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81.
82.
Yuko Watanabe Eri Furukawa Hideki Tatsukawa Hisashi Hashimoto Yasuhiro Kamei Yoshihito Taniguchi 《Bioscience, biotechnology, and biochemistry》2018,82(7):1165-1168
Transglutaminase (TG) is an essential enzyme to catalyze cross-linking reactions of epidermal proteins. Recently, we biochemically characterized human skin TG orthologues for medaka (Oryzias latipes), a model fish. By genome editing, gene-modified fishes for the two orthologues were obtained, both of which lack the ordinal enzymes. These fish appeared to exhibit higher susceptibility to osmolality at the period of larvae. 相似文献
83.
Kosuke Nakamoto Yukihiro Akao Yoshihito Ueno 《Bioorganic & medicinal chemistry letters》2018,28(17):2906-2909
We designed and synthesized a photo-reactive and tag-free RNA probe for the identification of microRNA (miRNA) targets. To synthesize the RNA probe, we designed a novel nucleoside analog 1-O-[3-ethynyl-5-(3-trifluoromethyl-3H-diazirine-3-yl)]benzyl-β-d-ribofuranose containing aryl trifluoromethyl diazirine and ethynyl moieties. The RNA probe containing this analog was observed to form crosslinks with complementary RNA by UV irradiation and was rapidly tagged by Cu-catalyzed azide alkyne cycloaddition (CuAAC). In addition, the tag-free and photo-reactive miRNA-145 probe showed comparable gene silencing activity to that of unmodified miRNA-145. Therefore, miRNA probes containing the nucleoside analog are promising candidates for the identification of target mRNAs of miRNAs. 相似文献
84.
Masayuki Nakanishi Akihiro Yoshimura Norihisa Ishida Yoshihito Ueno Yukio Kitade 《European journal of biochemistry》2004,271(13):2737-2744
Ribonuclease L (RNase L) is a key enzyme in the 2-5A host defense system, and its activity is strictly regulated by an unusual 2',5'-linked oligoadenylate (2-5A). A bipartite model, in which the N-terminal half of RNase L is responsible for the 2-5A binding and the C-terminal half alone is able to hydrolyse the substrate RNA, has been proposed on the basis of the results of deletion mutant analyses [Dong, B. & Silverman, R.H. (1997) J. Biol. Chem.272, 22236-22242]. Above all, the region between Glu711 and His720 was revealed to be essential for RNA binding and/or hydrolysis. To dissect the function of the region, we performed scanning mutagenesis over the 10 residues of glutathione S-transferase (GST)-fusion RNase L. Among the single amino acid mutants examined, Y712A and F716A resulted in a significant decrease of RNase activity with a reduced RNA binding acitivity. The losses of the RNase activity were not restored by its conservative mutation, whereas the RNA binding activity was enhanced in the case of Y712F. These results indicate that both Tyr712 and Phe716 provide the enzyme with a RNA binding activity and catalytic environment. 相似文献
85.
Tomohiko Matsuzawa Yasushi Mitsuishi Akihiko Kameyama Katsuro Yaoi 《The Journal of biological chemistry》2016,291(10):5080-5087
Aspergillus oryzae produces a unique β-glucosidase, isoprimeverose-producing oligoxyloglucan hydrolase (IPase), that recognizes and releases isoprimeverose (α-d-xylopyranose-(1→6)-d-glucopyranose) units from the non-reducing ends of oligoxyloglucans. A gene encoding A. oryzae IPase, termed ipeA, was identified and expressed in Pichia pastoris. With the exception of cellobiose, IpeA hydrolyzes a variety of oligoxyloglucans and is a member of the glycoside hydrolase family 3. Xylopyranosyl branching at the non-reducing ends was vital for IPase activity, and galactosylation at a α-1,6-linked xylopyranosyl side chain completely abolished IpeA activity. Hepta-oligoxyloglucan saccharide (Xyl3Glc4) substrate was preferred over tri- (Xyl1Glc2) and tetra- (Xyl2Glc2) oligoxyloglucan saccharides substrates. IpeA transferred isoprimeverose units to other saccharides, indicating transglycosylation activity. The ipeA gene was expressed in xylose and xyloglucan media and was strongly induced in the presence of xyloglucan endo-xyloglucanase-hydrolyzed products. This is the first study to report the identification of a gene encoding IPase in eukaryotes. 相似文献
86.
Ayaka Shinkawa Katsuro Yaoi Tomoyuki Kadotani Morikazu Imamura Nobuo Koizumi Hidenori Iwahana Ryoichi Sato 《Current microbiology》1999,39(1):14-20
We investigated the binding proteins for three Cry toxins, Cry1Aa, Cry1Ac, and the phylogenetically distant Cry9Da, in the
midgut cell membrane of the silkworm. In a ligand blot experiment, Cry1Ac and Cry9Da bound to the same 120-kDa aminopeptidase
N (APN) as Cry1Aa. A competition experiment with the ligand blot indicated that the three toxins share the same binding site
on several proteins. The values of the dissociation constants of the three Cry toxins and 120-kDa APN are as low as the case
of other Cry toxins and receptors. These results suggest that distantly related Cry toxins bind to the same site on the same
proteins, especially with APN. We propose that the conserved structure in these three toxins includes the receptor-binding
site.
Received: 12 January 1998 / Accepted: 17 February 1999 相似文献
87.
Kiichiro Teruya Yoshihito Daimon Xiao-Yan Dong Yoshinori Katakura Takumi Miura Akira Ichikawa Tsukasa Fujiki Makiko Yamashita Tetsuya Mori Hideya Ohashi Sanetaka Shirahata 《Cytotechnology》2005,47(1-3):29-36
The cell line D29, which was easily and rapidly established by the promoter-activated production and glutamine synthetase
hybrid system, secreted recombinant human interleukin-6 (hIL-6) at a productivity rate of 39.5 μg 10−6 cells day−1, one of the highest reported levels worldwide. The productivity rate was about 130-fold higher than that of the cell line
A7, which was established without both promoter activation and gene amplification. Although D29 cells had a high copy number
and high mRNA level of the hIL-6 gene as well as a high secretion rate of hIL-6, large amounts of intracellular hIL-6 protein
accumulated in D29 cells compared to A7 cells. Northern blotting analysis showed no change in the GRP78/BiP expression level
in D29 cells. In contrast, an electrophoresis mobility shift assay revealed strong activation of NF-κB in D29 cells. These
results suggest that large amounts of hIL-6 translated from large amounts of hIL-6 mRNA cause excess accumulation of intact
hIL-6 in the endoplasmic reticulum (ER), and that subsequent negative feedback signals via the ER overload response inhibit
hIL-6 protein secretion. To enhance the hIL-6 productivity rate of D29 cells by releasing the negative feedback signals, the
effect of pyrrolidinedithiocarbamate, an inhibitor of NF-κB activation, was examined. Suppression of NF-κB activation in D29
cells produced a 25% augmentation of the hIL-6 productivity rate. Therefore, in highly productive cells like D29 cells, the
release of negative feedback signals could increase the total amount of recombinant protein secretion. 相似文献
88.
Shiono Y Shimanuki K Hiramatsu F Koseki T Tetsuya M Fujisawa N Kimura K 《Bioorganic & medicinal chemistry letters》2008,18(23):6050-6053
Pyrrospirones A and B have been isolated from unpolished rice cultures of the endophytic fungus Neonectria ramulariae Wollenw KS-246. Their absolute stereostructures (1 and 2) were elucidated through spectroscopic methods using 1D and 2D NMR techniques and chemical transformations, including the modified Mosher's method. The compounds exhibited cytotoxicity and induced apoptosis in human promyelocytic leukemia HL-60 cells. 相似文献
89.
Takuya Koseki Akane Hori Shouji Seki Tetsuya Murayama Yoshihito Shiono 《Applied microbiology and biotechnology》2009,83(4):689-696
Two hypothetical proteins XP_001818628 and XP_001819091 (designated AoFaeB and AoFaeC, respectively), showing sequence identity
with known type-C feruloyl esterases, have been found in the genomic sequence of Aspergillus oryzae. We cloned the putative A. oryzae feruloyl esterase-encoding genes and expressed them in Pichia pastoris. Both purified recombinant AoFaeB (rAoFaeB) and AoFaeC (rAoFaeC) had apparent relative molecular masses of 61,000 and 75,000,
respectively, on sodium dodecyl sulfate-polyacrylamide gel electrophoresis. After N-deglycosylation, both proteins had a relative molecular mass of 55,000. The optimum pH for rAoFaeB was 6.0, although it was
stable at pH values ranging from 3.0 to 9.0; rAoFaeC had an optimum pH of 6.0 and was stable in the pH range of 7.0–10.0.
Thermostability of rAoFaeC was greater than that of rAoFaeB. Whereas rAoFaeC displayed hydrolytic activity toward methyl caffeate,
methyl p-coumarate, methyl ferulate, and methyl sinapate, rAoFaeB displayed hydrolytic activity toward methyl caffeate, methyl p-coumarate, and methyl ferulate but not toward methyl sinapate. Substrate specificity profiling of rAoFaeB and rAoFaeC revealed
type-B and type-C feruloyl esterases, respectively. Ferulic acid was efficiently released from wheat arabinoxylan when both
esterases were applied with xylanase from Thermomyces lanuginosus. Both recombinant proteins also exhibited hydrolytic activity toward chlorogenic acid.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
90.
The application of the mutated acetolactate synthase gene from rice as the selectable marker gene in the production of transgenic soybeans 总被引:1,自引:0,他引:1
Makoto Tougou Noriko Yamagishi Noriyuki Furutani Koichiro Kaku Tsutomu Shimizu Yoshihito Takahata Jun-ichi Sakai Seiji Kanematsu Soh Hidaka 《Plant cell reports》2009,28(5):769-776
We investigated selective culturing conditions for the production of transgenic soybeans. In this culturing system, we used
the acetolactate synthase (ALS)-inhibiting herbicide-resistance gene derived from rice (Os-mALS gene) as a selectable marker gene instead of that derived from bacteria, which interfered with the cultivation and practical
usage of transgenic crops. T1 soybeans grown from one regenerated plant after selection of the ALS-targeting pyrimidinyl carboxy (PC) herbicide bispyribac-sodium
(BS) exhibited herbicide resistance, and the introduction and expression of the Os-mALS gene were confirmed by genetic analysis. The selective culturing system promoted by BS herbicide, in which the Os-mALS gene was used as a selectable marker, was proved to be applicable to the production of transgenic soybeans, despite the appearance
of escaped soybean plants that did not contain the Os-mALS transgene. 相似文献