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排序方式: 共有390条查询结果,搜索用时 22 毫秒
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Takahashi Jun Kanbayashi Takashi Ito Uemura Sachiko Sagawa Youhei Tsutsui Kou Takahashi Yuya Omori Yuki Imanishi Aya Takeshima Masahiro Satake Masahiro Shimizu Tetsuo 《Sleep and biological rhythms》2017,15(3):235-241
Sleep and Biological Rhythms - Next-day residual effects are a common problem with current hypnotics. The purpose of the present study was to evaluate the residual effects of eszopiclone on the... 相似文献
303.
Yosuke Inoue Yuya Hanazono Kentaro Noi Akihiro Kawamoto Masato Kimatsuka Ryuhei Harada Kazuki Takeda Ryoichi Kita Natsuki Iwamasa Kyoka Shibata Keiichi Noguchi Yasuteru Shigeta Keiichi Namba Teru Ogura Kunio Miki Kyosuke Shinohara Masafumi Yohda 《Structure (London, England : 1993)》2021,29(7):721-730.e6
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Panneerselvam Krishnamurthy Yuya Takahashi Yuji Hongo Ram J. Singh Jeong Dong Lee 《Bioscience, biotechnology, and biochemistry》2013,77(12):1988-1996
Eight wild soybean accessions with different saponin phenotypes were used to examine saponin composition and relative saponin quantity in various tissues of mature seeds and two-week-old seedlings by LC–PDA/MS/MS. Saponin composition and content were varied according to tissues and accessions. The average total saponin concentration in 1?g mature dry seeds of wild soybean was 16.08?±?3.13?μmol. In two-week-old seedlings, produced from 1?g mature seeds, it was 27.94?±?6.52?μmol. Group A saponins were highly concentrated in seed hypocotyl (4.04?±?0.71?μmol). High concentration of DDMP saponins (7.37?±?5.22?μmol) and Sg-6 saponins (2.19?±?0.59?μmol) was found in cotyledonary leaf. In seedlings, the amounts of group A and Sg-6 saponins reduced 2.3- and 1.3-folds, respectively, while DDMP?+?B?+?E saponins increased 2.5-fold than those of mature seeds. Our findings show that the group A and Sg-6 saponins in mature seeds were degraded and/or translocated by germination whereas DDMP saponins were newly synthesized. 相似文献
306.
Hippocampal function is important in the acquisition of negative patterning but not of simple discrimination. This study examined rat hippocampal theta activity during the acquisition stages (early, middle, and late) of the negative patterning task (A+, B+, AB-). The results showed that hippocampal theta activity began to decline transiently (for 500 ms after non-reinforced stimulus presentation) during the late stage of learning in the negative patterning task. In addition, this transient decline in hippocampal theta activity in the late stage was lower in the negative patterning task than in the simple discrimination task. This transient decline during the late stage of task acquisition may be related to a learning process distinctive of the negative patterning task but not the simple discrimination task. We propose that the transient decline of hippocampal theta activity reflects inhibitory learning and/or response inhibition after the presentation of a compound stimulus specific to the negative patterning task. 相似文献
307.
Kaori Tsujino Yuya Okuzaki Nobuyuki Hibino Kazuki Kawamura Seiji Saito Yumi Ozaki Satoshi Ishishita Atsushi Kuroiwa Shinji Iijima Yoichi Matsuda Kenichi Nishijima Takayuki Suzuki 《Development, growth & differentiation》2019,61(7-8):393-401
Transgenic birds are commonly used for time-lapse imaging and fate mapping studies in developmental biology. When researchers use transgenic birds expressing fluorescent protein, they need to understand the integration site of the transgene in the genome and the intensity of fluorescence in the tissues of interest. In this study, we determined the integration site of the transgene and fluorescence property of developing organs in our transgenic chicken line generated by lentivirus infection. The transgene was localized between exons 3 and 4 of MED27. Some homozygotes and heterozygotes appeared to be lethal at early embryonic stages. We performed histological analysis of EGFP expression in transgenic embryos at St. 14, 17, and 24 by immunohistochemistry with anti-GFP antibody on paraffin sections. Next, we cut cryosections and quantified direct EGFP intensity from the transgene in each tissue without performing immunohistochemistry. These results revealed that EGFP intensity in each tissue was unique in developing embryos and changed according to developmental stages. Finally, we demonstrated that EGFP-expressing cells in a micromass culture with co-culturing wild-type cells were clearly distinguishable via live cell imaging. These results provide essential information on the potential of our transgenic line and indicate that these transgenic chicken lines are useful for research associated with developmental biology. 相似文献
308.
Sublancin is an S‐linked glycopeptide produced by Bacillus subtilis 168 and consists of 37 amino acid residues with two disulfide bonds. In this study, we synthesized sublancin by Fmoc‐based solid‐phase peptide synthesis and chemoselective disulfide formation reactions. Copyright © 2011 European Peptide Society and John Wiley & Sons, Ltd. 相似文献
309.
Yoneda K Kawakami R Tagashira Y Sakuraba H Goda S Ohshima T 《Biochimica et biophysica acta》2006,1764(6):1087-1093
A gene encoding an L-aspartate dehydrogenase (EC 1.4.1.21) homologue was identified in the anaerobic hyperthermophilic archaeon Archaeoglobus fulgidus. After expression in Escherichia coli, the gene product was purified to homogeneity, yielding a homodimeric protein with a molecular mass of about 48 kDa. Characterization revealed the enzyme to be a highly thermostable L-aspartate dehydrogenase, showing little loss of activity following incubation for 1 h at up to 80 degrees C. The optimum temperature for L-aspartate dehydrogenation was about 80 degrees C. The enzyme specifically utilized L-aspartate as the electron donor, while either NAD or NADP could serve as the electron acceptor. The Km values for L-aspartate were 0.19 and 4.3 mM when NAD or NADP, respectively, served as the electron acceptor. The Km values for NAD and NADP were 0.11 and 0.32 mM, respectively. For reductive amination, the Km values for oxaloacetate, NADH and ammonia were 1.2, 0.014 and 167 mM, respectively. The enzyme showed pro-R (A-type) stereospecificity for hydrogen transfer from the C4 position of the nicotinamide moiety of NADH. This is the first report of an archaeal L-aspartate dehydrogenase. Within the archaeal domain, homologues of this enzyme occurred in many Methanogenic species, but not in Thermococcales or Sulfolobales species. 相似文献
310.
Isaji T Sato Y Zhao Y Miyoshi E Wada Y Taniguchi N Gu J 《The Journal of biological chemistry》2006,281(44):33258-33267
The N-glycosylation of integrin alpha5beta1 is thought to play crucial roles in cell spreading, cell migration, ligand binding, and dimer formation, but the underlying mechanism remains unclear. To investigate the importance of the N-glycans of this integrin in detail, sequential site-directed mutagenesis was carried out to remove single or combined putative N-glycosylation sites on the alpha5 integrin. Removal of the putative N-glycosylation sites on the beta-propeller, Thigh, Calf-1, or Calf-2 domains of the alpha5 subunit resulted in a decrease in molecular weight compared with the wild type, suggesting that all of these domains contain attached N-glycans. Importantly, the absence of N-glycosylation sites (sites 1-5) on the beta-propeller resulted in the persistent association of integrin subunit with calnexin in the endoplasmic reticulum, which subsequently blocked heterodimerization and its expression on the cell surface. Interestingly, the activities for cell spreading and migration for the alpha5 subunit carrying only three potential N-glycosylation sites (3-5 sites) on the beta-propeller were comparable with those of the wild type. In contrast, mutation of these three sites resulted in a significant decrease in cell spreading as well as functional expression, although the total expression level of the Delta3-5 mutant on the cell surface was comparable with that of wild type. Furthermore, we found that site 5 is a most important site for its expression on the cell surface, whereas the S5 mutant did not show any biological functions. Taken together, this study reveals for the first time that the N-glycosylation on the beta-propeller domain of the alpha5 subunit is essential for heterodimerization and biological functions of alpha5beta1 integrin and might also be useful for studies of the molecular structure. 相似文献