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81.
Amandine Cunty Bruno Legendre Pauline de Jerphanion Virginie Juteau Aurélie Forveille Jean-François Germain Jean-Marie Ramel Philippe Reynaud Valérie Olivier Françoise Poliakoff 《Plant pathology》2020,69(9):1798-1811
In Europe, the meadow spittlebug Philaenus spumarius is the main known vector of the quarantine bacterium Xylella fastidiosa. So far detection and identification of X. fastidiosa has more often been performed from plant matrices than insects, mainly using a real-time PCR and multilocus sequence typing (MLST) approach. Detection of X. fastidiosa in its insect vectors would enhance knowledge of the epidemiologic situation in France, specifically in the already infected Corsica and Provence-Alpes-Côte d’Azur (PACA) regions. The aim of this study was to validate a methodological approach to detect X. fastidiosa in P. spumarius, analysed individually or in groups of 10, using real-time PCR and MLST, and to apply the approach to more than 4,000 individuals collected between 2015 and 2019 from infected areas. The corresponding results expanded our knowledge of the epidemiology of X. fastidiosa in France: (a) X. fastidiosa subsp. multiplex including the sequence types ST6 and ST7 were identified in the insect vector; (b) the rate of positive insects per infected area was as high as 33.3% in Corsica or 50% in the PACA region; (c) positive adults were found during winter; and (d) the bacterial load in P. spumarius (droplet digital PCR) usually ranged from 103 to 104 cells per insect, but could be as high as 105 or 106 cells per insect for some individuals (13%). The subspecies and sequence types detected in P. spumarius corresponded to the situation officially reported for plants in the same areas. 相似文献
82.
Mark R. Liles Brian F. Manske Jean-Marie Rouillard Teri Balser Robert M. Goodman 《Soil biology & biochemistry》2010,42(5):739-747
We designed an oligonucleotide microarray using probe sequences based upon a phylogenetic analysis of 16S rRNA genes recovered from members of the bacterial division Acidobacteria. A total of 42,194 oligonucleotide probes targeting members of the Acidobacteria division at multiple phylogenetic levels were included on a high-density microarray. Positive control hybridizations revealed a linear relationship between hybridization signal and template concentration, and a substantial decrease in non-specific hybridization was achieved through the addition of 2.5 M betaine to the hybridization buffer. A mean hybridization signal value was calculated for each Acidobacteria lineage, with the resultant lineage-specific hybridization data revealing strong predictive value for the positive control hybridizations. The Acidobacteria phylochip was then used to evaluate Acidobacteria rRNA genes from a Wisconsin soil and within a soil clay fraction. The Acidobacteria hybridization profile revealed the predominance of Acidobacteria subdivisions four and six, and also suggested a decrease in the abundance of subdivision six relative to subdivision four in the soil clay fraction. The change in relative abundance of these subdivisions in a soil clay fraction was supported by data from quantitative PCR. These results support the utility of a phylogenetic microarray in revealing changes in microbial population-level distributions in a complex soil microbial assemblage. 相似文献
83.
Background
In spite of very low nutrient concentrations in its vicinity – both column and pore waters-, the Posidonia oceanica of the Revellata Bay displays high biomass and productivity. We measured the nutrient fluxes from the sediment into the water enclosed among the leaf shoots ("canopy water") to determine if it is possible source of nutrients for P. oceanica leaves. 相似文献84.
G W McLaughlin H E Bard R B Talbot 《Journal of the American Veterinary Medical Association》1976,168(4):319-321
A supply projection model to estimate the number of veterinarians available through the year 2020 was developed. When projected available manpower was compared with the need for veterinary medical services, as estimated in a National Academy of Science study, a net shortage was indicated in each year between 1976 and 2020. The manpower supply available if 3 additional veterinary colleges were developed in the United States was also estimated. It was concluded that, even with the additional output of these colleges, the supply of veterinarians will not keep pace with future needs for veterinary services. 相似文献
85.
The transition from aquatic to terrestrial locomotion was a key development in vertebrate evolution. We present a spinal cord model and its implementation in an amphibious salamander robot that demonstrates how a primitive neural circuit for swimming can be extended by phylogenetically more recent limb oscillatory centers to explain the ability of salamanders to switch between swimming and walking. The model suggests neural mechanisms for modulation of velocity, direction, and type of gait that are relevant for all tetrapods. It predicts that limb oscillatory centers have lower intrinsic frequencies than body oscillatory centers, and we present biological data supporting this. 相似文献
86.
87.
La Stéatose Hépatique et la Cholestérolémie Chez le Caneton Domestique au Cours d'une Malnutrition Protéique en Régime Orizé 下载免费PDF全文
The object of this experiment was to study the influence of essential amino acids on the growth, fatty infiltration of liver and cholesterol level of the serum in ducklings. 相似文献
88.
Tshilenge Georges Mbuyi Dundon William G. De Nardi Marco Mulumba Mfumu Leopold K. Rweyemamu Mark Kayembe-Ntumba Jean-Marie Masumu Justin 《Tropical animal health and production》2019,51(3):537-543
Tropical Animal Health and Production - This study aimed at assessing the serological and virological status of Rift Valley fever virus (RVFV) in cattle from four climatically diverse zones of the... 相似文献
89.
Frédéric Simard Diego Ayala Guy Colince Kamdem Marco Pombi Joachim Etouna Kenji Ose Jean-Marie Fotsing Didier Fontenille Nora J Besansky Carlo Costantini 《BMC ecology》2009,9(1):17-24
Background
Speciation among members of the Anopheles gambiae complex is thought to be promoted by disruptive selection and ecological divergence acting on sets of adaptation genes protected from recombination by polymorphic paracentric chromosomal inversions. However, shared chromosomal polymorphisms between the M and S molecular forms of An. gambiae and insufficient information about their relationship with ecological divergence challenge this view. We used Geographic Information Systems, Ecological Niche Factor Analysis, and Bayesian multilocus genetic clustering to explore the nature and extent of ecological and chromosomal differentiation of M and S across all the biogeographic domains of Cameroon in Central Africa, in order to understand the role of chromosomal arrangements in ecological specialisation within and among molecular forms. 相似文献90.
Carlo Costantini Diego Ayala Wamdaogo M Guelbeogo Marco Pombi Corentin Y Some Imael HN Bassole Kenji Ose Jean-Marie Fotsing N'Falé Sagnon Didier Fontenille Nora J Besansky Frédéric Simard 《BMC ecology》2009,9(1):1-27