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   11255篇
  免费   1152篇
  国内免费   38篇
耳鼻咽喉   90篇
儿科学   438篇
妇产科学   217篇
基础医学   1411篇
口腔科学   336篇
临床医学   1272篇
内科学   2060篇
皮肤病学   153篇
神经病学   1049篇
特种医学   441篇
外科学   1741篇
综合类   382篇
一般理论   30篇
预防医学   972篇
眼科学   177篇
药学   912篇
中国医学   4篇
肿瘤学   760篇
  2021年   123篇
  2020年   96篇
  2019年   138篇
  2018年   165篇
  2017年   122篇
  2016年   120篇
  2015年   141篇
  2014年   258篇
  2013年   361篇
  2012年   440篇
  2011年   450篇
  2010年   273篇
  2009年   291篇
  2008年   453篇
  2007年   525篇
  2006年   473篇
  2005年   507篇
  2004年   462篇
  2003年   418篇
  2002年   382篇
  2001年   422篇
  2000年   371篇
  1999年   354篇
  1998年   169篇
  1997年   132篇
  1996年   140篇
  1995年   136篇
  1994年   111篇
  1993年   126篇
  1992年   295篇
  1991年   269篇
  1990年   275篇
  1989年   263篇
  1988年   262篇
  1987年   265篇
  1986年   250篇
  1985年   241篇
  1984年   178篇
  1983年   152篇
  1982年   140篇
  1981年   106篇
  1980年   89篇
  1979年   119篇
  1978年   91篇
  1977年   78篇
  1976年   103篇
  1975年   91篇
  1974年   95篇
  1973年   117篇
  1972年   96篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
71.
72.
73.
OBJECTIVE: Sentinel lymph node (SLN) biopsy is an integral part of the surgical management of patients with breast cancer. Rapid immunohistochemistry (RIHC) has the potential to increase detection of metastatic carcinoma at the time of frozen section consultation. The authors assessed the accuracy and turnaround time of a newly developed RIHC method for pancytokeratin (RIHC-CK). METHODS: Sixty-six SLNs from 32 patients with breast carcinoma were examined for metastasis using the Zymed Sentinel Lymph Node Rapid IHC Kit. Intraoperative frozen sections (6 mum) of the SLNs were incubated with Zymed anti-pan-cytokeratin/HRP conjugate, diaminobenzidine (DAB), and stained with hematoxylin. Slides were ready within 8 minutes and were interpreted as positive or negative for metastatic carcinoma. Results were compared with previous intraoperative touch preparations, frozen sections, hematoxylin and eosin (Perm H&E), and AEl/3-immunostained permanent sections (Perm CK). RESULTS: Fourteen lymph nodes (19%) in 13 patients tested positive for metastatic carcinoma in Perm H&E, the gold standard. RIHC-CK had the highest sensitivity (92%) of the intraoperative tests, compared with touch preparations (64%) and frozen sections (80%). RIHC-CK showed 94% accuracy, compared with 96% (frozen section) and 93% (touch preparation). The RIHC technique took 8 minutes and was easy to perform and interpret. CONCLUSIONS: Zymed RIHC is a sensitive method for detecting breast cancer metastases in SLNs. The speed, accuracy, and ease of interpretation of the test allow for recognition of micrometastases (<2 mm) that might otherwise be undetectable by current methods of intraoperative evaluation. The prognostic significance and effect on surgical management of micrometastases in SLNs have yet to be determined.  相似文献   
74.
75.
The effects of microiontophoretic ejection of tizanidine were compared with those of adrenoceptor agonists on responses of single laminae IV and V neurones to noxious and innocuous cutaneous stimuli. Tizanidine, noradrenaline and clonidine depressed neuronal responses to noxious but not innocuous stimuli. Spontaneous activity was also depressed by these three substances. By contrast, beta- and alpha 1-adrenoceptor agonists had no consistent effect on neuronal responses to cutaneous stimuli. The selective actions of tizanidine, noradrenaline and clonidine were reversibly antagonized by the alpha 2-adrenoceptor antagonist RX781094 but not by WB4101 (alpha 1 antagonist). The binding of an alpha 2-adrenoceptor ligand to rat brain membranes was preferentially displaced by tizanidine. These results indicate an interaction of tizanidine with central alpha 2-adrenoceptors.  相似文献   
76.
Two cases of angiokeratoma corporis diffusum with mental retardation and some features of a mucopolysaccharidosis have been investigated biochemically, histopathologically, and by electron microscopy. It is submitted, on this evidence, that they are examples of a hitherto undescribed form of lysosomal enzyme deficiency disease.  相似文献   
77.
Baclofen reduced the frequency and aborted the bursts of spontaneous paroxysmal discharges in rat neocortical slices maintained in magnesium-free medium. This action was prevented by pretreatment with barium or caesium, which each increased the ictaform burst frequency, amplitude and duration. 4-Amino-pyridine also increased the burst frequency but reduced the amplitude and did not completely prevent the action of baclofen. Evidently baclofen suppresses such discharges by opening potassium channels normally involved in limiting the burst activity.  相似文献   
78.
Huntington's disease (HD) is a dominant disorder characterized by premature and progressive neurodegeneration. In order to generate an accurate model of the disease, we introduced an HD-like mutation (an extended stretch of 72-80 CAG repeats) into the endogenous mouse Hdh gene. Analysis of the mutation in vivo reveals significant levels of germline instability, with expansions, contractions and sex-of-origin effects in evidence. Mice expressing full-length mutant protein display abnormal social behaviour in the absence of acute neurodegeneration. Given that psychiatric changes, including irritability and aggression, are common findings in HD patients, our data are consistent with the hypothesis that some clinical features of HD may be caused by pathological processes that precede gross neuronal cell death. This implies that effective treatment of HD may require an understanding and amelioration of these dysfunctional processes, rather than simply preventing the premature death of neurons in the brain. These mice should facilitate the investigation of the molecular mechanisms that underpin the pathway from genotype to phenotype in HD.  相似文献   
79.
Johnson et al [1983] reported on a large family with alopecia-anosmia-deafness-hypogonadism syndrome. We report the detailed findings of an unrelated, affected individual and emphasize the presence of hypohidrosis in our case. Our case indicates that this syndrome is not a private syndrome.  相似文献   
80.
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