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71.
Jatindra N. Bhakta Y. Munekage K. Ohnishi B. B. Jana J. L. Balcazar 《Water, air, and soil pollution》2014,225(10):1-10
The contamination of hazardous metal(loid) is one of the serious environmental and human health risks. This study isolated a total of 40 cadmium (Cd)- and arsenic (As)-resistant bacterial isolates from coastal sediments by pour plate technique using tryptic soy agar supplemented with Cd or As (50 mg l?1) for use as metal(loid) bioremediation agents. Out of 40, 4 isolates, RCd3, RCd6, RAs7, and RAs10, showed a relatively higher growth rate in Cd- or As-supplemented culture media which were selected for further study. The selected isolates showed a high minimum inhibitory concentration (60–400 mg l?1 for Cd and 400–2200 mg l?1 for As), which demonstrated their remarkable Cd and As resistance capabilities. The metal(loid) removal efficiencies (0.032–0.268 μg Cd h?1 mg?1 and 0.0003–0.0172 μg As h?1 mg?1 [wet weight cell]) of selected isolates indicated their greater magnitude in absorbing Cd compared to As from water. Phylogenetic analysis of the 16S rDNA sequences revealed that isolates RCd3, RCd6, RAs7, and RAs10 were closely related to Acinetobacter brisouii, Pseudomonas abietaniphila, Exiguobacterium aestuarii, and Planococcus rifietoensis, respectively. Because of high Cd and As resistance and removal efficiency, the selected isolates can survive in a high metal(loid)-contaminated environment and could be a potential tool for bioremediation of high metal(loid)-contaminated effluents to protect the aquatic environment. 相似文献
72.
Three systems of carp (Cyprinus carpio) culture (live food system, manured system, and control system) were used to examine environmentally dependent life history characteristics of zooplankton, Moina micrura. Twelve culture tubes with one neonate of M. micrura per tube and covered by nylon bolting cloth of 75 μm mesh size were suspended in situ in each culture system. Each culture tube was examined daily to evaluate life history patterns. Time to first reproduction ranged from 4 to 7 days in the control and manured systems and 3 to 5 days in the live food system. Mean longevity, net reproductive rate, average generation time, as well as total offspring production per female, were distinctly higher for the live food system than for the manured or control systems. Interactions between chemical oxygen demand, dissolved oxygen, phosphate levels and primary productivity resulting in optimal conditions were responsible for large variations in life history characteristics of M. micrura among the culture systems. 相似文献
73.
AnnaLotta Schiller Vestergren Sofia Trattner Jinfeng Pan Pernilla Johnsson Afaf Kamal-Eldin Eva Brännäs Ali A. Moazzami Jana Pickova 《Aquaculture International》2013,21(4):843-859
Sesamin (S) is a known lipid modulator and has been shown to increase the conversion of α-linolenic acid (ALA) to docosahexaenoic acid in rainbow trout (Oncorhynchus mykiss) fed vegetable oil mixtures including linseed oil. In this study, we evaluated the effects of S supplementation in linseed oil-based diets, content of α- and γ-tocopherols, fatty acid (FA) composition, as well as the gene expression of lipid-related genes. Fish with an average weight of 36.5 g were fed different combinations of commercial linseed oil (LO), purified linseed oil triacylglycerols (TAG) with polar fraction removed and a mixed linseed-sunflower oil (6:4 v/v) (MO). S was added at 0.58 g 100?1g feed and fed to the fish for a period of 58 days. Expression of PPARα was downregulated in white muscle of fish fed S containing diets (P < 0.05). The expression of PPARβ1A was not affected by S supplementation except where TAG oil was used. The expression of PPARβ1A declined significantly in TAG + S fed group (P < 0.05), which indicates that some minor compounds in linseed oil might suppress the effect of S on the expression of PPARβ1A. The expression of PPARγ(long) declined in LO + S and MO + S fed group (P < 0.05). The β-oxidation-related genes CPT1 and ACO were upregulated by vegetable oils compared to fish oil. S decreased percentage of ALA in white muscle of fish fed LO + S (P < 0.05). The increased desaturation index and the decreased ALA levels suggest that S may increase the biosynthesis of highly unsaturated FA in rainbow trout. 相似文献
74.
Denoeud F Henriet S Mungpakdee S Aury JM Da Silva C Brinkmann H Mikhaleva J Olsen LC Jubin C Cañestro C Bouquet JM Danks G Poulain J Campsteijn C Adamski M Cross I Yadetie F Muffato M Louis A Butcher S Tsagkogeorga G Konrad A Singh S Jensen MF Cong EH Eikeseth-Otteraa H Noel B Anthouard V Porcel BM Kachouri-Lafond R Nishino A Ugolini M Chourrout P Nishida H Aasland R Huzurbazar S Westhof E Delsuc F Lehrach H Reinhardt R Weissenbach J Roy SW Artiguenave F Postlethwait JH Manak JR Thompson EM 《Science (New York, N.Y.)》2010,330(6009):1381-1385
Genomes of animals as different as sponges and humans show conservation of global architecture. Here we show that multiple genomic features including transposon diversity, developmental gene repertoire, physical gene order, and intron-exon organization are shattered in the tunicate Oikopleura, belonging to the sister group of vertebrates and retaining chordate morphology. Ancestral architecture of animal genomes can be deeply modified and may therefore be largely nonadaptive. This rapidly evolving animal lineage thus offers unique perspectives on the level of genome plasticity. It also illuminates issues as fundamental as the mechanisms of intron gain. 相似文献
75.
The effects of combinations of Hg, As, Pb, Cu, Cd, and Cr on the variables of Cuscuta reflexa Roxb. in natural condition were studied. All of the combinations of heavy metals tested decreased Hill reaction activity, chlorophyll and protein contents and increased tissue permeability over control values. The effects were best visible with the treatments of (As + Cd + Pb + Hg + Cu + Cr) and (As + Cd + Pb + Hg + Cu), followed by (As + Cd + Pb + Hg), (As + Cd + Pb), and (As + Cd). The degree of inhibition or increase by combinations of heavy metals is much higher due to synergism as the observed effects exceed the summed amount. The general order of sensitivity was As > Cd > Pb > Hg > Cu > Cr (absolute metal concentration). 相似文献
76.
Deoxynivalenol oligoglycosides: new "masked" fusarium toxins occurring in malt, beer, and breadstuff
M Zachariasova M Vaclavikova O Lacina L Vaclavik J Hajslova 《Journal of agricultural and food chemistry》2012,60(36):9280-9291
The co-occurrence of deoxynivalenol-3-glucoside with its parent toxin, deoxynivalenol, has been recently documented in many cereal-based foods, especially in those produced by enzyme-catalyzed processes. The presence of this masked mycotoxin in the human diet has become an issue of health concern, mainly because of its assumed bioavailability. A selective immunoaffinity-based preconcentration strategy, followed by ultrahigh-performance liquid chromatography coupled with high-resolution orbitrap mass spectrometry, revealed that, in addition to the most common deoxynivalenol-3-glucoside, also oligoglycosylated deoxynivalenols with up to four bound hexose units were present in cereal-based products. The structure, origination, and fate of these deoxynivalenol conjugates during malt/beer production and bread baking have been thoroughly investigated. Special attention has been paid to the changes of deoxynivalenol conjugates enabled by industrial glycosidase-based enzymatic preparations. To the authors' best knowledge, this is the first study documenting the complexity of masked deoxynivalenol issue. 相似文献
77.
Havlová P Lancová K Vánová M Havel J Hajslová J 《Journal of agricultural and food chemistry》2006,54(4):1353-1360
Protection of barley grain against contamination by fungi such as Fusarium spp., particularly by those producing mycotoxins, secondary metabolites with adverse health effects, is of principal importance. Fungicides applied immediately after full heading of spring barley is one method of direct protection. In this work, extensive two-year field experiments combined with a detailed chemical laboratory analysis (barley and malt) were performed with the aim to study the effect of previous crops, different fungicides, and other conditions on the selected barley and malt quality parameters (content of beta-glucans, pentosans, oxalic acid, deoxynivalenol, and gushing), while the main task was to follow the effect of the fungicide (used as a treatment to protect against pathogens, mostly Fusarium) on changes of the chemical composition in barley and malt, and gushing. It was found that the relationship between the studied factors and the parameters usually applied to the evaluation of barley and malt quality is quite complex and not straightforward. The responses show typical features of a multifactorial influence with both positive and negative correlations resulting in a decrease or increase in grain quality (concentrations of beta-glucans, pentosans, deoxynivalenol, and other studied parameters). The role of previous crops was also found to be important. The fungicides should be applied at the time of heading but not at the very beginning of this period. 相似文献
78.
Konečná H Müller L Dosoudilová H Potěšil D Buršíková J Sedo O Márová I Zdráhal Z 《Journal of agricultural and food chemistry》2012,60(10):2418-2426
Two-dimensional gel electrophoresis in combination with mass spectrometry has already been applied successfully to study beer proteome. Due to the abundance of protein Z in beer samples, prefractionation techniques might help to improve beer proteome coverage. Proteins from four lager beers of different origins were separated by two-dimensional electrophoresis (2-DE) followed by tandem mass spectrometric analysis. Initially 52 proteins mostly from Hordeum vulgare (22 proteins) and Saccharomyces species (25 proteins) were identified. Preparative isoelectric focusing by OFFGEL Fractionator was applied prior to 2-DE to improve its resolution power. As a result of this combined approach, a total of 70 beer proteins from Hordeum vulgare (30 proteins), from Saccharomyces species (31 proteins), and from other sources (9 proteins) were identified. Of these, 37 proteins have not been previously reported in beer samples. 相似文献
79.
Jana Řepková Antonín Dreiseitl Pavel Lízal Zdeňka Kyjovská Kateřina Teturová Radka Psotková Ahmed Jahoor 《Euphytica》2006,151(1):23-30
Summary Four newly detected accessions of wild barley (Hordeum
vulgare ssp. spontaneum) resistant to powdery mildew caused by Blumeria
graminis f. sp. hordei were studied with the aim of finding the number of genes/loci conferring the resistance of individual accessions, the type of inheritance of the genes and their relationships to the Mla locus. F2 populations after crosses between the winter variety ‘Tiffany’ and four wild barley accessions and use of microsatellite DNA markers were focused on the identification of individual resistance genes/loci by means of their chromosomal locations. In PI466495, one locus conferring powdery mildew resistance was identified in highly significant linkage with the marker Bmac0213. This location is consistent with the known locus Mla on chromosome 1HS. In the other three accessions the resistance was determined by two independent loci. In PI466197, PI466297 and PI466461, one locus was identified on chromosome 1HS and three new loci were revealed on chromosomes 2HS (highly significant linkage with Bmac0134), 7HS (highly significant linkage with Bmag0021) and 7HL (significant linkage with EBmac0755). Our prospective aim is identification of further linked DNA markers and the exact location of the resistance genes on the barley chromosomes. 相似文献
80.
Polyurethane-based side-chain cholesteric liquid crystalline polymers (ChLCPs) with variable clearing temperatures were synthesized
in a two-step reaction. The chemical structures of ChLCPs were confirmed by FT-IR and 1H-NMR spectroscopy. The mesogenic properties and phase transition behavior were investigated by means of differential scanning
calorimetry (DSC), polarizing optical microscopy (POM), and X-ray diffraction measurements. The DSC studies show that the
melting temperature and isotropic transition temperature of the ChLCPs increased with the weight percentage of cholesterol
in the polymer. POM shows that the ChLCPs had a distinct spherulite structure that melted at about 140 °C, and these results
are consistent with those of the DSC studies. The thermogravimetric studies show that the ChLCPs were stable up to 200 °C,
though there was a reduction in the thermal stability as the weight proportion of cholesterol and glycerol in the polymer
increased. 相似文献