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101.
102.
Abstract Regurgitated pellets were collected from underneath roosts of rainbow bee-eaters in suburban Darwin, Australia, and examined for the presence of wings of honeybees. The proportion of pellets containing wings was compared prior to and after placement or removal of honeybee hives in the vicinity of four roosts. On each occasion, the addition or removal of hives was reflected in proportions of pellets containing wings. The results suggest that examination of pellets beneath bee-eater roosts would be a useful technique for monitoring the occurrence of feral honeybees. Potential uses for this technique in eradication of unwanted bees are discussed. 相似文献
103.
Alberto Giubilini Thomas Douglas Hannah Maslen Julian Savulescu 《Developing world bioethics》2018,18(2):182-189
We address the issue of whether, why and under what conditions, quarantine and isolation are morally justified, with a particular focus on measures implemented in the developing world. We argue that the benefits of quarantine and isolation justify some level of coercion or compulsion by the state, but that the state should be able to provide the strongest justification possible for implementing such measures. While a constrained form of consequentialism might provide a justification for such public health interventions, we argue that a stronger justification is provided by a principle of State Enforced Easy Rescue: a state may permissibly compel individuals to engage in activities that entail a small cost to them but a large benefit to others, because individuals have a moral duty of easy rescue to engage in those activities. The principle of State Enforced Easy Rescue gives rise to an Obligation Enforcement Requirement: the state should create the conditions such that submitting to coercive or compulsive measures becomes a fundamental moral duty of individuals, i.e. a duty of easy rescue. When the state can create such conditions, it has the strongest justification possible for implementing coercive or compulsive measures, because individuals have a moral duty to temporarily relinquish the rights that such measures would infringe. Our argument has significant implications for how public health emergencies in the developing world should be tackled. Where isolation and quarantine measures are necessary, states or the international community have a moral obligation to provide certain benefits to those quarantined or isolated. 相似文献
104.
番茄潜叶蛾原产于南美洲的秘鲁,严重危害多种茄科作物,是最具毁灭性的世界检疫性害虫,严重发生地块番茄减产80%~100%。该虫主要借助农产品的贸易活动进行远距离传播扩散。截至2017年,番茄潜叶蛾已在全世界的85个国家和地区发生(以及在22个国家和地区疑似发生)。目前,我国尚没有该虫分布,然而其一旦入侵,将对我国的番茄和马铃薯产业构成巨大威胁。从番茄潜叶蛾寄主范围、危害特点及造成的经济损失、生物生态学习性、地理分布和传播扩散途径、防控措施等方面进行概述,以期为该虫的有效防范提供参考。 相似文献
105.
First record of the quarantine pest Atherigona (Atherigona) oryzae Malloch (Diptera: Muscidae) in Korea 下载免费PDF全文
Occurrence of the invasive quarantine pest fly, Atherigona (Atherigona) oryzae Malloch, is hereby recorded for the first time in Gyeongsangbuk‐do Province, Korea. Morphological characteristics for accurate identification of the species, a list of hosts, and damage patterns are described to provide plant quarantine information for pest management. 相似文献
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107.
Hoover K Uzunovic A Gething B Dale A Leung K Ostiguy N Janowiak JJ 《Journal of nematology》2010,42(2):101-110
To reduce the risks associated with global transport of wood infested with pinewood nematode Bursaphelenchus xylophilus, microwave irradiation was tested at 14 temperatures in replicated wood samples to determine the temperature that would kill 99.9968% of nematodes in a sample of ≥ 100,000 organisms, meeting a level of efficacy of Probit 9. Treatment of these heavily infested wood samples (mean of > 1,000 nematodes/g of sapwood) produced 100% mortality at 56 °C and above, held for 1 min. Because this "brute force" approach to Probit 9 treats individual nematodes as the observational unit regardless of the number of wood samples it takes to treat this number of organisms, we also used a modeling approach. The best fit was to a Probit function, which estimated lethal temperature at 62.2 (95% confidence interval 59.0-70.0) °C. This discrepancy between the observed and predicted temperature to achieve Probit 9 efficacy may have been the result of an inherently limited sample size when predicting the true mean from the total population. The rate of temperature increase in the small wood samples (rise time) did not affect final nematode mortality at 56 °C. In addition, microwave treatment of industrial size, infested wood blocks killed 100% of > 200,000 nematodes at ≥ 56 °C held for 1 min in replicated wood samples. The 3(rd)-stage juvenile (J3) of the nematode, that is resistant to cold temperatures and desiccation, was abundant in our wood samples and did not show any resistance to microwave treatment. Regression analysis of internal wood temperatures as a function of surface temperature produced a regression equation that could be used with a relatively high degree of accuracy to predict internal wood temperatures, under the conditions of this study. These results provide strong evidence of the ability of microwave treatment to successfully eradicate B. xylophilus in infested wood at or above 56 °C held for 1 min. 相似文献
108.
Cooke DE 《Molecular ecology》2007,16(18):3735-3736
Invasive species are, by definition, unwelcome and pathogenic ones, especially so. Tracing the origins and spread of Phytophthora ramorum, the devastating 'Sudden Oak Death' pathogen, in the forests and nurseries of Oregon has revealed differences between forest and nursery pathogen populations that suggest discrete sources of primary inoculum initiate each type of outbreak. New information on the ecology and evolution of this pathogen is presented that helps gauge the effectiveness of quarantine and eradication programmes. 相似文献
109.
Quantitative Risk Assessment of the Pathways by Which West Nile Virus Could Reach Hawaii 总被引:2,自引:2,他引:0
A.?Marm?KilpatrickEmail author Yekaterina?Gluzberg Jeff?Burgett Peter?Daszak 《EcoHealth》2004,1(2):205-209
The introduction of West Nile virus (WNV) to Hawaii could have severe impacts on human health, wildlife health and, as a result, Hawaiis tourism-based economy. To provide guidance for management agencies seeking to prevent the introduction of WNV, we performed a quantitative assessment of the pathways by which WNV could reach Hawaii from North America. We estimated the rate of infectious individuals reaching Hawaii by the following means (1) humans on aircraft, (2) wind-transported mosquitoes, (3) human-transported mosquitoes, (4) human-transported birds or other vertebrates, and (5) migratory birds. We found that pathways 3 and 4 represented the highest risk. We estimated that each year, 7–70 WNV infectious mosquitoes will reach Hawaii by airplane when WNV becomes well established in the Western U.S. Exemptions in current quarantine regulations will also result in the import of birds that will be infectious with WNV for 0.3–2.2 bird-days each year. We propose actions that would substantially reduce the risk of WNV reaching Hawaii by these means, including reinstating aircraft disinsection in cargo holds and altering bird quarantine rules. Finally, research is urgently needed to determine whether a migratory bird can survive the migration from North America to Hawaii with a viremic WNV infection. 相似文献
110.
Abstract: The purpose of this research was to investigate post-harvest heat treatment of Valencia oranges as an effective disinfestation protocol (fast, no fruit damage) for the Mediterranean fruit fly Ceratitis capitata (Wiedemann). Forced high-temperature air was applied under the following conditions: (a) exposure to air temperature of 56°C, for fast increase of temperature in the interior of the fruit, (b) reduction in air temperature to 47°C when the fruit centre reached 47°C and (c) maintenance of fruits in the chamber for another 30 min. Relative humidity in the treatment chamber was kept between 50% and 65% during treatment. Forced air at 47°C applied for 30 min on eggs before hatch or late third instar larvae (the most heat-tolerant stages) resulted in complete kill. Egg and larval sensitivity to high temperature differed between a wild strain and a laboratory genetic-sexing strain based on white pupa mutation. In this strain males emerge from brown pupae and females from white pupae. In particular, mature eggs from the wild strain were significantly more temperature resistant than eggs from the laboratory strain. Exposure of Valencia oranges of a diameter of 7–7.5 cm to 56°C forced air for about 86 and 99 min was required to increase temperature to 47°C at 1.5 cm depth and the fruit centre respectively. Treated oranges showed no substantial peel or interior deterioration, or change in colour and taste when kept at 25°C and 50–60% RH for a period of up to 1 month following treatment. Treatment in 1% O2 atmosphere, produced by flushing of CO2 into the treatment chamber, resulted in about 1°C reduction in killing temperature and faster increase in temperature inside the fruit to a lethal level. 相似文献