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811.
Ariadna Giné Cristina González Lydia Serrano Francisco Javier Sorribas 《European journal of plant pathology / European Foundation for Plant Pathology》2017,148(4):795-805
The influence of the squash hybrid RS841 rootstock (Cucurbita maxima x C. moschata) on population dynamics of Meloidogyne incognita and yield of cucumber cv. Dasher II was assessed during 2013 and 2014 in a plastic greenhouse. In addition, the relationship between ecophysiological parameters (plant water status, gas exchange, and leaf reflectance) and Pi and cucumber yield were also estimated in 2013. Nematode densities were determined at the beginning (Pi) and at the end (Pf) of each crop, and the relationship between these parameters was used to estimate the maximum multiplication rate (a), the maximum population density (M) and the equilibrium density (E) per grafted and ungrafted cucumber and cropping season. Moreover, the relationship between the multiplication rate (Pf/Pi) and Pi was compared between grafted and ungrafted cucumber per cropping season. Finally, the relative yield of grafted or ungrafted cucumber was plotted against Pi to determine the tolerance limit (T) and the minimum relative yield (m) by the Seinhorst damage function model. Values of a, M and E in grafted cucumber were higher than in ungrafted one irrespective of the cropping season. These results were supported by comparing the relationship between Pf/Pi and Pi between grafted and ungrafted cucumber. The relationship between Pi and yield fitted the Seinhorst damage function. The values of T and m did not differ between grafted and ungrafted each year. Predawn water potential, net photosynthetic rate, and leaf chlorophyll index decreased with increasing Pi. In addition, relative yield was related to variation in net photosynthetic rate and the leaf chlorophyll index. Under the conditions of this study, RS841 rootstock was neither resistant nor tolerant to M. incognita. 相似文献
812.
813.
814.
Javier Pérez‐Robles Ana Denisse Re Ivone Giffard‐Mena Fernando Díaz 《Aquaculture Research》2012,43(9):1372-1383
A physiological study was performed to explore the effects in Sphoeroides annulatus (Jenyns 1842) juveniles of exposure to different salinities 10, 17, 23, 29, 35 and 41‰ on oxygen consumption rate (OCR), ammonium excretion rate (AER), the oxygen‐nitrogen atomic ratio (O:N), osmoregulation and Na+/K+‐ATPase expression. The OCR values ranged from 27.9 to 30.9 mg O2 h?1 kg?1, displaying a Type 1 response pattern Kinne (1977). AER ranged from 0.60 to 0.69 mg h?1 kg?1, and O:N values were from 53.12 to 59.26, indicating that the puffers use proteins and lipids as an energy‐substrate. Osmoregulation in S. annulatus was hyposmotic in salinities of 23, 29, 35 and 41‰ and hyperosmotic in a salinity of 10‰. The isosmotic point of the bullseye puffer was 356 mmol kg?1 (10.5‰). The enzyme expression analysis indicates that the fish acclimated to 41‰ had the highest Na+/K+‐ATPase expression level, whereas, the lowest expression level was found close to the isosmotic point. Na+/K+‐ATPase expression in the gills was found to have a U‐shaped relationship with environmental salinity. We conclude that the bullseye puffer is strongly euryhaline and can be cultivated in a wide range of environments that has important economic implications. 相似文献
815.
Juan Estefanell Javier Roo Rafael Guirao Juan Manuel Afonso Hipólito Fernández‐Palacios Marisol Izquierdo Juan Socorro 《Aquaculture Research》2012,44(1):93-105
The aim of this study was to evaluate growth, biochemical composition and dietary nutrients utilization in Octopus vulgaris fed on four diets based on bogue Boops boops, from different origin and in two presentations: fresh discarded bogue (aquaculture by‐product) (DB‐f), fresh wild bogue (low price trash species) (WB‐f), discarded bogue agglutinated moist diet (DB‐m) and wild bogue agglutinated moist diet (WB‐m). Diets based on DB showed higher lipid content (19–26% dw) than those based on WB (5–6% dw). Octopuses fed on DB‐based diets showed higher growth (1.5–1.9% day?1) and higher protein efficiency ratio (0.64–0.69) than those fed on WB‐based diet (1.1–1.5% day?1 and 0.36–0.37 respectively), which suggests good utilization of dietary lipids and also a possible protein sparing effect by lipids in O. vulgaris. Octopuses fed on diets presented fresh showed a higher growth (1.9–1.5% day?1) and a higher feed efficiency (62–65%) than those fed on agglutinated diets (1.1–1.5% and 52–60% day?1 respectively). Regarding fatty acids, the digestive gland clearly reflected dietary lipid and fatty acid profile, while muscle showed a more stable composition. Low dietary ARA content reflected in octopus tissues, especially in specimens fed on DB‐based diets, which did not seem to affect growth during the experimental period. 相似文献
816.
Petra Ondrackova Katerina Nechvatalova Zdenka Kucerova Lenka Leva Javier Dominguez Martin Faldyna 《Veterinary research》2010,41(5)
Mononuclear phagocytes (MP) are cells of nonspecific immunity, playing an essential role in defense against bacterial pathogens. Although various MP subpopulations have been described in the pig, relations among these populations in vivo are unknown to date. The present study was aimed at describing porcine MP subpopulations infiltrating inflamed tissue of pigs under in vivo conditions. Actinobacillus pleuropneumoniae (APP) infection was used to induce an inflammatory response. CD172α, CD14, CD163, MHCII and CD203α cell surface molecules were used to identify MP by flow cytometry. Changes in MP subpopulations in the peripheral blood (PB) and bone marrow (BM) compartments along with the analysis of MP appearing in the inflamed lungs were assessed to elucidate the possible origin and maturation stages of the infiltrating MP. The MP population migrating to the inflamed lungs was phenotype CD14+ CD163+ CD203α+/− MHCII+/−. Concomitantly, after APP infection there was an increase in the PB MP CD14+ CD163+ CD203α− MHC II− population, suggesting that these cells give rise to inflammatory monocytes/macrophages. The CD203α and MHCII molecules appear on these cells after leaving the PB. In healthy animals, the BM MP precursors were represented by CD14− CD163− cells maturing directly into CD14+ CD163− that were then released into the PB. After infection, an altered maturation pathway of MP precursors appeared, represented by CD14− CD163− CD203α− MHCII− MP directly switching into CD14+ CD163+ CD203α− MHCII− MP. In conclusion, two different MP maturation pathways were suggested in pigs. The use of these pathways differs under inflammatory and noninflammatory conditions. 相似文献
817.
Maria Jesus Gracia Javier Lucientes Miguel Angel Peribáñez Juan Antonio Castillo Carlos Calvete Luis Miguel Ferrer 《Tropical animal health and production》2010,42(5):811-813
Slaughterhouse surveys to determine the prevalence and intensity of larval Oestrus ovis Linnaeus (Diptera: Oestridae) in sheep, were conducted monthly for 1 year in northeastern Spain. The prevalence of O. ovis in 120 sheep in northeast Spain was 84.2%. The monthly prevalence ranged from 62.5% in January to 100% in June and October.
Of the 3,831 larvae collected, 3,005 were first instar larvae (78.4%), 744 second instar larvae (19.4%), and 82 third instar
larvae (2.1%). The mean larval burden per infected sheep was 37.9, throughout the year although infection was higher in October.
The high number of first stage larvae in winter (especially October, November, and December) may be due to a period of slower
larval maturation. Third-stage larvae were always present but sometimes in very low numbers compared to the total. According
to the results, oestrosis appears to be a serious problem in the region. 相似文献
818.
Juan Carlos Martínez-González Francisco Javier García-Esquivel Gaspar Manuel Parra-Bracamonte Héctor Castillo-Juárez Eugenia Guadalupe Cienfuegos-Rivas 《Tropical animal health and production》2010,42(5):887-892
The aim of this study was to estimate genetic parameters for growth traits in Mexican Nellore cattle. A univariate animal
model was used to estimate (co)variance components and genetic parameters. The traits evaluated were birth weight (BW), weaning
weight (WW), and yearling weight (YW). Models used included the fixed effects of contemporary groups (herd, sex, year, and
season of birth) and age of dam (linear and quadratic) as a covariate. They also included the animal, dam, and residual as
random effects. Phenotypic means (SD) for BW, WW, and YW were 31.4 (1.6), 175 (32), and 333 (70) kg, respectively. Direct
heritability, maternal heritability, and the genetic correlation between additive direct and maternal effects were 0.59, 0.17,
and −0.90 for BW; 0.29, 0.17, and −0.90 for WW; and 0.24, 0.15, and −0.86 for YW, respectively. The results showed moderate
direct and maternal heritabilities for the studied traits. The genetic correlations between direct and maternal effects were
negative and high for all the traits indicating important tradeoffs between direct and maternal effects. There are significant
possibilities for genetic progress for the growth traits studied if they are included in a breeding program considering these
associations. 相似文献
819.
820.
Lack of growth of heat-shocked Staphylococcus aureus surviving cells in common media and enterotoxin release. 总被引:1,自引:0,他引:1
F Javier Hernández E Gómez-Lucía J A Orden J Goyache A Doménech G Suárez 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1992,39(1):65-68
The ratio of the different types of S. aureus surviving cells immediately after sub-lethal heat treatment (52 degrees C for 15 min) was studied. A high ratio of cells which are unable to form colonies even in a common medium such as TSA was observed. This fact has not been reported previously for common media through recovery after heat shock has been widely studied. After the treatment, staphylococcal protein A, but no enterotoxin, was seen to be released into the extracellular environment. 相似文献