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61.
A series of N'-benzoheterocyclecarbonyl-N-tert-butyl-3,5-dimethylbenzohydrazide analogues possessing a variety of substituents on the benzene rings of the benzoheterocyle moieties were synthesized and tested for their insecticidal activity. The introduction of a methyl group at the R1 position of the benzoheterocycle moiety strongly increased the insecticidal activity. Among the analogues synthesized, N'-tert-butyl-N'-(3,5-dimethylbenzoyl)-5-methyl-6-chromanecarbohydrazide showed the highest insecticidal activity (LC50 = 0.89 mg litre(-1)).  相似文献   
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63.
The present study was conducted to evaluate whether supplementation of semen extender with glutathione (GSH) can maintain the quality of frozen-thawed canine spermatozoa. Eighteen ejaculates were obtained from 5 dogs and placed in extender (20% egg yolk, Tris, citric acid, lactose, raffinose, antibiotics and 6.5% glycerol) containing 0 (control), 2.5, 5, 7.5 or 10 mM GSH. The samples were cooled to 4 C and then frozen in liquid nitrogen vapor. Motility parameters of the sperm were evaluated at 0, 1, 2, 3, 4, 12 and 24 h after thawing. Sperm motility was higher in the 5 mM GSH group than in the control or 2.5 and 10 mM GSH groups; this effect was observed at 1 to 24 h after thawing (P < 0.05). The 5 mM GSH group had a higher sperm viability index at 12 and 24 h after thawing compared with the other groups (P < 0.05). Acrosome integrity, evaluated at 4 h after thawing, was greater in two of the GSH-treated groups (5 and 10 mM) compared with the control. Lipid peroxidation (LP) levels immediately after thawing were lower in the 5 and 10 mM GSH groups compared with the control, while those at 12 h after thawing did not differ significantly. Frozen-thawed semen in the 5 mM GSH group was used for transcervical insemination of 4 bitches, resulting in delivery of 5 puppies from 2 bitches. These results indicate that supplementation of semen extender with 5 mM GSH was effective in improving motility, longevity and acrosomal integrity and inhibiting LP levels in post-thaw canine spermatozoa, without any adverse impacts on full-term development after transcervical insemination.  相似文献   
64.
The ability of grape cultivars to produce resveratrol in response to UV radiation is associated with their resistance to fungal pathogens. In this study, we evaluated the UV-induced resveratrol production potential of grape flowers and green berries of 72 grape genotypes. Their ability to produce resveratrol in response to UV radiation was used to establish a selection criterion for screening genotypes for resistance to gray mold and powdery mildew. We quantified resveratrol in grape flower extracts from pre-bloom and early bloom flowers after exposure to UV radiation. There was a strong negative correlation between UV-induced resveratrol production and susceptibility to Botrytis infection. The grape genotype was considered to be susceptible to gray mold when the resveratrol content of whole flower clusters was less than 10 μg g−1 FW after the UV treatment. We determined resveratrol production in response to UV radiation in whole grape berries from 0 to 30 days after full bloom. The ability to produce resveratrol in response to UV increased by 8- to 20-times during this period, depending on the genotype. At 30 days after full bloom, Vitis vinifera genotypes generally had low levels of resveratrol (<50 μg g−1 FW), while interspecific hybrids, especially the North American cultivars, had high levels (>50 μg g−1 FW). There were clear varietal differences in resistance to Erysiphe (powdery mildew) infection. Susceptibility to Erysiphe infection was strongly negatively correlated with UV-induced resveratrol production.  相似文献   
65.
66.
Although there have been some attempts to obtain intergeneric hybrids between Japanese pear (Pyrus pyrifolia Nakai) and apple (Malus × domestica Borkh.) mature hybrids have not been generated due to hybrid lethality. Shoots from immature hybrid embryos were gamma irradiated and cultured at normal temperature conditions to obtain viable intergeneric plants. Gamma irradiation doses of 50 and 100 Gy cultured at 25 °C killed all shoots but there was one survivor at 150 Gy and 25 °C. Hybrid status of the shoot was confirmed by using morphology, flow cytometry and SSR markers. The intergeneric plant had similar leaf serrations to apple and similar petioles to Japanese pear. Flow cytometric analysis revealed that the intergeneric shoot had a DNA content intermediate between the parents. SSR analysis showed one allele from each parent for all 16 SSR loci investigated. These data strongly suggest that the obtained shoot is a true hybrid between Japanese pear and apple.  相似文献   
67.
ABSTRACT:   From 2002 to 2006, the fish fauna associated with sea weeds drifting in the Chikuzen Sea, northern Kyushu, Japan, was examined. The total numbers of species and individuals collected were 51 and 5475, respectively. The five dominant species, accounting for approximately 80% of the total individuals, were Rudarius ercodes , Stephanolepis cirrhifer , Petroscirtes breviceps , Sebastes thompsoni and Paramonacanthus japonicus . The number of species and individuals increased significantly with the increase in water temperature, reaching maxima during early summer and autumn, respectively. Combining the present and previous data (∼50 years ago), the appearance patterns of the fishes associated with drifting sea weed were classified into the following four types: (i) long periods (continuously for 3 months or more) and autumn (LA); (ii) spring (SP); (iii) summer (SU); and (iv) rare (R). In more than half of the species, there were no changes in the appearance patterns between the present and previous studies. However, in the present study, the appearance patterns of several species changed from LA to R ( Oplegnathus punctatus and Kyphosus cinerascens ) and from R to LA and SU ( Abudefduf vaigiensis and Hyperoglyphe japonica , respectively).  相似文献   
68.
Melissococcus plutonius is an important pathogen that causes European foulbrood (EFB) in honeybee larvae. Recently, we discovered a group of M. plutonius strains that are phenotypically and genetically distinct from other strains. These strains belong to clonal complex (CC) 12, as determined by multilocus sequence typing analysis, and show atypical cultural and biochemical characteristics in vitro compared with strains of other CCs tested. Although EFB is considered to be a purely intestinal infection according to early studies, it is unknown whether the recently found CC12 strains cause EFB by the same pathomechanism. In this study, to obtain a better understanding of EFB, we infected European honeybee (Apis mellifera) larvae per os with a well-characterized CC12 strain, DAT561, and analyzed the larvae histopathologically. Ingested DAT561 was mainly localized in the midgut lumen surrounded by the peritrophic matrix (PM) in the larvae. In badly affected larvae, the PM and midgut epithelial cells degenerated, and some bacterial cells were detected outside of the midgut. However, they did not proliferate in the deep tissues actively. By immunohistochemical analysis, the PM was stained with anti-M. plutonius serum in most of the DAT561-infected larvae. In some larvae, luminal surfaces of the PM were more strongly stained than the inside. These results suggest that infection of CC12 strain in honeybee larvae is essentially confined to the intestine. Moreover, our results imply the presence of M. plutonius-derived substances diffusing into the larval tissues in the course of infection.  相似文献   
69.
Terrestrial invertebrates falling from the riparian canopy are a major energy source for fishes in headwater streams. Because quantity and quality of such allochthonous resources can vary depending on riparian conditions, conversion of riparian forests to conifer plantations may affect stream productivity. We compared falling and drifting invertebrate abundances and the diet of masu salmon (Oncorhynchus masou) among stream reaches bordered by deciduous broadleaved forests, conifer plantations (Cryptomeria japonica), and clear‐cut sites in southwestern Japan. We also examined whether among‐reach variation in salmon abundance was related to the riparian vegetation types. The results indicated that, on an annual basis, falling inputs of terrestrial invertebrates at the broadleaved reaches were 2–4 times higher than those at the plantation and clear‐cut reaches. In nonwinter seasons, terrestrial invertebrates made up 40–60% and 30–90% of drift and masu salmon diets, respectively, and drifting invertebrate abundance was higher in the broadleaved reaches than in the plantation reaches. Furthermore, a multivariate analysis of salmon abundance showed that variation in salmon biomass was explained primarily by riparian vegetation type, with broadleaved and clear‐cut reaches having higher biomass than the plantation reaches. These results indicate that terrestrial invertebrates are an important resource for masu salmon, and suggest that streams bordered by conifer plantations receive lower terrestrial prey inputs, which results in lower salmon abundance. In regions where natural forests have been extensively converted to conifer plantations, forest management that allows and facilitates recovery of natural riparian stands is important.  相似文献   
70.
The key enzymes of the glyoxylate cycle, isocitrate lyase (ICL) and malate synthase (MS), were detected in varying amounts in the mycelia of the woodrotting basidiomycetes tested, although they were grown in a glucose-rich medium. The highest specific activities of ICL (0.37 U/mg protein) and MS (0.63 U/mg protein) were measured for the brown-rot basidiomycetesLaetiporus sulphureus andFomitopsis palustris, respectively. The results indicate that the glyoxylate cycle enzymes occur in wood-rotting basidiomycetes as the seemingly constitutive enzymes at varying levels. The glyoxylate cycle enzymes, including malate dehydrogenase (MDH), and the oxalate-producing enzymes glyoxylate dehydrogenase (GDH) and oxaloacetase (OXA) were found to have good correlation with biosynthesis of oxalic acid and fungal growth, which was also confirmed by use of an ICL inhibitor. A new role for the glyoxylate cycle is discussed in relation to oxalic acid biosynthesis in wood-rotting basidiomycetes.This paper was presented in the 50th annual meeting of the Japan Wood Research Society, Kyoto, April 2000  相似文献   
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