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211.
Soil salinity and sodicity are land degradation processes that strongly alter soil quality and consequently plant productivity. The reclamation of soils affected by salinity and/or sodicity is an important goal to maintain the sustainability of production. The objectives of this review were (1) to investigate the effectiveness of different organic amendments to reclaim saline/sodic soils and improve environmental quality and productivity of agro-ecosystems and (2) to provide useful information on the most appropriate waste management for minimizing any potential risks. To achieve these aims, recently published literature, related to field and laboratory studies, considering the effects of a wide range of organic amendments on main soil properties, was collected. Results of these studies underline that input of exogenous organic matter (manure, plant residues, by-product of farming or municipal activities, etc.) can be a feasible way to reclaim soils with serious problems of salinity and sodicity. Optimal rates (not greater than 50 t ha?1) of different organic amendments can improve physical (soil structure, permeability, water holding capacity, etc.) and chemical (pH, cation exchangeable capacity, etc.) soil properties, favoring plant growth and microbial activity, without any risks for the environment (subsoil and groundwater contamination). Of course, it is very important to characterize carefully the organic wastes before their use in agriculture and optimize their management, for avoiding further land degradation. 相似文献
212.
Fábio Raphael Pascoti Bruhn Guilherme Loureiro Werneck David Soeiro Barbosa Daniel Cardoso Portela Câmara Taynãna César Simões Lia Puppim Buzanovsky Anna Gabryela Sousa Duarte Saulo Nascimento de Melo Diogo Tavares Cardoso Lucas Edel Donato Ana Nilce Silveira Maia-Elkhoury Vinícius Silva Belo 《Zoonoses and public health》2024,71(2):144-156
213.
214.
Prevalence and genetic characterization of Hepatitis E virus in paired samples of feces and serum from naturally infected pigs 下载免费PDF全文
Salceda Fernndez-Barredo Carolina Galiana Angel García Maria Teresa Gmez-Muoz Santiago Vega Manuel A. Rodríguez-Iglesias Maria Teresa Prez-Gracia 《Canadian journal of veterinary research》2007,71(3):236-240
This study describes the distribution of Hepatitis E virus (HEV) in a naturally infected swine population and the genetic relatedness of HEV strains on swine farms in Spain. Of fecal and serum samples collected from 131 pigs and manure-ditch samples collected from 17 farms, HEV was detected in 16%, 14%, and 59%, respectively, for an overall prevalence rate of 23%. The maximum prevalence rates for feces and serum were in pigs 5 to 12 wk old. A high prevalence of the virus in feces (18%) was observed in sows. Gene sequencing was performed on 6 strains from feces, serum, and manure ditch: the nucleotide identities varied from 81.5% to 99% when compared with those of other strains of genotype 3 isolated from swine. This is the first study in Europe to show the variation in virus distribution by age in feces and serum in a naturally infected swine population. 相似文献
215.
Wilson Roberto Maluf Vanisse de Fátima Silva Maria das Graças Cardoso Luiz Antonio Augusto Gomes Álvaro Carlos Gonçalves Neto Gabriel Mascarenhas Maciel Daniela Aparecida Castro Nízio 《Euphytica》2010,176(1):113-123
Zingiberene (ZGB) and acylsugars (AS) are allelochemicals responsible for high levels of arthropod resistance found in Solanum habrochaites (= Lycopersicon hirsutum) var. hirsutum ‘PI 127826’ and S. (= L.) pennelli ‘LA 716’, respectively. These accessions were used to develop commercial lines with good levels of pest resistance. The objective
of the present work was to assess the ZGB and AS contents and the levels of resistance to Tuta absoluta in tomato hybrids between high ZGB × high AS lines, as compared with their parental lines and with commercial checks. High
AS homozygous lines [TOM-688 and TOM-689, both originated from the interspecific cross S. lycopersicum (= L. esculentum) × S. pennelli], high ZGB homozygous lines (ZGB-703 and ZGB-704, both derived from the interspecific cross S. lycopersicum × S. habrochaites var. hirsutum), double heterozygotes for both ZGB and AS, single heterozygotes for ZGB, and single heterozygotes for AS were assessed for
AS and ZGB contents. Low-ZGB low-AS checks ‘Débora Max’ and ‘TOM-684’ were used, as well as checks with high ZGB (PI 127826)
and high AS (LA 716). The genotypes were submitted to infestation with South American tomato pinworm adults in a screenhouse,
and oviposition counts were taken 10 days after the initial infestation date. Plants were scored for overall plant damage
and percent leaflets attacked up to the 38th day after infestation. Genotypes heterozygous for ZGB or AS showed allelochemical
contents intermediate to those of their high and low content parents, indicating incompletely dominant gene action for contents
of each of the allelochemicals. There were no significant differences in T. absoluta oviposition between high-AS homozygous genotypes, high-ZGB homozygotes, single heterozygotes for AS, single heterozygotes
for ZGB and double heterozygotes for ZGB and AS, but all these genotypes showed egg counts significantly lower than the low-ZGB
low-AS checks. Feeding damage of T. absoluta was higher in the low-ZGB low-AS checks than in any other ZGB-rich or AS-rich tomato genotype. Relative to ZGB or AS single
heterozygotes, the heterozygotes for both ZGB and AS showed higher levels of resistance to the insect, as measured by overall
plant damage, indicating a synergic effect of the allelochemicals on resistance. 相似文献
216.
Gómez C Pinal L Franco J Carrillo JM Ramírez J 《Veterinary immunology and immunopathology》2007,117(3-4):249-253
A total of 41 isolates of Staphylococcus aureus obtained from bovine mastitis in 7 different states in Mexico were analyzed by the polymerase chain reaction (PCR) to determine the presence of encoding genes for enterotoxins A, B and C. The oligonucleotides were designed by specific regions of the sea, seb, sec genes. Surprisingly, none of the isolates presented the prospective amplification bands when they were run on agarose gels. On the contrary, reference strains CECT 976 SEA; CECT 5191 SEB; and CECT 4465 SEC showed the prospective amplification products. In order to confirm these results, enterotoxin production A, B, C, D, and E was determined by enzyme linked fluorescent assay (ELFA) using a MiniVIDAS system, on 15 Staphylococcus aureus selected at random from among the 41 isolates. None of the analyzed strains was positive to the test, whereas reference strains enterotoxins producing: CECT 976 SEA; CECT 5191 SEB; CECT 4465 SEC, CECT 4466 SED; CECT 5192 SEE produced concentrations of the toxins detected for this technique. The role of enterotoxins in the pathogenicity of S. aureus in bovine mastitis in Mexico is discussed. 相似文献
217.
Lilenbaum W Monteiro RV Ristow P Fraguas S Cardoso VS Fedullo LP 《Research in veterinary science》2002,73(3):319-321
Serum samples from 77 animals belonging to 38 species and 19 families in Rio de Janeiro Zoo, Brazil were tested for antibodies against serovars of Leptospira interrogans by microscopic agglutination test. Antibodies were detected in serum samples of 37.7% of all animals belonging to 10 families. Seropositivity was more common in the Carnivora Canidae (7/9), Procyonidae (5/9) and the Edentata Myrmecophagidae (5/9). Icterohaemorrhagiae was the most common serogroup. Seropositivity was less common in primates. 相似文献
218.
David Johnson Christopher Barrio Frojn Nicholas Bax Piers Dunstan Skipton Woolley Pat Halpin Daniel Dunn Carolina Hazin Maria Dias Tammy Davies Jorge Jimnez Erick Ross Cindy Van Dover Giuseppe Notarbartolo Di Sciara Erich Hoyt Michael J. Tetley Vikki Gunn Henning Von Nordheim 《水产资源保护:海洋与淡水生态系统》2019,29(Z2):162-169
219.
Julian R. Mateus-Rodriguez Stef de Haan Jorge L. Andrade-Piedra Luis Maldonado Guy Hareau Ian Barker Carlos Chuquillanqui Victor Otazú Rebeca Frisancho Carolina Bastos Arione S. Pereira Carlos A. Medeiros Fabian Montesdeoca Jacqueline Benítez 《American Journal of Potato Research》2013,90(4):357-368
Producing large quantities of high quality mini-tubers at low cost is essential for an economically viable supply of seed potatoes. Here we systematize the technical and economic aspects of aeroponics and provide a benchmark comparison of this technology with other mini-tuber production systems as developed in Latin America: conventional, semi-hydroponics, and fiber-cement tiles technology. Research methodologies included: 3-year registration of cash flows and production registers of aeroponics, economic and technical surveys, in-depth inquiry with managers of technologies. Results show that aeroponics as promoted by the International Potato Center (CIP) has several advantages, including high multiplication rates (up to 1:45), high production efficiency per area (> 900 mini-tubers per m2), savings in water, chemicals and/or energy, and positive economic indicators. The fiber-cement tiles technology from Brazil is also shown to be highly efficient and slightly more robust compared to aeroponics. Preconditions for the successful adoption of the different technologies in developing countries are discussed. 相似文献