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961.
Universities are our responsibility 总被引:1,自引:0,他引:1
Danforth WH 《Science (New York, N.Y.)》1995,269(5231):1651
962.
Abelson PH 《Science (New York, N.Y.)》1995,267(5195):155
963.
964.
965.
Abstract Extract A 15-year-old pony mare developed firm irregular bony swellings on all four legs. These were most severe around the carpal and fetlock joints of the forelegs, restricting both flexion and extension. Over about 6 months the horse had periodic bouts of coughing. She showed moderate weight loss and a depressed demeanour. 相似文献
966.
Mycobacterium bovis was probably introduced into New Zealand with cattle imported in the early 19th century. A tuberculosis control programme was introduced for cattle in 1945. However, the control of tuberculosis in cattle and deer in New Zealand over the past two decades has been hampered by the presence of an important wildlife reservoir, the Australian brushtail possum (Trichosurus vulpecula). While the importance of this source of infection has been suspected by the Ministry of Agriculture for some time, scientific proof has been lacking until recently. A new control programme is currently being finalized with the following objectives: to reduce the prevalence of herd infection in vector free areas to internationally accepted levels, to prevent the establishment of tuberculous vectors in new areas, to decrease the number and size of existing areas where tuberculous vectors exist, and to encourage land-owners to take action against tuberculosis on their properties and in their herds. 相似文献
967.
968.
E. Adipala J. P. Takan M. W. Ogenga-Latigo 《European journal of plant pathology / European Foundation for Plant Pathology》1995,101(1):25-33
Effect of plant density (37,037, 44,444 and 55,555 plants/ha) on the increase of northern leaf blight in time and space on two maize cultivars planted at spacings of 90, 75 and 60 between rows and 30 cm within rows was investigated.Exserohilum turcicum infested maize residue was used as an inoculum source. Maize density did not significantly affect the disease indices, but significantly influenced the grain yield of the two cultivars. In contrast, the two cultivars differed significantly (P0.01) in disease severity, but not grain yield. Higher disease severities and grain yields were associated with higher plant densities, whereas the apparent infection rate was lower in higher plant density. Distance from the maize residue (inoculum source) significantly influenced disease severity. The percentage leaf area blighted, area under disease progress curve and disease progress curve intercept decreased with distance from the maize residue area, but the apparent infection rate on EV8429-SR appeared to increase with distance. Disease gradients (b) were higher in closely planted maize and flattened with time in one location only. 相似文献
969.
Evans EW Harmon BG 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1995,24(4):109-116
Cationic antimicrobial peptides are present throughout the plant and animal kingdoms and bear striking structural and functional similarities across species lines. They provide primitive, nonspecific means of combating a variety of bacteria, fungi, enveloped viruses, and protozoa. Some are also cytotoxic against host cells, including neoplastic cells. Cationic antimicrobial peptides may play various roles in inflammation and tissue repair. Antimicrobial peptides are found in epithelial tissues regularly exposed to microbial attack as well as in cells whose primary function is defense against potential pathogens. They constitute an important part of the nonoxidative antimicrobial arsenal of leukocytes. They are preformed and/or readily synthesized when the cells are stimulated by exposure to pathogens. They exert their effects directly by inserting into membranes of target cells and forming ion channels which increase membrane permeability; however, antimicrobial peptides can also act as opsonins to facilitate phagocytosis. Resistance to defensins is a virulence factor for organisms such as Salmonella sp. The study of cationic antimicrobial peptides is increasing our understanding of innate immunity, inflammation, and the pathogenesis of genetic diseases such as specific granule disease in humans. Therapeutic applications of antimicrobial peptides are currently under investigation. 相似文献
970.
Thoresen SI Tverdal A Havre G Morberg H 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》1995,24(4):129-133
To assess changes in 24 blood constituents in frozen serum and heparinized plasma, blood samples were drawn from 10 clinically normal German Shepherd army dogs. The storage characteristics of nine enzymes (ALP, ALT, amylase, AST, CK, GGT, GLDH, LDH, lipase), and 15 metabolites and minerals (albumin, bile acids, bilirubin, calcium, cholesterol, creatinine, fructosamine, glucose, magnesium, phosphate, potassium, protein, sodium, triglycerides, urea) were studied. Parallel samples of serum and heparinized plasma were stored for 90 and 240 days at two different storage temperatures, -200 degrees C and -700 degrees C. Sixteen of the 24 analytes (ALP, ALT, amylase, AST, CK, GGT, GLDH, LDH, bile acids, calcium, cholesterol, creatinine, fructosamine, magnesium, phosphate, urea) showed statistically significant (p < 0.05) changes during the storage period related to storage time, storage temperature, and sample type. Seven of the analytes (amylase, GGT, GLDH, LDH, bile acids, fructosamine, magnesium) showed changes of possible clinical importance with mean differences from baseline larger than 20% for the enzymes and 10% for the metabolites and minerals during the storage periods. 相似文献