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71.
72.
Takashi Matsumoto Daisuke Yoshida Shigenobu Mizusaki Hideo Tomita Koichi Koshimizu 《Bioscience, biotechnology, and biochemistry》2013,77(4):861-864
The mutagenic activities of quinoline, isoquinoline, phenanthridine, benzo(f)quinoline, benzo(h)quinoline and their α-amino derivatives were compared in relation to the effect of structural changes using the Salmonella typhimurium test system. All mutagenic compounds tested require the liver microsomal fraction for their mutagenic activity. Phenanthridine, two benzoquinolines and quinoline were mutagenic. α-Amination of two benzoquinolines and quinoline resulted to increase their mutagenic activity intensively. Addition of a benzene ring to the benzene moiety of 2-aminoquinoline, so that two carbon atoms are shared, affected distinctly the increase in the mutagenic activity. The co-existence of benzoquinoline series with 2-aminobenzo(f)quinoline showed the clear synergistic action. 相似文献
73.
Atsuko Kushi Akira Koiwai Daisuke Yoshida Fujio Gotō 《Bioscience, biotechnology, and biochemistry》2013,77(10):2513-2515
Mass spectra of N-trifluoroacetyl n-butyl ester (BTFA) of ornithinoalanine (OAL) and lanthionine (LAN) were compared with those of the BTFA derivatives of lysinoalanine (LAL) and the related amino acids. A difference of m/z 14, corresponding to one methylene group, was found in each pair of characteristic fragments between BTFA-OAL and BTFA-LAL. A temperature-programmed gas-liquid chromatography and gas chromatography-mass spectrometry were developed to analyze BTFA-LAN, BTFA-OAL and BTFA-LAL. More LAL and LAN were formed in α-lactalbumin than lysozyme by high-temperature treatment in water. OAL was detected in lysozyme treated at 100° and 120°C in alkali solution, but not in α-lactalbumin. 相似文献
74.
Daisuke Tsuru Heizo Kira Takehiko Yamamoto Juichiro Fukumoto 《Bioscience, biotechnology, and biochemistry》2013,77(9):856-862
The neutral protease of Bacillus amylosacchariticus was inactivated by low concentrations of several metal-chelating agents and the inactivated enzyme with EDTA restored its activity almost completely by the addition of Zn++ or Co++ and partially by Fe++ or Mn++, if these metal ions were added shortly after the EDTA-treatment. The native enzyme was found to contain 0.19% of zinc together with a significant amount of calcium. Parallel increase in specific activity and zinc content of enzyme preparation was observed throughout the purification procedure. The elution pattern of enzyme activity on a CM-cellulose column chromatography also completely coincided with that of protein-bound zinc. A zinc-free inactive enzyme was also reactivated by the addition of zinc or cobalt ions, clearly showing that the neutral protease of B. amylosacchariticus is a zinc mctalloenzyme. 相似文献
75.
Yoshimoto Tadashi Nakanishi Toshihiro Fukumoto Juichiro Tsuru Daisuke 《Bioscience, biotechnology, and biochemistry》2013,77(11):1775-1782
About 100 soil samples were subjected to screening for microorganisms which were capable of producing lytic enzyme toward Staphylococcus aureus. A strain belonging to Streptomyces was isolated and found to produce lytic enzyme(s) noninduciblly, when grown aerobically at 37°C for 25 hr in a medium containing 7.5% soybean cake extract, 2% dextrin, 0.6% K2HPO4, 0.02% each of MgSO4·7H2O and KCl, pH 7.0. The crude enzyme preparation was active at pH values of 8.5 and 5.8 toward S. aureus, B. subtilis, L. bulgaricus and Str. faecalis but was completely inert against M. lysodeikticus, indicating the enzyme(s) to be distinguished from other bacteriolytic enzymes of Streptomyces so far reported. 相似文献
76.
Daisuke Tsuru Heizo Kira Takehiko Yamamoto Juichiro Fukumoto 《Bioscience, biotechnology, and biochemistry》2013,77(3):330-335
Some physicochemical properties and amino acid composition of the alkaline protease of B. amylosacchariticus were determined. The molecular weight and sedimentation coefficient were estimated to be 22,700 and 2.89 s, respectively, and the amino terminal amino acid was identified to be alanine. The enzyme contained 15.9% of nitrogen and was composed of 220 residues of amino acid: lys6, his5, arg3, asp20, thr14, ser37, glu12, pro10, gly25 ala27 val20, met3, isoleu12, leu12, tyr9, phe2, try3 and amide ammonia16 The results indicate that protein nature and chemical properties of the alkaline protease presented here are distinct from those of alkaline proteases obtained from the other strains of B. subtilis, such as subtilopeptidase A, B and BPN’ 相似文献
77.
An arylamidase was purified from Flavobacterium meningosepticum by a series of chromatographies on CM-cellulose, DEAE-Sephadex A-50 and Sephadex G-150. The purified enzyme appeared homogeneous on SDS-gel electrophoresis. The molecular weight of the enzyme was estimated to be more than 500,000 dalton by using a column of Sepharose 4B and to be 62,000 when checked by SDS-gel electrophoresis. The enzyme was most active at pH 7.5 toward Leu-β-naphthylamide (Leu-β-NA). It catalyzed the hydrolysis of not only various amino acid-β-naphthylamides but also some peptides, but the hydrolysis rate of the latter substrates was quite low. Cys-di-β-naphthylamide was split by this enzyme at an optimal pH of 6.2. Incubation of oxytocin with the enzyme resulted in a decrease in the biological activity, indicating that this arylamidase possesses an oxytocinase (cystyl aminopeptidase)-like activity. 相似文献
78.
79.
The Arabidopsis mitogen activated protein kinase kinase kinase (MEKK1) plays an important role in stress signaling. However, little is known about the upstream pathways of MEKK1. This report describes the regulation of MEKK1 activity during cold signaling. Immunoprecipitated MEKK1 from cold-treated Arabidopsis seedlings showed elevated kinase activity towards mitogen activated protein kinase kinase2 (MKK2), one of the candidate MEKK1 substrates. To clarify how MEKK1 becomes active in response to cold stress signaling, MEKK1 phosphorylation was monitored by an enzyme extracted from the seedlings grown under cold stress with or without EGTA. MEKK1 was phosphorylated after cold stress, but EGTA inhibited the phosphorylation. MKK2 was also phosphorylated by the same extract, but only when EGTA was absent. These results suggested that Ca2+ signaling occurred upstream of the MEKK1–MKK2 pathway. Full-length MEKK1 showed almost no activity but MEKK1 without the N-terminal region (MEKK1 KD) that retained the kinase domain had a strong ability to phosphorylate MKK2, demonstrating the inhibitory role of the N-terminal region of MEKK1. In addition, MEKK1 was phosphorylated by calcium/calmodulin-regulated receptor-like kinase (CRLK1), which suggested that CRLK1 is one of candidates located upstream of MEKK1. 相似文献
80.
Noriko Suzuki Daisuke Nawa Tseng-Hsiung Su Chia-Wei Lin Kay-Hooi Khoo Kazuo Yamamoto 《PloS one》2013,8(3)
The Galβ1-4Gal epitope is rarely found in mammals, and the natural antibody against Galβ1-4Gal is rich in human. In contrast, we have previously demonstrated the presence of Galβ1-4Gal in pigeon and ostrich, and the absence of this epitope in chicken. Here, to further investigate the expression of this glycan among birds, egg white glycoproteins and egg yolk IgG from nine species of birds, namely, chicken, duck, emu, guineafowl, ostrich, peafowl, pigeon, quail, and turkey, were analyzed by western blot using an anti-(Galβ1-4Gal) antibody. The results indicated that some egg white glycoproteins from emu, ostrich, and quail, and heavy chains of IgG from all of the birds, except chicken and quail, were stained with the antibody. The presence of Galβ1-4Gal on N-glycans of IgGs from guineafowl, peafowl, and turkey were confirmed by mass spectrometry (MS), MS/MS, and MSn analyses. In quail, the presence of Galβ1-4Gal was confirmed by detecting the activities of UDP-galactose: β-galactoside β1,4-galactosyltransferase (β4GalT(Gal)) in various tissues, and by detecting Galβ1-4Gal by western blotting. In contrast, bamboo partridge, which is a close relative of chicken, did not show any detectable activities of β4GalT(Gal) or Galβ1-4Gal on glycoproteins. Because quail, peafowl, turkey, chicken, and bamboo partridge belong to the same family, i.e., Phasianidae, expression of Galβ1-4Gal was most likely differentiated within this family. Considering that Galβ1-4Gal is also expressed in ostrich, emu, and pigeon, which are phylogenetically distant relatives within modern birds, Galβ1-4Gal expression appears to be widely distributed among birds, but might have been abolished in the ancestors of chicken and bamboo partridge. 相似文献