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   148166篇
  免费   32418篇
  国内免费   2391篇
耳鼻咽喉   5168篇
儿科学   5358篇
妇产科学   2385篇
基础医学   2993篇
口腔科学   1488篇
临床医学   26520篇
内科学   46809篇
皮肤病学   7395篇
神经病学   14639篇
特种医学   6338篇
外科学   40746篇
综合类   241篇
现状与发展   72篇
一般理论   1篇
预防医学   6952篇
眼科学   3320篇
药学   896篇
中国医学   10篇
肿瘤学   11644篇
  2024年   514篇
  2023年   4789篇
  2022年   1158篇
  2021年   3071篇
  2020年   6017篇
  2019年   2152篇
  2018年   7362篇
  2017年   7314篇
  2016年   8388篇
  2015年   8378篇
  2014年   15442篇
  2013年   15547篇
  2012年   5362篇
  2011年   5361篇
  2010年   10291篇
  2009年   14173篇
  2008年   5688篇
  2007年   3920篇
  2006年   6389篇
  2005年   3674篇
  2004年   2953篇
  2003年   1925篇
  2002年   2015篇
  2001年   3783篇
  2000年   2999篇
  1999年   3196篇
  1998年   3628篇
  1997年   3452篇
  1996年   3355篇
  1995年   3195篇
  1994年   1938篇
  1993年   1568篇
  1992年   1355篇
  1991年   1414篇
  1990年   1056篇
  1989年   1175篇
  1988年   1014篇
  1987年   837篇
  1986年   886篇
  1985年   717篇
  1984年   543篇
  1983年   514篇
  1982年   508篇
  1981年   392篇
  1980年   355篇
  1979年   308篇
  1978年   329篇
  1977年   396篇
  1975年   279篇
  1972年   280篇
排序方式: 共有10000条查询结果,搜索用时 447 毫秒
61.
62.
63.
64.
Breast elastography has been available for more than 15 years but is not widely incorporated into clinical practice. Many publications report extremely high accuracy for various breast elastographic techniques. However, results in the literature are extremely variable. This variability is most likely due to variations in technique, a relatively steep learning curve, and variability in methods between vendors. This article describes our protocol for performing breast elastography using both strain elastography and shear wave elastography, which produces high sensitivity and specificity. Additionally, we will describe the most commonly known false-positive and false-negative lesions as well as how to detect them.  相似文献   
65.
The term “oligometastatic prostate cancer” refers to a heterogeneous group of disease states currently defined solely on the basis of clinical features. Oligorecurrent disease, de novo oligometastases, and oligoprogressive disease likely have unique biologic underpinnings and natural histories. Evidence suggesting the existence of a subset of patients who harbor prostate cancer with limited metastatic potential currently includes disparate and overwhelmingly retrospective reports. Nevertheless, emerging prospective data have corroborated the “better-than-expected,” retrospectively observed outcomes, particularly in the setting of oligorecurrent prostate cancer. Improved functional imaging with prostate-specific membrane antigen-targeted strategies may enhance the identification of patients with oligometastatic prostate cancer in the short term. In the long term, refinement of the oligometastatic case definition likely will require biologic risk-stratification schemes. To determine optimal treatment strategies and identify patients most likely to benefit from metastasis-directed therapy, future efforts should focus on conducting high-quality, prospective trials with much-needed molecular correlative studies.  相似文献   
66.
67.
68.
Doxorubicin (DOX) is the most commonly used anticancer drug; however, it has limited use because prolonged administration may result in severe cardiotoxicity. Simvastatin (SIM), generally prescribed for hypercholesterolaemia, has also shown salubrious results in the monotherapy or combinational drug therapy of different cancers in various models. Nanoparticle drug delivery systems are a novel way of improving therapeutics and also improving the absorption and specificity of drugs towards tumour cells. In this study, we exploited this technology to increase drug specificity and minimize imminent adverse effects. In this study, the antitumour activity of the combination formulas of DOX and SIM, either loaded in water (DOX‐SIM‐Solution) or nanoemulsions (NEs) (DOX‐SIM‐NE), was evaluated in a Swiss albino mouse model of Ehrlich ascites carcinoma. The anticancer effect was assessed by quantifying the change in body weight, mean survival time, and percent increase in lifespan (%ILS), determining haematological and serum biochemical parameters (liver function test, kidney function test and lipid profile parameters) as well as studying the histopathological alterations in liver tissues. We observed a clear increase in %ILS of the DOX‐SIM‐Solution group (265.30) that was double the %ILS of the DOX‐SIM‐NE group (134.70). However, DOX‐SIM‐NE had a non‐toxic effect on the haematological parameters, whereas DOX‐SIM‐Solution increased the levels of haemoglobin and lymphocytes. Furthermore, the encapsulation of SIM and DOX into NEs improved the levels of all serum biochemical parameters compared to the DOX‐SIM‐Solution. A reduction in the side effects of DOX‐SIM‐NE on the liver was also established using light microscopy, which revealed that the morphologies of the hepatocytes of the mice were less affected by administration of the DOX‐SIM‐NE treatment than with the DOX‐SIM‐Solution treatment. The study showed that incorporating SIM into the DOX‐loaded‐NE formulation remarkably improved its efficiency and simultaneously reduced its adverse effects.  相似文献   
69.
70.
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