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   2731篇
  免费   122篇
  国内免费   54篇
  2023年   63篇
  2022年   56篇
  2021年   89篇
  2020年   54篇
  2019年   73篇
  2018年   61篇
  2017年   58篇
  2016年   33篇
  2015年   61篇
  2014年   83篇
  2013年   120篇
  2012年   96篇
  2011年   97篇
  2010年   76篇
  2009年   103篇
  2008年   126篇
  2007年   129篇
  2006年   131篇
  2005年   88篇
  2004年   120篇
  2003年   89篇
  2002年   94篇
  2001年   65篇
  2000年   73篇
  1999年   65篇
  1998年   59篇
  1997年   53篇
  1996年   51篇
  1995年   63篇
  1994年   58篇
  1993年   45篇
  1992年   38篇
  1991年   54篇
  1990年   46篇
  1989年   50篇
  1988年   35篇
  1987年   24篇
  1986年   27篇
  1985年   24篇
  1984年   23篇
  1982年   24篇
  1981年   20篇
  1980年   15篇
  1979年   13篇
  1978年   17篇
  1977年   12篇
  1976年   9篇
  1973年   10篇
  1972年   8篇
  1971年   9篇
排序方式: 共有2907条查询结果,搜索用时 15 毫秒
1.
《Developmental cell》2021,56(21):2952-2965.e9
  1. Download : Download high-res image (167KB)
  2. Download : Download full-size image
  相似文献   
2.
Summary The horseradish-peroxidase (HRP) technique was used to visualize the cell bodies of axons projecting to the goldfish pituitary. Following intravenous injections of HRP, HRP reaction products were observed in axons of the rostral pars distalis, proximal pars distalis, neurointermediate lobe, pituitary stalk and in axons coursing from the pituitary into the hypothalamus. HRP-labelled cells in the brain were localized in two regions only — the nucleus preopticus (NPO) pars magnocellularis and pars parvocellularis, and the nucleus lateralis tuberis (NLT) of the hypothalamus. These observations suggest that the NPO and NLT are the source of the neurosecretory innervation of the goldfish pituitary.  相似文献   
3.
《Cell reports》2020,30(1):164-172.e4
  1. Download : Download high-res image (143KB)
  2. Download : Download full-size image
  相似文献   
4.
Parkin mutations produce Parkinson’s disease (PD) in humans and nigrostriatal dopamine lesions related to increased free radicals in mice. We examined the effects of NP7, a synthetic, marine derived, free radical scavenger which enters the brain, on H2O2 toxicity in cultured neurons and glia from wild-type (WT) and parkin null mice (PK-KO).NP7, 5-10 μM, prevented the H2O2 induced apoptosis and necrosis of midbrain neuronal and glial cultures from WT and PK-KO mice. NP7 suppressed microglial activation and the H2O2 induced drop-out of dopamine neurons. Furthermore, NP7 prevented the increased phosphorylation of ERK and AKT induced by H2O2. NP7 may be a promising neuroprotector against oxidative stress in PD.  相似文献   
5.
6.
7.
《Current biology : CB》2020,30(5):827-839.e4
  1. Download : Download high-res image (204KB)
  2. Download : Download full-size image
  相似文献   
8.
Using immunohistochemical labeling against acetylated a‐tubulin and serotonin in combination with confocal laser scanning microscopy and 3D‐reconstruction, we investigated the temporary freshwater pond inhabitant Branchinella sp. (Crustacea: Branchiopoda: Anostraca) for the first time to provide detailed data on the development of the anostracan nervous system. Protocerebral sense organs such as the nauplius eye and frontal filament organs are present as early as the hatching stage L0. In the postnaupliar region, two terminal pioneer neurons grow from posterior to anterior to connect the mandibular neuromeres. The first protocerebral neuropil to emerge is not part of the central complex but represents the median neuropil, and begins to develop from L0+ onwards. In stage L3, the first evidence of developing compound eyes is visible. This is followed by the formation of the visual neuropils and the neuropils of the central complex in the protocerebrum. From the deutocerebral lobes, the projecting neuron tract proceeds to both sides of the lateral protocerebrum, forming a chiasma just behind the central body. In the postnaupliar region, the peripheral nervous system, commissures and connectives develop along an anterior–posterior gradient after the fasciculation of the terminal pioneer neurons with the mandibular neuromere. The peripheral nervous system in the thoracic segments consists of two longitudinal neurite bundles on each side which connect the intersegmental nerves, together with the ventral nervous system forming an orthogon‐like network. Here, we discuss, among other things, the evidence of a fourth nauplius eye nerve and decussating projecting neuron tract found in Branchinella sp., and provide arguments to support our view that the crustacean frontal filament (organ) and onychophoran primary antenna are homologous. J. Morphol. 277:1423–1446, 2016. © 2016 Wiley Periodicals, Inc.  相似文献   
9.
10.
Upregulation of small heat-shock proteins (sHsps) in response to cellular stress is one mechanism to increase cell viability. We previously described that cultured rat hippocampal neurons express five of the 11 family members but only upregulate two of them (HspB1 and HspB5) at the protein level after heat stress. Since neurons have to cope with many other pathological conditions, we investigated in this study the expression of all five expressed sHsps on mRNA and protein level after sublethal sodium arsenite and oxidative and hyperosmotic stress. Under all three conditions, HspB1, HspB5, HspB6, and HspB8 but not HspB11 were consistently upregulated but showed differences in the time course of upregulation. The increase of sHsps always occurred earlier on mRNA level compared with protein levels. We conclude from our data that these four upregulated sHsps (HspB1, HspB5, HspB6, HspB8) act together in different proportions in the protection of neurons from various stress conditions.  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