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41.
Effect of shrimp head protein hydrolysates on the state of water and denaturation of fish myofibrils during dehydration 总被引:1,自引:0,他引:1
Yaowalux?Ruttanapornvareesakul Misako?Ikeda Kenji?HaraEmail author Kazufumi?Osako Orawan?Kongpun Yukinori?Nozaki 《Fisheries Science》2005,71(1):220-228
ABSTRACT: To utilize fisheries waste products as food materials with functional properties, shrimp head protein hydrolysates (SHPH) from three species of shrimp, that is, Northern pink shrimp ( Pandalus eous ), Endeavour shrimp ( Metapenaeus endeavouri ) and Black tiger shrimp ( Penaeus monodon ), were produced by enzymatic hydrolysis using endopeptidase derived from Bacillus subtilis and exopeptidase derived from Aspergillus oryzae at a level of 0.1% (w/w). SHPH were rich in protein (90–91%) and amino acids (71–84%) but little fat (0.01–0.02%). The average molecular weight of SHPH was 300–1400. The effect of 5% SHPH (dry basis) addition on the state of water and denaturation of lizard fish myofibrils (Mf) during the dehydration process was evaluated by the desorption isotherm and the Ca-ATPase activity, and compared with the effect of sodium glutamate (Na-Glu). SHPH decreased the water activity and the Ca-ATPase inactivation, and increased monolayer sorbed water and multilayer sorbed water of Mf, although these effects of SHPH were smaller than those of Na-Glu. These findings suggest that the SHPH suppressed dehydration-induced denaturation of myofibrillar protein by stabilizing the hydrated water surrounding myofibrils. 相似文献
42.
43.
Orientation and integration of the classical and molecular genetic maps of chromosome 11 in rice 总被引:8,自引:0,他引:8
M. L. P. Abenes R. E. Tabien S. R. McCouch R. Ikeda P. Ronald G. S. Khush N. Huang 《Euphytica》1994,76(1-2):81-87
Summary The classical genetic map and molecular map of rice chromosome 11 were oriented to facilitate the use of these maps for genetic studies and rice improvement. Three morphological markers (d-27, z-2, and la) were crossed to a rice breeding line, IRBB21, which has the Xa-21 gene for bacterial blight resistance. Three F2 populations were analyzed with RFLP markers known to be located on chromosome 11. Segregation analysis of molecular markers and morphological markers was used to construct an RFLP map for each population. The recombination frequency between markers varied from population to population although the marker order on the maps was the same for all three populations. Based on a common set of markers mapped in the three populations, an integrated map was generated consisting of both RFLP and morphological markers. The genetic distance between markers on this map was determined by taking a weighted average of the data from the three populations. The oriented map serves as a bridge to understand the relationship between the classical and molecular linkage maps. Based on this information, the location of several genes on the classical map can be approximated with respect to RFLP markers without having to map them directly. 相似文献
44.
To evaluate windthrow resistance with respect to stem breakage, a nondestructive method for determining the shape of trunk
cross sections was developed. In this method, the coordinates of multiple gauge points set on the perimeter of a trunk are
calculated by measuring the distances between them. The shape between the gauge points is generated with the use of a profile
gauge placed between them. Measurement tests were conducted using profile gauges with lengths of 300 and 900 mm on model specimens
with four shape patterns and four different diameters. The accuracy of the estimation was verified by comparing the section
modulus calculated for the generated image and for the photograph. The average ratio of section modulus (generated/photo)
for all specimens was 0.994, which indicates that the proposed method is highly accurate. The section moduli of hollow trunks
can be evaluated using the profile method together with the drill resistance technique on the condition that 26% of the trunk
diameter could be drilled without skew. 相似文献
45.
Kana Yamashita Yasuhiko Hirakawa Shuetsu Saito Hiroshi Nakatani Motoyoshi Ikeda 《Journal of Wood Science》2011,57(5):363-370
To evaluate the bow variation in boxed-heart square timber of sugi (Cryptomeria japonica), bows from kiln-dried timber for five sugi cultivars with different longitudinal shrinkage trends were compared for two
stem heights. Two general trends were observed, depending on the cultivar: (1) either the bow was larger at the lower than
at the upper part of the stem, or (2) the bows at the lower and the upper parts of the stem were similar. In timber that had
larger bow values, the gradients of longitudinal shrinkage were large across the radius and along the length of the timber.
There was a positive relationship between the bow and longitudinal shrinkage. These results suggest that the bow variation
between the timbers was caused by a variation in longitudinal shrinkage, which was affected by the microfibril angle. Furthermore,
the bow was inversely proportional to the modulus of elasticity, which suggests that timber with a low modulus of elasticity
is susceptible to a large bow due to large longitudinal shrinkage. 相似文献
46.
In vivo antioxidative activity of propolis evaluated by the interaction with vitamins C and E and the level of lipid hydroperoxides in rats 总被引:4,自引:0,他引:4
Sun F Hayami S Haruna S Ogiri Y Tanaka K Yamada Y Ikeda K Yamada H Sugimoto H Kawai N Kojo S 《Journal of agricultural and food chemistry》2000,48(5):1462-1465
In vivo antioxidative activity of propolis was evaluated on the basis of ameliorative effects on the oxidative stress induced by vitamin E deficiency in rats. The control group was fed vitamin E-deficient diet, and the propolis group was fed vitamin E-deficient diet supplemented with 1% of propolis for 4 and 8 weeks. Comparisons were made in tissue concentrations of vitamin C, vitamin E, and lipid hydroperoxides between these groups. No significant difference was observed in tissue vitamin E concentration between these groups after both 4 and 8 weeks. After 4 weeks, the plasma vitamin C concentration of the propolis group was significantly higher than that of the control group. After 8 weeks, the tissue concentrations of vitamin C in the kidney, stomach, small intestine, and large intestine of the propolis group were significantly higher than those of the control group. These results suggest that some components of propolis are absorbed to circulate in the blood and behave as a hydrophilic antioxidant that saves vitamin C. The concentration of lipid hydroperoxides in the large intestine of the propolis group was significantly lower than that of the control group after 8 weeks. These results suggest that propolis exerts its antioxidative effect where it is assumed to accumulate, such as on the kidney, where it is excreted, and on the gastrointestinal tract, where propolis influences these tissues even from the outside of the cell. 相似文献
47.
Mutants defective in motility or antibiotics production were obtained by Tn5 mutagenesis of a biocontrol agent Pseudomonas fluorescens MelRC2Rif (wt). Tomato or melon seeds were co-inoculated with a Tn5 mutant and wt in a 1:1 ratio and then grown in soil for
10 days. There was no change in ratios of Tn5 mutants defective in antibiosis to wt in the process of rhizoplane colonization,
suggesting little contribution of in vitro antibiosis to the rhizoplane competence of P. fluorescens MelRC2Rif. Similar results were also obtained when seeds treated with bacteria were planted in soil artificially infested
with fungal pathogens. In contrast, ratios of Tn5 mutants defective in motility to wt significantly decreased, suggesting
the contribution of motility to the rhizoplane competence of this bacterium. When a non-motile Tn5 mutant and wt were co-inoculated
into soil at a matric potential of pF 2.3 (–20 kPa) and plants were then grown, there was no change in the ratio in rhizoplane
colonization, suggesting that motility might have a role in the movement along roots but an insignificant role in the movement
from bulk soil towards roots. When they were co-inoculated into 0.2% water agar (WA) instead of soil, a remarkable decline
in ratios was detected. Thus it was soil structure that hindered the efficiency of motility. Time course enumeration of rhizoplane
colonization of tomatoes grown in WA revealed that motility was an important means of movement towards and/or along roots
rather than the multiplication on roots.
Received: 8 July 1996 相似文献
48.
Grigera SA Perry RS Schofield AJ Chiao M Julian SR Lonzarich GG Ikeda SI Maeno Y Millis AJ Mackenzie AP 《Science (New York, N.Y.)》2001,294(5541):329-332
The concept of quantum criticality is proving to be central to attempts to understand the physics of strongly correlated electrons. Here, we argue that observations on the itinerant metamagnet Sr3Ru2O7 represent good evidence for a new class of quantum critical point, arising when the critical end point terminating a line of first-order transitions is depressed toward zero temperature. This is of interest both in its own right and because of the convenience of having a quantum critical point for which the tuning parameter is the magnetic field. The relationship between the resultant critical fluctuations and novel behavior very near the critical field is discussed. 相似文献
49.
Kumagai H Miyakawa K Negishi H Inoue H Obara K Suetsugu D 《Science (New York, N.Y.)》2003,299(5615):2058-2061
Very-long-period (VLP) signals showing simple decaying harmonic oscillations with periods near 10 seconds and lasting for about 300 seconds were observed in association with an earthquake swarm that occurred beneath Hachijo Island, Japan. Results from the source-mechanism analysis and waveform simulation based on a fluid-filled crack model consistently point to the resonance of a dike filled with a basaltic magma as the source of the VLP signals. Thus, VLP signals can be used to probe the state of the fluid and dynamic processes within a volcanic system. 相似文献
50.
Suzuki K Matsuo T Hashizume D Fueno H Tanaka K Tamao K 《Science (New York, N.Y.)》2011,331(6022):1306-1309
The cyclobutadiene (CBD) molecule C(4)H(4) deviates from a high-symmetry square geometry to compensate for its antiaromatic electronic structure. Here, we report a CBD silicon analog, Si(4)(EMind)(4) (1), stabilized by the bulky 1,1,7,7-tetraethyl-3,3,5,5-tetramethyl-s-hydrindacen-4-yl (EMind) groups, obtained as air- and moisture-sensitive orange crystals by the reduction of (EMind)SiBr(3) with three equivalents of lithium naphthalenide. X-ray crystallography reveals a planar and rhombic structure of the Si(4) four-membered ring, with alternating pyramidal and planar configurations at the silicon atoms. The large (29)Si chemical shift differences (Δδ > 350 parts per million) in the solid-state nuclear magnetic resonance spectra suggest a contribution of an alternately charge-separated structure. The rhombic-shaped charge-separated singlet state of compound 1 thus stabilizes its cyclic 4π-electron antiaromaticity in a manner that contrasts sharply with the bond-length alternation, characterizing the rectangular distortion of carbon-based CBD. 相似文献