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   4908篇
  免费   193篇
  国内免费   27篇
耳鼻咽喉   81篇
儿科学   115篇
妇产科学   192篇
基础医学   489篇
口腔科学   57篇
临床医学   361篇
内科学   1316篇
皮肤病学   86篇
神经病学   680篇
特种医学   151篇
外科学   731篇
综合类   8篇
一般理论   2篇
预防医学   147篇
眼科学   153篇
药学   226篇
中国医学   22篇
肿瘤学   311篇
  2023年   46篇
  2022年   75篇
  2021年   151篇
  2020年   96篇
  2019年   106篇
  2018年   143篇
  2017年   95篇
  2016年   123篇
  2015年   119篇
  2014年   195篇
  2013年   232篇
  2012年   372篇
  2011年   351篇
  2010年   212篇
  2009年   205篇
  2008年   325篇
  2007年   292篇
  2006年   276篇
  2005年   291篇
  2004年   234篇
  2003年   219篇
  2002年   200篇
  2001年   72篇
  2000年   61篇
  1999年   62篇
  1998年   40篇
  1997年   28篇
  1996年   33篇
  1995年   39篇
  1994年   28篇
  1993年   13篇
  1992年   41篇
  1991年   49篇
  1990年   27篇
  1989年   33篇
  1988年   35篇
  1987年   25篇
  1986年   20篇
  1985年   20篇
  1984年   26篇
  1983年   17篇
  1982年   8篇
  1981年   9篇
  1980年   13篇
  1979年   10篇
  1978年   8篇
  1977年   7篇
  1975年   5篇
  1974年   7篇
  1965年   3篇
排序方式: 共有5128条查询结果,搜索用时 15 毫秒
1.
2.
3.
OBJECTIVE: To verify whether immunohistochemistry might be useful in the distinction between a true laterocervical metastasis of an undetected thyroid carcinoma and a primary tumor outside the gland. DESIGN: Galectin-3, cytokeratin 19, and HBME-1 were assessed in six cases (group A) of laterocervical masses harboring papillary thyroid carcinoma (PTC) but without a thyroid tumor, and in eight cases (group B) showing PTC both in the thyroid and in the laterocervical masses. In both groups, normal-looking follicles adjacent to the laterocervical neoplasia were present. MAIN OUTCOME: We found that the apparently normal follicles in group A were negative for all the antibodies, while group B showed strong and diffuse positive immunostaining. The neoplastic areas were always positive for all the antibodies in both groups. CONCLUSION: Even if immunohistochemical patterns of residual follicles of group B are very well differentiated that they resemble normal thyroid parenchyma, they may well be metastatic carcinomas. On the contrary, the presence of morphologically and immunohistochemically normal-looking follicles in group A, with no intrathyroid tumor, suggests that the primary PTC might possibly develop in the ectopic thyroid tissue. In cases showing morphologically and immunohistochemically normal-looking follicles in laterocervical masses, these findings might lead to a reduction of the overdiagnosis of metastatic disease of an undetected carcinoma.  相似文献   
4.
Several attempts have been made to enhance doxorubicin (DOXO) concentrations in tumour cells by drug conjugation with human albumin (HSA). HSA-DOXO has the drawback of causing DOXO accumulation in spleen and bone marrow, with a consequent leucopoenia not produced when lactose molecules are coupled to the carrier protein. In the present experiments we demonstrated that the effect of HSA lactosamination is not a consequence of a more rapid disappearance from the bloodstream of the lactosaminated conjugate (L-HSA-DOXO), which is rapidly internalized by the liver through the asialoglycoprotein receptor, but is due to a hindered uptake by spleen and bone marrow cells caused by the coupled lactose molecules. Experiments in vitro showed that HSA-DOXO produced an inhibition of murine macrophage proliferation not caused by L-HSA-DOXO. This result can be explained by higher amounts of the former conjugate entering in these cells and suggests macrophages as the cell type responsible for the spleen and bone marrow internalization of HSA-DOXO hindered by lactose coupling. Importantly, lactosamination of HSA did not reduce the marked uptake of HSA-DOXO by chemically induced rat hepatocellular carcinoma. L-HSA-DOXO, by avoiding DOXO accumulation in bone marrow is an attractive candidate for clinical trials against tumors which were found to actively internalize this conjugate in laboratory animals, such as hepatocellular carcinoma.  相似文献   
5.
6.
Summary The endoscopic insertion of self-expanding mesh stents in four patients affected by obstructing rectal malignant tumors is reported. The preliminary experience shows that, in the short term, normal defecation was achieved, with no complications. Longer follow-up is necessary to evaluate the duration and the quality of the palliative effect.  相似文献   
7.
The effects of monopolar and bipolar diathermy systems were studied in 12 male Sprague-Dawley rats. Fulguration was achieved by application of a standard current (13 W for 1 s) on the foreskin. Tissue damage was assessed by light microscopy. Results suggest that bipolar probe causes less tissue damage than its monopolar counterpart. It has proved to be of value in plastic and paediatric procedures and is recommended for the urologist's armamentarium.  相似文献   
8.
9.
10.
A case of primary malignant melanoma of the female urethra is reported. Physical examination and visceral studies confirmed the primary character of the tumour and histologic examination proved it to be nodular malignant melanoma. Less than 100 cases have been previously reported. The role of immunohistochemical stains to substantiate the diagnosis is stressed. Therapy and prognosis are briefly discussed.  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