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   520903篇
  免费   64796篇
  国内免费   28422篇
耳鼻咽喉   7894篇
儿科学   10144篇
妇产科学   6544篇
基础医学   43914篇
口腔科学   7573篇
临床医学   78838篇
内科学   96710篇
皮肤病学   11378篇
神经病学   32458篇
特种医学   19920篇
外国民族医学   224篇
外科学   72939篇
综合类   70175篇
现状与发展   154篇
一般理论   31篇
预防医学   34386篇
眼科学   13938篇
药学   41511篇
  436篇
中国医学   24423篇
肿瘤学   40531篇
  2024年   1918篇
  2023年   9853篇
  2022年   15524篇
  2021年   21230篇
  2020年   20143篇
  2019年   13798篇
  2018年   19215篇
  2017年   18701篇
  2016年   18868篇
  2015年   24920篇
  2014年   35996篇
  2013年   34265篇
  2012年   33573篇
  2011年   37110篇
  2010年   31548篇
  2009年   31412篇
  2008年   26978篇
  2007年   24960篇
  2006年   26447篇
  2005年   22829篇
  2004年   15604篇
  2003年   14110篇
  2002年   11977篇
  2001年   12281篇
  2000年   11295篇
  1999年   11571篇
  1998年   8909篇
  1997年   8530篇
  1996年   7295篇
  1995年   6903篇
  1994年   5065篇
  1993年   3579篇
  1992年   3788篇
  1991年   3522篇
  1990年   2838篇
  1989年   2724篇
  1988年   2290篇
  1987年   2027篇
  1986年   1834篇
  1985年   1385篇
  1984年   911篇
  1983年   788篇
  1982年   652篇
  1981年   567篇
  1980年   473篇
  1979年   460篇
  1978年   401篇
  1977年   449篇
  1975年   306篇
  1972年   339篇
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
31.
The efficacy and safety of ketoprofen and paracetamol were compared for the treatment of acute migraine in a randomized, double-blind study of 64 patients. Thirty-four patients received ketoprofen 100 mg intramuscularly, and 30 patients received paracetamol 500 mg intramuscularly. Partial or complete relief of pain and other symptoms was achieved 15 to 20 minutes after administration in the ketoprofen group and within 35 minutes in the paracetamol group. Complete relief of pain was achieved within 30 to 40 minutes after ketoprofen in 28 patients (82.5%) compared to 5 patients (17.5%) in the paracetamol group. Six of the patients treated with ketoprofen needed a second dose for complete relief of pain during the 4-hour follow-up period. Side effects were rare and minimal. Our findings suggest that ketoprofen produced statistically significant benefit in the treatment of acute migraine.  相似文献   
32.
33.
34.
35.
36.
37.
Positron emission tomography (PET) with fluorodeoxyglucose (FDG), magnetic resonance imaging (MRI), and CT were carried out in a patient with Alzheimer's disease 16 months before he died. At autopsy, the gross appearance of the brain correlated with MRI and CT, which showed some regional atrophy. These were much less revealing than PET, which correlated with microscopic findings of neuronal loss and proliferation of glia. In areas of moderately impaired local cerebral metabolic rate of glucose, as revealed by reduced FDG uptake, there was some gliosis, primarily around the numerous senile plaques. In areas of severe metabolic impairment, there was a profound loss of neurons, extensive gliosis, and a diminished appearance of plaques. PET-FDG is a better measure of the severity of Alzheimer's disease than MRI or CT, because it reflects the degree of neuronal pathology.  相似文献   
38.
J S Li 《中华外科杂志》1989,27(10):629-33, 640
Serum aminogram changes were prospectively studied in 95 patients with enteric fistula and intraabdominal infection who was under total parenteral nutrition (TPN) therapy with Anfuming 14s. In patients with sepsis and starvation, the aminogram showed remarkably low total free amino acids before TPN therapy. In 81 survivors, free amino acids increased gradually to normal in 2 weeks after use of TPN and in 14 dead cases increased rapidly to a significantly higher peak at terminal stage. Both in survivors and nonsurvivors, phenylalanine level remained high during the study. In response to infection, proline was also elevated but to a lesser degree; the ratio of branched chain amino acid (BCAA) to aromatic amino acid (AAA) was lower than normal and the decrease of arginine was parallel to the severity of infection. We conclude that the ideal amino acids preparation for the starvated and septic patients should be high in BCAA and arginine but low in phenylalanine, administration of inappropriate exogenous amino acids in decompensated metabolic septic patients may bring about more harm than benefit, and in septic patients that the levels of serum phenylalanine and proline are elevated persistently along with the decrease of arginine level is a useful prognostic indication.  相似文献   
39.
40.
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