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991.
? Horticultural substrates composed of equal parts of peat and compost (v/v) were stored for a period of 24 weeks. The chemical properties and the microbial activity were determined periodically for a wet mix (55% moisture), a dry mix (25% moisture) and a wet mix amended with feather meal. Results showed that electrical conductivity and major nutrients increased with the length of the storage period whereas pH, ammonium and minor elements with the exception of manganese were strongly reduced. The pH and the chemical composition of the dry mix were not affected during storage. Feather meal actively stimulated the microorganisms within few weeks and raised electrical conductivity and nitrates at the end of storage. It was concluded that changes which occurred during storage were related to the microbial activity. 相似文献
992.
As a result of increased population, improved standards of living, and strict environmental laws, biowastes have been generated in huge quantities. Thus, land applications of these wastes are desirable, or even necessary, to keep the environment healthy and to conserve natural resources. Yet, the success of such uses requires knowledge of complex biochemical reactions when the wastes are applied to soils. To obtain this knowledge, we evaluated soil amendment properties, primarily nitrogen (N) mineralization/immobilization of six bio wastes when used as plant growth media. An immature yard trimmings compost, ground fresh corn stovers, a commercial peat moss, a chicken manure, and two biosolids were each mixed with a Mollisol at either 25 percent and 50 percent by volume for the plant based wastes, or at 2.5 percent and 5.0 percent by weight for the animal based wastes. Treatments with urea at 0, 70 and 210 mg N kg?1 were included for comparison. The treated soils were incubated moist for two weeks at which time they were sampled for chemical analysis, and planted to tomatoes. The results showed that those wastes, when added to soil, produced growth media with C/N < 15, and released inorganic N that increased dry matter yield of tomatoes many times over that of the unamended control. In contrast, a waste amended soil with a C/N > 20 immobilized some inorganic N, reduced plant growth, and caused N deficiency in tomatoes. Such a deficiency was characterized by low N concentrations in leaves (< 2.0 percent) and chlorosis, which corresponded to a color index of 0.25 or less. Biowaste amendments also affected soil P extractability differently: Chicken manure increased NaHCO3-extractable P many fold over the control, whereas corn stover, peat moss and raw biosolids did not. The yard trimmings compost and the anaerobically digested biosolids increased soil P moderately. 相似文献
993.
994.
Pierre-Yves Le Gal Jennifer Bernard Charles-Henri Moulin 《Tropical animal health and production》2013,45(5):1119-1129
This article investigates how a one-to-one support process based on the use of a whole dairy farm simulation tool helps both farmers to reflect on their production strategies and researchers to better understand the farmers’ contexts of action and decision. The support process consists of a minimum of four discussion sessions with the farmer: designing the Initial Scenario and formulating a diagnosis, building and simulating the Project Scenario corresponding to the objective targeted by the farmer, building and comparing alternative scenarios proposed both by the farmer and the researcher, and evaluating the process with the farmer. The approach was tested with six smallholder farmers in Brazil. It is illustrated with the example of one farmer who aimed to develop his milk production by more than doubling his herd size on the same cultivated area. Two other examples illustrate the diversity of issues addressed with this approach. The first estimates the sensitivity of economic results to price variations of milk and concentrates. The second compares two scenarios in terms of forage supply autonomy. The discussion assesses the outcomes of the approach for farmers in terms of response to their specific issues and of knowledge acquired. The research outputs are discussed in terms of the value and limits of using simulation tools within both participatory action research and advisory processes. 相似文献
995.
Skylar Carlson Laura Marler Sang-Jip Nam Bernard D. Santarsiero John M. Pezzuto Brian T. Murphy 《Marine drugs》2013,11(4):1152-1161
Agents capable of inducing phase II enzymes such as quinone reductase 1 (QR1) are known to have the potential of mediating cancer chemopreventive activity. As part of a program to discover novel phase II enzyme-inducing molecules, we identified a marine-derived actinomycete strain (CNJ-878) that exhibited activity with cultured Hepa 1c1c7 cells. Based on this activity, a new macrolide, juvenimicin C (1), as well as 5-O-α-l-rhamnosyltylactone (2), were isolated from the culture broth of a Micromonospora sp. Compound 1 enhanced QR1 enzyme activity and glutathione levels by two-fold with CD values of 10.1 and 27.7 μM, respectively. In addition, glutathione reductase and glutathione peroxidase activities were elevated. This is the first reported member of the macrolide class of antibiotics found to mediate these responses. 相似文献
996.
997.
998.
G. Charmet N. Robert M.R. Perretant G. Gay P. Sourdille C. Groos S. Bernard M. Bernard 《Euphytica》2001,119(1-2):89-93
We used a computer program to manage marker data in a recombinantinbred line population. The objective was to select pairs of inbred lines tobe intercrossed, in order to cumulate all favourable alleles, either withadditive effects or with interactive effects. The population size required tohave 95% chance of obtaining the best line from a given cross iscomputed, taking into account the number of QTLs and the probability thatno recombination event occurs in any QTL confidence intervals. It is shownthat the accuracy of QTL location greatly affects selection efficiency andthat a recurrent selection scheme is highly preferable for pyramiding manyQTLs. Dough strength (W) was chosen to illustrate the use of this method.In a population of 187 DH lines from the cross Courtot × Chinese Spring,W was found to be controlled by 8 additive QTLs and two pairs ofinteractive QTLs. None of the 187 DH lines possess all favourable allelesor combination of alleles. The best possible line could be produced by asingle cycle of crossing followed by line extraction, but several thousandlines needed to be produced to achieve this goal. Alternatively, a recurrentcrossing scheme allows to obtain the best line in two generations, andrequires less than 150 lines per cycle. 相似文献
999.
Steven B Kleiboeker Susan K Schommer Philip J Johnson Bernard Ehlers Susan E Turnquist Magalie Boucher John M Kreeger 《Journal of veterinary diagnostic investigation》2002,14(4):273-280
Over a period of 6 years, antemortem and postmortem examinations were performed on a number of donkeys suffering from respiratory disease. For many cases, initial diagnostic efforts failed to identify an etiology consistent with the pathologic findings. However, retrospective examination of these cases using consensus primer polymerase chain reaction, designed to recognize herpesviruses from all 3 subfamilies of the Herpesviridae, amplified a fragment of the highly conserved herpesvirus DNA polymerase gene from a number of these animals. Two novel herpesviruses, herein designated asinine herpesvirus 4 (AHV4) and asinine herpesvirus 5 (AHV5), were consistently detected in lung tissue from donkeys in which the histopathology was characterized by interstitial pneumonia and marked syncytial cell formation but not in lung tissue from donkeys with evidence of bacterial or verminous pneumonia. Nucleotide sequence and phylogenetic analysis places these new viruses within the Gammaherpesvirinae subfamily and indicates that they are most closely related to the recently identified zebra herpesvirus and wildass herpesvirus as well as equine herpesviruses 2 and 5. 相似文献
1000.
Mast cell tumors in the dog. 总被引:1,自引:0,他引:1
Cheryl A London Bernard Seguin 《Veterinary Clinics of North America: Small Animal Practice》2003,33(3):473-89, v
The most common skin tumor in dogs is the mast cell tumor (MCT), with an incidence of close to 20% in the canine population. MCTs range from relatively benign to extremely aggressive, leading to metastasis and eventual death from systemic disease. Although surgical removal with or without radiation therapy may cure most patients with low-grade MCTs, there are no effective treatments for dogs with aggressive high-grade MCTs. This article reviews the current understanding of MCT biology with regard to diagnosis, staging, identification of prognostic indicators, and appropriate treatment planning. 相似文献