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   2349903篇
  免费   171615篇
  国内免费   3331篇
耳鼻咽喉   32049篇
儿科学   75897篇
妇产科学   62689篇
基础医学   348211篇
口腔科学   63633篇
临床医学   211348篇
内科学   457287篇
皮肤病学   51727篇
神经病学   185290篇
特种医学   88010篇
外国民族医学   489篇
外科学   353863篇
综合类   47510篇
现状与发展   12篇
一般理论   848篇
预防医学   182732篇
眼科学   54330篇
药学   175127篇
  11篇
中国医学   4575篇
肿瘤学   129211篇
  2021年   18981篇
  2019年   19538篇
  2018年   27062篇
  2017年   20358篇
  2016年   22746篇
  2015年   25638篇
  2014年   36095篇
  2013年   53955篇
  2012年   74676篇
  2011年   79408篇
  2010年   47057篇
  2009年   44566篇
  2008年   74609篇
  2007年   79479篇
  2006年   80296篇
  2005年   77782篇
  2004年   74367篇
  2003年   71693篇
  2002年   69370篇
  2001年   108743篇
  2000年   111452篇
  1999年   93498篇
  1998年   26991篇
  1997年   23660篇
  1996年   24055篇
  1995年   22715篇
  1994年   20894篇
  1993年   19714篇
  1992年   72004篇
  1991年   70073篇
  1990年   68393篇
  1989年   65663篇
  1988年   60303篇
  1987年   59126篇
  1986年   55219篇
  1985年   53007篇
  1984年   39312篇
  1983年   33398篇
  1982年   19859篇
  1979年   35869篇
  1978年   25651篇
  1977年   21233篇
  1976年   20333篇
  1975年   21817篇
  1974年   26149篇
  1973年   24804篇
  1972年   23201篇
  1971年   22037篇
  1970年   20253篇
  1969年   19321篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
Background: The aim of this study was to determine whether pre-existing diabetes mellitus increases the risk of rejection, infection and/or death in cystic fibrosis patients undergoing bilateral sequential single-lung transplantation.
Methods: A retrospective audit of 25 consecutive patients with cystic fibrosis who underwent bilateral sequential single-lung transplantation between 1 January 2003 and 31 December 2005 at a tertiary referral hospital was carried out.
Results: Although 32% patients had diabetes diagnosed before lung transplantation, 92% had random blood glucose levels ≥11.1 mmol/L requiring insulin during admission. Patients with pre-existing diabetes had increased infection-related (3.9 vs 1.2, P = 0.01) and putative rejection-related (1.4 vs 0.5, P = 0.04) hospital admissions post-transplantation compared with those without diabetes pre-transplant. During the period of observation, four of eight patients with a prior diagnosis of diabetes died compared with none of 17 patients without prior diabetes ( P = 0.0055).
Conclusion: Almost all cystic fibrosis patients develop hyperglycaemia after lung transplantation, but patients with prior diabetes have more complication-related admissions to hospital and a higher mortality rate.  相似文献   
992.
Aims: To explore the quality of life in patients treated medically during the acute phase of pancreatitis as well as at 2 and 12 months after discharge from the hospital. Patients: 40 patients were studied. The etiology of the pancreatitis was biliary causes in 31 patients and non-biliary causes in 9; mild disease was present in 29 patients and severe disease in 11. 30 patients completed the two surveys at 2 and 12 months after hospital discharge. Methods: The SF-12 and EORTC QLQ-C30 questionnaires were used for the purpose of the study. Results: The two physical and mental component summaries of SF-12, all the domains of EORTC QLQ-C30 (except for physical functioning and cognitive functioning) and some symptom scales of EORTC QLQ-C30 (fatigue, nausea/ vomiting, pain, and constipation) were significantly impaired during the acute phase of pancreatitis. There was a significant improvement in the SF-12 physical component summary, and global health, role functioning, social functioning, nausea/vomiting, pain, dyspnea, and financial difficulties (EORTC QLQ-C30) at 2 months after discharge as compared to the basal evaluation. Similar results were found after 12 months except for the mental component score at 12-month evaluation, which was significantly impaired in acute pancreatitis patients in comparison to the norms. The physical functioning of the EORTC QLQ-C30 at basal evaluation was significantly impaired in patients with severe pancreatitis in comparison to patients with mild pancreatitis. Conclusions: Two different patterns can be recognized in the quality of life of patients with acute pancreatitis: physical impairment is immediately present followed by mental impairment which appears progressively in the follow-up period.  相似文献   
993.
994.
995.
Background: In elderly patients, opioids may cause prominent postoperative sedation and respiratory depression. We evaluated the influence of age on the effects of opioids and plasma concentrations of fentanyl and oxycodone in cardiac surgery patients.
Methods: Thirty (≥75 years, gender M9/F21) and 20 (≤60 years, gender M20/F0) patients scheduled to undergo cardiac surgery. A standard anesthesia with fentanyl as an opioid was used. Fentanyl plasma concentrations were measured at the end of surgery and 2 h later. After tracheal extubation, when the pain intensity was at least moderate, blood samples for fentanyl and oxycodone plasma concentration measurements were taken. Thereafter, oxycodone hydrochloride 0.05 mg/kg i.v. was administered. After 15 and 45 min, pain intensity, sedation and oxycodone plasma concentration were determined. This test protocol was repeated twice.
Results: The elderly had a higher plasma concentration of fentanyl at the end of surgery than younger patients (5.7±2.2 vs. 3.8±1.2 ng/ml, P =0.001). The plasma concentrations of oxycodone were comparable between the groups. The interval between the second and the third oxycodone dose was longer in the elderly patients ( P =0.036). Pain intensity on the verbal rating scale was lower at the 45-min assessment point after all three oxycodone test doses ( P =0.008) and sedation scores were significantly higher after the third dose in the elderly patients ( P =0.035).
Conclusions: In elderly patients, the plasma concentration of fentanyl was higher but plasma levels of oxycodone were at a similar level compared with middle-aged patients. However, the elderly patients had less pain and were more sedated after doses of oxycodone.  相似文献   
996.
997.
998.
999.
1000.
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