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71.
Canine atopic-like dermatitis (ALD) is suspected to be associated with food allergies, particularly those mediated by lymphocytes. In this study, 54 cases were included as ALD dogs, based on the negative IgE test results. In the dogs, the percentage of activated cells in helper-T lymphocytes was measured by flow cytometry using cultured peripheral lymphocytes under food allergen stimulation. We observed that 49 of the 54 ALD dogs (90.7%) had positive lymphocyte reactions against one or more food allergens. The most common food allergen was soybean, showing positive results in 21 dogs (42.9%), while the allergen to cause the lowest number of reactions was catfish (only 5 dogs, 10.2%). These results may be useful in considering elimination diets for ALD dogs.  相似文献   
72.
alpha-klotho was identified as a gene associated with premature aging-like phenotypes characterized by short lifespan. In mice, we found the molecular association of alpha-Klotho (alpha-Kl) and Na+,K+-adenosine triphosphatase (Na+,K+-ATPase) and provide evidence for an increase of abundance of Na+,K+-ATPase at the plasma membrane. Low concentrations of extracellular free calcium ([Ca2+]e) rapidly induce regulated parathyroid hormone (PTH) secretion in an alpha-Kl- and Na+,K+-ATPase-dependent manner. The increased Na+ gradient created by Na+,K+-ATPase activity might drive the transepithelial transport of Ca2+ in cooperation with ion channels and transporters in the choroid plexus and the kidney. Our findings reveal fundamental roles of alpha-Kl in the regulation of calcium metabolism.  相似文献   
73.
Nature and mechanisms of oxygenases   总被引:6,自引:0,他引:6  
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74.
With the goal of preparing low-cost functional food, squid protein hydrolysate (SPH) was extracted from four squid species by protease treatment. Peptides are the major components (approximately 84-88%) of the SPH. The stabilization effects of 5% SPH (dried weight/wet weight) on the state of water and the denaturation of frozen lizard fish Saurida wanieso myofibrillar protein (Mf) were evaluated on the basis of desorption isotherm curves with respect to Ca2+-ATPase inactivation and the presence of unfrozen water, which was determined using differential scanning calorimetry during dehydration, and the effects were compared with those of sodium glutamate. The Mf with SPH was found to contain higher levels of monolayer and multilayer sorption water, resulting in decreased water activity and Ca2+-ATPase inactivation. The amount of unfrozen water in Mf with SPH increased significantly, suggesting that the peptides of SPH stabilized water molecules on the hydration sphere of Mf, which maintained the structural stability of Mf, and therefore suppressed dehydration-induced denaturation. The effect by SPH was less than that by sodium glutamate.  相似文献   
75.
Acid Dissolution of Olivines, Feldspars and Dunite   总被引:1,自引:0,他引:1  
We have treated feldspars (orthoclase, albite, anorthite), JF-1 (a mixture of orthoclase and albite), olivines (fayalite, forsterite) and JP-1 (dunite: an olivine-rich rock) with HNO3 solution at pH 2 for 10 – 1200 min. The resultant changes in surface composition were assessed by X-ray photoelectron spectroscopy (XPS). The XPS data for fayalite, notably shifts in the Si 2s and O 1s binding energies, indicate preferential dissolution of Fe and formation of a Si-rich surface layer composed of amorphous silica. A Si-rich layer also forms on the surface of the other minerals as the result of acid treatment but the changes in binding energies are relatively small. Forsterite and anorthite dissolved almost congruently in acid solutions, and the Si-rich surface layer is poorly developed. Unlike forsterite, JP-1 shows preferential leaching of Mg relative to Si. Although forsterite is the major constituent of JP-1, this rock also contains some talc and orthopyroxene. These minor mineral constituents appear to influence the behavior of JP-1 in acid solutions. On the other hand, the dissolution and resultant surface alteration of JF-1 were comparable to those of its constituent minerals. The extent of Si-rich surface layer formation followed the order of albite = orthoclase > anorthite for the feldspars, and fayalite > forsterite for the olivines.  相似文献   
76.
The present study was undertaken to examine whether the von Willebrand factor (vWF) expression in the follicular microvasculature in the cystic follicles differs from that in the atretic follicles. Paraffin sections of healthy, atretic and cystic follicles were immunostained with rabbit monoclonal antibody to vWF. The vWF-positive cells were counted in four different regions of a follicle from the apical to the basal side. In all types of follicles, immunoreactions for vWF were observed in the endothelial cells of capillaries as well as veins and arteries in the theca interna and externa. In the theca interna, vWF-positive areas were significantly lower in the Type A and B cystic follicles compared to advanced and late atretic follicles. In the theca externa, the vWF-positive blood vessels and vWF-positive area were significantly smaller in all types of cystic follicles than in the healthy or atretic follicles. From these results, it is suggested that in the cystic follicles the induction of vWF in the follicular microvasculature system is reduced, which may suppress the degeneration of vascular system. Continuation of stability in vasculature may be one of the factors that delays the tissue regression in the cystic follicles, and also contributes to the accumulation of follicular fluid that originates from the serum.  相似文献   
77.
78.
Common bean, Phaseolus vulgaris L. is intercropped or relay cropped with maize in many Andean highlands of Colombia and Peru. Breeding beans for the target multiple cropping systems is essential for the development of productive and sustainable agriculture for the Andean smallholders. Outline of the breeding programme should follow the farming system approach with the establishment of on-farm trials and early farmers involvement. Bean breeding is oriented to minimize intercrop competition and to stabilize complementarity with maize. Genetic traits needed for improved varieties are divided as follows : traits not interacting with the cropping systems, traits specific to intercrops and traits related with socioeconomic and seed quality aspects. Screening, prebreeding and recombination nursery are better made under sole cropping while varietal improvement and on-farm trials are conducted under the target multiple cropping systems. Breeding schemes may involve recurrent, pedigree and bulk hybrid selection. The given application concerns the genetic improvement of P. coccineus, P. polyanthus and interspecific hybrids of P. vulgaris for both simultaneous and relay intercropping in Colombia and Peru. Earliness, cold tolerance, resistance to fungus diseases (mainly Ascochyta leaf blight and anthracnosis) and seed yield potential were the major objectives of the bean improvement programme. Priority has been given to the exploitation of the large diversity available in the secondary gene pool of common bean. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
79.
ABSTRACT:   The effects of shrimp head protein hydrolysate (SHPH) from three species of shrimp (northern pink shrimp [ Pandalus eous ], endeavour shrimp [ Metapenaeus endeavouri ], black tiger shrimp [ Penaeus monodon ]) on gel forming ability and protein denaturation of lizardfish surimi during frozen storage at −25°C were evaluated. The quality of lizardfish surimi with 5% (dried matter) of any of the three SHPH or sodium glutamate (Na-Glu) was examined in terms of gel strength, whiteness, Ca-ATPase activity and the amount of unfrozen water, comparing with those of surimi without additive as the control. The residual Ca-ATPase activity and gel strength of surimi with SHPH were higher than those of the control throughout 180 days of frozen storage, regardless of shrimp species. The highest effect was found in surimi with Na-Glu. The gel strength and Ca-ATPase activity found a high positive correlation. The addition of SHPH to surimi also increased the amount of unfrozen water by approximately 1.29–1.36 fold higher than the control, however kamaboko gels of the control was significantly whiter. From these results, freeze-induced denaturation of lizardfish muscle protein could be lessened by the addition of SHPH, resulting in a high gel strength and Ca-ATPase activity.  相似文献   
80.
Summary

The relationship between the intensity of flower colour and changes in the content of the main anthocyanins under various controlled temperatures was examined in order to clarify the effects of high temperature on flower colouration in six pink flower genotypes of greenhouse chrysanthemum (Chrysanthemum morifolium Ramat.). Poor colouration of flowers was observed at 30°C in all genotypes except ‘Chatoo’. This genotype showed little difference in flower colour between different temperature treatments. The degree of change in flower colour differed depending on the genotype, whereas no clear differences in flower colouring were observed between Summer – Autumn flowering and Autumn-flowering genotypes. All genotypes showed lower contents of the two anthocyanins tested [cyanidin 3-O-(6’’-O-monomalonyl- -glucopyranoside) and cyanidin 3-O-(3’’,6’’-O-dimalonyl- -glucopyranoside)] at higher temperatures. Therefore, flower colour changes were attributable to changes in these two main anthocyanins. Differences in colouration between genotypes and temperature conditions were also detectable in values that were measured using a colorimeter. Changed parameters that were visually verifiable were the a* value, representing the degree of red colour, and the C* value, representing chroma. For ‘Sei-Monako’, which showed visually greater differences between temperature treatments, the a* and C* values were low under high temperature conditions. On the other hand, in ‘Chatoo’, the differences detected by eye and those in a* and C* values between temperature treatments were small. In addition, the present results indicate that mean temperature is more important than either day or night temperature in determining the degree of flower colouration.  相似文献   
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