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51.
To establish the evolutionary association between the equine 1 H7 HA and M genes, phylogenetic analyses of the six internal gene segments of equine 1 influenza viruses (H7N7 subtype) were performed using partial nucleotide sequences. The results demonstrated that five internal genes (PBI, PB2, PA, NP and NS) of equine 1 viruses isolated after 1964 were replaced by those of equine 2 H3N8 viruses. However, the M gene was maintained during the evolution of these equine 1 viruses. These findings suggest a functional association between equine H7 HA and M gene products, most likely M2 protein.  相似文献   
52.
To determine the extent of genetic diversity among isolates of Salmonella enteritidis obtained from outbreaks in Fukuoka Prefecture, Japan, from 1989 to 1994, we analyzed a total of 55 isolates of S. enteritidis obtained from 13 distinct outbreaks with pulsed-field gel electrophoresis. These isolates showed three different patterns in pulsed-field profile with Bln I digestion. The groups A, B and C consisted of three outbreaks isolates (Dice coefficient, F = 1), of seven outbreaks (F = 0.56-0.94) and of three outbreaks (F = 0.65-0.78), respectively. This result suggests that a few limited clonal lines of S. enteritidis were successively causing outbreaks in this area from 1989 to 1994.  相似文献   
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Nitrogenous air pollutants including nitrogen dioxide (NO2), nitric acid (HNO3), nitrate (NO 3 ? ), ammonia (NH3), ammonium (NH 4 + ), and nitrous acid (HONO) were characterized at an urban forested (UF) site in Hiroshima and at a suburban forested (SF) site in Fukuoka, western Japan, using an annular denuder system for 1?year from May 2006 to May 2007 to compare the concentrations and chemical species of atmospheric nitrogenous pollutants between UF and SF sites. The proximity of the urban area was reflected in higher NO2 concentrations at the UF site than at the SF site. NO2 was more oxidized at the SF site because it is farther from an urban area than the UF site, which was reflected in higher concentrations of HNO3 at the SF site than the UF site. HNO3 and acidic sulfate is neutralized by NH3, existing as ammonium nitrate (NH4NO3) and ammonium sulfate [(NH4)2SO4] at the UF site. At the SF site, acidic sulfate is neutralized by NH3, existing as (NH4)2SO4, but NH4NO3, had scarcely formed at the SF site. A much higher HONO concentration was observed at the UF site than at the SF site, especially in winter and spring at night, which could be explained by higher NO2 concentrations at the UF site because of its proximity to an urban area and stagnant meteorological conditions. Atmospheric HONO determination was critical in evaluating the possibility of damage to trees in UF areas.  相似文献   
56.
Keratinocyte differentiation-associated protein, Kdap, is a recently identified small secretory protein that may act as a soluble regulator for the cornification and/or desquamation of keratinocytes. To clarify the role of Kdap in the terminal differentiation of keratinocytes, detailed in situ localisation of Kdap was studied using canine skin with normal, hyperplastic and neoplastic epidermis. In normal canine trunk skin, Kdap was expressed by granular keratinocytes, with polarity to the apical side of the cells, suggesting that canine Kdap is present in lamellar granules, as in humans. Expression of Kdap was widespread in the spinous layers in hyperplastic epidermis, but was undetectable in squamous cell carcinomas. These findings suggest that Kdap is closely related to the delay of terminal differentiation and/or release of cells in hyperplastic epidermis.  相似文献   
57.
To detect and quantify 1,2-dicarboxylate structures in humic acid, a chemical reaction forming fluoresceins from 1,2-dicarboxylates and resorcinol was tested. Resorcinol reacted with humic acid to form products having absorption maxima at about 490 nm. A procedure was then developed for quantitative analysis of the radicals. Eight humic acid samples tested contained 0.4–1.0 mmol/g of 1,2-dicarboxylate structures. The 1,2-Dicarboxylates detected in humic acid were considered as ophthalate homologs.  相似文献   
58.
This paper describes a cycloisomaltooligosaccharide glucanotransferase (CITase)-multilayer-immobilized porous hollow-fiber membrane used as an enzyme bioreactor. Dextran, a substrate with an average molecular mass of 43000, is converted into seven- to nine-glucose-membered cycloisomaltooligosaccharides, effective as a preventive for dental caries, aided by convective transport of the substrate to the vicinity of the enzyme through the pores. Epoxy-group-containing graft chains were uniformly appended onto the surface of pores throughout a porous hollow-fiber membrane by radiation-induced graft polymerization. Subsequently, a diethylamino group was introduced, as an anion-exchange moiety, to the graft chains, which caused the chains to expand toward the interior of the pores due to mutual electrostatic repulsion. The expanding graft chain provided multilayer binding sites for CITase. Fifty-five milligrams of adsorbed CITase per gram of membrane is equivalent to the degree of multilayer binding of 5. Finally, 80% of the multilayer-adsorbed CITase was immobilized via enzymatic cross-linking with transglutaminase to prevent the leakage of enzymes. CITase, with a degree of multilayer immobilization of 4, produced the target cycloisomaltooligosaccharides at a conversion yield of 55% in weight at 310 K during permeation by the dextran solution at a space velocity defined as the permeation rate divided by membrane volume of 6 per hour.  相似文献   
59.
In the semiarid Loess Plateau region of China, ecosystems are frequently affected by water shortages. Late spring and early summer are periods when forest communities tend to suffer from soil drought. To clarify the water-use strategies of the main species in this area, the xylem sap flow of trees from three species in the field was monitored for three successive periods in summer using Granier-type thermal dissipation probes. Vapor pressure deficit (VPD), solar radiation (Rs) and soil moisture had varying influences on sap flux density (Fd) in the species. Normalized Fd values could be fitted to VPD using an exponential saturation function, but the fit was better with a derived variable of transpiration (VT), an integrated index calculated from VPD and Rs. From differences in model coefficients, the species were roughly divided into two types with contrasting drought sensitivity. The exotic Robinia pseudoacacia was defined as drought-sensitive type. It showed higher sapflow increases in response to rainfall, suggesting a high water demand and high influence of soil water conditions on transpiration. This species showed relatively late stomatal response to increasing VPD. The wide-peak pattern of diurnal sapflow course also suggests relatively low stomatal regulation in this species. The drought-insensitive type consisted of the naturally dominant Quercus liaotungensis and an indigenous concomitant species, Armeniaca sibirica, in the forest. The sap flow of these species was not very sensitive to changes in soil water conditions. The results suggest that typical indigenous species can manage the water consumption conservatively under both drought and wet conditions. Variations in water use strategies within indigenous species are also detected.  相似文献   
60.
One of the authors, Kumada 1) has found that absorption spectra of podzol humic acids, remarkably different from the other soil humic acids, have fairly distinct absorption bands near 620, 570 and 450 mµ, and he tentatively named them. P type humic acid. P type humic acid seems specific not only in its visible absorption spectra, but also in infra. red absorption spectra, in susceptible to electrolytes, etc. The authors are now engaged in the study of the nature and properties of P type humic acid, and recently they have found that it is composed of at least two main fractions, the one is reddish brown, and the other green, in alkaline solution. The experimental results are briefly presented.  相似文献   
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