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71.
Hayashi K 《Science (New York, N.Y.)》2011,334(6056):593-4; author reply 594-5
72.
Functional brain organization of macaque monkeys and humans was directly compared by functional magnetic resonance imaging. Subjects of both species performed a modified Wisconsin Card Sorting Test that required behavioral flexibility in the form of cognitive set shifting. Equivalent visual stimuli and task sequence were used for the two species. We found transient activation related to cognitive set shifting in focal regions of prefrontal cortex in both monkeys and humans. These functional homologs were located in cytoarchitectonically equivalent regions in the posterior part of ventrolateral prefrontal cortex. This comparative imaging provides insights into the evolution of cognition in primates. 相似文献
73.
Ferguson SM Brasnjo G Hayashi M Wölfel M Collesi C Giovedi S Raimondi A Gong LW Ariel P Paradise S O'toole E Flavell R Cremona O Miesenböck G Ryan TA De Camilli P 《Science (New York, N.Y.)》2007,316(5824):570-574
Dynamin 1 is a neuron-specific guanosine triphosphatase thought to be critically required for the fission reaction of synaptic vesicle endocytosis. Unexpectedly, mice lacking dynamin 1 were able to form functional synapses, even though their postnatal viability was limited. However, during spontaneous network activity, branched, tubular plasma membrane invaginations accumulated, capped by clathrin-coated pits, in synapses of dynamin 1-knockout mice. Synaptic vesicle endocytosis was severely impaired during strong exogenous stimulation but resumed efficiently when the stimulus was terminated. Thus, dynamin 1-independent mechanisms can support limited synaptic vesicle endocytosis, but dynamin 1 is needed during high levels of neuronal activity. 相似文献
74.
Ujihara T Taniguchi F Tanaka J Hayashi N 《Journal of agricultural and food chemistry》2011,59(5):1557-1564
To develop cleaved amplified polymorphic sequence (CAPS) markers for cultivar identification of the tea leaf, 5 primer pairs designed on the basis of genes that encode proteins related to nitrogen assimilation and 26 primer pairs based on expressed sequence tag (EST) sequences of the root of tea plant were screened. From combinations of primer pair and restriction enzyme that showed polymorphism among tea plants, 16 markers were selected and applied to DNA fingerprinting of Japanese tea cultivars. Sixty-three cultivars, except for a bud sport (Kiraka) and its original cultivar (Yabukita) and a pair that was the progeny of the same crossing parent (Harumoegi and Sakimidori), were distinguished from one another. By combining the 16 markers with previously developed CAPS markers and observing the physical appearance, 67 cultivars were distinguishable. The cultivars involve approximately 95% of total tea cultivating area in Japan; therefore, about 95% of tea leaves produced in Japan can be authenticated by labeling their cultivars. 相似文献
75.
Z. Wang T. Maeda M. Hayashi L.-F. Hsiao K.-Y. Liu 《Water, air, and soil pollution》2001,130(1-4):391-396
A nested air quality prediction modeling system (NAQPMS) has been developed to investigate the various processes that govern the loading of chemical species and anthropogenic aerosols at various scales of atmospheric motions in urban and regional scales. The model employs flexible horizontal grid resolution with multiple multi-level nested grids with options for one-way and two-way nesting procedures in a spherical and terrain-following coordinate. The NAQPMS is driven using meteorological fields from the NCAR/Penn State Fifth-Generation Mesoscale Model (MM5). Hourly pollutant levels of 71 stations covering Taiwan are used to evaluate the modeling system. Case simulation of a high-ozone episode occurred during April 13–15 1999 shows that the technique of the model nesting is capable of affording more realistic temporal and spatial structures of concentration fields, processes and precursors. 相似文献
76.
Purification and characterization of polyphenol oxidase from banana (Musa sapientum L.) pulp 总被引:12,自引:0,他引:12
Yang CP Fujita S Ashrafuzzaman M Nakamura N Hayashi N 《Journal of agricultural and food chemistry》2000,48(7):2732-2735
Polyphenol oxidase (EC 1.10.3.1, PPO) in the pulp of banana (Musa sapientum L.) was purified to 636-fold with a recovery of 3.0%, using dopamine as substrate. The purified enzyme exhibited a clear single band on polyacrylamide gel electrophoresis (PAGE) and sodium dodecyl sulfate (SDS)-PAGE. The molecular weight of the enzyme was estimated to be about 41000 and 42000 by gel filtration and SDS-PAGE, respectively. The enzyme quickly oxidized dopamine, and its K(m) value for dopamine was 2.8 mM. The optimum pH was at 6.5, and the enzyme activity was stable in the range of pH 5-11 at 5 degrees C for 48 h. The enzyme had an optimum temperature of 30 degrees C and was stable even after a heat treatment at 70 degrees C for 30 min. The enzyme activity was completely inhibited by L-ascorbic acid, cysteine, sodium diethyldithiocarbamate, and potassium cyanide. Under a low buffer capacity, the enzyme was also strongly inhibited by citric acid and acetic acid at 10 mM. 相似文献
77.
Ikeuchi Y Nakagawa K Endo T Suzuki A Hayashi T Ito T 《Journal of agricultural and food chemistry》2001,49(8):4052-4059
This study was conducted to assess the effect of high hydrostatic pressure on monomer beta-lactoglobulin (BLg) at acid pH by fluorescence spectroscopy under pressure and by circular dichroism (CD) and (1)H NMR spectroscopies after release of pressure. The intrinsic (tryptophan) fluorescence measurement and the study of 8-anilinonaphthalene-1-sulfonate (ANS) binding to BLg indicated that at pH 2.0 the recovery of center of spectral mass or ANS fluorescence was almost complete upon pressure release. No difference in (1)H NMR spectra was observed between pressurized and unpressurized BLg. In addition, NMR detection of the H/D exchange of aromatic protein indicated that the conformation of the vicinity of tryptophan residues could be refolded almost completely after release of pressure. These results seemingly confirm that the pressure-induced denaturation of BLg at pH 2.0 is reversible. However, cis-parinaric acid binding ability of pressurized BLg was largely lost, although its retinol binding ability was the same as its unpressurized one. Furthermore, CD spectra of the far-UV region and 2D NMR spectra evidently revealed the difference in the conformation of the molecule between unpressurized and pressurized BLg. These results are interpreted as an existence of partially fragile structure in the BLg molecule by high pressure. 相似文献
78.
Zhang G Matsumura Y Matsumoto S Hayashi Y Mori T 《Journal of agricultural and food chemistry》2003,51(1):236-243
Two types of transglutaminases (TGases), Ca(2+)-dependent TGase derived from guinea pig liver (GTGase) and Ca(2+)-independent TGase derived from a variant of Streptoverticillium mobaraense (MTGase), were used to study the cross-linking of soybean 11S globulin (glycinin). The effects of sulfhydryl reductant (dithiothreitol, DTT) and Ca(2+) on the conformation and TGase-catalyzed polymerization of glycinin were investigated. The conformational change of glycinin was probed by spectral methods. The degree of cross-linking and the polymer (aggregate) formation were analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and dynamic light scattering, respectively. Addition of DTT stimulated the TGase-catalyzed cross-linking reactions without destroying the secondary and tertiary structure of glycinin but did not influence the polymer or aggregate formation. It was found that Ca(2+) caused the formation of larger size polymers at lower concentrations, while it suppressed the polymerization at higher concentrations. In addition, the cross-linking behaviors of glycinin were shown to be different between MTGase- and GTGase-catalyzed systems. 相似文献
79.
Seiichi Nishimura Kenji Kimiwada Atsushi Yagioka Satoshi Hayashi Norikuni Oka 《Soil Science and Plant Nutrition》2020,66(2):360-368
ABSTRACT Emission of methane (CH4), a major greenhouse gas, from submerged paddy soils is generally reduced by introducing intermittent drainage in summer, which is a common water management in Japan. However, such a practice is not widely conducted in Hokkaido, a northern region in Japan, to prevent a possible reduction in rice grain yield caused by cold weather. Therefore, the effects of intermittent drainage on CH4 emission and rice grain yield have not been investigated comprehensively in Hokkaido. In this study, we conducted a three-year field experiment in Hokkaido and measured CH4 and nitrous oxide (N2O) fluxes and rice grain yield to elucidate whether the reduction in CH4 emission can be achieved in Hokkaido as well as other regions in Japan. Four experimental treatments, namely, two soil types [soils of light clay (LiC) and heavy clay (HC) textures] and two water management [continuous flood irrigation (CF), and intermittent drainage (ID)], were used, and CH4 and N2O fluxes were measured throughout the rice cultivation periods from 2016 to 2018. Cumulative CH4 emissions in 2016 were markedly low, suggesting an initially low population of methanogens in the soils presumably due to no soil submergence or crop cultivation in the preceding years, which indicates a possible reduction in CH4 emission by introducing paddy-upland crop rotation. Cumulative CH4 emissions in the ID-LiC and ID-HC plots were 21–91% lower than those in the CF-LiC and CF-HC plots, respectively, whereas the cumulative N2O emissions did not significantly differ between the different water managements. The amount of CH4 emission reduction by the intermittent drainage was largest in 2018, with a comparatively long period of the first drainage for 12 days in summer. Rice grain yields did not significantly differ between the different water managements for the entire 3 years, although the percentage of well-formed rice grains was reduced by the intermittent drainage in 2018. These results suggest that CH4 emission from paddy fields can be reduced with no decrease in rice grain yield by the intermittent drainage in Hokkaido. In particular, the first drainage for a long period in summer is expected to reduce CH4 emission markedly. 相似文献
80.
T Mizutani M Hayashi A Maeda T Yamashita H Isogai S Namioka 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1992,54(3):465-472
An oligonucleotide complementary to a leader RNA of positive-stranded mouse hepatitis virus (MHV) was tested for the effect on the viral multiplication in mouse DBT cells. A 14-mer antisense oligonucleotide contained a sequence complementary to the conserved pentanucleotide sequence, UCUAA, of the leader RNA. A treatment of MHV-infected cells with the antisense oligonucleotide at concentrations from 5 to 25 microM had an inhibitory effect on the viral multiplication and reduced the synthesis of viral specific mRNA and proteins. No inhibitory effect was observed when the cells were treated with sense oligonucleotide and oligonucleotide which contained unrelated sequences at concentrations from 1 to 10 microM. These results showed that antisense oligonucleotide against the leader RNA reduced the multiplication of positive-stranded RNA virus, MHV. 相似文献