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   9896篇
  免费   460篇
  国内免费   70篇
耳鼻咽喉   85篇
儿科学   182篇
妇产科学   169篇
基础医学   1248篇
口腔科学   174篇
临床医学   655篇
内科学   2418篇
皮肤病学   144篇
神经病学   812篇
特种医学   385篇
外科学   2060篇
综合类   30篇
现状与发展   1篇
预防医学   186篇
眼科学   117篇
药学   596篇
中国医学   8篇
肿瘤学   1156篇
  2023年   66篇
  2022年   114篇
  2021年   208篇
  2020年   129篇
  2019年   169篇
  2018年   199篇
  2017年   179篇
  2016年   245篇
  2015年   242篇
  2014年   304篇
  2013年   359篇
  2012年   569篇
  2011年   612篇
  2010年   397篇
  2009年   355篇
  2008年   599篇
  2007年   647篇
  2006年   632篇
  2005年   645篇
  2004年   673篇
  2003年   616篇
  2002年   577篇
  2001年   121篇
  2000年   117篇
  1999年   142篇
  1998年   137篇
  1997年   120篇
  1996年   128篇
  1995年   87篇
  1994年   88篇
  1993年   74篇
  1992年   99篇
  1991年   73篇
  1990年   76篇
  1989年   56篇
  1988年   67篇
  1987年   62篇
  1986年   72篇
  1985年   41篇
  1984年   41篇
  1983年   26篇
  1982年   23篇
  1981年   17篇
  1980年   15篇
  1979年   30篇
  1978年   27篇
  1977年   15篇
  1976年   20篇
  1970年   13篇
  1969年   17篇
排序方式: 共有10000条查询结果,搜索用时 359 毫秒
31.
Off-pump coronary artery bypass grafting has become an attractive surgical alternative for myocar-dial revascularization because of the advantage of myocardial protection and other benefits of patients. However, it is still regarded as a controversial treatment for the coronary artery disease accompanied by atrial fibrillation (AF). A significant number of patients in need of coronary revascularization have chronic AF. Although the Cox-Maze III procedure is the gold standard for the surgical treatment of AF, few of these patients undergo AF operations at the time of their coronary bypass grafting. We report herein a case of the pulmonary vein isolation to eliminate the AF by means of epicardial radiofrequency ablation combined with 2 vessels coronary artery bypass grafting on the beating heart with the aid of cardiopulmonary bypass.  相似文献   
32.
33.
34.
Although the causes of stroke are diverse, thromboembolism due to a mobile aortic thrombus is rare. We describe a surgical case of acute massive pulmonary embolism after critical cerebral infarction associated with a mobile ascending aortic thrombus in a 52-year-old woman. Concomitant surgical removal of the aortic thrombus and pulmonary embolectomy was performed successfully, and the patient has been stable without recurrent thromboembolic complications after 18 months of follow-up.  相似文献   
35.
This study evaluated the usefulness of midazolam in inducing a anesthetic state in 60 patients who underwent surgery under general anesthesia. The patients were divided into 3 groups; a geriatric group, a hepatic dysfunction group, and a control group (adults without complications). To induce sleep 0.15 mg.kg-1 or 0.2 mg.kg-1 of midazolam was administered intravenously to all three groups. After the administration of midazolam, the mean time for obtaining absence of response to calling name and absence of ciliary reflex were not significantly different in the three groups. The pulse rate and respiratory rate also did not change remarkably. But significant decreases were observed in the systolic blood pressure and tidal volume in all three groups. However, they were not significantly different among the three groups. These results indicate that midazolam is a useful drug for inducing anesthetic state in geriatric patients and patients with hepatic dysfunction.  相似文献   
36.
A human chromosomal translocation t(8;9) was detected using two-color fluorescence in situ hybridization with probes capable of staining the entire lengths of each of these chromosomes. The chromosome 8 probe was labeled with biotin and detected with Texas red, while the chromosome 9 probe was labeled with AAF and detected with FITC . In normal metaphase spreads, two metaphases from the proband, two red, one green and one part red and part green derivative chromosome were seen. The bicolor chromosome corresponded to translocation of a chromosome 8 segment to the distal part of the q region of one chromosome 9, as originally indicated by banding analysis. In interphase nuclei of the proband, four domains with bright fluorescence were recognized in many nuclei. Two were red, one was green, and the fourth had portions of both colors, indicating the presence of the translocation.  相似文献   
37.
Occipital horn syndrome: report of a patient and review of the literature   总被引:1,自引:0,他引:1  
We report an 18-year-old boy with occipital horn syndrome and we review the 20 cases previously published with this syndrome. The distinctive features common to all patients were unusual facial appearance, skeletal abnormalities, chronic diarrhea and genitourinary abnormalities. The skeletal abnormalities included occipital horns, short, broad clavicles, deformed radii, ulnae, and humeri, narrowing of the rib cage, undercalci-fied long bones with thin cortical walls and coxa valga. Occipital horn syndrome is inherited in an X-linked recessive fashion. Our analysis indicates that occipital horn syndrome is associated with a recognizable characteristic phenotype.  相似文献   
38.
Pyoderma gangrenosum is a rare, chronic, inflammatory ulcerative skin disease of unknown etiology and pathogenesis. It is often associated with systemic disease. We describe a patient with pyoderma gangrenosum associated with ulcerative colitis and aseptic abscesses of the subcutis and spleen, which have been rarely reported previously. These manifestations were cleared by combined therapy with minocycline hydrochloride and diaphenylsulfone.  相似文献   
39.
p = 0.0007) and tumor necrosis (TN) (HMC: p = 0.0050). Univariate analysis showed that AMC or HMC was a statistically significant predictor of overall survival in all patients ( p = 0.0086 and p = 0.0307, respectively). Multivariate analysis showed that AMC was an independent predictor of node status when we fitted a model with node status, BVI, and either AMC or HMC; but HMC was not independent. However, when we fitted a model including all 11 of the other indicators and AMC or HMC, the node status, HG, and LI were independent predictors, but AMC and HMC were not. Although AMC was a better method than HMC for evaluating angiogenesis, we cannot confirm angiogenesis as a significant independent prognostic factor associated with long-term survival in Japanese breast cancer patients.  相似文献   
40.
Summary: Transforming growth factor-α (TGF-α) and epidermal growth factor (EGF) are structurally related mitogenic polypeptides. They share the same receptor; EGF receptor. the EGF receptor is widely expressed in human fetal tissues including the kidney, but little is known about the role of TGF-α/EGF/EGF receptor system in human fetal kidney. the expression of TGF-α, EGF and their common receptor was investigated immunohistochemically in the human fetal kidneys. In the cortex, immunoreactivity for TGF-α was found in the differentiating proximal tubules. In contrast, immunoreactivity for EGF was present in the thick ascending limbs of the Henle's loop (TAL) and medullary collecting duct cells (CD). Immunoreactivity for their common receptor was present mainly in the TAL and medullary CD. These data support the assumption that the system of TGF-α, EGF and its receptor has an important role in the proliferation and differentiation of the TAL and medullary CD. the different localization of TGF-α and its receptor may indicate that TGF-α acts through a paracrine mechanism. the co-localization of EGF and its receptor in the TAL and medullary CD suggests that EGF may act as an autocrine growth factor.  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