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   994篇
  免费   64篇
耳鼻咽喉   15篇
儿科学   20篇
妇产科学   19篇
基础医学   115篇
口腔科学   25篇
临床医学   86篇
内科学   139篇
皮肤病学   8篇
神经病学   147篇
特种医学   30篇
外科学   135篇
综合类   2篇
一般理论   3篇
预防医学   54篇
眼科学   8篇
药学   56篇
肿瘤学   196篇
  2021年   4篇
  2020年   4篇
  2019年   9篇
  2018年   13篇
  2017年   12篇
  2016年   12篇
  2015年   12篇
  2014年   15篇
  2013年   26篇
  2012年   43篇
  2011年   38篇
  2010年   16篇
  2009年   21篇
  2008年   47篇
  2007年   36篇
  2006年   44篇
  2005年   42篇
  2004年   34篇
  2003年   37篇
  2002年   31篇
  2001年   30篇
  2000年   29篇
  1999年   41篇
  1998年   15篇
  1997年   19篇
  1996年   12篇
  1995年   20篇
  1994年   16篇
  1993年   11篇
  1992年   32篇
  1991年   28篇
  1990年   24篇
  1989年   32篇
  1988年   33篇
  1987年   18篇
  1986年   17篇
  1985年   26篇
  1984年   20篇
  1983年   10篇
  1982年   21篇
  1981年   6篇
  1980年   7篇
  1979年   17篇
  1978年   12篇
  1977年   12篇
  1976年   6篇
  1975年   12篇
  1974年   9篇
  1973年   7篇
  1971年   6篇
排序方式: 共有1058条查询结果,搜索用时 343 毫秒
51.
A liveborn triploid infant   总被引:1,自引:0,他引:1  
  相似文献   
52.
53.
Two patients with dystrophia myotonica and pleomorphic adenoma of the parotid gland are described. The probability that this coincidence could be due to chance is less than 1 to 1,000 (P less than or equal to 0.001). There are several reports in the literature of the association of myotonic dystrophy with neoplasia. The reason for their association is not understood.  相似文献   
54.
SYNOPSIS
The preventive effect of propranolol on migraine attacks was compared to placebo in a double-blind cross-over trial. Thirty-two patients with serious and prolonged migraine participated in the 12-week study. The effect of propranolol was significantly better than that of placebo. The number of migraine attacks during the propranolol period was reduced in 22 patients (69%), and in 11 of these (34%) a reduction of more than 50% was seen. The intensity of headache was significantly reduced during the propranolol period. The intake of analgesics and preparations containing ergotamine was significantly reduced during the propranolol period also. No serious side effects were noted.  相似文献   
55.
During chronic relapsing experimental allergic encephalomyelitis (r-EAE) in guinea pigs, serum IgM and IgG concentrations increased markedly early in disease. Serum IgM and IgG increased similarly in control animals immunized with Freund's incomplete adjuvant (FIA) and Mycobacterium tuberculosis (MT). In the chronic phase of r-EAE but not in control animals, elevated IgM was also found in central nervous system (CNS) extracts, suggesting intrathecal IgM synthesis. IgG antibodies against myelin and myelin basic protein (MBP) were regularly detected in r-EAE sera from day 21 post inoculation (p.i.), reaching maximum levels in the early chronic phase. IgG antibodies against galactocerebroside (GC) and galactose appeared in some r-EAE sera. Oligoclonal IgG bands were demonstrated in all r-EAE guinea pig sera 21-26 days p.i. The bands in serum decreased in number and strength in the chronic phase. They could be traced to antibodies against MT in 4 of 10 animals, but not to antibodies against myelin, MBP, GC or galactose. Oligoclonal IgG bands were also regularly visualized in r-EAE CNS 124 days p.i., suggesting persistent intrathecal IgG synthesis. They varied in number and migration between different regions of individual CNS. Oligoclonal CNS IgG was related to antibodies against MT in only one of 7 animals, and in no case to antibodies against myelin.  相似文献   
56.
In 21 women undergoing simultaneous urethrocystometry because of dysuria, urge, and difficulties to empty the bladder, the effects of prostaglandin E2 (PGE2) applied locally in the bladder and urethra were investigated. In all 9 patients receiving PGE2 intravesically, the bladder pressure increased. Simultaneously, there was a signficant decrease in maximum urethral pressure (p less than 0.05), and in urethral closure pressure (p less than 0.005). Residual urine decreased in the 4 patients, in whom it exceeded 50 ml before administration. All 12 patients receiving PGE2 intraurethrally showed a decrease in maximum urethral pressure). There was a significant increase in bladder pressure (p less than 0.05); urethral closure pressure decreased in all patients. Bladder capacity decreased significantly (p less than 0.01). Residual urine exceeding 50 ml was found in 6 patients; it decreased in 4 after PGE2 administration. It is concluded that PGE2 applied intraurethrally can decrease the intraurethral pressure and increase the bladder pressure without side effects. By these actions, the drug might be useful for facilitating bladder emptying in patients with acute retention of urine.  相似文献   
57.
This study aimed to examine the relationship between craniofacial dysmorphology and anomalies of brain morphology in schizophrenia. Assessments of craniofacial dysmorphology and magnetic resonance imaging of brain were performed independently of each other and blind to each other in 24 males with schizophrenia and 16 male controls. Ventricular cerebrospinal fluid volume was negatively correlated with total dysmorphology score in males with schizophrenia (i.e., the larger the ventricular cerebrospinal fluid volume, the lower the total dysmorphology score) but not in male controls. These findings suggest that craniofacial dysmorphology and anomalies of brain morphology may be associated with independent processes in the etiology of schizophrenia.  相似文献   
58.
59.
60.
The detailed mechanisms behind the resistance of malignant gliomas to therapy are not known. Inherent resistance to apoptosis is, however, one plausible explanation. In the present study we tried to delineate the molecular defects and to induce apoptosis by inducible caspases in three apparently apoptosis resistant glioma cell lines. U-105 MG, U-251 MG, and SF-767 were resistant to Fas-induced apoptosis as shown by the lack of Fas-induced cell death, morphological changes, annexin-V reactivity, Parp cleavage, caspase-3 cleavage, and caspase-3 activation. The glioma cells showed no consistent down-regulation of the pro-apoptotic proteins Fas, Fadd, caspase-3, caspase-8, caspase-9, Apaf-1, Bid, Bad, or Bax, and no consistent up-regulation of the anti-apoptotic proteins Bcl-x or Bcl-2. In U-105 MG, Fas was, however, not detected at the cell surface indicating intracellular retention. To assess if the apoptotic blocks could be by-passed, we introduced the so-called artificial death switches, i.e., inducible caspases and Fadd, into the glioma cells. Synthetic activation of inducible caspase-3, but not of caspase-8, resulted in apoptosis in the three glioma cell lines and inducible Fadd induced apoptosis in SF-767. The results were consistent with a block in the apoptotic signaling pathways of glioma cells between caspase-8 and caspase-3 activation, and that inducible Fadd could induce caspase-8 independent apoptosis in some cells. Apparently resistant glioma cells could thus be induced to undergo apoptosis by activation of appropriate death switches. This might have implications for the design of future therapeutic strategies.  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