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31.
Bergamot peel is an underutilized byproduct of the essential oil and juice-processing industry. As with other Citrus peels, it still contains exploitable components, such as pectins and flavonoids. Commercial glycoside hydrolases, specifically a combination of pectolytic and cellulolytic enzymes, solubilized a high percentage of the material (81.94%). The flavonoid profile of the peel consisted of characteristic Citrus species flavanone rutinosides and neohesperosides derived from naringenin, eriodictyol, and hesperetin. In addition, a number of minor flavanone and flavone glycosides, not found in orange and lemon peels, were identified. The majority of flavonoids were extracted in the two 70% v/v EtOH extractions. Processing this material clearly has economic potential leading to low environmental impact.  相似文献   
32.
Summary

A cDNA clone, designated pepl, that encodes a putative seed storage protein in pecan (Carya illinoinensis) was isolated and characterized. Northern blot analysis indicated that this gene is embryo-specific, and is temporally expressed during the reserve accumulation stage of pecan seed development. The nucleotide sequence covers the partial coding region (135 base pairs) with a 3’ non-coding region of 219 base pairs. The deduced amino acid sequence consists of 45 amino acids that bears close identity to seed storage proteins from other plants.  相似文献   
33.
The enzymatic hydrolysis of brewers' spent grain (BSG) has been investigated through treatment with commercial carbohydrases and proteases. Resultant residues were then chemically fractionated and delignified. Enzymatic treatments released 25-30% of the BSG mass and yielded precursors suitable for subsequent conversion to potentially value-added products. Controlled chemical fractionation selectively solubilized arabinoxylan but with no differences apparent due to prior enzyme treatment. The loss of non-polysaccharide components during alkali treatment suggests the presence of a high proportion of alkali-soluble lignin. Further delignification of the alkali-insoluble residues and further chemical fractionation released the remaining hemicellulose, to yield a residue which was >90% cellulose. Further knowledge of the properties and interaction between BSG polymers will facilitate an improved enzyme-assisted total deconstruction of BSG and hence the exploitation of its biomass.  相似文献   
34.
A demand model was developed to determine the factors that affect the demand for potato products in the United States. The following market components were analyzed: potato chips; dehydrated-foodservice; dehydrated-retail; fresh; frozen-foodservice; and frozen-retail. Equations were estimated for each of the six components via ordinary least squares. Factors found to affect demand were population, consumer price index, consumer income, consumer debt, retail potato product price, females in the labor force, percentage of households with microwave ovens, restaurant meal expenditures, price of substitute potato products, price of complement products, and advertising expenditures. The demand for all of the potato products was found to be inelastic, but fresh demand was the most inelastic.  相似文献   
35.
36.
As with other areas of the world, herbage production of cool‐season grasses in irrigated semi‐arid areas of the western USA at high elevation declines during summer. The use of warm‐season grasses during this period could be a possible way to ameliorate this decline in herbage production. The ability of twenty‐one grass cultivars, representing seven warm‐season grass species, to establish in the summer of 2005, as measured by stand frequency and herbage production, the potential for damage in winter under irrigated conditions in 2005–2006 and the stand frequency in 2006 at two sites in semi‐arid environments of the western USA was compared with that of a cultivar of each of six cool‐season grass species. Some warm‐season grass species, including switchgrass (Panicum virgatum), showed potential for use in this environment, based on their similar herbage production in 2005 and similar values of stand frequency in 2005 and 2006 to that of cool‐season grasses. All the cultivars of the warm‐season grass species suffered greater winter damage than did the cultivars of the cool‐season species. The higher winter damage to the species of warm‐season grasses did not correspond with a lower stand frequency in the second year.  相似文献   
37.
Epizootic hemorrhagic disease virus (EHDV) is an Orbivirus. While not previously considered as an important disease in cattle, several EHDV serotypes (EHDV-6 and 7) have recently been implicated in disease outbreaks. The involvement of sheep in the epidemiology of EHDV is still not understood. In this study we compared the prevalence of antibodies to EHDV and bluetongue virus (BTV) in sheep to their prevalence in cattle after an outbreak of EHDV that occurred in Israel during 2006. Sixty-six sheep and lambs scattered in seven herds were compared to 114 cows and calves scattered in 13 dairy cattle herds, matched to the sheep herds by location. While antibody prevalence to EHDV was high in cattle (35.2% within the outbreak zone) no evidence of exposure to EHDV was found in sheep (p<0.0001). Antibodies to BTV were apparent in both cattle and sheep though in the former it was significantly higher (63.2%, 16.7% respectively, p<0.0001), suggesting higher exposure of cattle to biting Culicoides midges. Taken together, these results imply that sheep have a negligible role in the epidemiology of EHDV.  相似文献   
38.
Severe persistent orf in young goats.   总被引:1,自引:0,他引:1  
Orf (contagious ecthyma) is a viral disease of small and wild ruminants, humans, and less frequently other species. In sheep and goats, the disease is characterized by the formation of vesiculo-proliferative lesions in the skin of lips and nostril. Here, a form of generalized orf in 16 goat kids from 2 different locations in west Texas is described. The disease was characterized by multifocal, severe, proliferative dermatitis that persisted from about 2 months of age until the goat kids were euthanized 3 months later. All affected goats were Boer or Boer crosses under 1 year of age. The mean immunoglobulin concentration in sera of affected goats was elevated compared with healthy control goats. Severe to moderate lymphadenomegaly of the nodes draining the areas of the skin affected with orf lesions was present in all 16 goat kids. Suppurative arthritis, chronic fibrinous pneumonia, and premature thymic involution were found in 3, 5, and 7 of the goat kids, respectively. The skin lesions of 3 goat kids were infested with larvae of the opportunistic black garbage fly (Ophira sp.). The orf virus was identified in skin lesions by isolation in Marbin-Darby ovine kidney cells, electron microscopy, and amplification of viral DNA by polymerase chain reaction. The orf virus was not detected in peripheral blood or lymph node mononuclear cells of any of the goats. Cross-neutralization experiments showed that an ovine orf virus antiserum raised in sheep was more effective in neutralizing a sheep orf virus isolate than a caprine orf virus isolate. The clinical and epidemiological characteristics of these orf cases may be the result of susceptibility factors within some individuals of the Boer breed of goats.  相似文献   
39.
In recent years, infectious bursal disease virus (IBDV) has become a serious economic problem as a result of the emergence of new and very virulent strains. Most of the antibodies produced against IBDV are for the structural proteins viral protein (VP) 2 (VP2) and VP3. The purpose of this study was to test the potential of recombinant VP3 to induce protective antibodies. The gene for VP3 was isolated from a virulent strain of the virus and cloned into prokaryotic (Escherichia coli) and eukaryotic (baculovirus) expression systems. The protein expressed by both systems was of the expected size (32 kD) and was detected by anti-IBDV antibodies. Following partial purification, the polypeptides were injected into intact birds and induced the production of high levels of anti-IBDV antibodies, as detected by immunoblot and enzyme-linked immunosorbent assay tests. These antibodies did not prevent changes in the bursa and mortality when birds were challenged with a virulent IBDV strain after vaccination with the recombinant VP3. The results show that VP3 polypeptide cannot be used as a subunit vaccine against IBDV and raise questions concerning the nature of the neutralizing epitope on this structural protein.  相似文献   
40.
Tropical Animal Health and Production - The objective of this study was to evaluate carcass characteristics, meat quality, and organ and viscera weight of forty male sheep, not castrated, initially...  相似文献   
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