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   11873篇
  免费   1141篇
  国内免费   18篇
耳鼻咽喉   94篇
儿科学   435篇
妇产科学   321篇
基础医学   1543篇
口腔科学   349篇
临床医学   1357篇
内科学   2160篇
皮肤病学   387篇
神经病学   1014篇
特种医学   415篇
外科学   1764篇
综合类   282篇
一般理论   12篇
预防医学   1302篇
眼科学   192篇
药学   850篇
中国医学   10篇
肿瘤学   545篇
  2021年   196篇
  2020年   103篇
  2019年   159篇
  2018年   203篇
  2017年   140篇
  2016年   154篇
  2015年   126篇
  2014年   237篇
  2013年   344篇
  2012年   530篇
  2011年   523篇
  2010年   296篇
  2009年   265篇
  2008年   493篇
  2007年   541篇
  2006年   517篇
  2005年   437篇
  2004年   453篇
  2003年   458篇
  2002年   464篇
  2001年   369篇
  2000年   445篇
  1999年   370篇
  1998年   153篇
  1997年   149篇
  1996年   100篇
  1995年   107篇
  1994年   100篇
  1993年   130篇
  1992年   282篇
  1991年   285篇
  1990年   278篇
  1989年   326篇
  1988年   238篇
  1987年   258篇
  1986年   222篇
  1985年   261篇
  1984年   164篇
  1983年   132篇
  1982年   113篇
  1981年   120篇
  1980年   92篇
  1979年   167篇
  1978年   127篇
  1977年   114篇
  1976年   91篇
  1975年   96篇
  1974年   94篇
  1973年   112篇
  1972年   98篇
排序方式: 共有10000条查询结果,搜索用时 578 毫秒
61.
An untested assumption of malingering research is that persons who feign mental illness will not attempt to fake a particular disorder, but will be content to fabricate non-specific and possibly global psychiatric impairment. We tested the effectiveness of the Structured Interview of Reported Symptoms (SIRS) to detect feigning of three diagnostic groupings: schizophrenia, mood disorders, and PTSD on 45 psychologically knowledgeable correctional residents. We found that the SIRS maintained its powers of discrimination with respect to clinical samples. Similar research on faking specific disorders is needed on the MMPI-2 and other psychological measures.  相似文献   
62.
The skeletal remains of past populations provide an important source of information on the natural history of disease. Relatively few cases of bone tumours have been reported in archaeological material. This paper describes one of the oldest occurrences of osteochondroma to have been identified in a human skeleton.  相似文献   
63.
Hidradenitis suppurativa, a chronic inflammatory condition of the apocrine gland follicles, may rarely be complicated by pyoderma gangrenosum (PG). We report such a case, in which the immunosuppressant cyclosporin A (CyA) was given to treat PG and a dramatic improvement occurred in the patient's intractable perineal HS.  相似文献   
64.
65.
66.
cDNA clones corresponding to mRNA for rat olfactory marker protein (OMP) were isolated from a cDNA library. The library was constructed from olfactory mucosa poly(A)+ RNA enriched for OMP mRNA and cloned into a pBR322-derived plasmid, pMG5. OMP cDNA clones were detected by using a 17-base oligonucleotide probe that contained all 16 possible sequences coding for a known partial amino acid sequence of rat OMP. The identity of these clones was confirmed by hybrid-selected translation and nucleotide sequencing. The sequence of one clone was determined and contained the complete OMP coding region of 486 nucleotides followed by 1630 nucleotides of the 3' untranslated region. The 3' untranslated region included the polyadenylylation signal 16 nucleotides upstream of the poly(A) tail. No other ATG-initiated open reading frame larger than 20 codons was present in register. RNA blot analysis of olfactory mucosa poly(A)+ RNA using this clone as a probe indicated that the level of OMP mRNA, but not its size, declined significantly within a few days following olfactory bulbectomy. OMP mRNA was not detected in 14 nonolfactory rat tissues. Surprisingly, a small amount of OMP mRNA was observed in olfactory bulb. The presence of OMP mRNA in olfactory bulb was confirmed by in vitro translation and immunoprecipitation. These results suggest either that a previously undescribed population of neurons in the olfactory bulb synthesize OMP or that OMP mRNA is transported to the bulb by axonal transport.  相似文献   
67.
68.
An experimental drug, 1-(1,3-benzodioxol-5-ylcarbonyl)piperidine, that facilitates glutamatergic transmission in brain after systemic administration was tested for its effects on the induction of long-term potentiation in the hippocampus of rats. Intraperitoneal injections of the drug markedly increased the degree and duration of long-term potentiation; similar results were obtained with an analogue of 1-(1,3-benzodioxol-5-ylcarbonyl)piperidine that was also found to improve retention of memory in a radial maze task and in an odor-matching problem. These results define tools for enhancing long-term potentiation in vivo and confirm an important prediction from the hypothesis that long-term potentiation is a substrate of memory.  相似文献   
69.
Autoradiographic techniques were used to test if positive modulators of AMPA-type glutamate receptors have regionally differentiated effects on ligand binding. Cyclothiazide, a drug with ten fold greater effects on `flip' than `flop' splice variants of the receptors, had unequal effects across the subdivisions of hippocampus; i.e., it reduced [3H]AMPA binding in field CA3 with an EC50 of 24 μM and in field CA1 and dentate gyrus with EC50s between 60 and 100 μM. The EC50 for the drug's influence on binding was also significantly lower in the superficial than in the deeper layers of the neocortex, though these differences were not as pronounced as those in the hippocampus. The ampakine CX614, a compound with a modest preference for flop variants, had a slightly lower EC50 for its effects on [3H]AMPA binding in CA1 than in CA3. This result was confirmed with [3H]fluorowillardiine binding. The effects of the ampakine in neocortex tended to be greater in the deeper than superficial layers but this did not reach statistical significance. These results indicate that differential effects of modulators on AMPA receptor subunits are reflected in their relative potency across brain subdivisions. This raises the possibility that subclasses of positive modulators will exhibit a measurable degree of selectivity in their physiological and behavioral influences.  相似文献   
70.
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