全文获取类型
收费全文 | 349篇 |
免费 | 31篇 |
专业分类
380篇 |
出版年
2021年 | 4篇 |
2019年 | 4篇 |
2018年 | 5篇 |
2017年 | 2篇 |
2016年 | 4篇 |
2015年 | 6篇 |
2014年 | 12篇 |
2013年 | 16篇 |
2012年 | 23篇 |
2011年 | 24篇 |
2010年 | 14篇 |
2009年 | 9篇 |
2008年 | 14篇 |
2007年 | 14篇 |
2006年 | 19篇 |
2005年 | 15篇 |
2004年 | 21篇 |
2003年 | 18篇 |
2002年 | 15篇 |
2001年 | 6篇 |
2000年 | 12篇 |
1999年 | 10篇 |
1998年 | 7篇 |
1997年 | 2篇 |
1996年 | 4篇 |
1995年 | 6篇 |
1994年 | 6篇 |
1993年 | 5篇 |
1992年 | 6篇 |
1991年 | 6篇 |
1990年 | 7篇 |
1989年 | 5篇 |
1988年 | 2篇 |
1986年 | 2篇 |
1985年 | 3篇 |
1984年 | 4篇 |
1983年 | 2篇 |
1981年 | 2篇 |
1980年 | 3篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1976年 | 4篇 |
1975年 | 3篇 |
1974年 | 7篇 |
1973年 | 3篇 |
1972年 | 8篇 |
1971年 | 3篇 |
1969年 | 1篇 |
1968年 | 2篇 |
1967年 | 2篇 |
排序方式: 共有380条查询结果,搜索用时 0 毫秒
371.
372.
Melinda Erzsebet Toth Szilvia Gonda Laszlo Vigh Miklos Santha 《Cell stress & chaperones》2010,15(6):807-817
Alcohol induces degeneration of neurons and inhibits neurogenesis in the brain. Small heat shock proteins are able to protect
neurons in cerebral ischemia and oxidative stress. In this study, we investigated the neuroprotective effect of small heat
shock protein, Hsp27, after acute and chronic ethanol administrations using transgenic mice overexpressing the human Hsp27
protein. Transgenic mice and wild-type littermates were injected with 2 g/kg ethanol intraperitoneally, and then motor coordination
and muscle strength were analyzed using different behavioral tests, such as footprint analysis, balance beam, and inverted
screen tests. Ethanol-injected transgenic mice showed similar footprints to control saline-injected mice, did not fall of
the beam, and were able to climb to the top of the inverted screen, while wild-type mice showed ataxia and incoordination
after ethanol injection. The effect of Hsp27 on chronic ethanol consumption was also investigated. Drinking water of mice
was replaced by a 20% ethanol solution for 5 weeks, and then brain sections were stained with Fluoro Jade C staining. We found
significantly lesser amount of degenerating neurons in the brain of ethanol-drinking transgenic mice compared to wild-type
mice. We conclude that Hsp27 can protect neurons against the acute and chronic toxic effects of ethanol. 相似文献
373.
Directional cloning of native PCR products with preformed sticky ends (Autosticky PCR) 总被引:1,自引:0,他引:1
A novel method for the directional cloning of native PCR products was developed. Abasic sites in DNA templates make DNA polymerases
stall at the site during synthesis of the complementary strand. Since the 5′ ends of PCR product strands contain built-in
amplification primers, abasic sites within the primers result in the formation of 5′ single-stranded overhangs at the ends
of the PCR product, enabling its direct ligation to a suitably cleaved cloning vector without any further modification. This
“autosticky PCR” (AS-PCR) overcomes the problems caused by end sensitivity of restriction enzymes, or internal restriction
sites within the amplified sequences, and enables the generation of essentially any desired 5′ overhang.
Received: 11 August 1998 / Accepted: 2 October 1998 相似文献
374.
The C-terminal cyanogen bromide fragment of VIP, Ala-Val-Lys-Lys-Tyr-Leu-Asn-Ser-Ile-Leu-Asn-NH2 (all l), was synthesized to provide evidence for the correctness of the sequence proposed by Mutt and Said (1). The synthesis of this hendecapeptide (VIP18–28) was carried out by coupling Z-Ala-Val-(Z)Lys to (Z)Lys-Tyr-Leu-Asn-Ser-Ile-Leu-Asn-NH2. After removal of the protecting groups and purification, the synthetic material was indistinguishable from the natural fragment on paper chromatograms and electropherograms. Their identity was further confirmed by comparison of the products formed on enzymatic hydrolysis. 相似文献
375.
We have isolated and sequenced a cDNA from the shaking-B locus of Drosophila melanogaster. The cDNA contains an open reading frame with extensive homology to another D. melanogaster gene, l(1)ogre. This suggests the existence of a new family of proteins required for the development and maintenance of the D. melanogaster nervous system. 相似文献
376.
377.
Localization and quantification of circular DNA in yeast 总被引:33,自引:0,他引:33
378.
George L. Gabor Miklos Hugh D. Campbell 《Current opinion in genetics & development》1992,2(6):902-906
There is an increasingly heated debate on the very existence of a 'universe of exons' and on the types of genomes that existed after the RNA world. What has been lost in the excitement are the biological issues that relate to the rapid emergence of phenotypic novelties. These issues can be examined by integrating data on protein domains and genomic evolution with the geochemical and palaeontological records. 相似文献
379.
Summary Hybrids were constructed between auxotrophic mutants of a heterothallic distiller's strain and a homothallic wine yeast. The hybridization resulted in a significant increase in both ethanol production and tolerance against exogenous ethanol. The hybrids were heterogeneous in ploidy, probably due to segregation of aneuploids during culturing. Sporulation of the hybrids broke down the high productivity, producing spore clones that were mostly of various intermediate levels of performance. However, a meiotic product superior to both crossing partners was also found. The results demonstrate that fermentation capacity can be improved by crossing with a low performance strain.
Offprint requests to: M. Sipiczki 相似文献
380.
Ziegelhöffer Attila Ravingerová Tatiana Džurba Andrej Tribulová Narcisa Slezák Jan Breier Albert Szekeres László 《Molecular and cellular biochemistry》1996,160(1):257-263
It is demonstrated a fast and significant depression in the sarcolemmal (Na,K)-ATPase activity that occurs as early as 25 sec after the onset of Ca2+ depletion, and participates in the development of Ca2+-paradox in the rat heart. Pretreatment of the animals with 7-oxo-prostacyclin (PG12) 24–48 h prior to the experiment prevented fairly the Ca2+-depletion-induced depression in (Na,K)ATPase activity and the accompanying structural and functional damage to the heart and sarcolemma during Ca2+-depletion as well as the development of Ca2+-paradox during the subsequent Ca2+-repletion. Pretreatment with PGI, was chosen intentionally because previous experiments revealed, that in its late effect the drug is acting via stabilizing the membranes due induction of high activity of (Na,K)-ATPase that has increased affinity to ATP. From results obtained the following may be concluded: If during the phase of Ca2+-deprivation, the capability of heart sarcolemma to maintain sodium extrusion remains preserved, the expected aggravation of Ca2+-overload injury to Ca2+-paradox that would develop during Ca2+-repletion, may be definitely prevented. Sufficiently preserved (Na,K)-ATPase activity, hand in hand with stabilized sarcolemmal structure, may prevent an accumulation of sodium beneath the sarcolemma and consequently also an overexcessive entry of Ca2+ into the myocytes. 相似文献