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991.
About 30% of the potato plants from a (Solanum tuberosum × S. berthaultii) × S. tuberosum backcross population had chlorotic, malformed leaves; but a gradation in symptom severity suggested regulation by more than
one gene. The study was undertaken to determine whether this was the case, whether any genes previously reported to control
chlorosis in potato were involved, and to see how symptoms were related to effects on chlorophyll content. Testing for quantitative
trait loci indicated major control by a single recessive gene on chromosome 1, close to one or more loci that have been reported
to produce chlorosis in tomato, but distinct from similar genes previously identified in potato. The proposed symbol for the
potato gene that confers phenotype with chlorotic and malformed leaves is cml (chlorotic and malformed leaves). The effects of this gene appeared to be accentuated by a second gene, located on chromosome
12. Chlorotic plants showed a 50% decrease in chlorophyll b level in the affected parts of leaves. It is concluded that cml is different from previously reported genes for chlorosis in potato, that at least one other gene modifies the intensity
of symptom expression, and that the observed chlorosis is produced through effects on chlorophyll b level. 相似文献
992.
Busetto ML Moretti VM Moreno-Rojas JM Caprino F Giani I Malandra R Bellagamba F Guillou C 《Journal of agricultural and food chemistry》2008,56(8):2742-2750
Fatty acid composition and stable isotope ratios of carbon (delta(13)C) and nitrogen (delta(15)N) were determined in muscle tissue of turbot (Psetta maxima). The multivariate analysis of the data was performed to evaluate their utility in discriminating wild and farmed fish. Wild (n=30) and farmed (n=30) turbot of different geographical origins (Denmark, The Netherlands, and Spain) were sampled from March 2006 to February 2007. The application of linear discriminant analysis (LDA) and soft independent modeling of class analogy (SIMCA) to analytical data demonstrated the combination of fatty acids and isotopic measurements to be a promising method to discriminate between wild and farmed fish and between wild fish of different geographical origin. In particular, IRMS (Isotope Ratio Mass Spectrometry) alone did not permit us to separate completely farmed from wild samples, resulting in some overlaps between Danish wild and Spanish farmed turbot. On the other hand, fatty acids alone differentiated between farmed and wild samples by 18:2n-6 but were not able to distinguish between the two groups of wild turbot. When applying LDA isotope ratios, 18:2n-6, 18:3n-3, and 20:4n-6 fatty acids were decisive to distinguish farmed from wild turbot of different geographical origin, while delta(15)N, 18:2n-6, and 20:1n-11 were chosen to classify wild samples from different fishing zones. In both cases, 18:2n-6 and delta(15)N were determinant for classification purposes. We would like to emphasize that IRMS produces rapid results and could be the most promising technique to distinguish wild fish of different origin. Similarly, fatty acid composition could be used to easily distinguish farmed from wild samples. 相似文献
993.
Audrius Menkis Aistė Povilaitienė Adas Marčiulynas Jūratė Lynikienė Artūras Gedminas Diana Marčiulynienė 《Scandinavian Journal of Forest Research》2019,34(1):26-32
The horse chestnut leaf-miner (Cameraria ohridella Deschka & Dimi?, Lepidoptera, Gracillariidae) is an invasive pest causing extensive damage to leaves of the horse-chestnut (Aesculus hippocastanum L.) in Europe. In Lithuania, C. ohridella invaded in 2002 causing wilting, browning and premature fall of A. hippocastanum leaves. The aim was to get a better understanding of possible linkages between foliar fungal communities and leaf-miner damage in A. hippocastanum. Leaves of A. hippocastanum, differentially damaged by C. ohridella, were collected in 10 sites in Lithuania. The fungal communities were described through DNA isolation and amplification using an ITS rRNA marker and Ion Torrent-sequencing. Clustering of 214,897 high-quality sequences resulted in 1017 non-singleton fungal taxa, among which Aureobasidium pullulans (28.2% of all fungal sequences), Endoconidioma populi (27.7%), Phoma fungicola (11.3%), Cladosporium ramotenellum (7.6%) and Cryptococcus sp. 2185_4 (5.0%) were most common. Correspondence analysis showed that fungal communities from heavily and slightly damaged leaves were largely intermingled, showing that in both types of samples fungal communities were similar. In conclusion, the study demonstrated that the phyllosphere of A. hippocastanum is inhabited by a high diversity of fungal species, the majority of which constitute generalist endophytes, epiphytes and saprotrophic fungi. The occurrence of common phyllosphere fungi was unrelated to the degree of damage by C. ohridella. 相似文献
994.
Gopčević Kristina Grujić Slavica Arsenijević Jelena Karadžić Ivanka Izrael-Živković Lidija Maksimović Zoran 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(2):179-184
Plant Foods for Human Nutrition - Satureja kitaibelii Wierzb. ex Heuff. has a great importance in Serbian ethnopharmacology/herbal traditional medicine, as well as a flavoring food additive.... 相似文献
995.
996.
Algirdas Augustaitis Ingrida Augustaitienė Almantas Kliučius Gintaras Pivoras Dalia Šopauskienė Raselė Girgždienė 《European Journal of Forest Research》2010,129(3):431-441
The multiple-stressor effects of air pollution, nutrient and water availability are the key issues of present forest ecosystem
research. However, too little is known about the seasonal effect of pollutants on tree crown defoliation and their interaction
with changes in climate. Therefore, data on seasonal variation in air pollution, including surface ozone, deposition of acidifying
compounds and meteorological conditions, were tested against pine defoliation to identify the periods when the effect of the
considered contaminants is most pronounced. The findings of the study revealed that a higher level of air concentrations of
acidifying pollutants and their deposition was observed during the dormant period, with the exception of only ΣNH4+ air concentrations and their monthly deposition. An increase in precipitation over the vegetation period and mean monthly
temperature from September to December, as well as a decrease in temperature and precipitation over the remaining months of
the dormant period represented the climate change condition over the 14-year period in the observed region. Detected changes
in the considered parameters during the dormant period were found to be most significant to changes in pine crown defoliation.
Therefore, we concluded that climate changes, if they occur by the detected scenarios, should mitigate the negative effect
of air pollutants and acid deposition on pine crown condition. 相似文献
997.
Ladislav Cséfalvay Gabriele Di Gaspero Karel Matouš Diana Bellin Benedetto Ruperti Julie Olejníčková 《European journal of plant pathology / European Foundation for Plant Pathology》2009,125(2):291-302
Plasmopara viticola is an economically important pathogen of grapevine. Early detection of P. viticola infection can lead to improved fungicide treatment. Our study aimed to determine whether chlorophyll fluorescence (Chl-F)
imaging can be used to reveal early stages of P. viticola infection under conditions similar to those occurring in commercial vineyards. Maximum (FV/FM) and effective quantum yield of photosystem II (ΦPSII) were identified as the most sensitive reporters of the infection. Heterogeneous distribution of FV/FM and ΦPSII in artificially inoculated leaves was associated with the presence of the developing mycelium 3 days before the occurrence
of visible symptoms and 5 days before the release of spores. Significant changes of FV/FM and ΦPSII were spatially coincident with localised spots of inoculation across the leaf lamina. Reduction of FV/FM was restricted to the leaf area that later yielded sporulation, while the area with significantly lower ΦPSII was larger and probably reflected the leaf parts in which photosynthesis was impaired. Our results indicate that Chl-F can
be used for the early detection of P. viticola infection. Because P. viticola does not expand systemically in the host tissues and the effects of infection are localised, Chl-F imaging at high resolution
is necessary to reveal the disease in the field. 相似文献
998.
Irena Mavrič Pleško Mojca Viršček Marn Saša Širca Gregor Urek 《European journal of plant pathology / European Foundation for Plant Pathology》2009,123(3):261-268
In 2003, Raspberry bushy dwarf virus was found for the first time in grapevine. Since this was the first report of a non-Rubus natural host, information about it is sparse. During this study the grapevine isolates were characterised biologically, serologically
and genetically and compared with known information about Rubus isolates. Infected plant material was used for mechanical inoculation of test plants, and for serological characterisation
with monoclonal antibodies. Most of RNA 2 was sequenced and compared with other sequences from the database. Grapevine isolates
infected Chenopodium murale systemically, which is not known for raspberry isolates. They were differentiated from Slovenian raspberry isolates with
three monoclonal antibodies using TAS-ELISA. Phylogenetic analyses clustered grapevine isolates separately from raspberry
isolates. Additionally, the virus was detected using nested RT-PCR in Longidorus juvenilis nematodes collected in an infected vineyard. Grapevine isolates of RBDV are distinct from raspberry isolates. 相似文献
999.
Vesna Ilić Zoran Šaponjić Vesna Vodnik Darka Mihailović Petar Jovančić Jovan Nedeljković Maja Radetić 《Fibers and Polymers》2009,10(5):650-656
The aim of this study was to examine the influence of dyeing on antibacterial efficiency of corona activated polyamide and polyester fabrics loaded with colloidal Ag nanoparticles as well as the influence of the presence of Ag nanoparticles on the color change of dyed fabrics. C.I. Acid Green 25 and C.I. Disperse Blue 3 were used for dyeing of polyamide fabrics and C.I. disperse violet 8 for polyester fabrics. The color change of polyamide fabrics depends on the dye type, which was generally lower compared to polyester fabrics. Antibacterial efficiency of Ag loaded fabrics was tested against Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Escherichia coli. Corona activated polyester and polyamide fabrics showed excellent antibacterial efficiency independently of order of dyeing and Ag loading. The morphology of fibers loaded with Ag nanoparticles was assessed by SEM and atomic absorption spectroscopy for elemental analysis. 相似文献
1000.
Faganeli J Mohar B Kofol R Pavlica V Marinšek T Rozman A Kovač N Vuk AŠ 《Marine drugs》2010,8(9):2480-2492
The key organic constituents of marine macroaggregates (macrogels) of prevalently phytoplankton origin, periodically occurring in the northern Adriatic Sea, are proteins, lipids and especially polysaccharides. In this article, the reactivity of various macroaggregate fractions in relation to their composition in order to decode the potentially »bioavailable« fractions is summarized and discussed. The enzymatic hydrolysis of the macroaggregate matrix, using α-amylase, β-glucosidase, protease, proteinase and lipase, revealed the simultaneous degradation of polysaccharides and proteins, while lipids seem largely preserved. In the fresh surface macroaggregate samples, a pronounced degradation of the α-glycosidic bond compared to β-linkages. Degradation of the colloidal fraction proceeded faster in the higher molecular weight (MW) fractions. N-containing polysaccharides can be important constituents of the higher MW fraction while the lower MW constituents can mostly be composed of poly- and oligosaccharides. Since the polysaccharide component in the higher MW fraction is more degradable compared to N-containing polysaccharides, the higher MW fraction represents a possible path of organic nitrogen preservation. Enzymatic hydrolysis, using α-amylase and β-glucosidase, revealed the presence of α- and β-glycosidic linkages in all fractions with similar decomposition kinetics. Our results indicate that different fractions of macroaggregates are subjected to compositional selective reactivity with important implications for macroaggregate persistence in the seawater column and deposition. 相似文献