全文获取类型
收费全文 | 982篇 |
免费 | 31篇 |
国内免费 | 56篇 |
专业分类
系统科学 | 6篇 |
丛书文集 | 25篇 |
教育与普及 | 18篇 |
理论与方法论 | 7篇 |
现状及发展 | 220篇 |
研究方法 | 1篇 |
综合类 | 789篇 |
自然研究 | 3篇 |
出版年
2024年 | 2篇 |
2023年 | 4篇 |
2022年 | 5篇 |
2021年 | 6篇 |
2020年 | 6篇 |
2019年 | 10篇 |
2018年 | 4篇 |
2017年 | 4篇 |
2016年 | 8篇 |
2015年 | 12篇 |
2014年 | 32篇 |
2013年 | 18篇 |
2012年 | 57篇 |
2011年 | 59篇 |
2010年 | 41篇 |
2009年 | 66篇 |
2008年 | 75篇 |
2007年 | 77篇 |
2006年 | 76篇 |
2005年 | 65篇 |
2004年 | 51篇 |
2003年 | 48篇 |
2002年 | 50篇 |
2001年 | 54篇 |
2000年 | 27篇 |
1999年 | 32篇 |
1998年 | 20篇 |
1997年 | 19篇 |
1996年 | 17篇 |
1995年 | 16篇 |
1994年 | 15篇 |
1993年 | 16篇 |
1992年 | 11篇 |
1991年 | 13篇 |
1990年 | 8篇 |
1989年 | 11篇 |
1988年 | 4篇 |
1987年 | 5篇 |
1986年 | 15篇 |
1985年 | 4篇 |
1984年 | 5篇 |
1980年 | 1篇 |
排序方式: 共有1069条查询结果,搜索用时 15 毫秒
91.
92.
结合多年的司法实践,笔者提出了我国死亡赔偿金立法存在的问题,并讨论了设立统一死亡赔偿金制度的必要性及可行性,对此制度的设立提出了自己的建议。 相似文献
93.
M. K. Ticku 《Cellular and molecular life sciences : CMLS》1989,45(5):413-418
Summary Ethanol has a pharmacological profile similar to that of classes of drugs like benzodiazepines and barbiturates, which enhance GABAergic transmission in the mammalian CNS. Several lines of behavioral, electrophysiological and biochemical studies suggest that ethanol may bring about most of its effects by enhancing GABAergic transmission. Recently, ethanol at relevant pharmacological concentrations has been shown to enhance GABA-induced36Cl-fluxes in cultured spinal cord neurons, synaptoneurosomes and microsacs. These enhancing effects of ethanol were blocked by GABA antagonists. Ro15-4513, an azido analogue of classical BZ antagonist Ro15-1788, reversed most of the behavioral effects of ethanol and other effects involving36Cl-flux studies. The studies summarized below indicate that most of the pharmacological effects of ethanol can be related to its effects on GABAergic transmission. 相似文献
94.
In the early 1990s, the search for protein kinases led to the discovery of a novel family of non-receptor tyrosine kinases,
the Janus kinases or JAKs. These proteins were unusual because they contained two kinase homology domains and no other known
signaling modules. It soon became clear that these were not ‘just another’ type of kinase. Their ability to complement mutant
cells insensitive to interferons and to be activated by a variety of cytokines demonstrated their central signaling function.
Now, as we approach the end of the decade, it is evident from biochemical studies to knockout mice that JAKs play non-redundant
functions in development, differentiation, and host defense mechanisms. Here, recent progress is reviewed, with particular
emphasis on structure-function studies aimed at revealing how this family of tyrosine kinases is regulated. 相似文献
95.
李根亮 《长春师范学院学报》2011,(1):63-66
在清代小说中,经常有描写巫术活动害人和恶鬼吃人的情节。其中的巫术活动有独特的操作方式,或借助于巫师的超能力,或通过念咒语来实施。而恶鬼吃人的情节则表现出古人对于死亡的恐惧心理,体现了"鬼即邪恶"的文化观念。 相似文献
96.
The reliable three dimensional (3-D) structure of the extracellular ligand-binding domain (V106-P322) of human interleukin-6
receptor (hIL-6R) has been constructed by means of computer-guided homology modeling techniques using the crystal structure
of the extracellular ligand-binding region (K52–L251) of human growth hormone receptor (hGHR) as templet. The space location
of some key residues which influence the combination ability between the receptor and the ligand has been observed and the
effects of point mutagenesis of the four conservative cysteine residues on the space conformation are analyzed. The results
show that the space conformation of the side-chain carboxyl of E305 plays a key role in the ligand-binding ability. Furthermore,
the space conformation of the side-chain carboxyl of E305 is very important for the electrostatic potential complementarity
between hIL-6R and hIL-6 according to the docking method. 相似文献
97.
王瑜瑜 《沈阳大学学报:自然科学版》2009,21(1):64-68
通过考证认为:茅维生于1575年,卒于1645—1652年之间,确切卒年待考;“苕溪四逸”四人中,吴梦旸最为年长,其次为臧懋循、吴稼竳,二人年纪相仿,茅维年纪最小。 相似文献
98.
C. Kohlhauser W. Mosgoeller H. Hoeger G. Lubec B. Lubec 《Cellular and molecular life sciences : CMLS》1999,55(11):1491-1501
Perinatal asphyxia (PA) is considered to lead to a variety of brain disorders including spasticity, epilepsy, mental retardation,
and minimal brain disorder syndromes and may form the basis for psychiatric and neurodegenerative diseases later in life.
We examined markers for neuronal transmission involved in the pathomechanisms of PA and candidates as mediators for long-term
sequelae. We tested tyrosine hydroxylase (TH) and the vesicular monoamine transporter (VMAT) representing the monoaminergic
system, the vesicular acetylcholine transporter (VAChT), and the excitatory amino acid carrier 1 (EAAC1), a neuronal subtype
of the glutamate transporter, using immunohistochemistry on brain sections of rats subjected to graded PA. Three months following
the asphyxiant insult immunoreactive (IR)-TH was decreased in striatum, hippocampus, thalamus, frontal cortex, and cerebellum;
IR-VMAT was increased, and IR-VAChT was decreased in striatum. IR-EAAC1 glutamate transporter was increased in frontal cortex.
The cholinergic, monoaminergic, and glutamatergic changes, still observed 3 months after the asphyxiant insult, may reflect
their involvement in the pathomechanisms of PA and indicate mechanisms leading to long-term complications of PA. The variable
consequences on the individual markers in several brain regions may be explained by specific susceptibility of cholinergic,
monoaminergic, and glutamatergic neurons to the asphyxiant insult.
Received 16 March 1999; received after revision 20 May 1999; accepted 8 July 1999 相似文献
99.
M. Aglietta A. Stacchini F. Sanavio W. Piacibello 《Cellular and molecular life sciences : CMLS》1985,41(3):375-376
Summary The effect of 2 H2 receptor antagonists (ranitidine and cimetidine) on the in vitro growth of human granulomonopoietic precursors (CFU-GM) was studied. Ranitidine, although having an anti H2 receptor activity much greater than that of cimetidine, displays the same toxicity for CFU-GM.Acknowledgments. This work was supported by CNR, Rome, PFCCN and AIRC, Milan. 相似文献
100.
视黄酸受体γ基因的研究进展 总被引:3,自引:0,他引:3
对视黄酸受体家族、视黄酸受体γ基因和视黄酸受体γ同工型基因的结构以及视黄酸受体γ的表达与调控等方面进行了综述. 相似文献