首页 | 官方网站   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   44411篇
  免费   2181篇
  国内免费   105篇
医药卫生   46697篇
  2025年   143篇
  2024年   435篇
  2023年   754篇
  2022年   1187篇
  2021年   1552篇
  2020年   1460篇
  2019年   3451篇
  2018年   3032篇
  2017年   1714篇
  2016年   910篇
  2015年   951篇
  2014年   2337篇
  2013年   2036篇
  2012年   2245篇
  2011年   2311篇
  2010年   1915篇
  2009年   1624篇
  2008年   1488篇
  2007年   1307篇
  2006年   1217篇
  2005年   798篇
  2004年   601篇
  2003年   490篇
  2002年   343篇
  2001年   304篇
  2000年   265篇
  1999年   243篇
  1998年   204篇
  1997年   209篇
  1996年   161篇
  1995年   135篇
  1994年   116篇
  1993年   50篇
  1992年   23篇
  1991年   29篇
  1990年   22篇
  1989年   18篇
  1985年   852篇
  1984年   1390篇
  1983年   1111篇
  1982年   1099篇
  1981年   1102篇
  1980年   955篇
  1979年   844篇
  1978年   660篇
  1977年   464篇
  1976年   632篇
  1975年   552篇
  1974年   469篇
  1973年   430篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
2.
The goals of this report are: 1) to review the number needed to treat (NNT) concept, which, although well established in many sectors of medicine, is still relatively new to the radiotherapy community; 2) to discuss several clinical radiotherapy examples illustrating the inherent advantages of the NNT approach; and 3) to discuss potential future roles of the NNT concept within radiotherapy.  相似文献   
3.
The 1st Japanese Urological Association-Japanese Society of Medical Oncology Joint Conference, titled 'A step towards better collaboration between urologists and medical oncologists', was held to coincide with the 44th Meeting of the Japan Society of Clinical Oncology, Tokyo, in October 2006. The main theme of the conference addressed the need for a subspecialty of medical oncologist within urology to keep abreast of advances in medical oncology. Urologists should become more involved in the postoperative management of urologic cancer. Consensus on the optimal way to move forward in the treatment of urological cancer is needed. The conference featured eight lectures surveying the present status of uro-oncology in Europe, the USA, Korea, Singapore, and Japan; the relationship between surgical oncologists and medical oncologists; global trends and international clinical trials in uro-oncology; and the future of urologic oncology. These were followed by a general discussion titled 'Achieving better collaboration between the surgical oncologist and the medical oncologist.' This report presents a roundup of the 1st Japanese Urological Association-Japanese Society of Medical Oncology Joint Conference.  相似文献   
4.
回顾医学美学与美容医学形成独立的学科系统的十多年来的发展历程,认为这个新兴学科在“整体学科”方面还存在一些学术问题有待人们进一步探讨。并认为,所谓“整体学科研究”是遵循该学科发展的内在规律所进行的各项研究的总和,是该学科发展的灵魂。学者们的任务在于:通过“整体学科研究”寻求其学科内在规律,经一代代同道有志者坚持不懈的努力,达到学科完善的目的。  相似文献   
5.
Lymphoma arising in an adenolymphoma   总被引:1,自引:0,他引:1  
G Hall  H Tesluk  S Baron 《Human pathology》1985,16(4):424-427
A malignant lymphoma that originated in association with an adenolymphoma (Warthin's tumor) of the parotid salivary gland is reported. The occurrence of lymphomas in salivary glands is discussed briefly.  相似文献   
6.
Arterial spasm was induced by application of calcium chloride to the adventitial surface of the rabbit common carotid artery in vivo. Sodium chloride (NaCl) was applied to the contralateral vessel as control. Vessels were fixed in situ by intravascular perfusion after 15 min, 1 hr, or 24 hr and prepared for light and scanning electron microscopy (SEM). With SEM, the luminal surface at the site of calcium application showed severe longitudinal folding accompanied by endothelial desquamation with extensive platelet deposition on exposed subendothelium. The luminal cross-sectional area was reduced by 53 +/- 19.5% after 15 min and by 44 +/- 12% after 1 hr as compared with the contralateral control. Furthermore, the luminal area at the site of calcium application was found to be reduced by 42 +/- 8% after 1 hr when compared with segments of the same vessel distal to the site of calcium application. Blood flow rate, as measured by electromagnetic flow probe, was not reduced. Vessels examined after 24 hr showed a significant increase in luminal cross-sectional area as compared with contralateral control vessels (136 +/- 70%). Control vessels (NaCl) showed no significant change in luminal cross-sectional area and no endothelial desquamation or platelet deposition after 15 min, 1 hr, or 24 hr. Examination of histologic sections showed calcium precipitation within the attached thrombus after 15 min with calcium deposits also adherent to the adjacent luminal aspect of the internal elastic lamina (IEL). By 24 hr, this precipitation extended throughout the media. Marked deposition of leukocytes was seen after 24 hr which showed a preferential attachment for areas of endothelial damage and discontinuity of IEL.  相似文献   
7.
The Waorani Indians of eastern Ecuador have the highest blood concentration of IgE reported in a human population. Evidence obtained by medical history, physical examination, and immediate hypersensitivity skin tests suggests that pollen allergy and other atopic diseases are rare among the Waorani. A similar association between parasite-induced hyperimmunoglobulinemia-E and a low prevalence of conventional atopic disease has been reported in numerous other tropical populations. Saturation of mast cell IgE receptors with antibodies directed to the parasite and/or other antigens and competitive inhibition of passive binding of pollen allergen-specific IgE is one hypothetical cause of this association. We have tested this interesting conjecture by passively sensitizing the skin of Waorani Indians with serum containing pollen allergen-specific IgE antibodies. Waorani Indians with hyperimmunoglobulinemia-E can be adoptively sensitized with human ragweed or rye grass hyperimmune IgE antisera. This suggests that the cutaneous mast cells of healthy Waorani have active IgE receptors. The high circulating plasma concentrations of IgE in the Waorani do not prevent adoptive cutaneous sensitization with pollen-specific IgE antibodies.  相似文献   
8.
Several recent reports have described cases of acute nonlymphocytic leukemia with a unique chromosome translocation, t(6;9)(p23;q34). We have studied three additional patients who have acute nonlymphocytic leukemia and t(6;9)(p23;q34). Our findings provide additional support for the suggestion that this translocation is yet another distinct cytogenetic abnormality associated with myeloproliferative disorders.  相似文献   
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

京公网安备 11010802026262号