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161.
Donatella Volpatti Bulfon Chiara Tulli Francesca Galeotti Marco 《Aquaculture Research》2013,45(1):31-44
The research was aimed to assess the effect of dietary carvacrol (0.025% and 0.05%) on sea bass (Dicentrarchus labrax) growth, immune response and resistance to Listonella anguillarum. Fish (69.2 ± 0.22 g) were fed the experimental diets for 9 weeks. Dietary carvacrol did not negatively affect fish survival, growth performance, feed intake and feed conversion ratio (P > 0.05) nor carcass yield and viscerosomatic, hepatosomatic and mesenteric fat index (P > 0.05). Serum and head kidney leucocytes were collected after 1, 4 and 8 weeks of feeding. Carvacrol significantly reduced serum proteins, immunoglobulins and lysozyme activity (P < 0.01) and moderately increased phagocytosis and pinocytosis of head kidney macrophages. The release of reactive oxygen species by leucocytes was reduced in carvacrol‐fed fish, even if significantly (P < 0.05) only in those fed 0.05% carvacrol for 1 week. Dietary carvacrol did not significantly affect the aspecific immune response, although a potential antioxidant activity might be speculated. Moreover, feeding carvacrol provided an appreciable resistance to a challenge with L. anguillarum, when a bacterial dose lower than the Lethal Dose50 was used. Cumulative mortality in fish fed 0.025% carvacrol was significantly lower than that of untreated controls (75% Relative Per cent Survival). 相似文献
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Danesi F Malaguti M Nunzio MD Maranesi M Biagi PL Bordoni A 《Journal of agricultural and food chemistry》2006,54(4):1203-1208
Many reports indicate that dietary selenium, potentially increasing the activity of glutathione peroxidase, could offer protection against free-radical-induced damage. The effects of diets moderately enriched in selenium, as sodium selenite or as a lyophilized selenium-rich food, were studied in rats. Adriamycin, an anticancer drug causing a free-radical-mediated cardiotoxicity, was administered intraperitoneally to some rats. The onset of an oxidative damage was indicated by the increase in the plasma level of reactive oxygen metabolites coupled to a decrease in the total antioxidant activity but without modification of glutathione peroxidase activity, which were observed in all rats, independent of the dietary treatment. On the contrary, in the heart, selenium supplementation caused an increase in the total antioxidant activity, glutathione concentration, and glutathione peroxidase and catalase activities leading to a decreased generation of reactive oxygen metabolites. These results clearly indicate that a moderate Se dietary supplementation counteracts adriamycin-induced cardiotoxicity by preservation of endogenous antioxidants. 相似文献
165.
Adam Ludford Victoria J. Cole Francesca Porri Christopher D. McQuaid Motebang D. V. Nakin Johan Erlandsson 《Landscape Ecology》2012,27(6):859-868
Source-sink theory has contributed to our understanding of the function of protected areas, particularly due to their role as population sources. Marine reserves are a preferred management tool for the conservation of natural populations, creating areas of good quality habitat and thus improving population connectivity by enhancing larval supply and recruitment among shores. Despite recent advances in the study of protected areas in the context of the source-sink theory, rigorous and empirical testing of marine reserves as metapopulation sources for the adjacent areas remain largely unexplored. We investigated the role of marine reserves as population sources, whether there was spill-over beyond the reserve boundaries and if so, whether spill-over was directional. We measured percentage cover and recruitment of mussels (Perna perna) at two reserves and two comparably sized exploited control areas on the south-east coast of South Africa where unprotected populations are severely affected by artisanal exploitation. Adult abundances were enhanced within reserves, but decreased towards their edges. We predicted that recruitment would mirror adult abundances and show directionality, with northern shores having greater recruitment following the prevalent northward flow of near-shore currents. There were, however, no correlations between adult abundances and recruitment for any months or shores, and no clear spatial patterns in recruitment (i.e. similar patterns occurred at reserves and controls). The results emphasise that, while reserves may act as important refuges by protecting adult abundances, their influence on promoting recovery of near-by exploited shores through larval spill-over may be overestimated. 相似文献
166.
Baldi A Pecorini C Rebucci R Saccone F Cheli F Miranda-Ribera A Lecchi C Ceciliani F 《Research in veterinary science》2012,93(2):758-762
It is well known that the plasminogen-activating (PA) system plays a key role in the bovine mammary gland during tissue remodelling. However, the modulation of the PA cascade after bacterial infections needs to be elucidated. This study examined the effects of Escherichia coli lipopolysaccharide (LPS) on cell viability, the modulation of cell-associated u-PA activity, and the regulation of u-PA and u-PA receptor (u-PAR) RNA expression using the BME-UV1 bovine mammary epithelial cell line. LPS did not affect cell viability, but induced an increase in u-PA activity, with the maximum response after 6 h of incubation. Moreover, u-PA and u-PAR mRNA expression were both up-regulated in BME-UV1 cells after 3 h of incubation with LPS. These data indicated that E. coli LPS led to an increase in u-PA activity and RNA expression of u-PA and u-PAR in BME-UV1 cells, thus strengthening the role of the PA system during pathological processes. 相似文献
167.
Bonelli Francesca Fratini F. Turchi B. Cantile C. Ebani V. V. Colombani G. Galiero A. Sgorbini M. 《Tropical animal health and production》2017,49(7):1489-1493
Tropical Animal Health and Production - Johne’s disease (JD) is an economically important infectious disease of ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP). This... 相似文献
168.
Evaluating a filtering and recirculating system to reduce dust drift in simulated sowing of dressed seed and abraded dust particle characteristics 下载免费PDF全文
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Characterization of a Potential Nutraceutical Ingredient: Pomegranate (Punica granatum L.) Seed Oil Unsaponifiable Fraction 总被引:1,自引:1,他引:0
Augusta Caligiani Francesca Bonzanini Gerardo Palla Martina Cirlini Renato Bruni 《Plant foods for human nutrition (Dordrecht, Netherlands)》2010,65(3):277-283
The chemical fingerprinting of the unsaponifiable fraction of different Punica granatum seed oils was performed in order to evaluate their potential as a functional food ingredient. Qualitative and quantitative
determinations of tocopherol, aliphatic alcohol (including policosanol), squalene, phytosterols and triterpene contents were
performed by GC-MS. A high yield (3.1–4.2%) of unsaponifiable matter was obtained and consistent levels of squalene (up to
800 mg/kg) and policosanol (118–185 mg/kg) were noticed. β-sitosterol (up to 8069 mg/kg) and cycloartenol (5916–7766 mg/kg)
were predominant in phytosterol and triterpene fractions, while β- and δ-tocopherol were the most abundant vitamin E forms.
Some minor variations were noticed between samples. From the results obtained, it can be suggested that the seed oil of P. granatum can be considered an interesting alimentary source of substances of nutraceutical value involved in the modulation of cholesterol
metabolism. 相似文献