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131.
Moreira RF Trugo LC Pietroluongo M De Maria CA 《Journal of agricultural and food chemistry》2002,50(26):7616-7621
The aim of this work was to characterize the volatile fractions of two Brazilian honeys known as caju and marmeleiro. The volatile components were isolated by a column extraction technique using acetone as the extraction solvent. Totals of 59 and 36 volatile compounds were definitely or tentatively identified in the caju and marmeleiro honeys, respectively, using reference substances, mass spectral libraries, and the odor qualities of the compounds eluted from the GC column. Aroma extraction dilution analysis allowed the tentative identification of furfuryl mercaptan, benzyl alcohol, delta-octalactone, gamma-decalactone, eugenol, benzoic acid, isovaleric acid, phenylethyl alcohol, and 2-methoxyphenol as impact volatile compounds in the caju honey. In the marmeleiro honey, only isovaleric acid, gamma-decalactone, benzoic acid, and vanillin were considered to be potent odorants. This study showed that the medium- to high-boiling volatile compounds are important contributors to the characteristic aroma of these honeys. 相似文献
132.
133.
The present investigation was intended to show a different immunohistochemical profile of matrix metalloproteinase-2 and Tissue
inhibitor metalloproteinase-2 in bovine uteri with adenomyosis during follicular phase. Uterine samples of 32 cows in reproductive
age were taken from the medial third of one of the uterine horns and grouped according to the adenomyosis degree (superficial
and deep). Tissue sections (4 μm) were incubated overnight at 4°C with monoclonal antibody for matrix metalloproteinase-2
and Tissue inhibitor metalloproteinase-2. Staining intensities were evaluated in the luminal epithelium, ectopic and dystopic
endometrial tissue (stroma, capillaries and glands), endometrial-myometrial border, myometrium, myometrial vessels (middle
tunic and endothelium). The matrix metalloproteinase-2 expression was higher for deep adenomyosis samples, showing a differential
mean reactivity in superficial endometrium, myometrial vessels, myometrium adjacent to adenomyotic focus and endometrial-myometrial
border (P < 0.05). Moreover, matrix metalloproteinase-2 expression was higher in deep adenomyosis samples than that of Tissue inhibitor
metalloproteinase-2 in almost all uterine structures analyzed (except for the endometrial and myometrial vessels and endometrial-myometrial
border). The opposite was observed in the follicular phase, for both normal specimens and with superficial adenomyosis, where
Tissue inhibitor metalloproteinase-2 expression was higher than that of matrix metalloproteinase-2. In conclusion, a differential
pattern of matrix metalloproteinase-2 and Tissue inhibitor metalloproteinase-2 was observed in cow uteri with adenomyosis. 相似文献
134.
To confirm the taxonomic identification of a trypanosomatid found in the hindgut, rectum and Malpighian tubules of dog fleas captured in Belo Horizonte, Minas Gerais, Brazil, between April and November of 2005, 910 specimens of Ctenocephalides felis felis were removed from street dogs and dissected, and isolates from their digestive tracts were cultivated in NNN-alpha-MEM medium. Four different morphological forms were observed in culture: long, slender, twisted promastigotes with a long flagellum; short, stubby, non-twisted promastigotes; rounded amastigotes; and cyst-like bodies. Twisted and non-twisted promastigotes were frequently seen forming rosettes, and these two forms presented significant differences (P<0.01) in terms of their morphological characteristics. Unlike the promastigote forms observed throughout the culture period, rounded amastigotes were seen only in the lag phase, and the cyst-like bodies were only seen in the decline phase. The trypanosomatid DNA obtained from the culture was analyzed by the polymerase chain reaction (PCR) method and found to be negative for Leishmania infantum chagasi. Based on the growth pattern, morphological parameters and molecular analysis, the flagellates were confirmed to be Leptomonas ctenocephali. The significance of this infection for animals is also commented. 相似文献
135.
Luppi MM Luiz AP Coelho FM Malta Mde C Preis IS Ecco R da Fonseca FG Resende M 《Veterinary microbiology》2011,154(1-2):69-77
Psittacid herpesvirus (PsHV) was isolated from 41 birds kept in captivity in Belo Horizonte, Minas Gerais/Brazil using chicken embryo fibroblasts (CEF) cell cultures. For this study, leukocytes or cloacal swabs of live birds were used. Also, portions of liver, spleen or kidney from birds collected at necropsy were utilized for these tests. PCR tests confirmed the presence of PsHV in 100% of samples. Thirty-three of the PCR products were sequenced and the results disclosed a 99% and 100% identity when compared with other sequences PsHV-1 (AY372243.1 and AF261756.1), previously deposited in GenBank. In addition, histopathology was performed and 19 of the 29 birds contained random multifocal lymphoplasmacytic hepatitis with necrotic foci, suggestive of viral infection. Three samples were examined by electron microscopy to visualize the viral particles obtained from cell culture. The viral structures measured 269 nm in average, had envelopes with an icosahedral capsid and tegument, consistent with herpesvirus. Thus, a total of 41 isolates were obtained from PsHV cell cultivation in CEF, confirming the circulation of the virus between parrots kept in captivity in Belo Horizonte, and affirming the importance of further studies in this area. 相似文献
136.
A national serological survey to verify Australia's freedom from porcine reproductive and respiratory syndrome 总被引:4,自引:0,他引:4
MG GARNER LJ GLEESON PK HOLYOAKE RM CANNON WJ DOUGHTY 《Australian veterinary journal》1997,75(8):596-600
Objective To provide serological data to support Australia's claim of freedom from porcine reproductive and respiratory syndrome.
Design A national serological survey was designed to provide 99% confidence of detecting at least one infected pig herd in Australia, assuming that at least 5% of herds would have been exposed to porcine reproductive and respiratory syndrome virus and that at least 25% of the 'finisher' pigs in these herds would have antibodies to the virus.
Procedure A two-stage testing regime was used. All samples were tested with a commercially available enzyme-linked immunosorbent assay. If assay reactions were found, all samples from the herd were to be tested using the indirect immunofluorescence antibody assay.
Results Of the 875 samples from 163 herds from all States in Australia, there was some evidence of reactivity in only four samples from four herds on the enzyme-linked immunosorbent assay. Further testing using the indirect immunofluorescence antibody assay according to the study protocol demonstrated that the reactions were not due to the presence of specific porcine reproductive and respiratory syndrome virus antibodies in the sera.
Conclusion The results of this study support the view that Australian pigs are free of porcine reproductive and respiratory syndrome virus. 相似文献
Design A national serological survey was designed to provide 99% confidence of detecting at least one infected pig herd in Australia, assuming that at least 5% of herds would have been exposed to porcine reproductive and respiratory syndrome virus and that at least 25% of the 'finisher' pigs in these herds would have antibodies to the virus.
Procedure A two-stage testing regime was used. All samples were tested with a commercially available enzyme-linked immunosorbent assay. If assay reactions were found, all samples from the herd were to be tested using the indirect immunofluorescence antibody assay.
Results Of the 875 samples from 163 herds from all States in Australia, there was some evidence of reactivity in only four samples from four herds on the enzyme-linked immunosorbent assay. Further testing using the indirect immunofluorescence antibody assay according to the study protocol demonstrated that the reactions were not due to the presence of specific porcine reproductive and respiratory syndrome virus antibodies in the sera.
Conclusion The results of this study support the view that Australian pigs are free of porcine reproductive and respiratory syndrome virus. 相似文献
137.
138.
In this paper we test the hypothesis that landscape changes in a region of Northern Portugal (Minho) in the last 40 years could be predicted from socioeconomic and political history. The major predicted changes were related to agricultural abandonment and afforestation. We further predicted that these changes contributed to increased fire risk. Analysis of aerial photography for the years 1958, 1968, 1983 and 1995 in a study area of 3700 ha revealed a significant decline in agricultural areas and low shrublands and an increase in tall shrublands and forests. This represented a 20–40% increase in fuel accumulation at a landscape level, suggesting that the abandonment of farming activities is a major driving force of increasing fire occurrence in the region. With one exception, all the predictions were partly or totally confirmed. This study confirms that socioeconomic factors might explain a significant part of the variation in landscape composition across time, in the Mediterranean region. 相似文献
139.
A. M. Orsi S. Mello Dias J. E. Moreira J. A. Camilli 《Anatomia, histologia, embryologia》1987,16(2):97-102
The morphological development of the seminiferous epithelium in the pig at different ages ( Sus scrofa , Landrace breed)
In the Pig, Landrace breed, were observed, at different ages, among 15 to 210–220 days, the morphological patterns of the seminiferous epithelium that lines "cordonal" tubules at 15 to 30 days of postnatal and "luminal" tubules at 120 to 210–220 days of age. Although some morphological events of cellular differentiation were observed at 120 days, and the spermatogenesis process apparently could be observed at 180–190 days, really the overall characteristics of the cellular differentiation in the seminiferous epithelium, with the presence of luminal spermatozoa, were observed at 210–220 days of age. This last stage is considered as the puberal age. 相似文献
In the Pig, Landrace breed, were observed, at different ages, among 15 to 210–220 days, the morphological patterns of the seminiferous epithelium that lines "cordonal" tubules at 15 to 30 days of postnatal and "luminal" tubules at 120 to 210–220 days of age. Although some morphological events of cellular differentiation were observed at 120 days, and the spermatogenesis process apparently could be observed at 180–190 days, really the overall characteristics of the cellular differentiation in the seminiferous epithelium, with the presence of luminal spermatozoa, were observed at 210–220 days of age. This last stage is considered as the puberal age. 相似文献
140.
Souza MR Moreira JL Barbosa FH Cerqueira MM Nunes AC Nicoli JR 《Veterinary microbiology》2007,120(1-2):142-150
In the present study, lactic acid bacteria (LAB) from the cecum of chickens bred either under intensive (commercial broilers) or extensive (free-range) conditions were isolated, identified and some of their probiotic characteristics determined. The LAB identified by 16S-23S rRNA PCR-ARDRA were mainly of Lactobacillus species and to a lesser extent of Enterococcus spp. for all animals. Free-range chickens showed a higher presence of Lactobacillus acidophilus while Lactobacillus reuteri and Lactobacillus johnsonii were more frequently recovered from commercial broilers. Lactobacillus crispatus was found only in commercial broilers, Lactobacillus vaginalis and Lactobacillus agilis only in free-range chickens and Lactobacillus salivarius in both types. Enterococcus isolates from ceca of commercial broilers showed a higher resistance to antimicrobial drugs. Lactobacillus isolates from free-range chickens presented a higher frequency of in vitro antagonistic activity against selected pathogens than from commercial broilers. All LAB isolates had predominantly non-hydrophobic surfaces, but with variations depending on age of the chickens and breeding conditions. Animal breeding caused variation on composition, antimicrobial susceptibility, antagonistic activity and surface hydrophobicity of LAB from chicken cecum. LAB isolates from ceca of free-range chickens have potential as probiotic agents, which may be used in the future as replacing the use of antimicrobials as growth promoters. 相似文献