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81.
Separation of skin reactive intestinal cancer antigen from the carcinoembryonic antigen of Gold 总被引:1,自引:0,他引:1
A C Hollinshead C G McWright D H Alford TC GLEW P Gold R B Herbeman 《Science (New York, N.Y.)》1972,177(52):887-889
Soluble fractions of human intestinal cancer and fetal intestinal cell membranes produced delayed hypersensitivity reactions in patients with intestinal cancer. These soluble fractions and perchloric acid extracts of intestinal cancer cells were fractionated by polacrylamide-gel electrophoresis. The Gold carcinoembryonic antigen was found in a region of the gels different from that of the skin reactive antigen. 相似文献
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Harry H. Schomberg Dinku M. Endale Michael B. Jenkins Dwight S. Fisher 《Biology and Fertility of Soils》2011,47(7):823-831
Poultry (Gallus gallus domesticus L.) litter (PL) is a readily available nutrient source for crop production in the Southeast USA. Long-term PL application
may alter availability of N and the effect may be dependent on tillage practice. Tillage [no till (NT) vs. conventional (CT)]
and N source (PL vs. commercial fertilizer CF) effects on N availability and plant uptake were evaluated in years 9, 10, and
11 of a long-term cropping systems study at the United States Department of Agriculture, Agricultural Research Service, J.
Phil Campbell Sr. Natural Resource Conservation Center, Watkinsville, GA, USA. Mineral N in the top 10 cm, measured in situ,
varied each year and was influenced by time, tillage, and N source. In 2003 (year 9), soil mineral N content was greater in
CT–CF (100 kg ha−1) than in NT–PL (95 kg ha−1) but in 2004 (year 10) and 2005 (year 11) it was lower in CT–CF (93 and 60 kg ha−1) compared to NT–PL (140 and 71 kg ha−1). Nitrogen mineralization rates were generally greater for PL than for CF treatments with the difference being almost 1 kg ha−1 day−1 in 2003. Mineralization rates were greater for NT–PL compared to CT–CF in 2004 and 2005. Across the three growing seasons,
corn (Zea mays L.) aboveground biomass was consistently greater in the NT–PL treatment than in the NT–CF and CT–CF treatments. Correlation
between aboveground biomass and N mineralization was greater for PL than for CF (0.75 vs. 0.48). Patterns of N mineralization
and total soil mineral N indicated that the distribution of N through the growing season more closely matched corn N demand
in PL treatments. Results indicate that improved N availability through the growing season, by combining NT and PL, can result
in more profitable corn production in the southeast. 相似文献
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Backcrossed chromosome substitution lines (CS‐B) have been developed with a homologous pair of chromosomes or chromosome arms of Gossypium barbadense (3‐79) germplasm substituted for the homologous Gossypium hirsutum(TM‐1) chromosomes or chromosome segments. We report on agronomic and fibre trait performance of four backcrossed chromosome or chromosome arm substitution lines including chromosomes 01, 11sh (chromosome 11 short arm), 12 sh and 26 Lo (chromosome 26 long arm). Data for agronomic and fibre traits were collected from replicated field experiments at two different locations in 2 years, and analysed under an additive dominance genetic model. CS‐B 12sh had higher, while CS‐B 01 and CS‐B 26Lo had lower boll weight than TM‐1. The presence of significant negative additive effects for micronaire with CS‐B 01 and significant positive additive effects for elongation and fibre strength with CS‐B 11sh suggested the substituted chromosome arms of 3‐79 in these CS‐B lines were more likely carrying genes causing these effects. Results revealed that several CS‐B lines had significant homozygous and heterozygous dominance effects for different agronomic and fibre traits suggesting that specific CS‐B lines may be useful for improving agronomic and fibre traits in hybrid cottons. These CS‐B lines also provide novel genetic resources for improving upland cotton germplasm. 相似文献
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When perennial ryegrass and wild white clover are grown in a phosphorus-deficient soil, there is a difference in the extent to which they use the added phosphorus, especially when the phosphorus supply (potential) is small. In these circumstances the clover makes the better use of the phosphorus. The similarity of the Larsen values obtained with these two species, however, indicates that this must be largely due to the species absorbing the phosphorus at different rates, and not to any interspecific difference in ability to utilize the supply. Both perennial ryegrass and cocksfoot gave higher L values for the hay than for the pasture variety, indicating that slowly-exchangeable phosphorus might be more accessible to the former than the latter. Perennial ryegrass, cocksfoot, timothy, wild white clover and red clover showed minimum values for L at varying times after sowing which were characteristic of the species. This is explained in terms of the isotopic exchange reactions taking place. 相似文献