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991.
Adjuvant effect of green propolis on humoral immune response of bovines immunized with bovine herpesvirus type 5 总被引:1,自引:0,他引:1
Fischer G Cleff MB Dummer LA Paulino N Paulino AS de Oliveira Vilela C Campos FS Storch T D'Avila Vargas G de Oliveira Hübner S Vidor T 《Veterinary immunology and immunopathology》2007,116(1-2):79-84
Despite recent technological advances in vaccine production, most vaccines depend on the association with adjuvant substances. In this study, propolis, which has been attracting the attention of researchers due to its bioactive properties, was evaluated as an immunological adjuvant. The association of 40mg/dose of an ethanolic extract of green propolis with an inactivated oil vaccine against bovine herpesvirus type 5 (BoHV-5), resulted in a significant increase (P<0.01) in the neutralizing antibody levels, comparing to the bovines that received the same vaccine without propolis. Besides, propolis increased the percentage of animals with high antibody titers (above 32). Phenolic compounds such as artepillin C (3,5-diprenyl-4-hydroxycinnamic acid) and the derivatives of cinnamic acid besides other flavonoid substances were abundant in the propolis extract used, and they could be the main substances with adjuvant action. The effect of the green propolis extract on the humoral immune response can be exploited in the development of new vaccines. 相似文献
992.
Gimenez G Florin-Christensen M Belaunzarán ML Isola EL Suárez CE Florin-Christensen J 《Veterinary immunology and immunopathology》2007,119(3-4):171-179
Erythrocytes of bovines and other ruminants have a strikingly anomalous phospholipid composition, with low or absent phosphatidylcholine (PC) together with high sphingomyelin (SM) content. Here, we report the presence in normal bovine serum of high levels of anti-phospholipid antibodies of IgM isotype against, PC and the phosphono analogue of phosphatidylethanolamine, aminoethylphosphonolipid (AEPL), normally produced by rumen ciliates. In contrast, no antibodies were detected against SM or N-acyl-phosphatidylethanolamine (NAPE), the major components of bovine erythrocytes. In addition, we found that exposure of the ciliate Tetrahymena thermophila to bovine serum results in rapid lysis, an effect that was inhibited by adsorption of the serum with SM/AEPL liposomes. Furthermore, incubation with bovine serum had a similar effect on freshly obtained ruminal ciliates, and the lytic activity was eliminated by pre-adsorption of the serum with SM/PE liposomes. The ruminant mode of life with its concomitant ciliate fauna is hereby linked to the peculiar conformation of bovine erythrocyte membranes. We propose that the unique phospholipid composition of bovine erythrocytes appears as an evolutionary adaptation to tolerate the lytic effects of anti-phospholipid antibodies generated against AEPL, a membrane component of the huge mass of ruminal ciliates, necessary commensals of this group of mammals. 相似文献
993.
Simón F Kramer LH Román A Blasini W Morchón R Marcos-Atxutegi C Grandi G Genchi C 《Veterinary research communications》2007,31(2):161-171
Heartworm disease caused by Dirofilaria immitis affects canine and feline hosts, with infections occasionally being reported in humans. Studies have shown that both dirofilarial
antigens and those derived from its bacterial endosymbiont Wolbachia, interact with the host organism during canine, feline and human infections and participate in the development of the pathology
and in the regulation of the host’s immune response. Both innate and acquired immune responses are observed and the development
of the acquired response may depend on the host and, or on its parasitological status. This review aims at illustrating current
research on the role of both D. immitis and Wolbachia, in the immunology and immunopathology of dirofilariosis. 相似文献
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997.
Application of RAPD markers in the characterisation of Chrysanthemum varieties and the assessment of somaclonal variation 总被引:1,自引:0,他引:1
Characterisation of fifteen commercial varieties of Chrysanthemum was carried out through RAPD analysis. Varieties could be distinguished from each other and the level of similarity between
varieties seemed to be not very high. In vitro cultures were establish from four varieties and were subjected to different proliferation conditions. Five individuals from
each variety and treatment were analysed using RAPD at the beginning of the treatment and after a month of culture. Variation
was detected at both stages of the culture period. The rate of variation found showed differences between varieties, but no
significant difference was found between culture conditions.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
998.
Barbarita Companioni Mayda Arzola Yania Rodríguez Marais Mosqueda María Cristina Pérez Orlando Borrás José Carlos Lorenzo Ramón Santos 《Euphytica》2003,130(3):341-347
Banana and plantain are among the most important food crops in developing countries but production is threatened by increasing
virulent forms of Fusarium oxysporum f. sp. cubense. Chemical control is not economically effective and,therefore, breeding programs are necessary. Traditional field studies
of new genotype resistance to this disease are time-consuming and destructive. Therefore,we developed a rapid and non-destructive
procedure to differentiate field-grown banana resistant from susceptible clones. This procedure implicates application of
culture filtrates of Fusarium oxysporum f. sp. cubense race 1 onto banana leaves. The relationship between duration of the fungal in vitro incubation, and the fungal culture fresh mass, the culture filtrate absorbency, and the Gross Michel (susceptible cultivar)leaf
lesion area (after application of the culture filtrate) were similar and at 24day-incubation the highest values of the recorded
indicators were observed. A comparison between Gross Michel and FHIA-01(resistant) was also performed. The most relevant differences
between cultivars were observed at 48 hours after application of the culture filtrate, and in the middle-aged leaves. The
position of the culture filtrate application in the leaf limb (distal, middle, proximal) was not determinant. A wider comparison
among banana cultivars confirmed previous results informed by other researchers using different systems to study this plant-fungus
interaction. Such a confirmation validates the effectiveness of the procedure described here to select rapid and non-destructively
banana resistance to this disease at field level.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
999.
Accumulation of soluble phenolic compounds in sunflower capitula correlates with resistance to Sclerotinia sclerotiorum 总被引:2,自引:0,他引:2
Disease symptoms and total soluble phenolics content have been analysed in four sunflower (Helianthus annuus L.)lines with different resistance levels(from highly susceptible to resistant) to head rot caused by Sclerotinia sclerotiorum (Lib.) de Bary. At the beginning of the flowering stage, capitula were inoculated by spraying with a water suspension of
ascospores, and disease symptoms were evaluated from day 6 to day14 after inoculation. The most susceptible genotypes showed
all their ovaries to be necrosed and abundant lesions in corollas, bracts and receptacle. In the resistant line, the ovary
and corolla were only partially necrosed with no symptoms in the bracts or the receptacle. Total soluble phenolics were extracted
and quantified from different parts of the capitulum in both inoculated and non-inoculated plants. The amount of phenolic
compounds depended on the sunflower line, the time after inoculation, and the tissue. Higher constitutive and induced phenolic
content as well as phenylalanine ammonia-lyase activity were present in the most resistant line, these differences correlated
with the absence/presence of disease symptoms.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
1000.
A 2-year study of autumn-sown white lupin (Lupinus albus L.) was conducted under rainfed Mediterranean conditions in southern Spain. 108 landraces were evaluated for yield and major
phonological and plant structural characteristics. Path coefficient and Genotype-Trait (GT) biplot analysis were used. Applying
both types of analyses to the multiple trait data revealed that GT biplot graphically displayed the interrelationships among
traits and facilitated visual comparison of accessions and selection. Wide variation was observed for trait phenology (dates
of flowering and maturity), plant structure (plant and first order inflorescence height) and yield characters (first order
branches, first order inflorescence and total yield). It was found that the accessions with the highest yields were the tallest
and the latest to flower, both on the mainstem and on the lowest first order branch, and also were the latest to mature. GT
biplots also had suggested as the accessions have been displayed according to their origins. The results showed that foreign
germplasm may be an important material for improving some yield components such as number of pods and seeds per plant of locally
adapted lupins in Spain.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献