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81.
K. Yamamoto Y. Tsuji Y. Aso T. Hamasaki S. Shirahata Y. Katakura 《Journal of Applied Entomology》2011,135(4):320-325
We investigated the effects of exposure to diazinon, an organophosphate insecticide, on the expression of antioxidant and detoxification factors in the silkmoth. Exposure to diazinon resulted in induction of mRNA encoding manganese containing superoxide dismutase (SOD) and omega‐class glutathione S‐transferases (GST), whereas no changes were observed in catalase, other class of GST and acetylcholinesterase. Liquid chromatography showed that the amount of reactive oxygen species was increased, whereas the amount of glutathione was decreased in the silkmoth fat body after exposure to diazinon. These results suggest that SOD and omega‐class GSTs can contribute to organophosphate resistance in Lepidopterans. 相似文献
82.
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84.
Short communication. Biomass and production of cyanobacteria in a coastal water of Sagami Bay, Japan
Hamasaki K; Satoh F; Kikuchi T; Toda T; Taguchi S 《Journal of plankton research》1999,21(8):1583-1591
Cyanobacteria were relatively small contributors to carbon biomass
(097-18%) in the euphotic zone. However, a higher contribution to
production obtained at the surface water (16-45%) implies that they
contribute more to carbon cycling than is expected from their biomass
相似文献
85.
Enzymatic Formation of G-Group Aflatoxins and Biosynthetic Relationship between G- and B-Group Aflatoxins 总被引:6,自引:3,他引:3
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We detected biosynthetic activity for aflatoxins G1 and G2 in cell extracts of Aspergillus parasiticus NIAH-26. We found that in the presence of NADPH, aflatoxins G1 and G2 were produced from O-methylsterigmatocystin and dihydro-O-methylsterigmatocystin, respectively. No G-group aflatoxins were produced from aflatoxin B1, aflatoxin B2, 5-methoxysterigmatocystin, dimethoxysterigmatocystin, or sterigmatin, confirming that B-group aflatoxins are not the precursors of G-group aflatoxins and that G- and B-group aflatoxins are independently produced from the same substrates (O-methylsterigmatocystin and dihydro-O-methylsterigmatocystin). In competition experiments in which the cell-free system was used, formation of aflatoxin G2 from dihydro-O-methylsterigmatocystin was suppressed when O-methylsterigmatocystin was added to the reaction mixture, whereas aflatoxin G1 was newly formed. This result indicates that the same enzymes can catalyze the formation of aflatoxins G1 and G2. Inhibition of G-group aflatoxin formation by methyrapone, SKF-525A, or imidazole indicated that a cytochrome P-450 monooxygenase may be involved in the formation of G-group aflatoxins. Both the microsome fraction and a cytosol protein with a native mass of 220 kDa were necessary for the formation of G-group aflatoxins. Due to instability of the microsome fraction, G-group aflatoxin formation was less stable than B-group aflatoxin formation. The ordA gene product, which may catalyze the formation of B-group aflatoxins, also may be required for G-group aflatoxin biosynthesis. We concluded that at least three reactions, catalyzed by the ordA gene product, an unstable microsome enzyme, and a 220-kDa cytosol protein, are involved in the enzymatic formation of G-group aflatoxins from either O-methylsterigmatocystin or dihydro-O-methylsterigmatocystin. 相似文献
86.
Cell Surface Galactosylation Is Essential for Nonsexual Flocculation in Schizosaccharomyces pombe
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Naotaka Tanaka Atsuro Awai M. Shah Alam Bhuiyan Kiyotaka Fujita Hiroshi Fukui Kaoru Takegawa 《Journal of bacteriology》1999,181(4):1356-1359
We have isolated fission yeast mutants that constitutively flocculate upon growth in liquid media. One of these mutants, the gsf1 mutant, was found to cause dominant, nonsexual, and calcium-dependent aggregation of cells into flocs. Its flocculation was inhibited by the addition of galactose but was not affected by the addition of mannose or glucose, unlike Saccharomyces cerevisiae FLO mutants. The gsf1 mutant coflocculated with Schizosaccharomyces pombe wild-type cells, while no coflocculation was found with galactose-deficient (gms1Δ) cells. Moreover, flocculation of the gsf1 mutant was also inhibited by addition of cell wall galactomannan from wild-type cells but not from gms1Δ cells. These results suggested that galactose residues in the cell wall glycoproteins may be receptors of gsf1-mediated flocculation, and therefore cell surface galactosylation is required for nonsexual flocculation in S. pombe. 相似文献
87.
88.
A multispecific monoclonal antibody G2 recognizes at least three completely different epitope sequences with high affinity
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Md. Nuruddin Mahmud Masayuki Oda Daiki Usui Yasuo Inoshima Naotaka Ishiguro Yuji O. Kamatari 《Protein science : a publication of the Protein Society》2017,26(11):2162-2169
A monoclonal antibody (mAb) G2 possesses an unusual characteristic of reacting with at least three proteins (ATP6V1C1, SEPT3, and C6H10orf76) other than its original antigen, chicken prion protein (ChPrP). The epitopes on ChPrP and ATP6V1C1 have been identified previously. In this study, we identified the epitope in the third protein, SEPT3. Interestingly, there was no amino acid sequence similarity among the epitopes on the three proteins. These epitopes had high binding affinities to G2 (K D = ~10?7 M for monovalent binding and K D = ~10?9 M for divalent binding), as determined using a SPR biosensor. This is the first report on a three‐in‐one mAb recognizing completely different epitope sequences with high affinity. Additionally, competitive ELISA indicated that the binding sites on G2, specific for the three different epitopes, overlapped, suggesting that the antigen‐binding site may be flexible in the free form and capable of adapting to at least three different conformations to enable interactions with three different antigens. 相似文献
89.
Phenolic and iridoid glycosides from Strychnos axillaris 总被引:1,自引:0,他引:1
Five phenolic glycosides 1-5 and an iridoid glucoside 6 were isolated, together with 22 known compounds, from the dried barks and woods of Strychnosaxillaris. Their structures were determined by application of spectroscopic (NMR, MS) and chemical methodologies. 相似文献
90.
Sein Lwin Yasuo Inoshima Hiroshi Ueno Naotaka Ishiguro 《Cell and tissue research》2009,337(1):125-135
To investigate the uptake and transport patterns of variously sized particles in Peyer’s patches (PPs) of calves, intestinal
loops were created in four newborn and two 2-month-old calves, and the loops were inoculated with various particles, including
carbon black, fluorescein isothiocyanate (FITC)-labeled latex, FITC-labeled dextran, bovine serum, and recombinant mouse prion
protein (rMPrP). The intestinal loops were recovered at 3, 6, 9, and 24 h in newborn calves and at 24 h in 2-month-old calves
after inoculation, and the transport of the particles was examined by histological and immunohistochemical means. The uptake
of the particles was quantified by estimation of signal intensities. A greater intensity was found in newborn calves compared
with the 2-month-old calves. The peak uptake of carbon black, FITC-labeled latex, and rMPrP in the PPs of the distal ileum
occurred at 6 h after inoculation in newborn calves and then progressively decreased with time. Uptake was also dependent
on the site within the small intestine and the size of the particle studied. The transport of carbon black, FITC-labeled latex,
and FITC-labeled dextran occurred via the bloodstream, the mesenteric lymph nodes, and the liver of newborn calves. rMPrP
was found primarily in the interfollicular regions of the submucosa of the distal ileum of newborn calves. Thus, distal ileal
PPs are probably more effective at particle absorption than the jejunal PPs, and the peak uptake of the PPs within the newborn
calf occurs at 6 h after inoculation.
This study was partly supported by a grant for BSE research from the Ministry of Health, Labour, and Welfare, Japan (17270701)
and Grant-in-Aid (no. 17380180) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan. 相似文献