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   162724篇
  免费   6676篇
  国内免费   345篇
耳鼻咽喉   2192篇
儿科学   4723篇
妇产科学   3778篇
基础医学   23447篇
口腔科学   5374篇
临床医学   9227篇
内科学   35968篇
皮肤病学   4448篇
神经病学   13128篇
特种医学   3983篇
外国民族医学   1篇
外科学   18813篇
综合类   765篇
一般理论   24篇
预防医学   19600篇
眼科学   4314篇
药学   12758篇
中国医学   658篇
肿瘤学   6544篇
  2023年   814篇
  2021年   2420篇
  2020年   1359篇
  2019年   2796篇
  2018年   4940篇
  2017年   3072篇
  2016年   3052篇
  2015年   3399篇
  2014年   3708篇
  2013年   5711篇
  2012年   10002篇
  2011年   10563篇
  2010年   5184篇
  2009年   3753篇
  2008年   8650篇
  2007年   9308篇
  2006年   8929篇
  2005年   8541篇
  2004年   7920篇
  2003年   7434篇
  2002年   7062篇
  2001年   4864篇
  2000年   5447篇
  1999年   4134篇
  1998年   699篇
  1992年   2214篇
  1991年   1986篇
  1990年   1972篇
  1989年   1678篇
  1988年   1602篇
  1987年   1502篇
  1986年   1541篇
  1985年   1449篇
  1984年   1035篇
  1983年   891篇
  1979年   1205篇
  1978年   804篇
  1977年   779篇
  1976年   741篇
  1975年   875篇
  1974年   1119篇
  1973年   1164篇
  1972年   1110篇
  1971年   1076篇
  1970年   1006篇
  1969年   1082篇
  1968年   1105篇
  1967年   977篇
  1966年   878篇
  1965年   548篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
111.
Normal seminal vesicles were studied histologically in 80, and by Feulgen’s cytophotometric method in 10 autopsied cases (males, 44–82 years of age). In every case large, hyperchromatic nuclei were found. By cytophotometry euploid polyploid atypia was also shown in every case, which is characteristic of benign hormonal dysplasia.  相似文献   
112.
A retrospective study was done in 316 patients with primary cervical adenocarcinoma treated at the Research Institute for Clinical and Experimental Oncology in Brno over a period of 40 years (1939-1978). The treatment results were compared to those in 2571 patients with epidermoid carcinomas of the uterine cervix treated at the Institute over the same period. The 5-year survival rate was significantly lower in adenocarcinoma patients (in Stage I patients, 77.8% vs. 84.5%, and, in the whole group, 60.8% vs. 70.3%). The assessment of the treatment results of this study has clearly showed that in cervical adenocarcinomas, surgery combined with radiotherapy was much more effective than radical radiotherapy alone (77.4% vs. 64.7%). In contrast to this, in epidermoid carcinomas the treatment results were better after radical radiotherapy (86.5% vs. 81.3%). Thus, in the prognosis of cervical adenocarcinomas the mass of the tumor, the size of the uterus, as well as the grading play a role. That means that primary cervical adenocarcinomas at early stages can be successfully treated by a combination of radical surgery and radiotherapy, while radiotherapy of advanced stages of this tumor is less successful.  相似文献   
113.
Compromise of immune function in obstructive jaundice.   总被引:5,自引:0,他引:5  
  相似文献   
114.
Intracerebroventricular (ICV) microinfusion of recombinant human interleukin-1 beta (rhIL-1 beta, 0.125 to 2.0 ng/rat) dose-dependently suppressed 2 h and nighttime food intake in rats. The following daytime food intake did not change or increased. ICV infusion of bovine serum albumin (BSA), or heat-treated rhIL-1 beta had no effect on food intake. Pretreatment with dexamethasone (200 micrograms/rat, intraperitoneal) blocked the food intake suppression induced by low doses of rhIL-1 beta. This ability of dexamethasone, a synthetic corticosteroid, may have potential therapeutic implications in acute and chronic pathological processes associated with increased levels of IL-1 and appetite suppression.  相似文献   
115.
Occupation and bladder cancer in Spain: a multi-centre case-control study   总被引:5,自引:0,他引:5  
A case-control study on bladder cancer was carried out in four regions of Spain. The study included 497 cases (438 males and 59 females), 583 hospital controls and 530 population controls matched by sex, age and residence. The present paper reports the results of the analyses on occupational history. Among men, an increased risk of bladder cancer was found for textile workers (OR = 1.97, 95% CL 1.2-3.3), mechanics and maintenance workers (OR = 1.86, 95% CL 1.2-2.8), workers in the printing industry (OR = 2.06, 95% CL 1.0-4.3) and for managers (OR = 2.03, 95% CL 1.2-3.5). The risk was highest among those first employed in the textile industry before the age of 25 and prior to 1960. Among mechanics the risk was highest for those who started after the age of 25 and later than 1960. The OR for smokers who had also been employed in one of the high risk occupations was 7.82 (95% CL 4.4-14.0) which is compatible with a multiplicative effect of joint exposure to tobacco and occupational hazards.  相似文献   
116.

Background  

Mycoplasma fermentans has been associated with rheumatoid arthritis. Recently, it was detected in the joints and blood of patients with rheumatoid arthritis, but it is not clear yet how the bacteria enter the body and reach the joints. The purpose of this study was to determine the ability of M. fermentans to induce experimental arthritis in rabbits following inoculation of the bacteria in the trachea and knee joints.  相似文献   
117.
Immunoregulators in the nervous system   总被引:15,自引:0,他引:15  
The nervous system, through the production of neuroregulators (neurotransmitters, neuromodulators and neuropeptides) can regulate specific immune system functions, while the immune system, through the production of immunoregulators (immunomodulators and immunopeptides) can regulate specific nervous system functions. This indicates a reciprocal communication between the nervous and immune systems. The presence of immunoregulators in the brain and cerebrospinal fluid is the result of local synthesis--by intrinsic and blood-derived macrophages, activated T-lymphocytes that cross the blood-brain barrier, endothelial cells of the cerebrovasculature, microglia, astrocytes, and neuronal components--and/or uptake from the peripheral blood through the blood-brain barrier (in specific cases) and circumventricular organs. Acute and chronic pathological processes (infection, inflammation, immunological reactions, malignancy, necrosis) stimulate the synthesis and release of immunoregulators in various cell systems. These immunoregulators have pivotal roles in the coordination of the host defense mechanisms and repair, and induce a series of immunological, endocrinological, metabolical and neurological responses. This review summarizes studies concerning immunoregulators--such as interleukins, tumor necrosis factor, interferons, transforming growth factors, thymic peptides, tuftsin, platelet activating factor, neuro-immunoregulators--in the nervous system. It also describes the monitoring of immunoregulators by the central nervous system (CNS) as part of the regulatory factors that induce neurological manifestations (e.g., fever, somnolence, appetite suppression, neuroendocrine alterations) frequently accompanying acute and chronic pathological processes.  相似文献   
118.
Synaptic contacts between growth hormone-releasing hormone (GHRH)- and somatostatin-containing neurons were demonstrated in the rat hypothalamus by a double-staining immunocytochemical method at the electron microscopic level. Somatostatin-immunoreactive nerve terminals synapse on GHRH-positive dendrites and cell bodies in the arcuate nucleus. A fine network of GHRH-immunopositive nerve terminals was observed at the light microscopic level in the rostral part of the periventricular nucleus and in the dorsal part of the arcuate nucleus around somatostatin-containing neuronal elements. With the electron microscope synaptic contact between GHRH-containing nerve terminals and somatostatin-containing dendrites are demonstrated. The reciprocal innervation between GHRH- and somatostatin-containing neurons that project to the median eminence and regulate growth hormone secretion must allow them to coordinate their activities.  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