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21.
用10年生丛生竹的节片通过离体腋笋增殖和生根产生出府竹小苗。不同季节对无菌培养物的建立、腋芽发萌和初代培养的影响很大。3片丛生林中,无菌培养物的建立有差别,但腋芽发萌没有差别。用加有31.06uM BA和2.85um IAA的MS液体介质,最大的增值率为3.18;用加有20~25um IBA MS液体介质,离体生根率为66.7~77.8%。用不同的植物生长素,生根所用的天数也不同,而IBA液能在短期促进生根,仅仅为2-3周。成功炼苗后,在装有土壤、沙子和农家肥塑料袋里,离体繁殖的小苗成活率为90%,大约有2000株小苗用于野外栽植。 相似文献
22.
Host differentiation and variability of Orobanche crenata populations from legume species in Morocco as revealed by cross‐infestation and molecular analysis
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23.
Neil A. Bryant Adam S. Rash Alana L. Woodward Elizabeth Medcalf Maud Helwegen Franziska Wohlfender Fatima Cruz Claudia Herrmann Kerstin Borchers Ashish Tiwari Thomas M. Chambers J. Richard Newton Jennifer A. Mumford Debra M. Elton 《Veterinary microbiology》2011,147(1-2):19-27
Like other influenza A viruses, equine influenza virus undergoes antigenic drift. It is therefore essential that surveillance is carried out to ensure that recommended strains for inclusion in vaccines are kept up to date. Here we report antigenic and genetic characterisation carried out on equine influenza virus strains isolated in North America and Europe over a 2-year period from 2008 to 2009. Nasopharyngeal swabs were taken from equines showing acute clinical signs and submitted to diagnostic laboratories for testing and virus isolation in eggs. The sequence of the HA1 portion of the viral haemagglutinin was determined for each strain. Where possible, sequence was determined directly from swab material as well as from virus isolated in eggs. In Europe, 20 viruses were isolated from 15 sporadic outbreaks and 5 viruses were isolated from North America. All of the European and North American viruses were characterised as members of the Florida sublineage, with similarity to A/eq/Lincolnshire/1/07 (clade 1) or A/eq/Richmond/1/07 (clade 2). Antigenic characterisation by haemagglutination inhibition assay indicated that the two clades could be readily distinguished and there were also at least seven amino acid differences between them. The selection of vaccine strains for 2010 by the expert surveillance panel have taken these differences into account and it is now recommended that representatives of both Florida clade 1 and clade 2 are included in vaccines. 相似文献
24.
Francesco Carimi Francesco Mercati Roberto De Michele Maria Carola Fiore Paolo Riccardi Francesco Sunseri 《Genetic Resources and Crop Evolution》2011,58(7):967-975
The Sicilian grape cultivar ‘Nero d’Avola’ is among the oldest and most cultivated in the island, taking part in the production
of several red wines exported worldwide, including DOC wines (Etna Rosso and Cerasuolo di Vittoria). Due to the ancient origin
and repeated clonally propagation of the cultivar, phenotypic variability has been observed. Clone identification in this
important cultivar has so far relied on phenotypic and chemical traits analyses, often affected by environmental conditions.
Genetic markers, such as microsatellites, are particularly useful for cultivar identification, parentage testing, pedigree
reconstruction and population structure studies. In the present paper, microsatellites were used to analyze the intra-varietal
genetic diversity among 118 plants of ‘Nero d’Avola’, collected in 30 vineyards displaced in different areas of Sicily. Out
of 22 microsatellites, 11 showed polymorphism among samples and 15 different phylogenetic groups were identified. Results
show that ‘Nero d’Avola’ actually comprises different genetic profiles, although most of clones share a common origin. 相似文献
25.
Fatima Rukshana Clayton R. Butterly Jeff A. Baldock Caixian Tang 《Biology and Fertility of Soils》2011,47(1):51-62
The mechanisms by which organic materials affect soil pH are not fully understood. This study for the first time compared
the short-term effect of various model organic compounds on pH change of two soils differing in initial pH (Podosol of pH 4.4
and Tenosol of pH 6.1). Eight organic compounds, representing common compounds in plant residues, were selected based on the
number and type of chemical functional groups. The addition of organic acids (acetic, malic, citric, and benzoic acid) reduced
soil pH immediately due to H+ dissociation. The magnitude of pH decrease depended on the rate of application, degree of dissociation of the acids, and
initial soil pH. During a subsequent incubation, pH was slowly restored as these compounds were decomposed. The degree to
which pH was restored was reduced with increasing addition rate. The production of H+ ions was increased with increasing rate of acid addition and decreased over time. When potassium citrate (organic anion)
was added, soil pH increased due to H+ consumption upon decomposition. Compounds with amine groups (glucosamine hydrochloride) and less easily decomposable compounds
(phenol) did not significantly alter pH during 16-day shaking. Changes in pH after glucose addition were relatively small
compared with other compounds and were not expected because hydroxyl chemical groups of glucose are neutral. The present study
demonstrated that the addition of model organic compounds to soil caused soil pH to increase, decrease, or remains unaffected.
The extent and direction of pH change was dependent on the chemical functional group, addition rate, decomposition, and the
initial soil pH. 相似文献
26.
Sébastien Gogo Christophe Guimbaud Fatima Laggoun-Défarge Valéry Catoire Claude Robert 《Journal of Soils and Sediments》2011,11(4):545-551
Purpose
CH4 emissions from peatlands are space and time dependent. The variety of efflux routes contributes to these variabilities. CH4 bubbling remains difficult to investigate since it occurs on a timescale of seconds. The aims of this study were to use for the first time the recently built infrared high-resolution spectrometer, SPectrometre Infra-Rouge In situ Troposphérique to (1) measure in situ CH4 fluxes in natural and artificial peatland plot and (2) observe online bubbling events with quantification of CH4 emission fluxes corresponding to this very sudden degassing event. 相似文献27.
Castral TC Matos AP Monteiro JL Araujo FM Bondancia TM Batista-Pereira LG Fernandes JB Vieira PC da Silva MF Corrêa AG 《Journal of agricultural and food chemistry》2011,59(9):4822-4827
The fall armyworm Spodoptera frugiperda is a polyphagous pest that causes important damage in different regions of America and mainly affects corn crops in both tropical and subtropical areas. Currently, control relies on both transgenic plants and/or chemical pesticides. In this work we describe the preparation of an indexed combinatorial library of amides and its toxic effect by contact against S. frugiperda . (E)-1-(1-Piperidinyl)-3-[4-(trifluoromethoxy)phenyl]-2-propen-1-one was the most active compound with an LD(50) = 0.793 μg mg(-1) of larva. This amide was also evaluated by ingestion and at the lowest concentration (1 mg kg(-1)) achieved 83.3% mortality. 相似文献
28.
Rita Leogrande Ornella Lopedota Angelo Fiore Carolina Vitti Domenico Ventrella Francesco Montemurro 《Journal of plant nutrition》2013,36(13):1945-1962
The use of organic amendments in agriculture could sustain crop production and preserve the agroecosystem, due to their importance in the conservation of organic matter in soil. The objective of this research was to evaluate the effects of differing organic fertilizers and of previous crops on lettuce growth, nutritional status and yields. The effects on soil characteristics were further investigated. The research was carried out during two years (2006 and 2007) at Metaponto (MT) in southern Italy, on lettuce crops cultivated after eggplant and melon to avoid their continuous cropping. The effects of application of a mineral fertilizer (MF), and of three treatments with organic fertilizers (commercial stable manure - OM; anaerobic digestate based on wine distillery wastewater - AD; composted municipal solid organic wastes coming from the separate collection - MSW) were studied. Head average weight, leaf area index, nitrate content and SPAD readings during the cropping cycles did not show significant differences among fertilizer treatments. On the contrary, marketable yield and head average weight at the harvest presented significantly different among the three organic fertilizers. The average marketable yield and head average weight of organic fertilizers experimental (AD and MSW treatments) decreased of 16 and 17%, respectively, compared to OM treatment. The previous melon crop influenced positively all analyzed parameters of the lettuce compared with previous eggplant crop. The previous melon crop reached the highest marketable yield with an increase of 59% compared with previous eggplant crop. Compared to the mineral fertilizer, the organic ones significantly increased the extracted fraction of soil organic carbon (6.9, 10.7 and 14.9% for OM, AD and MSW, respectively), without significant changes for the humic and fulvic content. 相似文献
29.
Asma Ait Said Ahmed Oukabli Fatima Gaboun Marie Hélène Simard Cherkaoui El Modafar 《Genetic Resources and Crop Evolution》2013,60(3):927-938
In this paper, we report on morphological diversity, ecology and flowering phenological records of an endangered and an endemic species of Morocco Pyrus mamorensis Trab. For this study, a survey was undertaken in North-Western Morocco (Mamora forest and Zaër region) whereby 67 accessions of P. mamorensis were sampled. A set of 33 genotypes of Pyrus spp. from the international collection INRA-Angers (France) of the genus Pyrus were also analyzed. The variability of the total of 100 accessions was assessed by twenty-six characters including fourteen qualitative and twelve quantitative traits. The results demonstrated high levels of morphological variation in the sampled accessions of P. mamorensis and established the relationships among the local germplasm using the UPGMA cluster analysis and the factorial discriminant analysis. Furthermore, we were able to distinguish three types of flowering in the Mamora forest: early, intermediate and late flowering type. Otherwise, the UPGMA classification comparing local accessions of P. mamorensis to the international collection led to the formation of four major groups showing the closest correspondence to their geographical origins: (1) The North African species represented by P. mamorensis, (2) The East Asian pea species, (3) The West Asian species and (4) The European species. These findings suggest the importance of implementing a conservation strategy preserving the genetic resources of wild pear in North-Western Morocco. 相似文献
30.
Samira Gilanchi Banafshe Esmaeilzade Akram Eidi Mahmood Barati Soraya Mehrabi Fatima Moghani Ghoroghi Maliheh Nobakht 《Iranian Biomedical Journal》2014,18(3):136-142
Background: The seladin-1 (selective Alzheimer disease indicator-1), also known as DHCR24, is a gene found to be down-regulated in brain region affected by Alzheimer disease (AD). Whereas, hair follicle stem cells (HFSC), which are affected in with neurogenic potential, it might to hypothesize that this multipotent cell compartment is the predominant source of seladin-1. Our aim was to evaluate seladin-1 gene expression in hair follicle stem cells. Methods: In this study, bulge area of male Wistar rat HFSC were cultured and then characterized with Seladin-1 immunocytochemistry and flow cytometry on days 8 to 14. Next, 9-11-day cells were evaluated for seladin-1 gene expression by real-time PCR. Results: Our results indicated that expression of the seladin-1 gene (DHCR24) on days 9, 10, and 11 may contribute to the development of HFSC. However, the expression of this gene on day 11 was more than day 10 and on 10th day was more than day 9. Also, we assessed HFSC on day 14 and demonstrated these cells were positive for β-ш tubulin, and seladin-1 was not expressed in this day. Conclusion: HFSC express seladin-1 and this result demonstrates that these cells might be used to cell therapy for AD in future. Key Words: Seladin-1 (selective Alzheimer disease indicator-1), Alzheimer disease (AD), Hair follicle stem cells 相似文献