全文获取类型
收费全文 | 189篇 |
免费 | 2篇 |
国内免费 | 1篇 |
专业分类
林业 | 22篇 |
农学 | 1篇 |
24篇 | |
综合类 | 12篇 |
农作物 | 8篇 |
水产渔业 | 33篇 |
畜牧兽医 | 68篇 |
园艺 | 1篇 |
植物保护 | 23篇 |
出版年
2022年 | 13篇 |
2021年 | 8篇 |
2020年 | 4篇 |
2019年 | 1篇 |
2018年 | 3篇 |
2017年 | 6篇 |
2016年 | 10篇 |
2015年 | 11篇 |
2014年 | 10篇 |
2013年 | 13篇 |
2012年 | 7篇 |
2011年 | 11篇 |
2010年 | 7篇 |
2009年 | 7篇 |
2008年 | 6篇 |
2007年 | 15篇 |
2006年 | 11篇 |
2005年 | 8篇 |
2004年 | 8篇 |
2003年 | 10篇 |
2002年 | 8篇 |
2001年 | 4篇 |
2000年 | 4篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1996年 | 1篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1963年 | 1篇 |
排序方式: 共有192条查询结果,搜索用时 15 毫秒
101.
Fourteen acridone alkaloids isolated from Lunasia amara Blanco were tested for their mechanism-based inhibition on human liver microsomal dextromethorphan O-demethylation activity, a prototype marker for cytochrome P450 2D6 (CYP2D6). Among the 14 compounds, 5-hydroxygraveroline (1), 8-methoxyifflaiamine (2), lunamarine (3), and lunine (12) increased their inhibitory activity with increasing preincubation time. Then, we further examined the possibility of mechanism-based inhibition on 5-hydroxygraveroline (1) and lunamarine (3), which showed the potent inhibition. Further investigations on 1 and 3 showed that the characteristic time- and concentration-dependent inhibition, which required a catalytic step with NADPH, was not protected by nucleophiles, and was decreased by the presence of a competitive inhibitor. Thus, 1 and 3 were concluded as mechanism-based inactivators of CYP2D6. 相似文献
102.
Kazuto Seki Ken Orihashi Mayumi Sato Masanori Kishino Naoto Saito 《Journal of Wood Science》2012,58(5):437-445
The quantitative compositions of the major constitutive diterpenoids in the rhytidome and secondary phloem of the branch bark of Kuril larch (Larix gmelinii var. japonica) were investigated. The eight major diterpenoids were isolated from a diethyl ether extract of the branch bark of L. gmelinii var. japonica and identified as 13-epimanool (1), larixol (2), larixyl acetate (3), 13-epitorulosyl acetate (4), abietic acid (5), neoabietic acid (6), dehydroabietic acid (7), and isopimaric acid (8). The amount of each diterpenoid was subsequently quantified in both the rhytidome and secondary phloem. All of the diterpenoids were present in both bark tissues, but the amounts were significantly higher in the rhytidome than in the secondary phloem. Developed fusiform resin cavities containing oleoresins were commonly observed in dead secondary phloem captured into the rhytidome of a bark transverse section. The accumulation and distribution of these constitutive diterpenoids in the bark tissues can probably be attributed to terpenoid biosynthesis in the living secondary phloem and the rhytidome formation process. From the viewpoint of constitutive chemical defense in conifers, it is suggested that the tree body may be more effectively defended against natural enemies by the higher amount of diterpenoid amount in the outermost and dead bark tissue, the rhytidome, where the potentially poisonous and easily oxidizable diterpenoids can be safely and stably maintained. 相似文献
103.
104.
Classification of lactic acid bacteria isolated from chigee and mare milk collected in Inner Mongolia 总被引:1,自引:0,他引:1
One hundred and seventeen isolates from chigee and 191 isolates from mare milk collected in Inner Mongolia were classified into six and 10 groups, respectively, based on the protein profiles obtained by sodium dodecyl sulfate‐polyacrylamide gel electrophoresis (SDS‐PAGE). A dendrogram on the basis of the molecular sizes of the protein bands was drawn and the similarity among the groups ranged from 96% to 44%. Representative isolates from all groups were identified by 16S rDNA sequencing and a phylogenetic tree was drawn. Furthermore, the results of carbohydrate fermentation tests of all groups were compared with those obtained by 16S rDNA sequencing and SDS‐PAGE analyzes. The isolates from chigee consisted of mainly Lactobacillus sp., Lactobacillus (Lb.) plantarum, Lb. pentosus and Lactococcus (Lc.) lactis ssp. cremoris were isolated at the rates of 48, 33 and 19%, respectively. The isolates from mare milk consisted of coccus, namely, Leuconostoc (Leuc.) mesenteroides, Leuc. pseudomesenteroides, Lc. garvieae, Lc. lactis ssp. lactis, Streptococcus (Sc.) parauberis and Enterococcus (Ec.) faecium. The isolation rates were 45, 19, 7, 8, 16 and 6%, respectively. The results demonstrated that the species isolated from chigee were different from those in mare milk. 相似文献
105.
We examined the effect of grazing during the growing phase on plasma glucose and insulin behavior at the end of the growing phase and at the early stage of the subsequent fattening phase in beef steers. From 13 to 45 weeks of age (growing phase), crossbred beef steers were grazed with minimal supplement (group G: n = 5) or housed while being fed on hay and concentrate (group H: n = 5). Following this phase, both groups were housed for finishing (fattening phase). At the end of the growing phase, group G showed faster plasma glucose disappearance after intravenous glucose infusion, with a smaller plasma insulin response, compared with group H. At the third week of the fattening phase, group G still showed higher glucose tolerance, although they experienced abrupt changes in nutritional and environmental factors. The results suggest that grazing during the growing phase probably improves the glucose tolerance and insulin response to glucose infusion in steers compared with animals that were housed during the corresponding period, and the improved properties may persist at least a few weeks after the commencement of fattening. 相似文献
106.
Hidenori MATSUI Yasunori ISSHIKI Masahiro EGUCHI Yohsuke OGAWA Yoshihiro SHIMOJI 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(2):181-186
We evaluated the protective efficacy of 94-kb virulence plasmid-cured, and phoP- or aroA-deficient strains of Salmonella enterica serovar Typhimurium (ΔphoP or ΔaroA S. Typhimurium) as oral vaccine candidates in BALB/c mice. Two weeks after the completion of 3 oral immunizations with 1 × 108 colony-forming units (CFU) of virulence plasmid-cured, and ΔphoP or ΔaroA S. Typhimurium at 10-day intervals, S. Typhimurium lipopolysaccharide (LPS)-specific mucosal secretory immunoglobulin A (s-IgA) antibody titers were detected in the cecal homogenate, bile and lung lavage fluid, but not in the intestinal lavage fluid. In addition, the increases in S. Typhimurium LPS-specific immunoglobulin G (IgG) and IgA antibody titers in the serum were also observed 2 weeks after completing 3 oral immunizations with virulence
plasmid-cured, and ΔphoP or ΔaroA S. Typhimurium. The series of 3 oral immunizations protected the mice against an oral challenge with 5 × 108 CFU of the virulent strain of S. Typhimurium, suggesting that both the virulence plasmid-cured, and ΔphoP and ΔaroA S. Typhimurium strains are promising candidates for safe and effective live S. Typhimurium vaccines. 相似文献
107.
Eriko Yahata Koreyuki Sugai Karma Penjore Yupa Hanboonsong Yasuhiro Takada Masamichi Nishiguchi Naoto Yamaoka 《Physiological and Molecular Plant Pathology》2009,74(2):161-166
When fungal germlings, after forming haustoria of Blumeria graminis f. sp. hordei (B. graminis), were removed from the surfaces of barley coleoptiles by cellulose acetate, followed by challenge inoculation with the non-pathogen Erysiphe pisi, they infected the nonhost barley coleoptile cells. This phenomenon was not observed on the coleoptile surface when the fungal germlings of B. graminis were removed before the formation of haustoria. Also, when the surface was inoculated with the pathogen of barley B. graminis as a challenger, after removing the fungal germlings of inducer post haustorial formation, the penetration efficiency of the fungi increased significantly compared with that of the control. Furthermore, when we extracted the crude-susceptibility inducing factor (suppressor) from coleoptiles before and after the formation of haustoria of B. graminis, suppressor activity against infection with E. pisi was observed only in the extract of barley coleoptiles that included haustoria of B. graminis about 18 h or later after inoculation. Surprisingly, however, the extract did not increase the penetration efficiency of B. graminis significantly. Thus, we hypothesize that the suppressor extracted from barley coleoptiles in which B. graminis had formed haustoria has no effect on increasing the penetration efficiency of the primary infection from the appressorium of B. graminis but has an effect on the infection with non-pathogen E. pisi. 相似文献
108.
Sumio Itoh Tetsuya Eguchi Naoto Kato Shigeru Takahashi 《Soil Science and Plant Nutrition》2013,59(4):540-550
Environmental samples of soil, plant and air dust collected after the Fukushima Daiichi Nuclear Power Plant accident were analyzed by autoradiograph, and significant amounts of radioactive particles containing higher cesium-134 (134Cs) and cesium-137 (137Cs) were found. Most of the radioactive soil particles were clay sized. The main part of the radioactivity and radioactive particles of air dust was detected from the 1.1–2.0μm fraction of an Andersen sampler filter. A considerable part of the radioactive particles on the air dust filter were not water soluble. Radioactive particles attached to outdoor plant leaves persisted for nearly 1 year. Thus, soil, leaf and air dust similarly contained sparingly water-soluble, micron-sized radioactive particles each with comparable ranges of elevated radio-Cs. A sheet dilution method was proposed and used to select and purify these radioactive particles. Using selected radioactive particles, the relation between area × gray value on autoradiograph and radioactivity was estimated. Radioactivity per particle was up to a few Bq and the geometrical average radioactivity of detected particles was around 0.1 Bq per particle or less. The configuration, chemical composition, origin and formation mechanisms of the radioactive particles require clarification. 相似文献
109.
Go Ogawa Masami Ishida Hidehiro Kato Yoshihiro Fujise Naoto Urano 《Fisheries Science》2010,76(2):177-181
There are few reports in the literature about the isolation of bacteria from whale intestine. In this report, we counted colony-forming
units in the feces obtained from three female common minke whales (Balaenoptera acutorostrata). The number of colony-forming units ranged from (2.2 ± 0.4) × 105 to (8.9 ± 2.0) × 108 per gram (wet weight) of excrement. 16S rRNA gene sequences of 141 isolates were determined. These strains were identified
as Enterococcus faecalis, Enterococcus sp., Enterobacter cloacae, Enterobacter sp., Escherichia coli, Edwardsiella ictaluri or Clostridium sp. The data suggested that the facultative anaerobic population of the intestinal bacterial flora of the minke whale was
similar to that of ground mammals. 相似文献
110.
Heavy metacercarial infections of cyprinid fishes in Uji River 总被引:2,自引:1,他引:2