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61.
Avian semen dilution with appropriate extender allows to prolong the fertilizing ability of sperm stored in vitro. In the present study, the impact of extenders and time of storage on morphology of Muscovy duck (Cairina moschata) drake semen were examined. Semen was collected twice a week, using male stimulation by a female method, from 12 adults (29 weeks old) drakes kept individually in cages, under controlled environmental conditions. Freshly collected, pooled ejaculates were divided into three part: neat undiluted sample, and diluted 1:1 with Schramm (SCH) or Watanabe (W) extender and stored at 4°C. Morphological examination of all samples was conducted after dilution and then, after 3 and 6 hr of storage. The storage of undiluted semen caused decrease (p ≤ .01) in live morphologically normal sperm, from 79.73% in the freshly collected ejaculates to 55.75% and to 12.12% after 3 and 6 hr of storage, respectively (average calculated for the entire reproductive season). In the semen diluted with Schramm's extender the adequate values attained 86.84, 79.65 and 61.66%, and using Watanabe extender 84.77, 83.58 and 75.25%, respectively. The period of semen storage and the type of extender caused significant (p ≤ 0,05; p ≤ 0,01) changes in sperm morphology. The longer period of storage contributed to the decrease in number of morphologically normal sperm, whereas their content in Watanabe extender after 3 and 6 hr of storage was higher (p ≤ .01) than in semen diluted in Schramm extender.  相似文献   
62.
Males of Muscovy duck (Cairina moschata) are mainly used for mule duck production via artificial insemination of females originated from wild mallard duck (Anas platyrhynchos); therefore, the quantity and quality of drake semen play a crucial role. The assessment results of male reaction to sexual stimulation by dummy female and basic semen characteristic (ejaculate volume, sperm concentration and morphology) of 12 individually kept Muscovy drakes carried out during the entire reproductive season are described. The male and period of the reproductive season effect on scored semen traits are documented. In total, 792 individual semen collections and evaluations were performed. The average of positive reaction in the entire reproductive season varied from 90.6% in December and April to 50.0% in July, while for individual males, it varied between 97.1% and 29.0%. Throughout the season, the ejaculate volumes ranged from 0.05 to 2.45 ml, sperm concentration from 0.15 × 109 ml−1 to 4.44 × 109 ml−1, total number of live spermatozoa from 68.0% to 100% and live normal (properly formed, with any deformations) from 51.0% to 99.0%. Our study indicates the necessity of male breeders pre-selection before the onset of the reproductive season, and the need to leave an appropriate number of males to ensure adequate amount of semen for female insemination, especially when using Muscovy drakes (Cairina moschata) for interspecies crossing with Anas platyrhynchos ducks.  相似文献   
63.
Studies were conducted at the deepest location of the meromictic Piaseczno pit lake, southern Poland, which was created in abandoned sulphur opencast. Pearson correlation and PCA were used to established the relationship between the elements and physico-chemical parameters of the water, whereas discriminant test to study vertical and time differentiation of Cd, Pb, Sr, Cu, Zn, Mn, and Fe concentrations. The results indicated both vertical (except Cu and Zn) and time differentiations of studied elements in the lake water. The highest concentrations of Cd, Pb, and Sr were found in the monimolimnion, that of Mn and Fe in the anoxic water. Depth profiles of Cu and Zn did not show any pronounced trend. Pb and Sr distributions in the water were related to alkalinity, Cl? and COD, Cd to alkalinity and Cl?, Mn and Fe to the redox conditions, Mn to water pH, and Fe to the alkalinity. The upper (0–15 cm) layer of the sediment consisted mainly of S (24.2 Atom%), Fe (21.62%), Ca (18.4%), Si (14.3%), and (Al 6.3%) and reflected mainly processes proceeded in the anoxic water-sediment interface. Calculated accumulation coefficients (K d) of the elements in the sediment are discussed.  相似文献   
64.
Few studies exist on the influence of processing methods on structural changes and allergenic potential of hazelnut proteins. This study focused on the effect of glycation (Maillard reaction) on the immunoreactivity and degranulation capacity of the purified hazelnut 7S globulin, Cor a 11. After heating, the extent of the Maillard reaction, sensitivity to proteolysis, binding of human IgE or rabbit IgG, and degranulation capacity were analyzed. Changes in electrophoretic mobility, amount of free amino groups, and contents of bound sugar and fructosamine indicated that glycation of Cor a 11 occurred at all conditions. Glycation at 37 °C did not influence the specific IgG or IgE binding and was decreased after heating at 60 and 145 °C. Heating, with or without glucose, at 145 °C increased basophil degranulation capacity. The results suggest that glycation of Cor a 11 at 60 and 145 °C may decrease the IgE/IgG binding properties but not the degranulation capacity of basophils. This is possibly related to aggregation of the proteins as a result of the Maillard reaction.  相似文献   
65.
The objective of this research was the evaluation of the effects of exogenous added surfactants on hydrocarbon biodegradation and on cell surface properties. Crude oil hydrocarbons are often difficult to remove from the environment because of their insolubility in water. The addition of surfactants enhances the removal of hydrocarbons by raising the solubility of these compounds. These surfactants cause them to become more vulnerable to degradation, thereby facilitating transportation across the cell membrane. The obtained results showed that the microorganism consortia of bacteria are useful biological agents within environmental bioremediation. The most effective amongst all, as regards biodegradation, were the consortia of Pseudomonas spp. and Bacillus spp. strains. The results indicated that the natural surfactants (rhamnolipides and saponins) are more effective surfactants in hydrocarbon biodegradation as compared to Triton X-100. The addition of natural surfactants enhanced the removal of hydrocarbon and diesel oil from the environment. Very promising was the use of saponins as a surfactant in hydrocarbon biodegradation. This surfactant significantly increases the organic compound biodegradation. In the case of those surfactants that could be easily adsorbed on cells of strains (e.g., rhamnolipides), a change of hydrophobicity to ca. 30-40% was noted. As the final result, an increase in hydrocarbon biodegradation was observed.  相似文献   
66.
Kidneys are the main organs regulating water-electrolyte homeostasis in the body. They are responsible for maintaining the total volume of water and its distribution in particular water spaces, for electrolyte composition of systemic fluids and also for maintaining acid-base balance. These functions are performed by the plasma filtration process in renal glomeruli and the processes of active absorption and secretion in renal tubules, all adjusted to an 'activity-rest' rhythm. These diurnal changes are influenced by a 24-hour cycle of activity of hormones engaged in the regulation of renal activity. Studies on spontaneous rhythms of renal activity have been carried out mainly on humans and laboratory animals, but few studies have been carried out on livestock animals. Moreover, those results cover only some aspects of renal physiology. This review gives an overview of current knowledge concerning renal function and diurnal variations of some renal activity parameters in livestock, providing greater understanding of general chronobiological processes in mammals. Detailed knowledge of these rhythms is useful for clinical, practical and pharmacological purposes, as well as studies on their physical performance.  相似文献   
67.
The study demonstrates the application of front face and right angle synchronous fluorescence spectroscopy for the characterization of edible oils. The method enables monitoring of tocopherols, pheophytins, and other fluorescent components in edible oils. Principal component analysis of synchronous fluorescence spectra revealed sample clustering according to the type of oil. Partial least-squares regression was utilized to develop calibration models between fluorescence spectra and total tocopherol content determined by HPLC. The regression models showed a good ability to predict tocopherol content. The best fitting results were obtained for 1% v/v diluted oils and for bulk samples using the entire spectrum, yielding the regression coefficient, r, of 0.991, and root mean square error of cross-validation of approximately 8%. The results presented confirm the capabilities of the fluorescence techniques as a tool for the analysis of edible oils.  相似文献   
68.
69.
Abstract

The potential biological activity of three bacterial strains against the four phytopathogens was examined. The bacterial strains were originated from sewage sludge water extract and from the humic acid solution obtained from the sewage sludge. The fresh bacteria cultures and filtered culture broth were used. The noncoated sugar beet seeds were coated by soaking for 15 min in the liquid culture of bacteria, then they were sown in the sterilized soil inoculated by one of the following types of soil fungus: Aphanomyces cochlioides L3, Phoma betas PH8, Pythium irregulare PIR4, Rhizoctonia solani Z10-2. The test proved that Bacillus amytoliquefaciens O1 / O3 and Flaviomonas oryzihabitans K1 / K2 showed antifungal activity on the artificial medium, but they were not able to effectively suppress fungal pathogens in the soil. The bacteria did not injure sugar beet roots, so they can be regarded as microorganisms that are not harmful to plants. It may be concluded that these bacteria have the potential to support antifungal activity of the humis acid and the sewage sludge extracts.  相似文献   
70.

Presently, there is an intensive search for fungal endophytes to be used in agriculture for the protection and condition improvement of plants and in medicine. We screened for the presence of endophytes in raspberry, which occurs naturally in the Bia?owie?a Forest. The fungal isolates representative of each morphotype were analysed using the molecular markers ITS1 and ITS2. In total, we found 34 taxa of endophytic fungi. The majority were potential pathogens. As many as 27 taxa were found in the leaves of mature plants. No fungi could be isolated from the surface sterilized seeds obtained from these plants. Seedlings were grown from the seeds deposited in the soil seed bank in the Bia?owie?a Geobotanical Station of the University of Warsaw in Bia?owie?a. 8 taxa of endophytic fungi were found in seedlings. It could be due to a possibility of seed infection with these endophytes in soil conditions.

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