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131.
A male miniature rough-haired dachshund, presented with episodic haematuria, was found to be a female pseudohermaphrodite. A littermate also had an abnormality of the urogenital tract and their dam had received a progesterone implant during pregnancy. Chromosome analysis of the intersex revealed XX/XY mosaicism in certain tissues. 相似文献
132.
Seventeen horses were dissected and their organs and tissues weighed. The results of these dissections are presented together with comparisons of the data with that already available in the literature. Predictive equations for organs and tissue weights are also given which were derived by comparison of linear and allometric regression models using 4 different body weight indices. 相似文献
133.
Comparing deep drainage estimated with transient and steady state assumptions in irrigated vertisols
Chloride mass balance (steady state or transient state) models are used extensively in Vertisols of Queensland and New South Wales (NSW) in Australia to estimate deep drainage. The aim of this study was to compare deep drainage estimated assuming steady state and transient state conditions with chloride mass balance models in irrigated cotton (Gossypium hirsutum L.)-based farming systems in the lower Namoi Valley of North Western NSW. Drainage was estimated at seven sites, and treatments included rotation crops such as wheat (21–62 mm/year) (Triticum aestivum), sorghum (12–47 mm/year) (Sorghum bicolor) and dolichos (12–21 mm/year) (Lablab purpureus), minimum tillage (62–83 mm/year), where cotton was sown into standing wheat stubble, and conventional tillage where stubble was incorporated (35–78 mm/year). Soil water content was measured with a neutron moisture meter in the 0.2–1.2 m depth. Soil was sampled before sowing and after harvest to a depth of 1.2 m along diagonal transects. The soil chloride concentration was determined by titration with AgNO3. Irrigation water was also analysed for chloride. The deep drainage estimates were compared using regression analysis and students paired t-test. In addition, a paired t-test of the soil chloride concentration before sowing and after harvest was used to determine if the soil chloride flux was either in a steady state or transient state. In 9 out of the 13 data sets (69%), drainage estimated with the models agreed with changes between pre- and post-season soil chloride concentrations. Under frequently irrigated summer crops such as cotton and sorghum and in better structured soils chloride flux reached steady state conditions whereas under partially-irrigated crops or where soil structure was poorer, the chloride flux deviated markedly from steady-state conditions. The latter observation may be due to preferential flow via deep cracks in infrequently irrigated soil. Deep cracking would be due to the more intense shrinking and swelling in partially irrigated soil in comparison with frequently-irrigated crops. Comparison of estimated deep drainage with pre- and post-season soil chloride concentrations showed that the steady state mass balance model best estimated deep drainage under cotton crops which were irrigated more frequently or wheat crops which had better soil structure.
相似文献
T. B. WeaverEmail: Phone: +61-2-67991570Fax: +61-2-67991503 |
134.
Swanson DA Casadevall TJ Dzurisin D Malone SD Newhall CG Weaver CS 《Science (New York, N.Y.)》1983,221(4618):1369-1376
Thirteen eruptions of Mount St. Helens between June 1980 and December 1982 were predicted tens of minutes to, more generally, a few hours in advance. The last seven of these eruptions, starting with that of mid-April 1981, were predicted between 3 days and 3 weeks in advance. Precursory seismicity, deformation of the crater floor and the lava dome, and, to a lesser extent, gas emissions provided telltale evidence of forthcoming eruptions. The newly developed capability for prediction reduced risk to life and property and influenced land-use decisions. 相似文献
135.
Evidence from the Irish Sea basin supports the existence of an abrupt rise in sea level (meltwater pulse) at 19,000 years before the present (B.P.). Climate records indicate a large reduction in the strength of North Atlantic Deep Water formation and attendant cooling of the North Atlantic at this time, indicating a source of the meltwater pulse from one or more Northern Hemisphere ice sheets. Warming of the tropical Atlantic and Pacific oceans and the Southern Hemisphere also began at 19,000 years B.P. These responses identify mechanisms responsible for the propagation of deglacial climate signals to the Southern Hemisphere and tropics while maintaining a cold climate in the Northern Hemisphere. 相似文献
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138.
Disodium acid pyrophosphate (SAPP) is used in the potato industry for preventing after-cooking darkening of cooked and oil-blanched French-fried potato. SAPP-treated potatoes often develop a bitter off-flavor chemical taste due to large amounts of PO4 absorbed from hydrolysis of SAPP solution. SAPP hydrolyzes directly to orthophosphate. Hydrolysis rate depends directly upon temperature and pH of the solution. The best control of after-cooking darkening is attained at pH 5 at 20–25°C. Increasing the concentration of SAPP solution has little effect on its stability at various temperatures and pH, and also made no great improvement on the color of the French-fry strips after par frying. 相似文献
139.
Sprouted Russet Burbank seed potato pieces were exposed from 2 to 14 days at a low concentration of ethylene, lμl l-1, at 20 C. The longer the initial exposure time to ethylene the greater the rate of decline in sprout growth and increase in auxiliary branch growth after removal from ethylene. Sprouts were swollen, with enlarged lenticels and had retarded root development after 6 days’ exposure to ethylene. Root growth was more sensitive to ethylene than sprout growth. The implications of the similarity of sprout growth responses to ethylene under controlled conditions and sprout growth found under stress conditions in storage and field soil are discussed. 相似文献
140.
M. L. Weaver E. Hautala M. Nonaka W. Iritani 《American Journal of Potato Research》1972,49(10):376-382
Tissue selected from the stem- and bud-end of reconditioned tubers having sugar-end disorder was compared by color after frying and chemical composition to tissue removed from the two ends of tubers without sugar-end disorder taken directly from cold storage at 45 F, and after reconditioning 3 weeks at 70 F. Chemical analyses of selected tissue suggested that the dark finish-fry color at the stem-end of sugar-end tubers following reconditioning at 70 F was due to the inability of the physiological systems within the tissue to convert reducing sugars to starch and/or to use these sugars in the respiratory process. Of the components analyzed, only a high reducing sugar content was associated with a dark finish-fry color. Neither sucrose nor free amino acid content was associated with the sugar-end disorder. Extending the reconditioning period at 70 F for sugar-end tubers did not lower the reducing sugar content or the darkening of the stem-end tissue on frying. 相似文献