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71.
Masachika Hirano Nobushige Itaya Isao Ohno Yoshio Fujita Hirosuke Yoshioka 《Pest management science》1979,10(4):291-294
Thirteen pyrethroid-type esters of substituted 1(or 3)-hydroxymethylimidazolidine-2, 4-dione were synthesised and their knockdown activities against houseflies, mosquitoes and cockroaches were examined. Knockdown activities of 2,4-dioxo-1-prop-2-ynylimidazolidin-3-ylmethyl esters in oil solutions were higher than those of known knockdown pyrethroids; three of the compounds also possessed strong knockdown and flushing-out activities against cockroaches. 相似文献
72.
73.
Majekodunmi O Fatope Suad Khamis S Al Burtomani Yoshio Takeda 《Journal of agricultural and food chemistry》2002,50(2):357-360
The seeds of Punica granatum, known as hap roman in the Arabian Peninsula, are commonly eaten as a dessert. As part of an ongoing project to find nonnutritional natural products which have health benefits, or that can be exploited to protect crops, the chloroform-soluble extract of the fermented seeds of P. granatum was found to be rich in 1-O-trans,cis,trans-9,11,13-octadecatrienoyl glycerol (1). The seed oil is not lethal to brine shrimp larvae. 1-O-isopentyl-3-O-octadec-2-enoyl glycerol (2) and the known cis-9-octadecenoic, octadecanoic, and eicosanoic acids were also detected in small amounts in the seed oil by LC and MS. The structure of 1 was determined from NMR and MS spectral data. 相似文献
74.
Masuda T Inaba Y Maekawa T Takeda Y Tamura H Yamaguchi H 《Journal of agricultural and food chemistry》2002,50(21):5863-5869
A solution of carnosic acid quinone, which is a radical chain-termination product having no antioxidant activity in the antioxidant reaction of carnosic acid, recovers potent antioxidant activity upon standing. The HPLC analysis of an aged solution of carnosic acid quinone revealed that several antioxidants are produced in the solution. From the time-course and quantitative analyses of the formation of the products and their structural analysis, an antioxidant mechanism from carnosic acid quinone is proposed that includes a redox reaction of carnosic acid quinone in addition to the isomerization to lactone derivatives. In the first stage of antioxidation, carnosic acid, the reduction product from carnosic acid quinone, contributes to the potent antioxidant activity of the solution. This proposed mechanism can explain one of the reasons for the strong antioxidant activity of the extract of the popular herbs sage and rosemary. 相似文献
75.
Red-Yellow soils are widely developed on terraces and hilly lands in the south-western half of Japan. They do not show any evidence of bleaching in the lower part of the A horizon, and are characterized by an extremely strong acid reaction, and a very low base-status9). There are few studies on clay mineralogy of Red-Yellow soils in Japan. Egawa et al4). have reported on clay mineralogy of soils derived from the Pleistocene and the Tertiary sediments most of which may be regarded as Red-Yellow soils. Matsui and Katô10) have described clay minerals of Red-Yellow soils derived from the Pleistocene sediment in the environs of Shinjobara, Shizuoka Prefecture. These investigations indicated that clay minerals of Red-Yellow soils derived from the Pleistocene sediments consisted mainly of kaolin minerals, whereas those of Red-Yell ow soils derived from the Tertiary sediments were of the kaolin-illite association. 相似文献
76.
Introduction One of the authors reported in the preceding paper the absorption by plants of unseparated fission products derived from the H-bomb detonated in Spring of 1954 at Bikini-atoll. Since the authors had, thereafter, some amounts of gross fission products which were waste of atomic pile by courtesy of United States Atomic Energy Commission, they began some experiments on the absorption of the gross fission products by plants. 相似文献
77.
The metabolism of exogenous glucose-14C in the light and the dark was studied in the detached leaves of tomato plants grown with ammonium nitrogen and nitrate nitrogen. In the light, 14CO2, release and incorporation of glucose into insoluble materials were hardly affected at all by the nitrogen sources. Among the soluble labelled amino acids, serine had the greatest amount of label in the ammonium-plants while aspartate had the greatest amount in the nitrate-plants. This aspartate was synthesized from C3-compounds by carboxylation. During dark-light transition, the change in the composition of soluble amino acids was more rapid in the ammonium-plants than in the nitrate-plants. In the dark, 14CO2-release, which was ten times as much as in the light, was larger in the ammonium-plants than in the nitrate-plants; but the synthesis of high molecular compounds from glucose in the ammonium-plants was about half that in the nitrate-plants. So, it is considered that respiration operates sufficiently in the ammonium-plants. The effects of DCMU and a 100% O2 atmosphere on glucose metabolism in both groups of plants were studied and the respiration of leaves in the light was discussed. 相似文献
78.
79.
Akhil Ranjan Baruah Noriko Ishigo-Oka Mieko Adachi Yasuyo Oguma Yoshiro Tokizono Kazumitsu Onishi Yoshio Sano 《Euphytica》2009,165(3):459-470
The present study was conducted to understand the pattern of variation and the genetic bases for cold tolerance at the early
growth stage in Asian rice. The genetic variation was investigated at the germination, plumule and seedling stages among 57
strains including cultivated rice (Oryza sativa ssp. indica and ssp. japonica) and its wild progenitor (Oryza rufipogon). The significant differentiation of cold tolerance was observed among the taxonomically divided groups. At the germination
stage, both indica and japonica subspecies tended to be more tolerant than O. rufipogon, whereas at the plumule and seedling stages, ssp. japonica tended to be more tolerant than ssp. indica and O. rufipogon. Furthermore, in cold tolerance at the plumule stage, the clinal variation across the latitude of origins was observed within
O. rufipogon and ssp. japonica, suggesting that the current pattern of variation seems to have been shaped by both their phylogenetic histories and on-going
adaptation to the local environments. QTL analysis between O. sativa ssp. japonica (tolerant) and O. rufipogon (susceptible) revealed five putative QTLs for cold tolerance at the plumule and seedling stages but not at the germination
stage. Substitution mapping was also carried out to precisely locate the two major QTLs for cold tolerance at the plumule
stage, which could be used for improvement of tolerance to cold stress in ssp. indica. 相似文献
80.
Tomohiro Nishizono Kunihiro Tanaka Kazuo Hosoda Yoshio Awaya Yasuhiko Oishi 《Journal of Forest Research》2008,13(5):264-274
We analyzed data from 28 long-term experimental monitoring plots installed in Japanese cedar (Cryptomeria japonica D. Don) plantations in northeastern Japan to examine how site productivity and thinning practices relate to culmination in
stand growth. Site productivity and thinning practices in the plots were evaluated by site index (dominant tree height at
40-years old) and by cumulative thinning rate (cumulative thinning volume divided by cumulative gross production during the
entire period of measurement). Culmination of stand growth was evaluated by culmination age of the mean annual increment (MAI)
and its maximum value (Max MAI). Max MAI for the mean annual gross increment (MAIgross) and mean annual net increment (MAInet)
increased with increasing site index, but did not change with cumulative thinning rate. Culmination age for MAIgross decreased
with increasing site index, but did not change with cumulative thinning rate. Culmination age for MAInet decreased with increasing
site index. Additionally, culmination age for MAInet increased with increasing cumulative thinning rate in sites with a high
site index (>19.3 m) but not in those with a low site index (<19.3 m). These results indicate that thinning extends the culmination
age without changing Max MAInet under high site productivity. Therefore, thinning increases total net yield in sites with
high productivity based on a long-term perspective. 相似文献