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   12212篇
  免费   438篇
  国内免费   37篇
耳鼻咽喉   155篇
儿科学   189篇
妇产科学   305篇
基础医学   2405篇
口腔科学   237篇
临床医学   689篇
内科学   1339篇
皮肤病学   427篇
神经病学   1019篇
特种医学   1618篇
外科学   1590篇
综合类   51篇
一般理论   2篇
预防医学   892篇
眼科学   109篇
药学   1158篇
中国医学   94篇
肿瘤学   408篇
  2023年   50篇
  2022年   56篇
  2021年   110篇
  2020年   77篇
  2019年   109篇
  2018年   251篇
  2017年   164篇
  2016年   223篇
  2015年   172篇
  2014年   293篇
  2013年   477篇
  2012年   840篇
  2011年   1174篇
  2010年   533篇
  2009年   223篇
  2008年   872篇
  2007年   1034篇
  2006年   999篇
  2005年   821篇
  2004年   730篇
  2003年   717篇
  2002年   621篇
  2001年   379篇
  2000年   479篇
  1999年   268篇
  1998年   87篇
  1997年   56篇
  1996年   42篇
  1995年   48篇
  1994年   28篇
  1993年   24篇
  1992年   22篇
  1991年   23篇
  1990年   30篇
  1989年   23篇
  1988年   25篇
  1986年   19篇
  1985年   31篇
  1984年   25篇
  1983年   23篇
  1982年   32篇
  1981年   30篇
  1980年   30篇
  1979年   27篇
  1978年   28篇
  1976年   20篇
  1975年   27篇
  1974年   20篇
  1973年   18篇
  1963年   19篇
排序方式: 共有10000条查询结果,搜索用时 312 毫秒
41.
Left Bochdalek hernia is a serious and complex condition with high mortality. In most cases, it presents in the neonatal period and is seldom found later in life when symptomatology, usually after an asymptomatic period, is quite different and the prognosis excellent. The embryological development of left Bochdalek hernia suggests the presence of abdominal content in the left pleural cavity before birth. The type of clinical presentation and the prognosis depend on the time of visceral herniation. This study presents two cases of left Bochdalek hernia with delayed presentation. In both cases, after surgical reposition of the hernia, a small congenital diaphragmatic defect was found hidden between the rims of diaphragm. This indicates the possibility for the abdominal content to enter the left pleural cavity at the time of presentation.  相似文献   
42.
Variation of the photoactivation rate across radiation fields of three different bremsstrahlung beams of two medical accelerators has been measured, making use of the photonuclear reactions in natural indium probes: 115In(y,y')115mIn and 115In(y,n)114mIn. The third nuclear reaction, 115In(n,y)116mIn, was used to detect the presence of neutrons in the photon beam and to estimate the spatial distribution of thermal and fast neutrons in the patient plane as a function of collimator opening.  相似文献   
43.
44.
45.
46.
47.
Anatomical variations in the dimensions of different brain structures have been correlated with clinical syndromes. This study on the parameters of normal and abnormal cavum septi pellucidi (CSP) can be of clinical significance. We obtained 479 brains from autopsied persons (310 males and 169 females, 377 normal or asymptomatic and 102 abnormal or symptomatic persons, aged 22-89 years) and observed that 110 brains (75 males and 35 females) had CSP. These cava were classified into two groups depending on the past medical histories of the autopsied person: 40 asymptomatic and 70 symptomatic cava. We have defined symptomatic cava as those in autopsied persons who had known past medical history of psychiatric or neurological disease. Asymptomatic cava were in autopsied persons who had no known past medical history of psychiatric or neurological disease. The CSP parameters (length, width, depth) of the symptomatic and asymptomatic groups were measured and were statistically analyzed. Analysis showed that the cava in the symptomatic group were significantly longer and wider. Discriminant function analysis was used to derive a mathematical formula to classify CSP into an asymptomatic or symptomatic group based on length and width measurements of the cavum.  相似文献   
48.
Neonatal treatments can disrupt prepulse inhibition (PPI) of startle response later in life. Alpha2A-adrenergic receptors (alpha2A-ARs) regulate the release of brain neurotransmitters that may influence PPI. The authors examined the effects of short-term reduction in the neonatal brainstem alpha2A-ARs on subsequent development of this receptor system and acoustic startle reflex in rats. Administration of antisense oligodeoxynucleotide complementary to the alpha2A-ARs on Days 2-4 of life reduced receptor expression in the brainstem by Day 5. The treatment increased alpha2-AR numbers in the cortex, hippocampus, and amygdala at 40 days of age, and in cortex and hypothalamus at 90 days of age. Transient increases in hippocampal and amygdalar alpha2-ARs were accompanied by attenuation of acoustic startle response and impairment of PPI.  相似文献   
49.
50.
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