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排序方式: 共有316条查询结果,搜索用时 375 毫秒
61.
Masumi Yamagishi Motoyasu Otani Mariko Higashi Yoshimichi Fukuta Kiichi Fukui Takiko Shimada 《Euphytica》1998,103(2):227-234
Diallel analysis has revealed that anther culturability in rice (Oryza sativa L.) is a quantitative trait controlled by the
nuclear genome. Mapping of anther culturability is important to increase the efficiency for green plant regeneration from
microspores. In the previous study, we detected distorted segregation of RFLP markers in rice populations derived from the
anther culture of an F1 hybrid between a japonica cultivar ‘Nipponbare’ and an indica cultivar ‘Milyang 23’. To clarify the association between chromosomal
regions showing distorted segregation and anther culturability, the anther culturability of doubled haploid lines derived
from the same cross combination was examined, and the association between alleles of the RFLP markers, which exhibiting the
most distorted segregation on chromosomes 1, 3, 7, 10 and 11, and the anther culturability was evaluated. One region on chromosome
1 was found to control callus formation from microspores, and one region on chromosome 10 appeared to control the ratio of
green to albino regenerated plants. In both regions, the Nipponbare allele had positive effects. Three regions on chromosomes
3, 7 and 11, however, showed no significant effect on anther culturability.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
62.
Yoshioka Miwa Matsuo Yu Nemoto Yurika Ogushi Mariko Onodera Munenaka Yoshie-Stark Yumiko 《Fisheries Science》2020,86(1):215-229
Fisheries Science - Traditional Japanese koji-fermented tofu (tofuyo) processing was simulated to make fermented seafood. The koji fermentation process at room temperature was applied to steamed... 相似文献
63.
64.
Hiroshi Oikawa Yukihiko Matsuyama Masataka Satomi Yutaka Yano 《Fisheries Science》2008,74(5):1180-1186
The accumulation of paralytic shellfish poisoning (PSP) toxin in the crab Charybdis japonica was investigated in Kure Bay, when a bivalve Mytilus galloprovincialis, in the same water, showed toxicity caused by PSP toxin. In 2005, 17 specimens of the crab had PSP toxin over 4 MU/g in the
hepatopancreas, and the highest toxicity was at 37.4 MU/g. Since the regulation limit of PSP for crab hepatopancreas was set
in 2004, this is the first observation of regulatory level of PSP toxin in C. japonica. Unlike in the hepatopancreas of the crab, the hazardous level of the toxin was not detected in the muscle of the cephalothorax
and the appendage. The toxin accumulation in the crab was also investigated by feeding toxic mussels to the crab. The crab
retained the toxin mainly in the hepatopancreas, and the ratio of retention in the crab was from 12.9 to 24.6%. The toxin
profiles, shown in the feeding experiments, suggest that the transformation of PSP toxin occurs in the crab because dcGTX2
and dcGTX3 was detected in all crab specimens despite the lack of these analogs in the mussels used as feed. 相似文献
65.
66.
Compressive deformation of wood impregnated with low molecular weight phenol formaldehyde (PF) resin III: effects of sodium chlorite treatment 总被引:1,自引:0,他引:1
To obtain high-strength phenol–formaldehyde (PF) resin-impregnated compressed wood at low pressing pressure, we investigated the effects of sodium chlorite (NaClO2) treatment on wood prior to low molecular weight PF resin impregnation. Sawn veneers of Japanese cedar (Cryptomeria japonica) were treated with 2% aqueous NaClO2 solution at 45°C for 12 h to remove lignin, and the process was repeated up to four times, resulting in weight loss of 21%. NaClO2 treatment has shown considerable potential for high compression of PF resin-impregnated wood at low pressing pressure, especially after adding moisture to a content of 10%–11%. This deformation is further enhanced during pressure holding by creep deformation. The density, Young’s modulus, and bending strength of PF resin-impregnated veneer laminated composites that were treated with NaClO2 four times and compressed at 1 MPa, reached 1.15 g/cm3, 27 GPa, and 280 MPa, respectively. The values in untreated PF resin-impregnated wood reached 0.8 g/cm3, 16 GPa, and 165 MPa, respectively. 相似文献
67.
Mariko Shoji Hidenori Sato Remi Nakagawa Ryo Funada Takafumi Kubo Shinjiro Ogita 《Journal of Forest Research》2006,11(6):449-453
The effect of an osmoticum, polyethylene glycol (PEG), on somatic embryo production was examined using embryogenic cells of
Pinus densiflora. In the basal medium containing 30 μM abscisic acid and 6% maltose, the quality of the embryos formed was poor even though
somatic embryos were produced. The addition of PEG with molecular weight of 4000 or 8000 significantly enhanced the development
of both the quality and quantity of somatic embryos. Furthermore, higher levels of a constant osmotic pressure with PEG 8000
in a range from about 300 to 450 mmol/kg could remarkably enhance the morphogenesis of somatic embryos and their number of
embryos produced. A higher stable osmotic pressure with an appropriate molecular weight of PEG is a key factor for the production
of good quality somatic embryos in P. densiflora. 相似文献
68.
Mariko Yoshioka Keiji Takabe Junji Sugiyama Yoshiyuki Nishio 《Journal of Wood Science》2006,52(2):121-127
New biodegradable cellulose acetate/layered silicate grafted poly(ε-caprolactone) [(CA/layered silicate)-g-PCL] nanocomposites were prepared by in situ polymerization of ε-caprolactone in the presence of cellulose acetate (CA) and organically modified layered silicate (OMLS). The structures of
the resulting composites were investigated. X-ray diffractometry was carried out to survey general structural features of
(CA/OMLS)-g-PCL nanocomposites, and revealed that OMLSs having hydroxyl groups in the organic modifiers greatly altered the layered silicate
structure by monomer intercalation and successive exfoliation through its polymerization. Two of the representative cases
were characterized by wide-angle and small-angle X-ray scattering analyses with a synchrotron source. The morphology of these
nanocomposites was further examined by transmission electron microscopy. When SPN, one of OMLSs having one hydroxyl group
in its modifier, was used, the silicate layers could not be dispersed thoroughly, but existed as aggregates consisting of
several silicate layers. Among them, the crystal growth of PCL developed by transcrystallization, where the crystal growth
was restricted in the confined space. When Cloisite 30B, having two hydroxyl groups within the modifier, was used, the silicate
layers forming the clay were dispersed completely in the composite and random orientation of the OMLS was observed. 相似文献
69.
Summary As a reagent source for the formalization of wood, trioxane was used instead of conventional paraformaldehyde. From preliminary experiments it became apparent that trioxane depolymerizes to formaldehyde by heating in the presence of some metallic salts. Formalization of wood with trioxane was carried out under the catalysis of sulfur dioxide (SO2) along with these salts. The hygroscopic and acoustic properties were considerably improved by the treatment. Especially when the reaction was catalyzed by a combination of SO2 and Fe2(SO4)3, the antiswelling efficiency (ASE) reached nearly 70%, the specific dynamic Young's modulus (E/) in the radial direction increased about 20%, and the loss tangent (tan ) decreased about 30% and 50% in the longitudinal and radial directions, respectively. In this case, the modulus of rupture did not appreciably decrease in the radial direction. This is comparable to the most prominent results obtained so far by SO2 catalyzed formalization with tetraoxane. It can be concluded that trioxane is very effective as a reagent source for formalization. The increase in acoustic converting efficiency,
, of about twofold in the radial direction and decrease in hygroscopicity of more than 60% should not only enrich the sound volume of musical instruments but also stabilize their tone quality against humidity changes. 相似文献
70.
For plywood specimens under shear through the thickness, a fatigue life prediction method based on strain energy has been
newly developed with the fatigue process and failure criterion applicable to various loading conditions. Once the fatigue
process and failure criterion of the plywood specimen were determined by the fatigue data measured under a loading condition
other than the square loading waveform, the fatigue life of a specimen under various loading conditions could be predicted
easily and accurately by the first cycle loading test. The relationship between stress level and the predicted fatigue life
was also similar to that between stress level and the experimentally determined fatigue life. The fatigue life prediction
method proposed may be widely applicable to the prediction of the fatigue life of solid wood and wood composites. 相似文献