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<正>Rhode岛三分之二的居民全部或部分以地下水作为饮用水.所以保护该岛的地下水资源的责任就落在了州及地方政府身上.对Rhode的环境管理局来说,地下 相似文献
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Production in the western Bering Strait is estimated at 324 grams of carbon per square meter per year over 2.12x 10(4) square kilometers. An ice-reduced growing season makes this large amount of primary production unexpected, but it is consistent with the area's large upper trophic level stocks. The productivity is fueled by a cross-shelf flow of nutrient-rich water from the Bering Sea continental slope. This phytoplankton production system from June through September is analogous to a laboratory continuous culture. 相似文献
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Timmer CP 《Science (New York, N.Y.)》1979,205(4404):385-386
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Friedman DB Kanwat CP Headrick ML Patterson NJ Neely JC Smith LU 《Zoonoses and public health》2007,54(9-10):366-375
Inappropriate use of antibiotics in humans and animals contributes to decreased antimicrobial susceptibility in bacteria of medical importance. Resistant bacteria being transferred from animals to humans are causing public health concern. In-person interviews were conducted with 20 dairy farmers in rural counties of South Carolina to determine farmers' knowledge and attitudes about prudent antibiotic use among livestock. Four focus groups (n = 22) were also conducted to ascertain farmers' specific information needs about proper antibiotic use. Survey results showed that participants (100%) typically determined a need for antibiotic treatment using symptom assessment and reported following some form of operating procedures regarding administration of antibiotics. Few farmers (32%) had actual written antibiotic protocols. Preferred information sources about antibiotics were veterinarians (100%) and other dairy farmers (50%). Most farmers (86%) were not concerned that overuse of antibiotics in animals could result in antibiotic resistance among farm workers. Qualitative analysis of focus groups revealed significant barriers to following proper antibiotic procedures including limited finances and lack of time. The need for bilingual educational resources for Hispanic/Latino dairy workers was expressed. Desired formats for educational materials were posters, flowcharts, videos, and seminars. Education of South Carolina dairy farmers by veterinarians and public health professionals on the appropriate use of antibiotics in dairy cattle is needed to ensure antibiotic effectiveness in both animals and humans. 相似文献
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Ray KA Warnick LD Mitchell RM Kaneene JB Ruegg PL Wells SJ Fossler CP Halbert LW May K 《Preventive veterinary medicine》2007,79(2-4):204-223
The objective of this study was to determine the prevalence of antimicrobial resistance among Salmonella isolated from dairy herds in New York, Minnesota, Michigan, and Wisconsin, USA. Serogroup and antimicrobial susceptibility characteristics were determined for Salmonella from cattle and environmental samples collected during August 2000–October 2001 as part of a longitudinal study where 129 herds were visited at 2-month intervals. Salmonella isolates were tested (using a broth microdilution method) for susceptibility to amoxicillin/clavulanic acid, ampicillin, ceftiofur, ceftriaxone, cephalothin, chloramphenicol, ciprofloxacin, gentamicin, kanamycin, nalidixic acid, streptomycin, sulfamethoxazole, tetracycline, and trimethoprim/sulfamethoxazole. Of the 1506 isolates tested for minimum inhibitory concentrations to these 14 antimicrobial agents, 81.2% were pan-susceptible and for most herds (81.6%) the predominant antimicrobial resistance pattern was pan-susceptible. At least 1 Salmonella isolate resistant to 5 or more antimicrobial agents was found on 23.6% of herds. This resistance phenotype was most common among serogroups B and E1 and among samples from calves and farmer-designated sick cows. Resistant samples most frequently exhibited resistance to tetracycline, streptomycin, and/or ampicillin. No samples were resistant to ceftriaxone (though 13 were in the intermediate range), and very few samples were resistant to ciprofloxacin (n = 1), nalidixic acid (n = 5), or trimethoprim/sulfamethoxazole (n = 7). 相似文献
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Jacobs SR Forrester CP Yang J 《The Canadian veterinary journal. La revue veterinaire canadienne》2001,42(1):45-46
Fecal samples (1216) were collected from dogs presented to 15 veterinary practices across Canada and tested for Giardia by ELISA for group-specific antigen. If positive, the presence of Giardia was confirmed by microscopy. Eighty-eight submissions tested positive by ELISA and microscopy. The overall prevalence rate of Giardia was 7.2%. 相似文献
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Twenty-four specific pathogen-free cats were inoculated with 3 x 10(3) infectious units of a field isolate of Chlamydia psittaci on to the corneal surface. Seven days later they were assigned randomly to three groups of eight and treated orally for 19 days with either clavulanic acid-potentiated amoxycillin, doxycycline or a placebo. Both treated groups responded rapidly, with a marked reduction in isolation rates and clinical scores which were significantly lower than in the placebo group within two and four days, respectively. After two days the group treated with potentiated amoxycillin had a significantly lower isolation score than the group treated with doxycycline. Forty days after they were infected the clinical signs recurred in five of the eight cats treated with potentiated amoxycillin, but a four-week course of potentiated amoxycillin resulted in a complete clinical recovery with no evidence of a recurrence for six months. 相似文献