇
  2021年   342篇
  2020年   228篇
  2019年   371篇
  2018年   437篇
  2017年   317篇
  2016年   342篇
  2015年   421篇
  2014年   610篇
  2013年   897篇
  2012年   1383篇
  2011年   1455篇
  2010年   821篇
  2009年   688篇
  2008年   1383篇
  2007年   1590篇
  2006年   1362篇
  2005年   1365篇
  2004年   1412篇
  2003年   1233篇
  2002年   1225篇
  2001年   232篇
  2000年   181篇
  1999年   238篇
  1998年   285篇
  1997年   239篇
  1996年   193篇
  1995年   163篇
  1994年   149篇
  1993年   155篇
  1992年   175篇
  1991年   157篇
  1990年   132篇
  1989年   119篇
  1988年   106篇
  1987年   123篇
  1986年   111篇
  1985年   94篇
  1984年   112篇
  1983年   109篇
  1982年   106篇
  1981年   102篇
  1980年   94篇
  1979年   88篇
  1978年   79篇
  1977年   67篇
  1976年   77篇
  1975年   74篇
  1972年   68篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
1.
2.
Young children enter kindergarten with varying levels of readiness and abilities to learn. One factor that contributes to lower levels of school readiness is poverty. One timely, cost-effective, and feasible strategy to boost school readiness, regardless of exposure to high-quality preschool is to leverage the summer months prior to kindergarten entry and provide comprehensive, evidence-based programming immediately before the school year begins. The current study implemented a community-based summer programme targeted at improving school readiness for 25 four- and five-year-old children in a low-income community. Across the 9-week study, children participated in two types of early literacy activities and the Incredible Years social/emotional learning curriculum. Results indicate that participants demonstrated significant growth across three early literacy skills and were rated as overall stable regarding their behaviour across the summer. These results are discussed along with implications and future directions in this line of research.  相似文献   
3.
4.
Wound healing involves a number of cellular and molecular events, many of which are controlled by soluble growth factors. In the process of healing, hepatocyte growth factor, a cytokine known to act as mitogen, motogen, and morphogen, has been postulated to play multiple roles during several stages of this complex biological process. Produced primarily by stromal fibroblasts, hepatocyte growth factor regulates angiogenesis, vascular permeability, cell migration, matrix deposition and degradation, and other biological processes. The current article discusses recent progress in understanding the multiple roles played by this growth factor in tissue repair.  相似文献   
5.
6.
L D Keith  J C Crabbe 《Alcohol》1992,9(6):529-533
The intent of this study was to determine whether chronic ethanol (EtOH) vapor inhalation, with or without adjunct pyrazole (PYR) administration, was stressful in mice, as defined by increases in plasma corticosterone (CORT) concentration. Mice were randomly assigned to groups differentiated both on the basis of EtOH vapor exposure and the presence or absence of PYR administration. Blood samples for blood EtOH concentration (BEC) and plasma CORT concentration were obtained from mice after 72-96 hours of treatment. Mice were sacrificed after 96 hours of treatment and body and adrenal weight determined. BEC was significantly higher in PYR-treated animals and animals treated with the higher EtOH vapor concentration. Plasma CORT was elevated in proportion to BEC; however, other nonspecific stresses, in particular that of PYR administration, also elevated plasma CORT. Nonspecific stresses associated with this protocol may reduce the generality of these observations. Nevertheless, the high correlation between BEC and plasma CORT concentration in the PYR groups indicates that, with suitable control groups, the PYR-EtOH vapor inhalation approach is viable for studies concerned with EtOH effects on hypothalamic-anterior pituitary-adrenocortical function.  相似文献   
7.
8.
9.
Surgical intervention may be necessary for some patients with specific pathology or derangement of the temporomandibular joint as part of an overall management protocol. The current literature discusses the efficacy of arthroscopy, the treatment of the difficult problem of ankylosis, and the use of implants and autogenous and allogenic materials to replace the disk.  相似文献   
10.
Phytochemical-mediated modulation of P-glycoprotein (P-gp) and other drug transporters may give rise to many herb-drug interactions. Serial plasma concentration-time profiles of the P-gp substrate, digoxin, were used to determine whether supplementation with goldenseal or kava kava modified P-gp activity in vivo. Twenty healthy volunteers were randomly assigned to receive a standardized goldenseal (3210 mg daily) or kava kava (1227 mg daily) supplement for 14 days, followed by a 30-day washout period. Subjects were also randomized to receive rifampin (600 mg daily, 7 days) and clarithromycin (1000 mg daily, 7 days) as positive controls for P-gp induction and inhibition, respectively. Digoxin (Lanoxin, 0.5 mg) was administered p.o. before and at the end of each supplementation and control period. Serial digoxin plasma concentrations were obtained over 24 h and analyzed by chemiluminescent immunoassay. Comparisons of area under the curve (AUC)((0-3)), AUC((0-24)), C(max,) CL/F, and elimination half-life were used to assess the effects of goldenseal, kava kava, rifampin, and clarithromycin on digoxin pharmacokinetics. Rifampin produced significant reductions (p < 0.01) in AUC((0-3)), AUC((0-24)), CL/F, t(1/2), and C(max), whereas clarithromycin increased these parameters significantly (p < 0.01). With the exception of goldenseal's effect on C(max) (14% increase), no statistically significant effects on digoxin pharmacokinetics were observed following supplementation with either goldenseal or kava kava. When compared with rifampin and clarithromycin, supplementation with these specific formulations of goldenseal or kava kava did not appear to affect digoxin pharmacokinetics, suggesting that these supplements are not potent modulators of P-gp in vivo.  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