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   1540587篇
  免费   125840篇
  国内免费   4437篇
耳鼻咽喉   25176篇
儿科学   51455篇
妇产科学   43157篇
基础医学   208456篇
口腔科学   40120篇
临床医学   142391篇
内科学   316378篇
皮肤病学   36930篇
神经病学   124331篇
特种医学   62452篇
外国民族医学   391篇
外科学   255798篇
综合类   27512篇
现状与发展   73篇
一般理论   342篇
预防医学   105195篇
眼科学   35421篇
药学   107494篇
  1篇
中国医学   2771篇
肿瘤学   85020篇
  2018年   20559篇
  2017年   17366篇
  2016年   20149篇
  2015年   21883篇
  2014年   33078篇
  2013年   42660篇
  2012年   44748篇
  2011年   46744篇
  2010年   34217篇
  2009年   36022篇
  2008年   46017篇
  2007年   47973篇
  2006年   50907篇
  2005年   47829篇
  2004年   45372篇
  2003年   43503篇
  2002年   42993篇
  2001年   65874篇
  2000年   66648篇
  1999年   57330篇
  1998年   18783篇
  1997年   16935篇
  1996年   16846篇
  1995年   15846篇
  1994年   14055篇
  1993年   12761篇
  1992年   43878篇
  1991年   43268篇
  1990年   42479篇
  1989年   41264篇
  1988年   38264篇
  1987年   37411篇
  1986年   35708篇
  1985年   33953篇
  1984年   25328篇
  1983年   21980篇
  1982年   13339篇
  1981年   11738篇
  1979年   23906篇
  1978年   16907篇
  1977年   14726篇
  1976年   13735篇
  1975年   15276篇
  1974年   17718篇
  1973年   17048篇
  1972年   16344篇
  1971年   15121篇
  1970年   14084篇
  1969年   13400篇
  1968年   12576篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
101.
Eighty-eight patients with blunt renal trauma were examined sonographically. Rupture of the kidney was diagnosed in 41 patients and contusion of the kidney in 45. The correlation between operative findings, sonography and urography showed positive sonographic findings to be correct in all patients with rupture of the kidney. In 4 patients with normal sonograms, the diagnosis of a contusion was based on the urographic results. Three patients underwent angiography. An intimal lesion was seen in 2 and a tear of the renal artery in 1. The results of our investigation suggest that sonography should be applied in the first place in the evaluation of blunt renal trauma. It is the investigation of choice during follow-up after surgical as well as conservative therapy.  相似文献   
102.
103.
Multiple trauma is often associated with blunt thoracic injuries. Especially lung contusion can result in respiratory insufficiency and therefore a higher mortality rate. In our prospective study comparing 8 multiple trauma patients with and without associated lung contusion, we found that respiratory function was already significantly disturbed (decrease of paO2/FiO2 and increase of AaDO2, a rise in extravascular lung water (EVLW) both early after trauma and also with a second peak following the 4th day. This group (LK) developed significantly more cases of respiratory distress (ARDS). The disturbance of respiratory function seen initially was interpreted as a consequence of the direct mechanical impact, leading to the formation of interstitial fluid and hematoma. The frequent development of ARDS in the LK-group probably results from a pronounced activation of cellular and humoral mechanisms and therefore an enforced injury of the pulmonary capillary bed. A significant increase of pulmonary infections or the development of sepsis was not seen in the LK-group and is probably not responsible for the higher ARDS-rate in this group.  相似文献   
104.
105.
106.
Concanavalin A-induced lymphocyte proliferation was studied in 25 patients with alcoholic hepatitis or compensated alcoholic cirrhosis. Nine alcoholics without evidence of liver disease were also evaluated. A nonlinear correlation equation, which was natural logarithmic, was applied to individual dose-response proliferation curves and permitted comparisons between patient groups and controls. The proliferative response in all patient groups was significantly lower when compared to healthy controls and was independent of the presence or absence of liver disease. This suggests that some changes in immune function observed in alcoholics may be linked to the direct effects of alcohol on the immune system rather than to the associated liver disease.  相似文献   
107.
Macrophage NRAMP1 and its role in resistance to microbial infections   总被引:12,自引:0,他引:12  
  相似文献   
108.
EDITORIAL COMMENT: We accepted this case for publication to remind readers that although uterine rupture during labour in a primigravida is extremely uncommon it does occur, or at any rate nulliparas can develop abdominal pain and shock in labour with a haemoperitoneum resulting from a tear in a vein in the lower posterior uterine wall. When one sees the hugely dilated uterine and ovarian venous plexuses at Caesarean section it is easy to believe that bleeding from such a vessel during labour could be prodigious. This case suggests that a dilated vein with blood flow derangements may be the cause. Nonetheless, as the authors warn us, the necessary response is not a precise diagnosis, but rapid laparotomy. See also Editorial Comment to Chin MMS, Harvey JA, Duffy BL. Uterine rupture during labour in a primigravida. Aust NZ J Obstet Gynaecol 1996; 36: 210.  相似文献   
109.
Membrane-bound CD14 acts as a receptor for lipopolysaccharide (LPS) on monocytes/macrophages and neutrophils. Studies have suggested that the activation of monocytes/macrophages by the binding of LPS to membrane-bound CD14 may require the association of a signal-transducing molecule with membrane-bound CD14. The observation that non-CD14 expressing cells, such as endothelial cells, can nevertheless be activated by a complex of LPS and a soluble form of CD14 (sCD14) suggests that the receptor for this complex may be identical to the signal transducing molecule associated with membrane-bound CD14. The studies described show that two CD14-specific MoAb are able to block the LPS-induced activation of endothelial cells but do not affect the response of monocytes to LPS. This suggests that the interaction of the sCD14:LPS complex with endothelial cells is distinct from the interaction of membrane-bound CD14 with its putative signal-transducing molecule.  相似文献   
110.
A 33-year-old African woman was evaluated for tender nodules on her feet. Accompanied by her four children, she had recently immigrated from Somalia. Before her immigration, she resided in a Kenyan refugee camp for approximately 1 year, where she walked barefoot in sand and dirt. The patient stated that she and her four children, as well as many people living in the same compound, had similar, tender lesions on their feet. Her children were "treated" by their grandmother, who removed the contents of their lesions with a safety pin.
On physical examination the patient had numerous tender, isolated, and clustered hyperkeratotic, crusted papules, measuring 4–6 mm, on the plantar and periungual surfaces. Several lesions were ulcerated (Figs 1 and 2). The hyperkeratotic masses were debrided with a surgical blade. An intact, white, coiled structure was curetted from each papule, leaving numerous empty crater-like lesions (Fig. 3), which were identified on histologic sections as Tunga penetrans. Microscopic examination of unstained specimens showed branching, thin, translucent tubular structures with numerous eggs. Ring-shaped cross-sections of the organism's respiratory and digestive tracts were seen on hematoxylin and eosin stain (Fig. 4).
The patient received a 10-day course of dicloxacillin and topical bacitracin ointment. All lesions were healed within 1 week of therapy.  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