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   23402篇
  免费   1239篇
  国内免费   109篇
耳鼻咽喉   276篇
儿科学   565篇
妇产科学   376篇
基础医学   2834篇
口腔科学   621篇
临床医学   1664篇
内科学   6397篇
皮肤病学   444篇
神经病学   1963篇
特种医学   515篇
外科学   3497篇
综合类   149篇
一般理论   9篇
预防医学   1723篇
眼科学   521篇
药学   1284篇
  1篇
中国医学   61篇
肿瘤学   1850篇
  2023年   175篇
  2022年   437篇
  2021年   801篇
  2020年   387篇
  2019年   691篇
  2018年   829篇
  2017年   490篇
  2016年   522篇
  2015年   667篇
  2014年   824篇
  2013年   1098篇
  2012年   1827篇
  2011年   1897篇
  2010年   1005篇
  2009年   951篇
  2008年   1510篇
  2007年   1520篇
  2006年   1427篇
  2005年   1368篇
  2004年   1219篇
  2003年   1080篇
  2002年   949篇
  2001年   316篇
  2000年   284篇
  1999年   287篇
  1998年   188篇
  1997年   166篇
  1996年   138篇
  1995年   109篇
  1994年   97篇
  1993年   81篇
  1992年   136篇
  1991年   145篇
  1990年   129篇
  1989年   95篇
  1988年   94篇
  1987年   83篇
  1986年   91篇
  1985年   80篇
  1984年   62篇
  1983年   52篇
  1982年   48篇
  1981年   37篇
  1980年   25篇
  1979年   37篇
  1978年   24篇
  1977年   35篇
  1976年   22篇
  1975年   27篇
  1974年   36篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
51.
This double-blind study compared ampicillin-sulbactam 3 g versus cefoxitin 2 g in 136 adult patients at risk for developing an infection after abdominal surgery. Separate randomization schedules were used for colorectal, upper gastrointestinal/biliary, and other abdominal procedures. Study antibiotics were administered within 30 minutes before incision and repeated 6 hours later. Patients having colorectal surgery received a third dose of antibiotic 6 hours after the second. Efficacy evaluations were made on 123 patients, 62 in the ampicillin-sulbactam group and 61 in the cefoxitin group. The overall postoperative infection rates were 12.9% for ampicillin-sulbactam and 9.8% for cefoxitin (p>0.05); one wound infection occurred in each group. Adverse events were experienced by 13.2% of the ampicillin-sulbactam and 19.1% of the cefoxitin recipients (p>0.05). Cost-minimization analysis revealed that ampicillin-sulbactam was a cost-effective alternative to cefoxitin for the prevention of infection after abdominal surgery.  相似文献   
52.
53.
54.
55.
56.
A 28-month-old boy, weighing 11 kg, with severe dilated cardiomyopathy, was transplanted on December 1995. Hypertension and supraventricular tachycardia were detected in the immediate post-operative period, with favorable outcome. After 5 months of clinically asymptomatic follow-up, a dilation in the ascending aorta was observed on routine echocardiogram. Nuclear magnetic resonance imaging (NMRI) confirmed an ascending aortic aneurysm, with a diameter of 38 mm. An operation was performed, a bovine pericardium patch was sutured with reconstruction of the aortic wall, excluding the aneurysm. Good recovery was obtained and the child was discharged on Day 7 postoperatively. A post-operative echocardiogram showed absence of the aortic aneurysm and good surgical results. Another NMRI was done 5 months later, showing an intact ascending aorta. After 64 months, the patients clinical condition was confirmed as normal by echocardiogram. Surgical treatment was successful and the positive results have been maintained.  相似文献   
57.
58.
We report the first case in the world literature of a patient with an atrial septal defect, severe pulmonary hypertension, and equalization of pulmonary and systemic pressures, who underwent successful closure of an ASD following prolonged therapy with the intravenous vasodilator epoprostenol. Judicious use of continuous prostacyclin in apparently inoperable patients with congenital heart disease may be associated with significant reversal of pulmonary hypertension, and conversion to an operable state.  相似文献   
59.
60.
OBJECTIVE: Several studies have shown that repetitive transcranial magnetic stimulation (rTMS) over the dorsolateral prefrontal cortex (DLPFC) is effective in the treatment of depression in patients with Parkinson disease (PD). However, since research into the effect of this type of rTMS regime on motor function is limited, we studied the effect of rTMS over the DLPFC on the motor functions in PD patients. METHODS: Thirteen patients were randomly assigned into 2 groups, one receiving real-rTMS (90% of resting motor threshold, 10 Hz, 450 pulses-day for 10 consecutive days) over the DLPFC contralateral to the more affected side, and the other group receiving sham-rTMS. Assessment included a clinical motor evaluation using part III of the Unified Parkinson's Disease Rating Scale (UPDRS), and several motor tasks. The UPDRS was applied before and after 10 days of rTMS. Finger tapping, reach movement, grip movement and gait were measured in each session before and after the rTMS over the 10 day period. RESULTS: Statistical analysis (ANOVA for repeated measures; group *day *side *rTMS) only showed a significant effect for finger tapping, reach movement and gait for the factor day. No significant change was reported for the UPDRS in any group. CONCLUSIONS: Application of rTMS over the DLPFC as a 10 day course had no significant effect on motor functions and clinical motor status, and the improvement in performance of motor tasks can be attributed to the effects of practice. SIGNIFICANCE: rTMS over the DLPFC did not lead to any motor improvement in PD patients.  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