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121.
Saguez J Dubois F Vincent C Laberche JC Sangwan-Norreel BS Giordanengo P 《Pest management science》2006,62(12):1150-1154
Four chitinase inhibitors, cyclo-(Proline-Tyrosine), cyclo-(Histidine-Proline), allosamidin and psammaplin A, were selected for in vitro feeding experiments with the peach-potato aphid, Myzus persicae (Sulzer), under controlled photoperiod and temperature conditions. Artificial diets were used to provide chitinase inhibitors at 10, 50 and 100 microg mL(-1) to M. persicae. Except for cyclo-(Proline-Tyrosine), which did not modify aphid demographic parameters, chitinase inhibitors induced differential aphicidal effects on M. persicae. At all doses, cyclo-(Histidine-Proline) induced significant effects affecting daily fecundity, intrinsic rate of natural increase (r(m)) and doubling time of population. When compared with the control diet, allosamidin decreased nymph survival and daily fecundity, increasing the doubling time of population from 1 to 1.5 days. Psammaplin A was the most toxic inhibitor when delivered via artificial diet, as it induced the death of all aphids reared at 50 and 100 microg mL(-1). The results demonstrate the potential use of chitinase inhibitors as aphid management tools. 相似文献
122.
123.
Franka Mlikota Gabler Julien Mercier J.I. Jiménez J.L. Smilanick 《Postharvest Biology and Technology》2010,55(2):78-84
An integrated approach was evaluated that combined biological and chemical fumigation of table grapes to control postharvest gray mold caused by Botrytis cinerea. After fumigation of the grapes with ozone or sulfur dioxide during pre-cooling, the fruit were then exposed to continuous biofumigation by the volatile-producing fungus Muscodor albus during storage. Biofumigation was provided by in-package generators containing a live grain culture of the fungus. This grain formulation of M. albus survived the initial ozone or sulfur dioxide fumigation, but sulfur dioxide reduced its production of isobutyric acid, an indicator of the production of antifungal volatiles. Gray mold incidence was reduced among inoculated ‘Autumn Seedless’ grapes from 91.7 to 19.3% by 1 h fumigation with 5000 μL L?1 ozone, and further reduced to 10.0% when ozone fumigation and M. albus biofumigation were combined. The natural incidence of gray mold among organically grown ‘Thompson Seedless’ grapes after 1 month of storage at 0.5 °C was 31.0%. Ozone fumigation and M. albus biofumigation reduced the incidence of gray mold to 9.7 and 4.4, respectively, while the combined treatment reduced gray mold incidence to 3.4%. The use of commercial sulfur dioxide pads reduced the incidence to 1.1%. The combination of ozone and M. albus controlled decay significantly, but was less effective than the standard sulfur dioxide treatments. Although less effective than sulfur dioxide treatment, ozone and M. albus controlled decay significantly, and could be alternatives to sulfur dioxide, particularly for growers complying with organic production requirements. 相似文献
124.
Context
In response to waterlogging, pedunculate oak is known to develop adventitious roots and hypertrophied lenticels. However, to date, a link between these adaptations and the ability to maintain net CO2 assimilation rates and growth has not been demonstrated.Aims
The aim of this study was to explore the cause–effect relationship between the ability to form morphological adaptations (hypertrophied lenticels and adventitious roots) and the capacity to maintain high assimilation rate and growth.Methods
The occurrence of morphological adaptations and the parameters of photosynthesis were monitored over 20 days of waterlogging in 5-week-old pedunculate oak seedlings presenting similar morphological development.Results
Based on the development or not of morphological adaptations, the following three categories of responses were identified: development of hypertrophied lenticels and adventitious roots, development of hypertrophied lenticels alone, and the lack of development of adaptive structures. These categories, ranked in the order given, corresponded to decreasing levels of initial net CO2 assimilation rate growth and photosynthesis parameters observed during waterlogging.Conclusion
We observed a two-way cause–effect relationship between the capacity to form adaptive structures and the assimilation rate. Indeed, the initial assimilation rate determined the occurrence of hypertrophied lenticels and growth during stress, and then the development of morphological adaptations enhanced the ability to maintain assimilation levels during the stress. 相似文献125.
126.
127.
Pezet R Perret C Jean-Denis JB Tabacchi R Gindro K Viret O 《Journal of agricultural and food chemistry》2003,51(18):5488-5492
Delta-viniferin is a resveratrol dehydrodimer, an isomer of epsilon-viniferin. This compound has been reported as a molecule produced in vitro by the oxidative dimerization of resveratrol by plant peroxidases or fungal laccases. It was also recently identified in wines and in grape cell cultures. We have now identified this dimer by NMR, high-performance liquid chromatography-diode array detection (HPLC-DAD), and HPLC-mass spectrometry (MS) in grapevine leaves infected by Plasmopara viticola (downy mildew) or UV-C irradiated. Its concentration was higher than that of epsilon-viniferin and constitutes one of the most important phytoalexins derived from resveratrol. 相似文献
128.
Julien Ruelle Jacques Beauchêne Hiroyuki Yamamoto Bernard Thibaut 《Wood Science and Technology》2011,45(2):339-357
Growth strains were measured in situ in nine trees of three species from a French Guiana tropical rainforest in a clearly
active verticality restoration process. The aim was to detect tension wood within the samples. Wood specimens were cut in
the vicinity of the growth strain measurements in order to determine the microfibril angle and some mechanical and physical
properties. As suspected, tensile growth strain was much higher in tension wood zones, as shown by the slightly higher longitudinal
modulus of elasticity. Conversely, tension wood showed reduced compression strength. Longitudinal shrinkage was much higher
in tension wood than in opposite wood. Clear relationships between the microfibril angle and longitudinal properties were
noted in comparison (i) with those observed in gymnosperm compression wood and (ii) with expected relationships from the organization
of wood fibres cell wall structure. 相似文献
129.
Julien Guevar Petra Hug Felix Giebels Alexane Durand Vidhya Jagannathan Tosso Leeb 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2020,34(1):289-293
A 2-year-old male domestic shorthair cat was presented for a progressive history of abnormal posture, behavior, and mentation. Menace response was absent bilaterally, and generalized tremors were identified on neurological examination. A neuroanatomical diagnosis of diffuse brain dysfunction was made. A neurodegenerative disorder was suspected. Magnetic resonance imaging findings further supported the clinical suspicion. Whole-genome sequencing of the affected cat with filtering of variants against a database of unaffected cats was performed. Candidate variants were confirmed by Sanger sequencing followed by genotyping of a control population. Two homozygous private (unique to individual or families and therefore absent from the breed-matched controlled population) protein-changing variants in the major facilitator superfamily domain 8 (MFSD8) gene, a known candidate gene for neuronal ceroid lipofuscinosis type 7 (CLN7), were identified. The affected cat was homozygous for the alternative allele at both variants. This is the first report of a pathogenic alteration of the MFSD8 gene in a cat strongly suspected to have CLN7. 相似文献