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   53192篇
  免费   3426篇
  国内免费   156篇
耳鼻咽喉   737篇
儿科学   1495篇
妇产科学   891篇
基础医学   6331篇
口腔科学   925篇
临床医学   5426篇
内科学   11349篇
皮肤病学   894篇
神经病学   4988篇
特种医学   2054篇
外国民族医学   1篇
外科学   9090篇
综合类   579篇
一般理论   49篇
预防医学   3596篇
眼科学   867篇
药学   3334篇
中国医学   54篇
肿瘤学   4114篇
  2023年   273篇
  2022年   435篇
  2021年   1138篇
  2020年   664篇
  2019年   1152篇
  2018年   1357篇
  2017年   993篇
  2016年   1039篇
  2015年   1223篇
  2014年   1878篇
  2013年   2432篇
  2012年   3900篇
  2011年   4069篇
  2010年   2257篇
  2009年   1942篇
  2008年   3535篇
  2007年   3700篇
  2006年   3736篇
  2005年   3622篇
  2004年   3485篇
  2003年   3217篇
  2002年   3006篇
  2001年   513篇
  2000年   398篇
  1999年   506篇
  1998年   608篇
  1997年   492篇
  1996年   375篇
  1995年   371篇
  1994年   342篇
  1993年   287篇
  1992年   286篇
  1991年   285篇
  1990年   266篇
  1989年   236篇
  1988年   238篇
  1987年   211篇
  1986年   197篇
  1985年   205篇
  1984年   222篇
  1983年   212篇
  1982年   221篇
  1981年   198篇
  1980年   146篇
  1979年   132篇
  1978年   122篇
  1977年   93篇
  1976年   61篇
  1974年   76篇
  1973年   59篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
51.
To date, there is no clinicopathological correlation of adrenal medullary transplant cases in patients with survival beyond a few years. Postmortem examination of a brain from a patient with Parkinson's disease (PD), 16 years after autologous adrenal medullary transplant, was performed using tyrosine hydroxylase (TH) and chromogranin A. The patient experienced a four-year initial improvement in motor function followed by resumption of the progressive nature of her disease that continued until her death. She expired 16 years following grafting. At autopsy, TH stain of the brain revealed severe loss of TH-immunoreactivity in the substantia nigra and Lewy bodies, confirming the diagnosis of PD. The transplant site was identified by the presence of scarring and there was complete absence of any TH staining cells at the site of the transplant. There were few surviving cells staining with chromogranin A. The absence of TH-staining cells in the transplant 16 years after surgery provides further evidence that adrenal medullary transplants do not survive in the long term.  相似文献   
52.
Alfier  Jeffrey C. 《JAMA》2004,292(11):1275
  相似文献   
53.
54.
55.
Six hundred patients were prospectively randomized and given either diatrizoate meglumine 60 or iohexol 300 during dynamic contrast-enhanced body CT in order to compare image quality, contrast reactions, and the number of aborted studies or studies in which images had to be repeated. Three hundred two patients received iohexol 300, and 298 patients received diatrizoate meglumine 60. Thirty-nine percent (119/302) of the patients given iohexol 300 and 63% (188/298) of the patients given diatrizoate meglumine 60 had at least one adverse reaction thought to be related to contrast material during, or within 24 hr of, the body CT scan. When reactions of discomfort (heat or warmth, flushing, bad taste) were excluded, 16% (48/302) of the patients who received iohexol and 33% (99/298) of the patients who were given diatrizoate meglumine 60 had at least one adverse reaction. The differences in both types of reactions between the two agents were significant (p less than .001). Among scans evaluated for study quality, 71% (214/302) of the iohexol 300 group and 62% (184/298) of the diatrizoate meglumine 60 group had optimal enhancement (p = .02). However, when the optimal and adequate categories were combined, 301 of 302 patients given iohexol 300 and 292 of 298 patients given diatrizoate meglumine 60 had diagnostic-quality studies (no statistical difference). Studies were not terminated nor were images repeated in 97% (292/302) of the patients given iohexol 300 and in 94% (280/298) of those given diatrizoate meglumine 60. The CT study was repeated because of movement during the contrast injection or aborted because of contrast-related reactions in 0.7% of the patients given iohexol 300 and in 3.0% of the patients given diatrizoate meglumine 60. This difference was statistically significant (p = .04). Our results suggest that the difference in image quality, number of adverse reactions, and number of aborted/repeated CT scans performed with iohexol 300 or diatrizoate meglumine 60 are not sufficiently different to warrant conversion to nonionic agents for body CT scans.  相似文献   
56.
Immunohistochemical expression of carbonic anhydrase isoenzyme II (CAII) was demonstrated in a population of fibrous astrocytes in a young lamb and an adult sheep. Such cells were identified by co-expression of CAII and glial fibrillary acidic protein, nuclear morphology and their contribution of glial fibrillary acidic protein reactive processes to the glial limitans. Similar cells were not identified in neonatal lambs. As in man and mouse, CAII was also expressed in choroid plexus epithelium occurring in neonate, young and adult sheep brain. In contrast, however, to man and mouse, CAII was not expressed in sheep oligodendrocytes.  相似文献   
57.
Book Review     
Paediatric Forensic Medicine and Pathology Edited by J. K. Mason London: Chapman and Hall Medical [Published in United States by Van Nostrand Reinhold9.95. New York], 1989, xii + 516 pp, $13  相似文献   
58.
The information needs of women newly diagnosed with breast cancer   总被引:4,自引:0,他引:4  
Nurses can play a key role in patient education, including providing patients with useful and approrate information Rather than focusing on the process of education or information giving by nurses, this study places emphasis on the content of that information by taking the patients'perspective and asking the patients themselves what particular types of information are perceived as important at a specific point in time The aim of the study was to explore what particular types of information were important to women newly diagnosed with breast cancer, to enable nurses and other health care professionals to utilize their time as effectively as possible and provide a high-quality service to individuals in their care Women with breast cancer (a mean of 2 5 weeks from diagnosis) were interviewed and asked to compare items of information The items of information were presented m pairs and the women stated a preference for one item in that pan- Thirty-six pairs were presented in total The analysis involved the use of a Thurstone scaling model, which allowed rank ordermgs, or profiles of information needs, to be developed, reflecting the perceived importance of each item Information about the likelihood of cure, the spread of the disease and treatment options were perceived as the most important items of information at the tune of diagnosis Other information needs, in order of descending priority, included information about the risk to family, side-effects  相似文献   
59.
60.
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