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51.
Calorie restriction promotes mitochondrial biogenesis by inducing the expression of eNOS 总被引:2,自引:0,他引:2
Nisoli E Tonello C Cardile A Cozzi V Bracale R Tedesco L Falcone S Valerio A Cantoni O Clementi E Moncada S Carruba MO 《Science (New York, N.Y.)》2005,310(5746):314-317
Calorie restriction extends life span in organisms ranging from yeast to mammals. Here, we report that calorie restriction for either 3 or 12 months induced endothelial nitric oxide synthase (eNOS) expression and 3',5'-cyclic guanosine monophosphate formation in various tissues of male mice. This was accompanied by mitochondrial biogenesis, with increased oxygen consumption and adenosine triphosphate production, and an enhanced expression of sirtuin 1. These effects were strongly attenuated in eNOS null-mutant mice. Thus, nitric oxide plays a fundamental role in the processes induced by calorie restriction and may be involved in the extension of life span in mammals. 相似文献
52.
E. Playán J. Cavero I. Mantero R. Salvador S. Lecina J.M. Faci J. Andrés V. Salvador G. Cardeña S. Ramón J.L. Lacueva M. Tejero J. Ferri A. Martínez-Cob 《Agricultural Water Management》2007
In the last decade irrigation districts in the Ebro Valley of Spain have started to use database applications to enhance their management operations. Such applications often put more emphasis on administrative issues than on water management issues. A new irrigation district management software called “Ador” is presented in this paper. This database application has been designed to overcome limitations identified in an analysis of the software used in the study area. Ador can be used in irrigation districts independently of the type of irrigation system (surface, sprinkler or trickle) and the type of irrigation distribution network (open channel or pressurised). It can even be used in irrigation districts combining different types of irrigation systems and different types of irrigation distribution networks. The software can be used with minimum district information. The goals are to manage detailed information about district water management and to promote better on-farm irrigation practices. Ador is currently used to enhance management of 62 irrigation districts accounting for some 173,000 hectares in the Ebro Valley. 相似文献
53.
Elizabeth Ramírez Alan Warren Fermín Rivera Patricia Bonilla Salvador Rodríuez Arturo Calderón Ricardo Ortíz Elvia Gallegos 《Water, air, and soil pollution》1993,69(1-2):135-139
Pathogenic and non-pathogenic free-living amoebae from an activated-sludge plant were investigated. The greatest species diversity occurred in the raw, settled sewage and at the beginning of the aeration tank, whilst the lowest number of species occurred in the final sedimentation tanks. Thirteen species of free-living amoebae representing eleven genera were isolated; these included three species of Acanthamoeba (A. castellanii, A. culbertsoni and A. polyphaga), all of wich were pathogenic to mice with varying degrees of virulence. The implications for the public health risk of the presence of pathogenic free-living amoebae in activated-sludge plants are discussed. 相似文献
54.
The antioxidant capacity of butylated hydroxytoluene (BHT; 2,6-di-tert-butyl-p-cresol), propyl gallate (3,4,5-trihydroxybenzoic acid n-propyl ester), resveratrol (trans-3,4',5-trihydroxystilbene), and vitamins C (l-ascorbic acid) and E [(+)-alpha-tocopherol] was studied in chemical and biological systems. The chemical assays evaluated the capacity of these antioxidants to sequester 2,2'-azinobis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS.) and 1,1 diphenyl-2-picrylhydrazyl (DPPH.). A new colorimetric method to determine hydroxyl radical scavenging is also described. The biological tests use the eucaryotic cells of Saccharomyces cerevisiae treated with the antioxidants in the presence of the stressing agents apomorphine, hydrogen peroxide, and paraquat dichloride (methylviologen; 1,1'-dimethyl-4,4'-bipyridinium dichloride). The results in chemical systems showed that all of the antioxidants were able to significantly inhibit the oxidation of beta-carotene by hydroxyl free radicals. The assays in yeast showed that the antioxidant activity of the tested compounds depended on the stressing agent used and the mechanism of action of the antioxidant. 相似文献
55.
de Mejía EG Guzmán-Maldonado SH Acosta-Gallegos JA Reynoso-Camacho R Ramírez-Rodríguez E Pons-Hernández JL González-Chavira MM Castellanos JZ Kelly JD 《Journal of agricultural and food chemistry》2003,51(20):5962-5966
Trypsin inhibitors (TI), tannins, and lectins appear to have a role in preventing chronic diseases in humans. The genetic variability of these traits in common bean needs to be ascertained in order to increase levels through breeding. The variability of TI, tannin, and lectins was determined in five bean cultivars grown at five locations in Mexico. TI and tannins contents in colored beans that belong to the Jalisco race were higher (11.1-11.9 trypsin units inhibited (TUI)/mg and 29.0-38.1 mg catechin equivalent (CE)/g, respectively) than cultivars of the Durango race (7.9-8.3 TUI/mg and 16.8-19.9 CE/mg, respectively). Bayo Victoria, a Durango race cultivar, had three times more lectins than levels reported for soybean. Cultivar influenced TI and tannins contents (p < 0.001), whereas site affected lectins (p < 0.001). An increase in levels of TI and tannins could be enhanced through breeding. 相似文献
56.
A landscape integrated survey was carried out on the badlands area in the Upper Orcia River Valley (Siena, Italy). A methodology has been investigated to explain the soil response to dynamic and anthropic factors from an erosion hazard point of view.The Upper Orcia River Valley is one of the many neogenic basins linked to the Pliocene sea ingression, in Tuscany and all over Italy. Sediments are mainly fine silty-clay and the region is characterized by an estensive net of joints, faults and fractures due to the neotectonics in the area. The area is undergoing a fast land degradation characterized by “biancane” (domes), “calanchi” (very steep and deep gullies with a typical dendritic drainage net), gullies, several surficial erosional forms and mass movement phenomena (creeping, landslides, solifluctions and anthropic levelling).Seventeen Land Units and 46 Types were recognized according to the relationships between Elementary Landform and slope (EL), Hydrographic Net Patterns (HNP), River Bed (RB), Geomorphic Dynamics (GD), Erosion Forms (EF), Mass Movements (MM), vegetation and land use (VLU), Cultural Management systems (CM) and Morphological Sequences (MS). Lithology and soils were not taken into account as the former is to be considered almost homogeneous, while the latter are of the Entisols and Inceptisols orders (Soil Survey Staff, 1975) in the Typic Xerorthent and Xerochrept Subgroups. The soil pattern is mainly linked to geomorphic dynamics and appears extremely leopardized, every landform being characterized by various toposequences.PCA and clustering based on Euclidean distance (similarity measure) were utilized. A normalization of the variables to the standard deviation of the population was used. The previous PCA and Varimax rotation reduced the number of the variables from the original 9 to the 5 more weighing ones (1-2-5-6-7). Clusters were created to verify the Land Types groups as well as the possibility of unifying Land Units with the higher similarity level. The cluster analysis resulted in 15 groups that can well explain different land degradation patterns and which, in some cases, confirmed the Land System Analysis. The Authors came to the conclusion that multivariate analysis of landscape characteristics can only partially substitute the landscape integrated survey but can be considered a helpful means to analyse the distribution in the area of mass movements and erosion phenomena. 相似文献
57.
Antioxidant activity of the flavonoid hesperidin in chemical and biological systems 总被引:13,自引:0,他引:13
The antioxidant hesperidin, a major flavonoid in sweet orange and lemon, was evaluated using chemical and biological systems. The chemical assay evaluates the hesperidin capacity to sequester 1,1-diphenyl-2-picrylhydrazyl (DPPH*). Biological studies were done using the eukaryotic cells of superoxide-dismutase proficient and deficient strains of Saccharomyces cerevisiae treated with hesperidin and the stressing agents hydrogen peroxide or paraquat (methylviologen; 1,1'-dimethyl-4,4'-bipyridinium dichloride). Hesperidin was able to reduce significantly the level of the free radical DPPH* with similar efficacy of trolox (positive control). When the yeast cells were exposed to the flavonoid hesperidin before the stressing agents, there was a significant increase in the survival of all strains. Paraquat induced higher catalase and superoxide dismutase than did hydrogen peroxide, which only increased catalase activity. Previous addition of hesperidin to these treatments was able to reduce significantly both enzymatic levels. These observations clearly demonstrate that hesperidin provides strong cellular antioxidant protection against the damaging effects induced by paraquat and peroxide hydrogen. 相似文献
58.
M Aznar R López J F Cacho V Ferreira 《Journal of agricultural and food chemistry》2001,49(6):2924-2929
An XAD-4 extract from a 5-year-old wine from Rioja (Spain) was analyzed by aroma extract dilution analysis. Most of the odorants were quantified by GC-MS. A second extract was fractionated in an HPLC system with a C-18 semipreparative column. Fifty fractions were recovered, their alcoholic degree and pH were further adjusted to those of the wine, and those fractions that showed strong odor characteristics were further re-extracted and analyzed by GC-O and GC-MS. Reconstitution experiments were carried out to confirm the role of the odorants detected in the fractions. Fifty-eight odorants were found in the Rioja wine, 52 of which could be identified. Methyl benzoate was found to be a wine aroma constituent for the first time. The most important odorants are 4-ethylguaiacol, (E)-whiskey lactone, 4-ethylphenol, beta-damascenone, fusel alcohols, isovaleric and hexanoic acids, eugenol, fatty acid ethyl esters, and ethyl esters of isoacids, Furaneol, phenylacetic acid, and (E)-2-hexenal. Comparison among the three techniques shows good agreement and demonstrates that they are complementary. 相似文献
59.
García-Vázquez FA Ruiz S Grullón LA de Ondiz A Gutiérrez-Adán A Gadea J 《Research in veterinary science》2011,91(3):446-453
“Sperm mediated gene transfer” (SMGT) is based on the ability of sperm cells to bind exogenous DNA. The main objective of this study was to improve the production of transgenic pigs by SMGT. Taking into account that there is a lack of repeatability in studies of SMGT and that the mechanism of binding and internalization of exogenous DNA is a question that has not been solved, different factors involved in the production of transgenic animals by SMGT method were evaluated. Here we set out to: (1) evaluate the sperm capacity to bind exogenous DNA after DMSO treatment; (2) determine the location of the transgene–spermatozoa interaction; and (3) evaluate the efficiency of production of transgenic piglets by deep intrauterine artificial insemination (AI) with sperm incubated with DNA. The percentage of DNA binding was higher than 30% after 2 h of co-culture, but it was not affected by sperm treatment with DMSO (0.3% or 3%). The integrity of the sperm plasma membrane plays a critical role in DNA interaction, and altered plasma membranes facilitate interactions with exogenous DNA. DNA bound mainly to spermatozoa with reduced viability. DNA molecules were found to be mainly associated to the post-acrosomal region (61.9%). After deep intrauterine AI a total of 29 piglets were obtained, but none of them integrated the transgene. In conclusion, although it has been confirmed that DNA can associate with boar spermatozoa, the efficiency of producing transgenic pigs by AI was not confirmed by the present experiments, mainly due to a reduced DNA binding to functional spermatozoa. 相似文献
60.
Berté KA Beux MR Spada PK Salvador M Hoffmann-Ribani R 《Journal of agricultural and food chemistry》2011,59(10):5523-5527
Yerba-mate or mate? (Ilex paraguariensis A.St.-Hil., Aquifoliaceae) leaves are typically used for their stimulant, antioxidant, antimicrobial, and diuretic activity, presenting as principal components polyphenolic compounds. In this study, the objective was to develop a yerba-mate dry extract by using spray drying technology and to evaluate the dry extract antioxidant activity and chemical composition. The results obtained by means of the DPPH assay show that the extract presents an IC(50) of 2.52 mg/mL. The yerba-mate spray-dried extract presents high catalase-like activity, suggesting that it is a strong free-radical scavenger. The antioxidant activity as expressed as catalase-like activity was related to total polyphenol content. In addition, the results show that the spray-dried extract presents high polyphenol content, namely, high concentrations of caffeic acid (1.54 mg/g), 5-caffeoylquinic acid (91.40 mg/g), rutin (5.38 mg/g), and total phenolics (178.32 mg/g), which justifies its high antioxidant activity. 相似文献