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31.
What is new about new forest owners? A typology of private forest ownership in Austria 总被引:1,自引:5,他引:1
With structural changes in agriculture, new types of forest owners have become increasingly important. This article develops
an empirically-based typology of forest owners in Austria. Based on a representative survey and by means of cluster analysis,
seven types of forest owners are identified. These types form a sequence, ranging from forest owners with a strong agricultural
background to forest owners with no agricultural background at all. The latter exhibit markedly different behaviour in various
respects, e.g. in their interest in forest-related information. The increasing number of ‘new’ forest owners raises important
questions for forest policy, especially how policy instruments can reach these owners and how extension services can address
them. 相似文献
32.
Extraction and characterization of oil bodies from soy beans: a natural source of pre-emulsified soybean oil 总被引:1,自引:0,他引:1
Iwanaga D Gray DA Fisk ID Decker EA Weiss J McClements DJ 《Journal of agricultural and food chemistry》2007,55(21):8711-8716
Soybeans contain oil bodies that are coated by a layer of oleosin proteins. In nature, this protein coating protects the oil bodies from environmental stresses and may be utilized by food manufacturers for the same purpose. In this study, oil bodies were extracted from soybean using an aqueous extraction method that involved blending, dispersion (pH 8.6), filtration, and centrifugation steps. The influence of NaCl (0-250 mM), thermal processing (30-90 degrees C, 20 min) and pH (2-8) on the properties and stability of the oil bodies was analyzed using zeta-potential, particle size, and creaming stability measurements. The extracted oil bodies were relatively small ( d 32 approximately 250 nm), and their zeta-potential went from around +12 mV to -20 mV as the pH was increased from 2 to 8, with an isoelectric point around pH 4. The oil bodies were stable to aggregation and creaming at low (pH = 2) and high (pH >/= 6) pH values but were unstable at intermediate values (3 = pH = 5), which was attributed to their relatively low zeta-potential. The oil bodies were stable to aggregation and creaming at relatively low salt concentrations (NaCl = 25 mM, pH 7) but were unstable at higher values as a result of electrostatic screening effects. The oil bodies were stable to thermal processing from 30 to 90 degrees C (0 mM NaCl, pH 7), but there appeared to be a change in their interfacial properties (decrease in zeta-potential) at temperatures exceeding 60 degrees C. These results suggest that oil bodies extracted from soybeans have similar or improved stability compared to soybean oil emulsions produced from bulk ingredients and may provide a new way of creating functional soy products for the food industry. 相似文献
33.
Bone marrow necrosis associated with pancytopenia in a cow 总被引:1,自引:0,他引:1
34.
Eighteen male Holstein calves were divided into groups of three and inoculated intratracheally with 5 x 10(9) logarithmic phase or ultraviolet light-killed Pasteurella haemolytica biotype A serotype 1. Serial coagulation profiles were done on one calf from each group during the first 24 hours after inoculation. One calf from each group was necropsied at 4, 12, and 24 hours after inoculation and lesions were characterized with light and transmission electron microscopy. We found that 1) the pulmonary intravascular macrophage may have an important role in the early intravascular inflammatory events; 2) there was morphologic evidence for local initiation of the coagulation cascade in the lung early in the disease process but it was not a consumptive process; and 3) killed-bacteria were capable of causing fibrin exudation, platelet aggregation and alveolar epithelial damage similar to live bacteria, but the degenerative changes in neutrophils, endothelial cells and intravascular fibrin formation that occur with live bacteria were not seen. 相似文献
35.
Detection of bovine papillomavirus DNA in equine sarcoids using the polymerase chain reaction (PCR)]
Unfixed and formalin-fixed frozen sections and paraffin-sections of histopathologically confirmed sarcoids of 20 horses were studied in the PCR. The used set of primers was located in the E5 open reading frame fitting both to bovine papillomavirus 1 (BPV-1) and BPV-2. Independent of the quality of the used tissues BPV-DNA was detected in all 20 sarcoids. By cleaving with restriction endonuclease Bst XI it was shown that the DNA-sequences amplified by PCR were identical with that of BPV-1. The results support the general view that BPV play an important role in equine sarcoids. 相似文献
36.
It is frequently assumed that, in general, combinations of antibiotics and similar chemotherapeutic agents are more efficient than the single chemotherapeutic, and that they can be combined without disadvantages for the activity of the single component. However, the specific properties of the combined substances, such as their antimicrobial spectrum and resistance, their pharmacokinetics and side effects, as well as their physical properties and formulation, have an enormous impact on the activity of combined chemotherapeutics. They may lead to an advantageous, but also to an indifferent or diminished activity of the combination in patients. Some of the important requirements for an advantageous combination of antibiotics and similarly functioning compounds will be reviewed and ways of avoiding mistakes are described. 相似文献
37.
Drug-associated aplastic anemia in dogs: eight cases (1984-1988) 总被引:1,自引:0,他引:1
Records of 8 dogs with drug-associated aplastic anemia were reviewed. Drugs suspected as being causative included estradiol cyclopentylpropionate (3 dogs), phenylbutazone (2 dogs), meclofenamic acid (1 dog), trimethoprim-sulfadiazine and fenbendazole (1 dog), and quinidine (1 dog). Five of the dogs died or were euthanatized. One dog with estrogen-associated aplasia recovered after prolonged treatment. The dogs with trimethoprim-sulfadiazine and quinidine-associated marrow aplasia recovered promptly after treatment was discontinued. 相似文献
38.
Epistomatal wax structure, occurrence of dust, gypsum-crystallites and microorganisms on the needle surfaces and trace metal contents of current-year Norway spruce needles from various Austrian sites with different pollution levels and sources were analyzed. The epistomatal wax structure was assessed with a recently developed quantification method. Generally, sites in the vicinity of various emissions sources (e.g steel works, chemical industry, magnesite/cement works, highways, conurbations) showed significantly stronger degraded wax structures than sites remote from sources. However, between the individual categories of emitters hardly any difference in the degree of the observed wax degradation could be stated. Various pollutants or emission types seem to cause epistomatal wax degradations. For these findings the following methodological prerequisites which were derived from results of the present monitoring survey were taken into account: the epistomatal wax structures of identical trees were found being significantly different between sampling years. The reasons in behind need further clarification. Therefore only data from the same sampling year should be used for site comparisons in relation to pollution status. The occurrence of mechanical abrasions of surface waxes (which may be caused by the steadily rubbing of needles through heavy wind events) was identified as a further excluding factor for site comparisons. Dust particles and gypsum-crystallites were only detected on needles from sites located in the vicinity of emission sources, whereas the occurrence of microorganisms on the needle surfaces was not related to the vicinity of pollution sources. Several heavy metals were found in elevated concentrations in needles close to respective sources (steel works: Fe, Mn, Zn, Pb, Hg; metallurgical works: Fe, Mn, Ni, Mo, Cr, V; highways: Zn, Cu, Pb). Some of these metals (Fe, Mn, Zn, Cu, Cr, V) were also detected in the dust adhering to the needle surface. These results and the relation of higher contents to the denser covering of the needles with dust suggest that recently deposited adhering dust particles are responsible for the higher elemental contents measured in the needles. In contrast to these needle surface parameters, the epistomatal wax quality did not show any relation to the concentration of the investigated heavy metals. 相似文献
39.
Prinn RG Huang J Weiss RF Cunnold DM Fraser PJ Simmonds PG McCulloch A Harth C Salameh P O'Doherty S Wang RH Porter L Miller BR 《Science (New York, N.Y.)》2001,292(5523):1882-1888
The hydroxyl radical (OH) is the dominant oxidizing chemical in the atmosphere. It destroys most air pollutants and many gases involved in ozone depletion and the greenhouse effect. Global measurements of 1,1,1-trichloroethane (CH3CCl3, methyl chloroform) provide an accurate method for determining the global and hemispheric behavior of OH. Measurements show that CH3CCl3 levels rose steadily from 1978 to reach a maximum in 1992 and then decreased rapidly to levels in 2000 that were lower than the levels when measurements began in 1978. Analysis of these observations shows that global OH levels were growing between 1978 and 1988, but the growth rate was decreasing at a rate of 0.23 +/- 0.18% year(-2), so that OH levels began declining after 1988. Overall, the global average OH trend between 1978 and 2000 was -0.64 +/- 0.60% year(-1). These variations imply important and unexpected gaps in current understanding of the capability of the atmosphere to cleanse itself. 相似文献
40.
R Weiss 《Science (New York, N.Y.)》1991,252(5010):1059-1060