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51.
Agriculture is a major cause of non-point source water pollution in the Midwest. Excessive nitrate, phosphorous, and sediment levels degrade the Mississippi River and Gulf of Mexico. In this research we ask, to what extent can citizen involvement help solve the problem of non-point source pollution. Does connecting farmers to farmers and to other community members make a difference in moving beyond the status quo? To answer these questions we examine the satisfaction level of Iowa farmers and landowners with their current conservation measures as a proxy for willingness to change. A survey of 360 conservation minded farmers obtained from a random sample of 75 HUC (Hydrologic Unit Code) 12 Iowa watersheds reveals that 27% of the variance among farmers’ perception of adequacy of their conservation practices is explained by a combination of beliefs about the seriousness of water pollution, personal, civic, and expert connections. The more farmers talk with other farmers the more likely they are satisfied with their conservation efforts. However, the more frequently farmers talk to friends and neighbors that don’t farm, the more likely they are to not be satisfied with their conservation efforts. Further, the more social organizations farmers belong to—e.g., more non-farmers they interact with in a group setting—the more likely they are to be dissatisfied with their level of effort being adequate to protect local water bodies. These findings suggest the personal and civic connections among farmers and communities are important in explaining perceptions of how adequate conservation measures are. These perceptions have implications for farmers’ willingness to go beyond current actions and more actively engage in solving local watershed problems and explain why they may not currently be engaged in additional actions.  相似文献   
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植物生长调节剂对盆栽一品红生长及观赏品质的影响   总被引:2,自引:0,他引:2  
以Sonora Red和Sonora White Glitter两个一品红栽培品种为试验材料,研究了5种不同植物生长调节剂组合对一品红生长及观赏品质的影响.结果表明,与施清水处理相比,各生长调节剂处理均对植株的株高增长速率和株高有一定的抑制作用,均使花头直径和苞叶面积减小,使植株的干重和鲜重降低,但品种间有一定差异. 总体来说,质量分数5.0×10-4的乙烯利喷洒2次(前后约1个月)处理和质量分数5.0×10-4的乙烯利喷施1次后约1个月再用质量分数5.0×10-4的矮壮素+质量分数1.0×10-3的B9喷洒1次处理的效果较好,两处理均对一品红的株高有一定的控制作用,但不影响其观赏品质.  相似文献   
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Anesthetic management of the head trauma patient   总被引:1,自引:0,他引:1  
Objective: To describe the optimal anesthetic management of patients with brain injury, with emphasis on the support of oxygen delivery to the brain, and the effects of anesthetic agents on cerebral perfusion. Data sources: Clinical and experimental studies from both the human and veterinary neuroanesthesia literature. Summary: The management of patients following primary traumatic brain injury (TBI) significantly impacts outcome. Outcome can be improved by strategies that improve oxygen delivery to the brain and prevent cerebral ischemia. Anesthetic agents have widely variable effects on the blood supply to the brain and, therefore, choice of anesthetic agent can influence neurological outcome. Although in the past, anesthetic agents have been selected for their neuroprotective properties, it is increasingly being recognized that the support of cerebral perfusion during anesthesia contributes more significantly to a positive outcome for these patients. Support of cardiorespiratory function is, therefore, highly important when anesthetizing patients with TBI. Conclusion: Choice of anesthetic agent is determined by the extent of brain injury and intracranial pressure (ICP) elevation. Factors that should be considered when anesthetizing head trauma patients include the effects of anesthetic agents on the cardiac and respiratory systems, their effects on cerebral blood flow (CBF), ICP, and possible neuroprotective benefits offered by certain agents.  相似文献   
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Campylobacter is the most common notifiable cause of bacterial gastroenteritis in humans in Ireland. However, epidemiological information is limited. We aimed to describe Campylobacter epidemiology in Ireland and trends over time, to inform future surveillance and research. We reviewed data completeness and described notified cases of campylobacteriosis (2004–2016) by age, sex, geographical area, season and trends over time. We used negative binomial regression to estimate incidence rate ratios (IRR) and adjusted IRR (aIRR) by age group, sex, geographical area and season. We undertook interrupted time‐series analysis by age group and geographical area incorporating terms for trend and period (2004–2010 and 2011–2016). There were 27,034 cases of campylobacteriosis notified between 2004 and 2016. Data were >99% complete for notification date, geographical area, sex and date of birth. Crude annual incidence ranged from 36.2 to 54.4 per 100,000 population. The incidence was higher in, males (aIRR 1.15, 95% confidence intervals (CI) 1.12–1.19), those aged <5 years compared with the lowest incidence age group (45–64 years) (aIRR 4.65, 95% CI 4.43–4.88), other seasons compared with winter and all other areas compared with the north‐east area (aIRR range 1.22–1.71, p‐values <.001). In 2011, we observed a stepped increase in annual crude incidence overall, in both sexes, all age groups and most geographical areas. This pattern was mirrored on time‐series analysis, with significant increases in trend‐adjusted incidences of 30%–45% (p‐values ≤.008) detected for all age groups and 30%–66% (p‐values ≤.012) for seven out of eight geographical areas after 2011. Campylobacter remains the most commonly notified bacterial cause of gastroenteritis in Ireland. With available information, we could not fully explain a stepped increase in incidence observed in 2011. The transition of regional laboratories from culture‐based to molecular‐based Campylobacter diagnostic methods was a possible contributor. However, further investigation is required to fully explain the identified changes.  相似文献   
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European Journal of Plant Pathology - Aflatoxin contamination is common in several crops, including maize, in warm agricultural areas. For over 40&nbsp;years, there have been many efforts to...  相似文献   
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