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1.
Yasuji Fukuda 《Journal of plant research》1982,95(2):183-194
Seedling morphology and vascular course inTribulus terrestris were studied. This species has no erect stem, but four buds appear immediately above the cotyledonary node and grow into prostrate shoots. They were determined to be the main axis of the seedling and the axillary branches of the earliest three foliage leaves, which arise very close to each other. All the leaves, including cotyledons, are vascularized with four bundles among which two are related to a single median gap. When two leaves are attached to one node, lateral traces to the opposed leaves are derived by bifurcation of a single bundle at either side of the stem. In the shoot with a series of alternate leaves, the median pair of traces to every other leaf are found on the same orthostichy. In the branch of which the first node bears no flower but an anisophyllous pair of leaves, the smaller leaf at the node was proven to be the first prophyll because its median traces are superposed by those to the leaf at the next node. 相似文献
2.
Genetic differentiation among eight color types of the freshwater goby,Rhinogobius brunneus, from the western part of Japan was investigated by using electrophoretic methods. Four sympatric types (Cross-band, Dark, Cobalt and Large-Dark (A) types) did not share alleles at between one and six loci out of 12 loci tested. No hybrid specimens were found among these types. The average genetic distances among these four types ranged from 0.13 to 0.72, which fall within the range of values among congeneric species of fishes. The average genetic distances among the other four types, Large-Dark (B), Orange, Shinji-Lake and Boso types, were only 0.01 to 0.03, and fall within the range of values among conspecific populations. These results suggest that the former four types are clearly discrete species and the latter four types may be considered as intraspecific variations of a fifth species. 相似文献
3.
4.
Linolenic acid-[1-14C] was converted to 12-oxo-trans-10-dodecenoic acid, via 12-oxo-cis-9-dodecenoic acid by incubation with chloroplasts of Thea sinensis leaves. Thus, it was confirmed that linolenic acid is split into a C12-oxo-acid, 12-oxo-trans-10-dodecenoic acid, and a C6-aldehyde, trans-2-hexenal, leaf aldehyde, by an enzyme system in chloroplasts of tea leaves. 相似文献
5.
6.
Sawada T Ogawa M Ninomiya R Yokose K Fujiu M Watanabe K Suhara Y Maruyama HB 《Applied and environmental microbiology》1983,45(3):884-891
Thirty-three bacterial strains were isolated from soil, utilizing optically asymmetric degradation of dl-2-hydroxy-4-methylpentanoic acid (dl-HMPA) as the screening probe. Those strains were distributed in the following group and genera: Coryneform and Bacillus, Pseudomonas, and Streptomyces. Among them, the most potent strains, Bacillus freudenreichii NRS-137KH20B and Brevibacterium albidum NRS-130KH20B, could perform the resolution of more than 30 g of dl-HMPA per liter within 4 to 5 days of fermentation. Optically pure l- and d-HMPA enantiomers were obtained in more than 80% theoretical yield, whereas the transformed enantiomer was almost quantitatively recovered as 2-oxo-4-methyl-pentanoic acid in the culture broth. The enantiospecific dehydrogenation responsible for this resolution reaction had a rather wide substrate specificity on straight or branched aliphatic C(4) to C(16) 2-hydroxy acids, exhibiting the optima at chain lengths of either C(7) or C(5), although the enantiospecificity was not changed by chain length. The process was thus successfully extended to the preparation of optically pure C(5) to C(9) 2-hydroxy acids. 相似文献
7.
Identification of a novel amino acid, o-bromo-L-phenylalanine, in egg-associated peptides that activate spermatozoa 总被引:1,自引:0,他引:1
K Yoshino T Takao M Suhara T Kitai H Hori K Nomura M Yamaguchi Y Shimonishi N Suzuki 《Biochemistry》1991,30(25):6203-6209
Eight sperm-activating peptides containing a novel amino acid were isolated from the egg jelly of the sea urchin Tripneustes gratilla. Accurate mass measurement of the peptide in FAB mass spectrometry showed that the mass of the novel amino acid residue was 224.978. On the basis of the isotopic ion distribution and the degree of unsaturation, the mass value indicated that the elemental composition of the amino acid residue was C9H8O1N1Br1, suggesting that the novel amino acid was bromophenylalanine. Proton NMR spectroscopy, amino acid analysis, and RP-HPLC with three synthetic isomers of bromophenylalanine demonstrated that o-bromophenylalanine was the novel amino acid. Derivatization of the amino acid with Marfey's reagent, (1-fluoro-2,4-dinitrophen-5-yl)-L-alanine amide (FDAA), further indicated that the amino acid was the L-isomer. In other sperm-activating peptides isolated from the egg jelly of the sea urchin, both m- and p-bromophenylalanines were discovered. The presence of m-bromophenylalanine has not been previously reported in natural products, while p-bromophenylalanine is found in theonellamide F, an antifungal bicyclic peptide from a marine sponge. 相似文献
8.
Kazuo Ishii Takashi Furuta Yasuji Kasuya 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1996,683(2):225
An HPLC method for determining a flavonoid, naringin, and its metabolite, naringenin, in human plasma is presented for application to the pharmacokinetic study of naringin. Isocratic reversed-phase HPLC was employed for the quantitative analysis by using genistin (for naringin) or daidzein (for naringenin) as an internal standard and solid-phase extraction using a Sep-Pak t C18 cartridge. For the determination, HPLC was carried out using an Inertsil ODS-2 column (250x4.6 m I.D., 5 μm particle size). The mobile phases were acetonitrile-0.1 M ammonium acetate solution (20:80, v/v; pH 7.1) for naringin and acetonitrile-0.1 M ammonium acetate solution-acetic acid (30:69:1, v/v; pH 4.9) for naringenin. The flow-rate was 1 ml min−1. The analyses were performed by monitoring the wavelength of maximum UV absorbance at 280 nm for naringin and at 292 nm for naringenin. The detection limits on-column were about 0.2 ng for the two flavonoids. 相似文献
9.
Kotaro Ito Yoshiki Hanya Yasuji Koyama 《Applied microbiology and biotechnology》2013,97(19):8581-8590
Glutaminase, an enzyme that hydrolyzes l-glutamine to l-glutamate, plays an important role in the production of fermented foods by enhancing the umami taste. In this study, we found ten glutaminase genes in the Aspergillus sojae genome by conducting a BLAST search of the characterized glutaminase sequence. We subsequently constructed glutaminase gene disruptants. The glutaminase activity of the gahB disruptant was decreased by approximately 90 % in A. sojae and Aspergillus oryzae, indicating that this enzyme (GahB) accounted for the majority of the glutaminase activity in Aspergillus species. Subsequently, GahB protein was purified from the AsgahB-overexpressing transformant and characterized. The molecular mass was estimated to be approximately 110 and 259 kDa by SDS-PAGE and gel filtration chromatography, respectively, indicating that the native form of AsGahB was a dimer. The optimal pH was 9.0, and the optimal temperature was 50 °C. Analysis of substrate specificity revealed that AsGahB had peptidoglutaminase-asparaginase activity, similar to AsGahA, but preferred free l-glutamine to free l-asparagine, C-terminal glutaminyl, and asparaginyl residues in peptides. 相似文献
10.
Yasuji Minoda Hisashi Yamagata Tohru Kodama 《Bioscience, biotechnology, and biochemistry》2013,77(7):1829-1830
Strains producing higher levels of cellulolytic enzymes were selected from among 520 strains of plant pathogenic fungi, Fusarium species, and F. oxysporum strain SUF850 was found to be the best producer. When strain SUF850 was cultured using one of three polysaccharides, Avicel, carboxy- methyl cellulose (CMC) or xylan, as a carbon source, the culture filtrate contained degrading activi- ties toward all three substrates, i.e., irrespective of the carbon source used. From the culture filtrate of Avicel-grown cells, four distinct enzymes were purified to homogeneity, as judged on SDS-PAGE. They were designated as CMCase I, CMCase II, /Miitrophenyl-β-d-cellobiosidase and xylanase, and the characteristics of the individual enzymes were examined and compared. 相似文献