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941.
The antiphospholipid syndrome is an autoimmune disease characterised by recurrent arterial or venous thrombosis, pregnancy morbidity and the persistence of positive antiphospholipid antibodies. Many other clinical manifestations may occur including heart valve disease, livedo reticularis, thrombocytopenia and neurological manifestations such as migraine and seizures. We review a number of other manfestations including stenotic lesions, coronary artery disease and accelerated atherosclerosis, skeletal disorders and the concept of seronegative antiphospholipid syndrome. 相似文献
942.
Antonia Spadafora ;Silvia Mazzuca ;Francesca Fiorella Chiappetta ;Attilio Parise ;Enzo Perri ;AnnaMafia Innocenti 《中国农业科学(英文版)》2008,7(6):703-712
Olive fruits are seriously deteriorated by pre and postharvest damage due to the attack of insects, such as Bactrocera olaea, which strongly alters the quality of olives. Defence response in olive fruits injured both by pathogens and by mechanical damages has been associated with the enzyme β-glucosidase, which specifically hydrolyses oleuropein, producing highly reactive aldehyde molecules. In situ detection of ~-glucosidase activity in olive fruit tissues following injury, which simulates Bactrocera oleae punctures, is reported. The assay was performed in two cultivars showing different degrees of susceptibilities to fly infestation. In both cultivars, the histochemical assay for β-glucosidase showed that within 20 min after the injury, a strong ~-glucosidase activity could be observed in the damaged tissues. Thereafter a progressive enzyme inactivation occurred starting from tissues around the boundary of the injury with decrease of the enzyme activity and stopped after 3 h. Whereas the mass of active cells reached a distance of (300±50) μm from the edge of the injury. Biochemical analyses showed that in extracts of the injured fruit, β-glucosidase activity rapidly increased within 20 min from injury, thereafter decreasing and reaching values comparable with those in intact fruits. Following puncture, the oleuropein contents did not change significantly in the high susceptibility cultivar, whereas it rapidly decreased in the cultivar showing low susceptibility. The results strongly suggest that olive fruits susceptible towards fly infestation could be related to the ability of the oleuropein-degrading-β-glucosidase to produce the highly reactive molecules in the damaged tissues. As a consequence of puncture, high level of peroxidase activity was detected. This feature also suggested that this enzyme could play a key role in the defence response against insect injuries. 相似文献
943.
Oleuropein-Specific-β-Glucosidase Activity Marks the Early Response of Olive Fruits (Olea europaea) to Mimed Insect Attack 总被引:1,自引:0,他引:1
Antonia Spadework Silvia Mazzuca Francesca Fiorella Chiappetta Attilio Parise Enzo Perri Anna Maria Innocenti 《中国农业科学(英文版)》2008,7(6)
Olive fruits are seriously deteriorated by pre and postharvest damage due to the attack of insects, such as Bactrocera olaea, which strongly alters the quality of olives. Defence response in olive fruits injured both by pathogens and by mechanical damages has been associated with the enzyme β-glucosidase, which specifically hydrolyses oleuropein, producing highly reactive aldehyde molecules. In situ detection of β-glucosidase activity in olive fruit tissues following injury, which simulates Bactrocera oleae punctures, is reported. The assay was performed in two cultivars showing different degrees of susceptibilities to fly infestation. In both cultivars, the histochemical assay for β-glucosidase showed that within 20 min after the injury, a strong β-glucosidase activity could be observed in the damaged tissues. Thereafter a progressive enzyme inactivation occurred starting from tissues around the boundary of the injury with decrease of the enzyme activity and stopped after 3h. Whereas the mass of active celsreached a distance of (300±50)μm from the edge of the injury. Biochemical analyses showed that in extracts of the injured fruit, β-glucosidase activity rapidly increased within 20 min from injury, thereafter decreasing and reaching values comparable with those in intact fruits. Following puncture, the oleuropein contents did not change significantly in the high susceptibility cultivar, whereas it rapidly decreased in the cultivar showing low susceptibility. The results strongly suggest that olive fruits susceptible towards fly infestation could be related to the ability of the oleuropein-degrading-β-glucosidase to produce the highly reactive molecules in the damaged tissues. As a consequence of puncture, high level of peroxidase activity was detected. This feature also suggested that this enzyme could play a key role in the defence response against insect injuries. 相似文献
944.
945.
Responses to divergent selection for cob color in maize 总被引:1,自引:1,他引:0
Previous studies showed that in materials derived from maize (Zea mays L.) single cross A632 × Mu195 there is association between agronomic traits and cob color (affected by P1 gene). Objectives of this study were to evaluate the responses to divergent selection for cob color in F2-Syn 0 (obtained by selfing A632 × Mu195), estimate the genetic parameters of the involved putative quantitative trait loci
(QTL), and evaluate the responses to divergent selection for cob color in A632 and Mu195 backgrounds. The populations selected
in F2-Syn 0 for red (R0) or white cob (W0) were tested in four trials. Differences between R0 and W0 were found for grain yield
(85.0 vs. 75.0 g/plant) and other traits; most of these differences were related to leaf number/plant. Then, population F2-Syn 1, derived after one random mating generation, was divergently selected for cob color, thus producing R1 and W1. Populations
R0, W0, R1, and W1 were tested in two trials, allowing the estimate of genetic effects and recombination frequencies for putative
QTL of several traits. Finally, a divergent selection for cob color was conducted in segregating materials of A632 and Mu195
backgrounds. The two pairs of selected populations were compared in two trials; the responses were similar to those detected
by comparing R0 and W0. We conclude that divergent selection for cob color in F2-Syn 0 is effective for several traits, that such responses are due to putative QTL linked to P1, and that selection is also effective in different genetic backgrounds. 相似文献
946.
Johann Sölkner Heinrich Grausgruber Ally Mwai Okeyo Peter Ruckenbauer Maria Wurzinger 《Euphytica》2008,161(1-2):273-282
Breeding objectives always involve consideration of multiple traits, even in situations where output of a single trait is
dominant. We review literature dealing with formal definition of breeding objectives. Involvement of farmers in the process
of setting up breeding objectives is also considered. In the optimal selection index, the relative importance of a trait is
scaled by its economic value, derived as marginal profit related to a change in expression of defined size. Normative approaches
to derive economic values use partial derivatives of a profit equation with respect to the traits involved or model the bio-economic
system with various techniques. The theory is well developed and includes consideration of non-linear profit functions and
traits with an intermediate optimum. It is frequently applied in animal breeding. In dairy cattle breeding, a major change
of focus from traits related to output (i.e., milk yield) to traits related to cost of input (health, fertility, feed efficiency)
has taken place recently. Plant breeders find the concept of deriving relative economic weights of traits difficult to apply
and often replace the optimal index by restricted or desired gains indices. A change of paradigms similar to that in cattle
breeding seems advisable. Participatory approaches to evaluate the relative importance of traits are more frequently applied
in plant breeding than in animal breeding. We review two studies, dealing with methods of acquiring information about selection
criteria of farmers planting maize in the Ethiopian highlands and of pastoralists keeping cattle in Uganda, in detail. 相似文献
947.
Maria Suely Pagliarini Claudicéia Risso-Pascotto Alice Maria de Souza-Kaneshima Cacilda Borges do Valle 《Euphytica》2008,164(1):181-187
Sexuality is correlated with diploidy and apomixis with polyploidy in the Brachiaria genus. Brachiaria ruziziensis is a key species in Brachiaria breeding due to its obligate sexuality and intrinsic agronomic qualities. Interspecific crosses in the genus became feasible
only when a few diploid accessions of B. ruziziensis were artificially tetraploidized and remained sexual. Hybridization has been done since, using natural tetraploid apomictic
accessions of B. brizantha or B. decumbens as pollen donors. Twenty two accessions of B.
ruziziensis from the Embrapa Beef Cattle germplasm collection (Campo Grande, MS, Brazil) were cytologically analyzed: 16 are natural
diploids (2n = 2x = 18) and six are artificially induced tetraploids (2n = 4x = 36). The meiotic behavior in the 16 diploid accessions varied. The mean of meiotic abnormalities per accession ranged from
zero to 24.46%. Meiotic behavior in the induced tetraploid accessions also varied with the mean of meiotic abnormalities ranging
from 5.20% to 54.71%. The most common abnormalities observed in both the diploid and the tetraploid accessions, were those
related to irregular chromosome segregation. In one tetraploid accession, with a high frequency of those, other irregularities
involving chromosome orientation at metaphase plate and chromosome convergence to the poles, a meiotic mutation known as divergent spindle, were recorded. Meiotic behavior should be considered in selecting potential genitors for breeding. 相似文献
948.
Chemical composition and antimicrobial activity of Momordica charantia seed essential oil 总被引:1,自引:0,他引:1
The essential oil obtained from the seeds of Momordica charantia was analyzed by GC/MS. Twenty-five components, representing 90.9% of the oil, were identified. The main constituents were trans-nerolidol, apiole, cis-dihydrocarveol and germacrene D. Furthermore, the oil was tested for its antibacterial and antifungal activities. Staphylococcus aureus was found to be the most sensitive microorganism with MIC values <500 microg/ml. 相似文献
949.
950.