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   61篇
  免费   0篇
  国内免费   2篇
现状及发展   32篇
研究方法   3篇
综合类   28篇
  2017年   2篇
  2015年   1篇
  2012年   2篇
  2011年   2篇
  2010年   1篇
  2008年   2篇
  2007年   4篇
  2006年   5篇
  2003年   2篇
  2002年   3篇
  2000年   3篇
  1996年   1篇
  1992年   4篇
  1990年   2篇
  1989年   3篇
  1988年   1篇
  1987年   1篇
  1986年   4篇
  1983年   1篇
  1982年   1篇
  1979年   6篇
  1978年   2篇
  1977年   3篇
  1975年   2篇
  1974年   1篇
  1970年   1篇
  1968年   2篇
  1967年   1篇
排序方式: 共有63条查询结果,搜索用时 234 毫秒
41.
Amino-acid sequence of slightly lysine-rich histone   总被引:16,自引:0,他引:16  
K Iwai  K Ishikawa  H Hayashi 《Nature》1970,226(5250):1056-1058
  相似文献   
42.
43.
Melt inclusions or glasses usually occur in spinel- facies peridotitic xenoliths entrained in the global ba- salts[1―4], and olivine phenocrysts and/or xenocrysts carried in the intermediate-mafic volcanic rocks (such as basalts, basaltic andesites and h…  相似文献   
44.
A diterpenoid, totarol (1), fromPodocarpus nagi was evaluated as an antioxidant. This diterpenoid inhibited autoxidation of linoleic acid. Mitochondrial and microsomal lipid peroxidation induced by Fe(III)-ADP/NADH or Fe(III)-ADP/NADPH were also inhibited. Nagilactone E (2), a norditerpene lactone isolated from the same source, had no antioxidative activity. Furthermore, totarol protected red cells against oxidative hemolysis. This diterpene was shown to be effective in protecting biological systems against oxidative stresses.  相似文献   
45.
46.
The innate immune system has evolved a variety of sensing mechanisms to detect and counter microbial invasion. These include the Toll-like receptor (TLR), cytoplasmic, nucleotide binding oligomerization domain (NOD)-like receptor and RIG-I-like helicase (RLH) pathways. However, how the cell detects pathogen-associated DNA to trigger host defense, including the production of interferon, remains to be fully clarified. Understanding these processes could have profound implications into how we understand and treat a variety of microbial-related disease, including viral-associated cancers, as well as autoimmune disorders. Recently, an endoplasmic reticulum-associated molecule referred to as STING (for stimulator of interferon genes) was isolated and shown to be critical for regulating the production of IFN in response to cytoplasmic DNA. Here, we review recent discoveries relating to the detection of foreign DNA, including the importance of the STING and inflammasome pathways and the triggering of innate signaling processes.  相似文献   
47.
Peptide YY (PYY) is thought to possess paracrine and endocrine functions. The highest concentrations of this peptide are in the colonic mucosa. The effect of PYY on electrolyte and water transport in the rat colon was studied in vivo. Under urethane anesthesia, rat colonic loops were perfused at a constant rate with physiological buffer solution containing phenol red as a nonabsorbable volume marker, and net movements of water, sodium, chloride and potassium in the perfused colon were determined every 10 min. Intravenous administration of PYY produced a dose-dependent increase in the net absorption of sodium chloride and water, as well as a decrease in the net secretion of potassium. PYY inhibited the reduction in net absorption of sodium chloride and water evoked by vasoactive intestinal peptide (VIP), but did not affect the VIP-evoked increase in net potassium secretion.These findings suggest that PYY acts as an enhancer of sodium chloride and water absorption and as an antagonist to VIP-induced secretion in the colon.  相似文献   
48.
Seo HS  Yang JY  Ishikawa M  Bolle C  Ballesteros ML  Chua NH 《Nature》2003,423(6943):995-999
  相似文献   
49.
Sulfur is an advantageous material as a promising next-generation positive electrode material for high-energy lithium batteries due to a high theoretical capacity of 1672 m A h g 1although its discharge potential is somewhat modest:ca.2 V vs Li/Lit.However,a sulfur positive electrode has some crucial problems for practical use,which are mainly attributed to the dissolution of its intermediate products in charge–discharge processes.In order to resolve the dissolution problem of lithium polysulfide,we attempted to synthesize a sulfur–microporous activated carbon(AC) composite positive electrode.Moreover,we have systematically researched the battery performance of sulfur–microporous AC positive electrode with variations of electrolytes as well as negative electrodes,and found its promising positive electrode performance for a nextgeneration rechargeable battery.  相似文献   
50.
Rancz EA  Ishikawa T  Duguid I  Chadderton P  Mahon S  Häusser M 《Nature》2007,450(7173):1245-1248
Understanding the transmission of sensory information at individual synaptic connections requires knowledge of the properties of presynaptic terminals and their patterns of firing evoked by sensory stimuli. Such information has been difficult to obtain because of the small size and inaccessibility of nerve terminals in the central nervous system. Here we show, by making direct patch-clamp recordings in vivo from cerebellar mossy fibre boutons-the primary source of synaptic input to the cerebellar cortex-that sensory stimulation can produce bursts of spikes in single boutons at very high instantaneous firing frequencies (more than 700 Hz). We show that the mossy fibre-granule cell synapse exhibits high-fidelity transmission at these frequencies, indicating that the rapid burst of excitatory postsynaptic currents underlying the sensory-evoked response of granule cells can be driven by such a presynaptic spike burst. We also demonstrate that a single mossy fibre can trigger action potential bursts in granule cells in vitro when driven with in vivo firing patterns. These findings suggest that the relay from mossy fibre to granule cell can act in a 'detonator' fashion, such that a single presynaptic afferent may be sufficient to transmit the sensory message. This endows the cerebellar mossy fibre system with remarkable sensitivity and high fidelity in the transmission of sensory information.  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