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S A McLaughlin A H Brightman L C Helper J P Manning J E Tomes 《Journal of the American Veterinary Medical Association》1983,182(3):241-242
In 123 cases of external ocular disease in the horse, pathogenic microorganisms isolated with greatest frequency were Streptococcus sp (43.9%), Staphylococcus sp (24.2%), and Pseudomonas sp (13.8%). Fungi were isolated in 4.8% of the cases. In vitro testing showed that most of the Streptococcus sp isolants were sensitive to ampicillin, cephalothin, and carbenicillin. Most of the Staphylococcus sp isolants were sensitive to gentamicin, cephalothin, and bacitracin. Most of the Pseudomonas sp isolants were sensitive to polymyxin B and gentamicin. 相似文献
454.
Curtis Wells Dewey DVM MS Cleta Sue Bailey G. Diane Shelton Philip H. Kass G. H. Cardinet III 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1997,11(2):50-57
The purpose of this project was to investigate the clinical forms of acquired myasthenia gravis in dogs. The medical records from 25 dogs with seropositive acquired myasthenia gravis were reviewed, and the following data were recorded for each patient: signalment, history, clinical findings; results of IV edrophonium chloride administration, repetitive nerve stimulation, and presence or absence of muscle membrane staining by immunocytochemical methods; serum acetyl-choline receptor antibody concentration; treatment; and outcome. Several clinical forms of acquired myasthenia gravis were identified. Nine of the 25 patients (36%) had no historical or clinical evidence of appendicular muscle weakness, and were designated as focal myasthenics. These dogs exhibited focal weakness in one or more of the following muscle groups: facial {3 of 9), pharyngeal (3 of 9), and laryn-geal (3 of 9). The remaining 16 dogs (64%) exhibited appendicular muscle weakness. Four of these 16 dogs had acute onset and rapid development of clinical signs, and were designated as acute fulminating myasthenics. The remaining 12 dogs were classified as generalized myasthenics. All 4 dogs with acute fulminating myasthenia gravis had megaesophagus, 2 had facial muscle weakness, and 1 had pharyngeal muscle weakness. Ten of the 12 dogs with generalized myasthenia gravis had megaesophagus, 4 had facial muscle weakness, 4 had pharyngeal muscle weakness, and 3 had laryngeal muscle weakness. Historical or clinical evidence of exercise-associated appendicular weakness was found in only 6 of the 12 (50%) dogs with generalized myasthenia gravis, and in none of the dogs with acute fulminating myasthenia gravis. Seven of the 12 dogs with generalized myasthenia gravis had weakness primarily (n = 1) or exclusively (n = 6) of the pelvic limbs. Two of the 4 dogs with acute fulminating myasthenia gravis had primarily pelvic limb weakness. Twelve of the 25 dogs (48%) died or were euthanized shortly after admission to the hospital due to aspiration pneumonia. The dogs with acute fulminating myasthenia gravis had a markedly higher 1-year mortality rate in comparison with the other 2 groups. The use of immunosuppressive therapy had a significant positive effect on patient survival, regardless of the type of myasthenia gravis. This investigation demonstrates that acquired myasthenia gravis in dogs is a disorder with a wide spectrum of clinical forms, similar to the analagous disorder in people. 相似文献
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456.
Evaluation of Campylobacter jejuni colonization of the domestic ferret intestine as a model of proliferative colitis 总被引:2,自引:0,他引:2
Forty 3- to 17-week old domestic ferrets, including 2 gnotobiotes, were inoculated orally and/or rectally with 10(6) to 10(9) colony-forming units of 1 or more of 4 strains of Campylobacter jejuni, 3 of mink and 1 of human origin. Feeding or gavage of any of the 4 strains, in milk or broth, with or without preinoculation sodium bicarbonate treatment to neutralize stomach acid, induced colonization in 38/40 ferrets; diarrhea lasted 2 to 4 days in conventional kits, 6 days in gnotobiotes. Bacteremia was detected in 4 of 18 tested, 2 to 5 days after inoculation. Two strains caused no more severe disease or prolonged colonization after 3 serial IV passages in kits than they did before passage. Multiple inoculations with a given strain resulted in progressively briefer colonization and milder disease, but subsequent inoculation with a different strain induced colonization and gastrointestinal disease similar to a primary infection. Five kits inoculated rectally after 4 previous homologous inoculations were resistant to colonization as well as to disease. Agglutinin titers of ferrets inoculated orally or rectally once were low or undetectable, but increased in response to repeated inoculation. Pretreatment with a 1% formalin enema caused mild colon irritation without clinical or histologic evidence of proliferative colitis in ferrets concurrently inoculated orally and/or rectally, whether or not they had preexisting antibodies to any strain of C jejuni. Histologic examination of tissues revealed leukocytic infiltration of intestinal lamina propria in 29 of 35 infected kits and 5 of 8 noninfected controls, and cryptosporidiosis in 5 infected kits plus 1 control.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
457.
T O Manning N A Monteiro-Riviere D G Bristol J E Riviere 《American journal of veterinary research》1991,52(12):1960-1964
The assessment of cutaneous microcirculation by laser-Doppler velocimetry (LDV) has been primarily limited to human studies. The purpose of this investigation was to establish normal values in various species and anatomic sites for blood flow, velocity, and volume as determined by LDV. Microcirculation was measured with a laser-Doppler velocimeter in 54 animals, 6 healthy animals from each of 9 species. The standard sites used were the buttocks, convex surface of the ear, metacarpal pad, humeroscapular junction, thoracolumbar junction, ventral portion of the abdomen, dorsal metacarpus (hooved animals), and ventral surface of the tail (horse). Significant differences in blood flow, velocity, and volume were measured between species and sites within species. The ventral portion of the abdomen consistently had the highest relative blood flow across all species except the monkey. Measurements in the canine metacarpal pad had a high SD, possibly indicating the stratum corneum and epidermis to be too thick for LDV. Our findings provide baseline data in several species, with application of LDV in comparative dermatologic research. 相似文献
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459.
Land-use changes and sustainable development in mountain areas: a case study in the Spanish Pyrenees
José M. García-Ruiz Teodora Lasanta Purificación Ruiz-Flano Luis Ortigosa Sue White Constanza González Carlos Martí 《Landscape Ecology》1996,11(5):267-277
Land-use changes affecting Mediterranean mountains represent the intensification of use in valley bottoms, accompanied by land-use conflicts, and a generalized abandonment of the hillslopes, which in the past were perfectly integrated in the system of land management. Farmland abandonment, reforestation, diminution of the livestock pressure and substitution of cereal crops by meadows are the most outstanding features of the recent land-use changes. The question is whether the new spatial organisation is in accordance with a longterm policy of sustainable development in mountain areas. The results obtained confirm that farmland abandonment on steep slopes — and the resulting colonization of old fields by a dense shrub cover — and afforestation contribute to control both soil erosion and surface runoff. As a result some of the most important rivers and alluvial fans have recently stabilized their sedimentary structures. 相似文献
460.