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   936445篇
  免费   66769篇
  国内免费   1380篇
耳鼻咽喉   13009篇
儿科学   24478篇
妇产科学   23373篇
基础医学   133493篇
口腔科学   28299篇
临床医学   80930篇
内科学   184341篇
皮肤病学   19295篇
神经病学   72543篇
特种医学   36968篇
外国民族医学   79篇
外科学   152769篇
综合类   18138篇
现状与发展   1篇
一般理论   237篇
预防医学   62009篇
眼科学   21470篇
药学   72830篇
  3篇
中国医学   2184篇
肿瘤学   58145篇
  2018年   9124篇
  2017年   7151篇
  2016年   7895篇
  2015年   9037篇
  2014年   12187篇
  2013年   17729篇
  2012年   24430篇
  2011年   25364篇
  2010年   14994篇
  2009年   14437篇
  2008年   24853篇
  2007年   25935篇
  2006年   26720篇
  2005年   25639篇
  2004年   24761篇
  2003年   23792篇
  2002年   23305篇
  2001年   54818篇
  2000年   56636篇
  1999年   47018篇
  1998年   10768篇
  1997年   9492篇
  1996年   9615篇
  1995年   8944篇
  1994年   8297篇
  1993年   7613篇
  1992年   35539篇
  1991年   33961篇
  1990年   32793篇
  1989年   31908篇
  1988年   29027篇
  1987年   28294篇
  1986年   26314篇
  1985年   25185篇
  1984年   17864篇
  1983年   15160篇
  1982年   7811篇
  1981年   6787篇
  1979年   15794篇
  1978年   10612篇
  1977年   9064篇
  1976年   7883篇
  1975年   8636篇
  1974年   10475篇
  1973年   9866篇
  1972年   9359篇
  1971年   8856篇
  1970年   8429篇
  1969年   7926篇
  1968年   7204篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
The results of diagnosis and treatment of iatrogenic injuries of the extrahepatic biliary tract in 47 patients are analysed. The injury was detected during the operation only in 6 cases, in 41 cases it was revealed on the 1st-6th postoperative day. Intensive conservative therapy was applied in the preoperative period to correct the values of homeostasis and metabolism. Special attention was attached to antibacterial therapy aimed at suppression of ++non-clostridial anaerobic infection. Sixty-three surgical interventions were conducted on 47 patients; 47 of them were restorative or reconstructive, 15 were undertaken for emergency indications, one, for developed postoperative complication. One patient died. Particular importance was attached to adequate draining both in emergency and in reconstructive and restorative operations.  相似文献   
992.
993.
994.
The results of resection of the liver in repeated operations on patients with parasitic disease of the liver are discussed. Operations were conducted on 22 patients with alveococcosis and 7 patients with echinococcosis. By means of the method of atypical liver resection radical operations were performed on 20 patients (69%) and palliative resections of the liver in 9 patients (31%). The palliative resections were combined with cryodestruction of the remaining parasitic tissue, which improved the therapeutic effect significantly and prolonged the patients' survival. The volume of the resection ranged from a segment to one half of the liver. The fatality rate was 6.8%.  相似文献   
995.
Summary NPY is a putative neurotransmitter mainly co-localized with noradrenaline in sympathetic fibers which innervate the cerebral vasculature. The origin of most of the perivascular NPY fibers seems to be in the superior cervical ganglion. To investigate involvement of Neuropeptide Y (NPY) mechanisms in subarachnoid haemorrhage (SAH), twenty patients with SAH were investigated. NPY-LI (-like immunoreactivity) levels in the external jugular vein were assessed using radioimmunoassay in blood samples collected postoperatively (or after SAH in non-surgical patients) on days 1, 2, 3, 5, 7 and 9. These levels were compared with the clinical course and blood flow velocity changes monitored with ultrasonic Doppler equipment from both middle cerebral arteries (MCA) and both internal carotid arteries (ICA).Compared to NPY-LI levels in 14 controls (mean 116±3 pmol/ l), increased levels (up to 253 pmol/l) and a close relationship between velocities and NPY-LI levels were found in a subpopulation of the SAH patients. When comparing the mean haemodynamic index (V MCA/ipsilateral V ICA) and mean NPY-LI levels in each of the 20 patients, a correlation of r=0.75, p=0.0001 was found. Increased NPY-LI were found (131±8 pmol/l) when simultaneous Doppler velocity recordings showed vasoconstriction (Haemodynamic index >5) compared with samples taken when the haemodynamic index was <5, p<0.05. When MCA velocity exceeded 120 cm/sec, increased levels were found (129±9 pmol/l) compared with the conditions when MCA velocity was less than 120 cm/sec (113±5 pmol/ l), p=0.06. The results indicate a possible NPY involvement in cerebral vasoconstriction after SAH.  相似文献   
996.
Antigenic characterization of urothelial cells cultured from normal adult ureter was performed. These cells were cultured using a simplified isolation and culture technique and a commercially available serum-free medium. The cells growing in these cultures had epithelioid morphology and normal quantities of DNA. The antigen expression on these cultured normal urothelial cells was evaluated using a panel of monoclonal antibodies: 5G6.4, AN43, URO-5, anti-keratin and anti-blood group antibodies, and 425 (anti-epidermal growth factor receptor). Lower levels of anti-A and AN43 binding on cultured cells were observed than are seen on urothelial cells in sections of normal ureter, while the binding of anti-blood group H, 5G6.4, and URO-5 was unchanged. Binding of anti-epidermal growth factor receptor antibody 425 was improved if the cells were grown in medium lacking epidermal growth factor. These results confirm the urothelial origin of these cultured urothelial cells but indicate that some antigenic differences between cultured normal urothelial cells and urothelial cells in situ in the normal ureter exist.  相似文献   
997.
The authors describe two surgically cured cases of symptomatic subependymomas located in the lateral ventricle and septum pellucidum with emphasis on magnetic resonance imaging study. Both computed tomography and MRI revealed a calcified mass with repeated intratumoral hemorrhages. Cerebral angiograms disclosed rather hypovascular lesions. The histologic diagnosis was proven to be of subependymoma. The pertinent literature of surgically treated subependymomas is reviewed, and the characteristic biologic features are also discussed.  相似文献   
998.
Assay of FK 506 in plasma.   总被引:1,自引:0,他引:1  
  相似文献   
999.
1000.
Although the cause varies widely, we recently experienced a case of constrictive pericarditis of which cause seemed to be traumatic as described below. The patient was a 62-year-old man having a history of epigastric trauma about 20 years ago. Since then, palpitation appeared and he was recently hospitalized in our department for the purpose of receiving an operation under the diagnosis of constrictive pericarditis. At operation, a hematoma was found in the pericardial region, which was considered to have been caused by trauma in the past. Less reports have so far been available concerning trauma-induced constrictive pericarditis and this case thus seemed to be of rarity as well.  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