全文获取类型
收费全文 | 194篇 |
免费 | 8篇 |
专业分类
202篇 |
出版年
2023年 | 1篇 |
2022年 | 1篇 |
2021年 | 1篇 |
2019年 | 1篇 |
2018年 | 2篇 |
2016年 | 1篇 |
2015年 | 1篇 |
2014年 | 3篇 |
2013年 | 36篇 |
2012年 | 6篇 |
2011年 | 11篇 |
2010年 | 3篇 |
2009年 | 6篇 |
2008年 | 16篇 |
2007年 | 12篇 |
2006年 | 11篇 |
2005年 | 18篇 |
2004年 | 10篇 |
2003年 | 16篇 |
2002年 | 10篇 |
2000年 | 1篇 |
1999年 | 2篇 |
1995年 | 2篇 |
1993年 | 1篇 |
1992年 | 1篇 |
1991年 | 1篇 |
1989年 | 3篇 |
1988年 | 1篇 |
1985年 | 1篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 4篇 |
1981年 | 2篇 |
1978年 | 4篇 |
1977年 | 3篇 |
1976年 | 3篇 |
1975年 | 1篇 |
1974年 | 1篇 |
1973年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有202条查询结果,搜索用时 0 毫秒
61.
Tadahiko Kajiwara Takahiro Harada Akikazu Hatanaka 《Bioscience, biotechnology, and biochemistry》2013,77(1):243-247
Z-3-Hexenal, a precursor in the biosynthesis of leaf alcohol and leaf aldehyde, was first isolated from fresh tea leaves, Thea sinensis and its structure was confirmed by unequivocal synthetic evidence. 相似文献
62.
Direct tissue matrix-assisted laser desorption ionization with time-of-flight mass spectrometry analysis provides a selective detection of mass profile for the peptides contained into cell secretory granules. By this mass spectrometry with slice of pituitary, two novel molecular forms of pro-opimelanocrtin related hormone were found in the orange-red strain medaka (Oryzias latipes var.). The structures of [N,O-diacetyl Serine1, O-acetyl Serine3]-α-melanocyte-stimulating hormone (MSH) and [hydroxyproline15]-β-MSH, together with [phosphoserine15]-corticotropin-like intermediate lobe peptide, were determined for the first time using a collision-induced dissociation with electrospray ionization mass spectrometry. A combination of mass spectrometry analyses is thus a powerful tool to lead to the elucidation of the post-translational processing from the pre-prohormone. 相似文献
63.
Nishimura T Sakudo A Hashiyama Y Yachi A Saeki K Matsumoto Y Ogawa M Sakaguchi S Itohara S Onodera T 《Microbiology and immunology》2007,51(4):457-466
Previous studies have shown that cellular prion protein (PrP(C)) plays anti-apoptotic and antioxidative role against cell death induced by serum-deprivation (SDP) in an immortalized prion protein gene-deficient neuronal cell line derived from Rikn prion protein (PrP) gene-deficient (Prnp(-/-)) mice, which ectopically produce excess Doppel (Dpl) (PrP-like glycoprotein). To investigate whether PrP(C) inhibits apoptotic neuronal cell death without Dpl, an immortalized cell line was established from the brain of ZrchI Prnp(-/-) mice, which do not show ectopic expression of Dpl. The results using a ZrchI neuronal Prnp(-/-) cell line (NpL2) showed that PrP(C) potently inhibited SDP-induced apoptotic cell death. Furthermore, PrP(C) expression enhanced the superoxide dismutase (SOD) activity in NpL2 cells. These results indicate that Dpl production did not affect anti-apoptotic and anti-oxidative functions of PrP, suggesting that PrP(C) may be directly correlated with protection against oxidative stress. 相似文献
64.
The enzyme activity responsible for volatile C6-aldehyde formation was accompanied by lipoxygenase and hydroperoxide lyase in the green leaves of 28 plant species tested, but the level of each enzyme's activity varied. Lipoxygenase activity rather than hydroperoxide lyase activity appears to affect the overall C6-aldehyde formation. There was a positive correlation (r = 0.712) between hydroperoxide lyase activity and the chlorophyll content of the green leaves; no correlation was found between lipoxygenase activity and chlorophyll content. 相似文献
65.
66.
Ascospores ofAleuria aurantia did not germinate soon after collection. The treatment with alkali induced germination, but the rate was less than 0.01%.
After storage of the ascospore at 4°C or at −20°C for three mo, germination was enhanced, and its rate was approximately 60%. 相似文献
67.
68.
Mukai K Takeuchi T Toyoshima M Satoh Y Fujita A Shintani N Hashimoto H Baba A Hata F 《Regulatory peptides》2006,133(1-3):54-61
Mediators of neurogenic responses of the gastric fundus were studied in wild type and pituitary adenylate cyclase activating peptide (PACAP) knockout mice. Electrical field stimulation (EFS) to the circular muscle strips of the wild type mouse fundus induced a tri-phasic response, rapid transient contraction and relaxation, and sustained relaxation that was prolonged for an extended period after the end of EFS. The transient relaxation and contraction were completely inhibited by N(G)-nitro-L-arginine and atropine, respectively. The sustained relaxation was completely inhibited by a PACAP receptors antagonist, PACAP(6-38). The strips prepared from PACAP knockout mice exhibited a large contraction without rapid relaxation and unexpectedly, a sustained relaxation. However, the sustained relaxation was decreased to about a half of that observed in wild type mice. Anti-peptide histidine isoleucine (PHI) serum abolished the sustained relaxation in the knockout mice. The serum partially inhibited the sustained relaxation in wild type mice and PACAP(6-38) abolished the relaxation that remained after the antiserum-treatment. PHI relaxed the strips prepared from wild type mice. The relaxation was completely inhibited by PACAP(6-38). It was concluded that PACAP and PHI separately mediate the sustained relaxation in the mouse gastric fundus, and that nitric oxide and ACh mediate transient relaxation and contraction, respectively. 相似文献
69.
Ando A Saito A Arai S Usuda S Furuno M Kaneko N Shida O Nagata Y 《Bioscience, biotechnology, and biochemistry》2008,72(8):2074-2081
Pseudomonas sp. A-01, isolated as a strain with chitosan-degrading activity, produced a 28 kDa chitosanase. Following purification of the chitosanase (Cto1) and determination of its N-terminal amino acid sequence, the corresponding gene (cto1) was cloned by a reverse-genetic technique. The gene encoded a protein, composed of 266 amino acids, including a putative signal sequence (1-28), that showed an amino acid sequence similar to known family-46 chitosanases. Cto1 was successfully overproduced and was secreted by a Brevibacillus choshinensis transformant carrying the cto1 gene on expression plasmid vector pNCMO2. The purified recombinant Cto1 protein was stable at pH 5-8 and showed the best chitosan-hydrolyzing activity at pH 5. Replacement of two acidic amino acid residues, Glu23 and Asp41, which correspond to previously identified active centers in Streptomyces sp. N174 chitosanase, with Gln and Asn respectively caused a defect in the hydrolyzing activity of the enzyme. 相似文献
70.
Jinglei Cheng Akikazu Fujita Yuki Ohsaki Michitaka Suzuki Yuki Shinohara Toyoshi Fujimoto 《Histochemistry and cell biology》2009,132(3):281-291
The lipid droplet (LD) is an organelle with a lipid ester core and a surface phospholipid monolayer. The mechanism of LD biogenesis
is not well understood. The present study aimed to elucidate the LD growth process, for which we developed a new electron
microscopic method that quantifies the proportion of existing and newly synthesized triglycerides in individual LDs. Our method
takes advantage of the reactivity of unsaturated fatty acids and osmium tetroxide, which imparts LDs an electron density that
reflects fatty acid composition. With this method, existing triglyceride-rich LDs in 3Y1 fibroblasts were observed to incorporate
newly synthesized triglycerides at a highly uniform rate. This uniformity and its persistence even after microtubules were
depolymerized suggest that triglycerides in fibroblasts are synthesized in the local vicinity of individual LDs and then incorporated.
In contrast, LDs in 3T3-L1 adipocytes showed heterogeneity in the rate at which lipid esters were incorporated, indicating
different mechanisms of LD growth in fibroblasts and adipocytes. 相似文献