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   1665297篇
  免费   119534篇
  国内免费   6409篇
耳鼻咽喉   21565篇
儿科学   50609篇
妇产科学   45103篇
基础医学   242745篇
口腔科学   46550篇
临床医学   155876篇
内科学   325796篇
皮肤病学   33698篇
神经病学   135178篇
特种医学   60393篇
外国民族医学   439篇
外科学   237857篇
综合类   36654篇
现状与发展   2篇
一般理论   511篇
预防医学   129175篇
眼科学   37303篇
药学   126060篇
  7篇
中国医学   5002篇
肿瘤学   100717篇
  2021年   13156篇
  2019年   13823篇
  2018年   19874篇
  2017年   14984篇
  2016年   16078篇
  2015年   18441篇
  2014年   25428篇
  2013年   38206篇
  2012年   52497篇
  2011年   55310篇
  2010年   32286篇
  2009年   29872篇
  2008年   50632篇
  2007年   53714篇
  2006年   53756篇
  2005年   51468篇
  2004年   49053篇
  2003年   46779篇
  2002年   45283篇
  2001年   84445篇
  2000年   86909篇
  1999年   72478篇
  1998年   19022篇
  1997年   16928篇
  1996年   16372篇
  1995年   15457篇
  1994年   14272篇
  1993年   13352篇
  1992年   55669篇
  1991年   53808篇
  1990年   51959篇
  1989年   49849篇
  1988年   45891篇
  1987年   44375篇
  1986年   42105篇
  1985年   39947篇
  1984年   29241篇
  1983年   24645篇
  1982年   14170篇
  1979年   25837篇
  1978年   17906篇
  1977年   14848篇
  1976年   13910篇
  1975年   14547篇
  1974年   17661篇
  1973年   17158篇
  1972年   16032篇
  1971年   15026篇
  1970年   13832篇
  1969年   12834篇
排序方式: 共有10000条查询结果,搜索用时 20 毫秒
81.
82.
Interferon-alpha (IFN-alpha) has proved effective in the treatment of hemangiomas, hemangioblastomas, and Kaposi's sarcoma. To investigate the ability of IFNs to inhibit angiosarcoma, we used two transformed murine endothelial cell lines that form angiosarcomas in vivo. SVR and MS1-VEGF cell lines express oncogenic H-ras or vascular endothelial growth factor (VEGF), respectively. IFN-alpha1,8, which is active against murine and human cells, inhibited SVR and MS1-VEGF proliferation in vitro by 40% at 10(3) U/mL (p = 0.028). In vivo, IFN-alpha1,8 inhibited SVR tumor volume by 71% (p = 0.047) and MS1-VEGF volume by 79% (p = 0.003). Tumor-induced angiogenesis was decreased in SVR tumors by 52% (p = 0.005) and in MS1-VEGF tumors by 58% (p = 0.001). Sera from IFN-alpha1,8-treated mice bearing either SVR or MS1-VEGF tumors demonstrated a 5-fold increase in IP-10/CXCL10 (p = 0.001), an IFN-induced antiangiogenic protein. Both recombinant IP-10 and IFN-alpha1,8 inhibited human umbilical vein endothelial cell (HUVEC) vessel formation in the fibrin gel assay, a three-dimensional culture model of angiogenesis, by 56% at 25 ng/mL and 50% at 1.2 ng/mL, respectively (p < 0.001). An IP-10 blocking antibody restored vessel formation to 80% of untreated controls (p = 0.001). Given the magnitude of the in vivo response, these data suggested that the antitumor effects of IFN-alpha1,8 were likely mediated through angiogenesis inhibition rather than solely by direct inhibition of tumor cell proliferation.  相似文献   
83.
Relationship-centered care reflects both knowing and feeling: the knowledge that physician and patient bring from their respective domains of expertise, and the physician’s and patient’s experience, expression, and perception of emotions during the medical encounter. These processes are conveyed and reciprocated in the care process through verbal and nonverbal communication. We suggest that the emotional context of care is especially related to nonverbal communication and that emotion-related communication skills, including sending and receiving nonverbal messages and emotional self-awareness, are critical elements of high-quality care. Although nonverbal behavior has received far less study than other care processes, the current review argues that it holds significance for the therapeutic relationship and influences important outcomes including satisfaction, adherence, and clinical outcomes of care.  相似文献   
84.
A 19-item survey instrument was designed and mailed by the Infectious Diseases Society of America to its membership to determine the media preferred by infectious diseases physicians for continuing medical education on general topics and on antimicrobial resistance. The objective of the survey was to offer the developers of educational programs knowledge on which to base more-effective ways to deliver educational materials to physicians in this specialty.  相似文献   
85.
Knowing Ron     
Spechko  Phyllis L. 《JAMA》2006,296(7):738
  相似文献   
86.
87.
88.
BACKGROUND: Arterial hypertension and postmenopausal reduction of estrogen levels may be involved in modifications of the stiffness of large arteries. OBJECTIVES: To evaluate the pulse-wave velocity (PWV) and indirectly the arterial stiffness in hypertensive postmenopausal women submitted to hormone therapy with estradiol alone or combined with norethisterone acetate. SUBJECTS: Forty-five hypertensive postmenopausal women were double-blindly, randomly assigned to three arms of treatment: placebo (group I); estradiol 2 mg/day (group II); or estradiol 2 mg/day and norethisterone acetate 1 mg/day (group III). METHODS: Arterial stiffness was assessed from PWV measurements of the common carotid and femoral arteries (CF-PWV) and the common carotid and radial arteries (CR-PWV) obtained using the automatic Complior(R) device, taken at baseline and after 12 weeks of treatment. RESULTS: After the 12-week treatment, values of CF-PWV and CR-PWV were not significantly different (p = 0.910 and p = 0.736, respectively) among the groups. Systolic blood pressure showed a positive correlation with CF-PWV in groups II and III (p = 0.02 and p < 0.001, respectively). CONCLUSIONS: PWV and arterial stiffness in postmenopausal hypertensive women did not reduce over a 12-week treatment with estradiol alone compared with the same period of treatment with estradiol combined with norethisterone acetate.  相似文献   
89.
90.
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