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151.
A rigid-type of polyethylene T-cannula was fitted into the anterior ileum of six horses in order to improve the cannulation techniques. A piece of polyethylene net was fastened onto the intestinal wall around the cannula to prevent dislodgment of the cannula by promoting a secure adhesion between the ileum and the abdominal wall. The cannula barrel sheathed with silicone tubing was exteriorized through a stab incision at the lateral ventral wall on the transverse line of the second lumber vertebra, and a flange was screwed onto the barrel. The feeding regime gradually increased concentrate without roughage prevented any colic signs. The use of these techniques succeeded in the ileal cannulation with no leakage of digesta.  相似文献   
152.
ABSTRACT:   Incidental catches in pelagic longline fishing pose a serious threat to sea turtle populations throughout the world's seas and oceans. In this work, carried out in the framework of the EC-DG-Fisheries 98/008 project, information on sea turtle catch rates from swordfish and albacore longline fishing activities observed in Italian waters off the Ionian Sea during 1999 and 2000, are reported. In addition, biometric data, health status, and tagging return rate of sea turtles captured are provided. A total of 200 sea turtles were caught (198 loggerhead turtles and 2 green turtles), comprising 0.5–15.7% of the total catch in number of individuals. The estimates of the sea turtles caught by the total fishing effort of both longlines in the whole study area were 1084 specimens in 1999 (95% CI = 667–1502) and 4447 specimens in 2000 (95% CI = 3189–5705). Although all sea turtles were released alive, nearly half of them had hooks that could not be removed and remained deeply embedded in the digestive tract.  相似文献   
153.
We have previously reported growth-promoting effects of recombinant bovine growth hormone (rbGH) in Mozambique tilapia, Oreochromis mossambicus, after 4 weekly injections or a single injection of slow-releasing formulation (Posilac®) (Leedom et al. 2002). In order to obtain further understanding of the role of the growth hormone (GH)-insulin-like growth factor-I (IGF-I) axis in growth in the tilapia, the effects of rbGH on plasma and mRNA levels of IGF-I were examined. Plasma IGF-I levels were significantly increased after rbGH and Posilac® injections, and a significant correlation was observed between plasma IGF-I levels, body length and mass in both treatments. IGF-I mRNA levels in the liver and in the skeletal muscle were also significantly increased after rbGH and Posilac® injections, indicating that IGF-I gene expression in these tissues is under control of circulating GH. IGF-I mRNA levels in the gill were not affected by treatment. Liver IGF-I mRNA levels were significantly correlated with body length and with body mass after rbGH and Posilac® injections. These results indicate that the growth-promoting effect of rbGH in this species is mediated to a significant extent via its stimulation of hepatic production of IGF-I and the resulting increase in plasma IGF-I, and also possibly through locally produced IGF-I in the skeletal muscle, acting in a paracrine or autocrine fashion.  相似文献   
154.
The involvement of testosterone (T), estradiol-17β (E2), 11-ketotestosterone (11-KT), 17,20β-dihydroxy-4-pregnene-3-one (DHP), luteinizing hormone (LH), thyroxine (T4), and triiodothyronine (T3) in the regulation of downstream and upstream movement (swimming behavior) was investigated in land-locked sockeye salmon Oncorhynchus nerka, using an artificial raceway. During the downstream migratory period, T implant resulted in high plasma T levels and inhibited the occurrence of downstream swimming behavior (negative rheotaxis) in yearling (1+) immature smolts. In terms of upstream behavior, 2-year-old (2+) males exhibited high plasma T and 11-KT levels, while 2+ females had elevated T and DHP levels. In 1+ immature fish, a T implant induced upstream swimming behavior (positive rheotaxis). In experiments 1 and 3, the plasma T4 and T3 levels of non-migrants tended to be higher than those of migrants. In contrast, no marked changes in plasma and pituitary LH were found in both downstream and upstream migrants. These results suggest that sex steroids, such as T, play significant roles in the regulation of downstream and upstream swimming behaviors in land-locked sockeye salmon.  相似文献   
155.
156.
There is an increasing interest in indigenous fruit trees (IFTs) and their potential role for agroforestry, food security and poverty alleviation. Despite the growing numbers of studies on IFTs in Africa, little research has focused on the rainforest zone outside Cameroun and Nigeria. This study investigated if the important IFTs of Sierra Leone are among those previously identified as ‘priority’ species for this zone and, as they are not, a new approach combining focus-group data, field observations, a market survey and a ranking exercise was used to determine which IFTs have highest potential for agroforestry in a given area. Results indicated that the most important IFTs in Sierra Leone as established by local farmers are Parinari excelsa Sabine, Cola lateritia K. Schum., Pentaclethra macrophylla Benth., Heritiera utilis (Sprague) Sprague and Bussea occidentalis Hutch. However, following the ranking exercise, the species H. utilis, Garcinia kola Heckel and Beilschmiedia mannii (Meisn.) Benth. et Hook. f. ex B. D. Jacks., highly appreciated by locals, already managed by some farmers and reported ‘difficult to find in the wild’, were found to have the highest potential for agroforestry in the country. The findings highlighted that previous IFTs prioritization in Cameroun and Nigeria were not representative of the whole African rainforest zone. A new approach was successfully used to identify the IFTs with greatest potential for agroforestry in Sierra Leone. This simple cost-effective approach, which straightforwardly identifies opportunities and challenges for each species, could be used elsewhere in the tropics to establish a baseline for future domestication programs.  相似文献   
157.
Agricultural headwater ditches are an important source of indirect agricultural nitrous oxide (N2O) emissions, but their contribution is difficult to quantify. In the present study, the static chamber-gas chromatography technique was used for measurement of N2O emissions from vegetated (V, the whole ditch ecosystem) and non-vegetated (NV, the sediment-water interface only) zones in an agricultural headwater ditch in the Central Sichuan Basin in Southwestern China during 2014–2015. Annual N2O emissions from the agricultural headwater ditch were similar to direct N2O emissions from an adjacent N-fertilized purple soil cropland, suggesting nitrogen (N)-enriched ditches are important anthropogenic N2O sources. Mean cumulative N2O emissions during summer and autumn were higher than those in spring and winter. Overlying water nitrate (NO3 ?-N) concentration and sediment-water interface temperature were primary factors affecting seasonal N2O emissions. Heavy precipitation transported NO3 ?-N from cropland and increase NO3 ?-N in the agricultural headwater ditch water, and subsequently stimulate N2O emissions. A literature review of EF5r (the indirect N2O emission factor for rivers) revealed a mean value of 0.23%, similar to our values (0.27%), and also the default value (0.25%) proposed by the Intergovernmental Panel on Climate Change. The number of studies on indirect N2O emissions remains limited, and more in situ measurements are needed to have more accurate values of EF5r.  相似文献   
158.
To evaluate the effect of adjacent tree species on the susceptibility of Japanese black pine (Pinus thunbergii) to pine wilt disease, an inoculation experiment was conducted usingP. thunbergii seedlings potted with seedlings of six tree species,i. e. Alnus sieboldiana, Eurya japonica, Lespedeza bicolor formacutifolia, Pinus thumbergii, Robinia pseudo-acacia andSarothamus scoparius. About ten months after planting, they were inoculated with the pinewood nematode (Bursaphelenchus xylophilus) in early July 1992. After that, the proportion of pine seedlings with completely discolored foliage increased more quickly when the seedlings were potted withR. pseudo-acacia, S. scoparius orA. sieboldiana than when potted withP. thunbergii, L. bicolor orE. japonica. At the end of the study period, 17 weeks after inoculation, it reached 90.6%, 90.0%, 87.5%, 72.7%, 63.3%, and 59.4% when the pine seedlings were potted withR. pseudo-acacia, S. scoparius, A. sieboldiana, P. thunbergii, L. bicolor andE. japonica, respectively. This indicated that the susceptibility ofP. thunbergii seedlings to pine wilt disease was influence by the species of adjacent trees.  相似文献   
159.
The melting peach cultivar “Akatsuki” [Prunus persica L. Batsh] develops melting texture during ripening, but the stony-hard peach cultivar “Odoroki”, softens and develops a mealy texture when treated with propylene. Cell wall polysaccharides were fractionated as 1,2-diaminocyclohexanetetraacetic acid (CDTA)-, Na2CO3-, NaOH-soluble fractions, or the cellulosic residues that remained after solvent extraction. Size-exclusion chromatography of the CDTA-soluble fraction revealed a limited depolymerization of polyuronides in mealy “Odoroki” fruit, accompanying a lower level of endo-polygalacturonase (endo-PG) and a higher level of exo-PG activities compared to melting “Akatsuki” fruit. “Akatsuki” fruit showed increases in the arabinose, galactose and rhamnose contents in the CDTA-soluble fraction. These neutral sugars decreased in the Na2CO3-soluble and cellulosic residue fractions during ripening. Similar changes were observed for neutral sugars other than arabinose during softening in mealy “Odoroki” fruit. Arabinose content did not increase in the CDTA-soluble fraction of “Odoroki” fruit; however, arabinose content decreased in the Na2CO3-soluble fraction and in the cellulosic residue as observed for “Akatsuki” fruit. A significant increase in α-l-arabinofuranosidase activity, about 10 times higher than for “Akatsuki” fruit, was observed in propylene-treated mealy “Odoroki” fruit. Differences in ripening-associated metabolic changes in the cell walls of these peach cultivars seem to be related to their differences in texture.  相似文献   
160.
The effects of postharvest application of aminoethoxyvinylglycine (AVG) and 1-methylcyclopropene (1-MCP) on ethylene production and fruit quality, and thus on transportation and shelf-life, were evaluated in melting-flesh peaches. AVG (150 mg L−1) significantly reduced ethylene production, and the effect was enhanced in combination with 1-MCP (1 μL L−1). However, fruit treated with AVG alone softened to untreated control levels 2 d after harvest (DAH). Treatment with 1-MCP significantly reduced the rate of softening until 2 DAH, but the fruit rapidly softened thereafter, and reached untreated control levels by 4 DAH. A combination of AVG and 1-MCP significantly reduced fruit tissue softening throughout ripening. The effect of each chemical on flesh firmness indicated that 1-MCP affected fruit response in the early stages of ripening up to 4 DAH, and AVG significantly reduced softening in the latter stages from 4 to 9 DAH. Peaches treated with AVG and 1-MCP retained their ground color during ripening, but the effect of each chemical on color is unclear. The present study indicates that combined treatment with AVG and 1-MCP significantly delays the ripening of melting-flesh peaches.  相似文献   
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