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81.
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Myers JR 《Journal of agricultural safety and health》2010,16(4):265-278
Rollover protective structures (ROPS) are an effective engineering control known to prevent tractor overturn deaths, the leading cause of occupational fatalities for farmers and farm workers in the U.S. However, the use of ROPS is known to vary greatly from farm to farm. A national sample of 11,458 farm operators from the 2004 Occupational Injury Surveillance of Production Agriculture (OISPA) survey was used to assess the association between the prevalence of ROPS and ten farm operator and farm demographic variables using logistic regression. The variable were: operator's age, operator's sex, operator's education, farm sales, full- or part-time farming, acreage, type of operation, number of hired workers, number of injuries, and region. All ten variables were found to have significant associations with the prevalence of non-ROPS tractors on farms in the univariate logistic regressions. For the multivariate model, all variables except for the sex of the farm operator remained significant. Farms with less than three adult injuries, no hired workers, less than 300 acres in size, a Midwest location, and a primary farm type of tobacco, fruit and nuts, dairy, or poultry and eggs all had adjusted odds ratios of 2 or greater. Increasing the prevalence of ROPS-equipped tractors is essential for reducing the leading cause of death on farms, tractor overturns. Economic factors play a major role in the prevalence and distribution of non-ROPS tractors on farms. The identified associations can be used to effectively target areas of the U.S. for ROPS promotion activities. 相似文献
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Early tree growth, crop yields and estimated returns for an agroforestry trial in Goldsboro, North Carolina 总被引:1,自引:0,他引:1
Frederick Cubbage Viola Glenn J. Paul Mueller Daniel Robison Russell Myers Jean-Marie Luginbuhl Ron Myers 《Agroforestry Systems》2012,86(3):323-334
A 17 acre (6.9?ha) agroforestry research and extension alley cropping trial was established at the Center for Environmental Farming Systems in Goldsboro, North Carolina in January 2007, with a randomized block design with five replications. Loblolly pine (Pinus taeda), longleaf pine (Pinus palustris) and cherrybark oak (Quercus pagoda) were planted in staggered rows, with each species planted for 140?ft (43?m) per replication. Crop land alleys of 40?ft or 80?ft (12.2–24.4?m) wide were left between the tree rows. Crops of soybeans (Glycine max) and corn (Zea mays) were planted in alternating years since establishment. As of 2011, survival rates were 93% for cherrybark oak, 88% for longleaf pine and 97% for loblolly pine. Average tree diameter at ground level was 1.0?in (2.5?cm) for cherrybark oak, 2.1?in (5.3?cm) for longleaf and 3.2?in (8.1?cm) for loblolly. Heights averaged 4.6?ft (1.4?m) for cherrybark oak, 5.2?ft (1.6?m) for longleaf pine and 10.4?ft (3.2?m) for loblolly pine. Growth, yield and economic projections for traditional timber production indicated that species volumes and values tracked the height and diameter relationships measured on the site. Loblolly pine had the largest projected internal rate of return, at 7.2%, followed by longleaf pine with pine straw harvests at 5.5%, longleaf without pine straw at 3.5% and cherrybark oak at 1.9%. There might be more loss in crop and silvopasture production with loblolly, however, and production of pine straw for longleaf or game mast for cherrybark oak may offer other benefits. Crop yields on the sandy soils on the site were very poor during the 4?years observed, which had a series of droughts and floods. These led to net financial losses in those years for the demonstration site, but state-wide average farm budget returns did show moderate profits. The results support the merits of agroforestry systems in the upper South to diversify income and reduce financial risks. 相似文献
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R.J.K. Myers 《Soil biology & biochemistry》1975,7(2):83-86
Ammonification of soil organic N and nitrification of ammonium-N was studied in Tindall clay loam over a range of temperatures from 20–60 C. Nitrification rates at each temperature were constant throughout the 28 day incubation, whereas most of the ammonification occurred in the first 7 days. The optimum for nitrification was close to 35 C. exhibiting a sharp peak at this temperature at which the potential rate was 4.8 μg N/g day?1, compared with 0.5 μg N/g day?1 at 20°C and 0.25 μg N/g day?1 at 60°C. The optimum temperature for ammonification was approximately 50°C at which the rate was 2.8 μg N/g day?1 in the first 7 days but only 0.5 μg N/g day?1 between 14 and 28 days.The temperature responses could be described mathematically with functions of the type logoN = k × 1/T.The results are discussed in relation to daily patterns of N mineralization in the field where temperatures show diurnal fluctuation. 相似文献
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Two 12-year-old cats were diagnosed with chronic kidney disease (CKD) based on physical examination, clinicopathologic data and, in one case, abdominal ultrasound findings. Approximately 1 year after the initial diagnosis of CKD both cats developed renal transitional cell carcinoma (TCC)--bilateral in one cat. Based on post-mortem examination, one cat had no evidence of metastasis and the other had metastasis to the large intestine, heart and lungs. This is the first report of de novo bilateral renal TCC in a cat, as well as the first report of renal TCC developing in cats with previous history of confirmed CKD. 相似文献
90.
Phair KA Carpenter JW Smee N Myers CB Pohlman LM 《Journal of zoo and wildlife medicine》2012,43(1):162-167
An 8-yr-old, captive, spayed, female maned wolf (Chrysocyon brachyurus) developed progressive lethargy and weakness over a 24-hr period. Clinical signs included vomiting, recumbency, horizontal nystagmus, possible blindness, pale icteric mucus membranes, and port-wine colored urine. A complete blood cell count revealed severe anemia (packed cell volume [PCV], 6%) and intraerythrocytic piroplasms consistent with a Babesia species. Polymerase chain reaction testing later confirmed babesiosis. The wolf was treated with imidocarb dipropionate, antibiotics, and fluid therapy. A whole-blood transfusion from a sibling maned wolf also was performed. Despite aggressive treatment, the wolf failed to improve and was euthanized. To the authors' knowledge, this is the first documented case of babesiosis in a captive maned wolf in North America. Surveillance of infectious diseases in captive and wild maned wolf populations should be expanded to include screening for Babesia species. Tick control also should be implemented to prevent and decrease transmission of the disease to this endangered species. 相似文献