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181.
Visfatin is a newly discovered visceral fat-specific adipocytokine. It is upregulated in obesity and exerts insulin-mimetic effects in various tissues in human and mouse. We reported here the cloning and characterization of porcine visfatin, its three alternate splicing variants. Sequence analysis indicated that variant 1 is the predominant form among species, which contains an open reading frame of 1473 bp encoding a 52-kDa protein of 491 amino acids. While the other two variants were predicted to encode two 3' truncated proteins due to early termination. The nucleotide and amino acid sequences deduced from variant 1 were conservative across species. The porcine visfatin gene was composed of 11 exons at least and had exactly the same exon/intron structure as the human orthologs. Nested PCR showed that variants 1 and 3 were ubiquitously expressed in porcine tissues and that variant 2 was expressed in most tissues examined with exception of testis and liver. The discovery of the three variants of visfatin in porcine would be useful to the further investigation of the function of the visfatin gene.  相似文献   
182.
近10年来, 随着人们对环境的关注, 绿色发展成为农业生产的主流。在土传病害的防治中, 要尽可能减少对环境和生态的影响, 同时保证取得更好的经济效益。因而, 一些环境友好的防治技术受到重视。农业防治技术如抗性品种利用和嫁接、阻截传播、深翻、轮作和无土栽培; 生物防治技术如生物熏蒸、厌氧消毒、生物防治制剂等; 物理防治技术如太阳能消毒、火焰消毒、微波消毒、电消毒、射频消毒也在不断地创新; 化学防治技术主要依赖土壤熏蒸剂, 一些新型的环境友好的熏蒸剂如异硫氰酸烯丙酯、二甲基二硫、乙二腈、乙蒜素等也在不断发展。熏蒸剂新剂型、新的施药机械也在不断创新。土壤熏蒸剂在防治土传病害时, 也会对土壤中的微生态造成不同程度的影响。此外, 我们也应该清醒地认识到任何技术都有两面性, 并正视不同防治技术中的不足。土传病害作为一类难以防治的病害, 也面临着巨大的挑战, 高传染性要求有高质量的种苗和高效的防治和阻隔技术, 土传病害的定量检测技术, 土壤中的病原菌数量与发病的关系、土壤微生态对发病的影响都是亟待研究和解决的问题。在防控土传病害时, 如何减少温室气体的排放、减少防治投入以及塑料薄膜的污染均为面临的环境和经济学挑战。  相似文献   
183.
白蜡吉丁肿腿蜂Sclerodermus pupariae和松褐天牛肿腿蜂S.alternatusi是天牛和吉丁类害虫的重要天敌?本试验以意大利蜜蜂Apis mellifera蛹为替代寄主, 研究了两种肿腿蜂寄生意大利蜜蜂蛹时其子代的发育过程和数量?结果表明, 利用意大利蜜蜂蛹能成功繁育白蜡吉丁肿腿蜂和松褐天牛肿腿蜂?白蜡吉丁肿腿蜂对蛹的寄生率和羽化出蜂的寄主比例与松褐天牛肿腿蜂无显著差异?以意大利蜜蜂蛹为寄主时, 两种肿腿蜂的产卵前期?卵期?幼虫期?蛹期和卵-成蜂发育历期均无显著差异?单头肿腿蜂雌蜂寄生1头蛹时, 松褐天牛肿腿蜂的子代雌蜂数(17.61头/窝)和子代总数(18.83头/窝)均显著低于白蜡吉丁肿腿蜂的子代雌蜂数(25.10头/窝)和子代总数(26.52头/窝)?两种肿腿蜂的子代性比均具有显著的偏雌特征, 松褐天牛肿腿蜂和白蜡吉丁肿腿蜂子代雄性比分别为6.83%和6.35%, 其子代雄蜂数和雄性比例均无显著差异?综上所述, 意大利蜜蜂蛹可作为白蜡吉丁肿腿蜂和松褐天牛肿腿蜂人工繁育的替代寄主, 这为两种肿腿蜂的规模化繁育提供了参考?  相似文献   
184.
The objective of this special issue is to highlight the current state of research in the field of insects as food and feed, but also other aspects on the exploitation of insect farming. In this editorial, we make a short introduction of the topic of the special issue, briefly present the contributions that are collected in it and offer some thoughts on the future research priorities and challenges that should be addressed. Regarding insect farming, there are additional applications, such as fertilizer, health-promoting products, and cosmetics, that can be produced and utilized, that go far beyond food and feed production.  相似文献   
185.
186.
Biofertilizers instead of synthetic chemicals are known to improve plant growth through the supply of plant nutrients and they may help sustaining environmental health and soil productivity. An experiment was carried out to evaluate fruit yield and macronutrient foliar contents of yellow passion fruit plants (Passiflora edulis) as a function of biofertilizers and nitrogen-phosphorus-potassium (N-P-K) fertilizing in Brazil (2005–2007). The experimental design was randomized in blocks with treatments, which were distributed in a factorial arrangement (3 × 2) referring to biofertilizer application [without biofertilizer, simple biofertilizer and enriched biofertilizer] and mineral fertilizing with NPK (fertilized and non-fertilized), with three replications of nine plants. Nutritional status of yellow passion fruit is affected by biofertilizer. Simple biofertilizer promotes optimum supplies of phosphorus, calcium and sulfur, while enriched biofertilizer promotes optimum supplies of phosphorus, potassium, calcium and sulfur. Both biofertilizers stimulated fruit yield, with results above Brazilian average.  相似文献   
187.
Potassium uptake efficiency of safflower and sunflower was studied under semi-controlled conditions in loamy and sandy soils. Both species performed better in loamy soil. Safflower had higher agronomic efficiency and higher relative root length under suboptimal K supply. Safflower had higher specific root density and less root radius at all K levels. Safflower had higher relative root-shoot ratio under suboptimal K in loamy soil. Both species had similar K-influx at low and optimal K in loamy soil, while sunflower had higher influx under suboptimal and optimal supplies in sandy soil. Safflower had higher shoot demand in both soils under suboptimal and optimal K. Both species depleted similar amounts of soil solution-K under suboptimal K in sandy soil, while sunflower was more efficient under suboptimal levels in loamy soils. Sunflower depleted more extractable-K under both suboptimal and optimal K. Safflower could be considered K-uptake efficient crop.  相似文献   
188.
Field experiments were conducted in 2011 and repeated in 2012 to study the nematicidal potentials of acacia, brassica, neem, and seaweed as alternatives to chemical nematicide on population management of Heterodera glycines and growth and yield of soybean. Results obtained showed acacia at 200 g, neem at 450 g, brassica at 1000 g, and seaweed at 2000 g caused the maximum suppression of population of H. glycines and produced the highest yield and growth of soybean. Neem, brassica, acacia, and seaweed caused reduction in H. glycines population by 48.3%, 41.4%, 34.5%, and 28.3%, respectively. Also, neem, brassica, acacia, and seaweed produced increase in soybean pods number by 58.7%, 33.7%, 28%, and seaweed 37.9%, respectively. The results obtained showed the potentialities of these plant materials as alternative to synthetic chemical pesticides. The plant could be utilized in a sustainable farming system to save the environment, conserve the biodiversity, and protect man against harmful effects of chemical nematicides.  相似文献   
189.
There have been few attempts to identify the way different perspectives of corruption are employed in Papua New Guinea (PNG). The paucity of such analysis makes it difficult to identify the way scholars and policy‐makers understand corruption in the country, in turn leading to potentially poor targeting of anti‐corruption programmes. This article categorises perspectives of corruption that are found in academic and policy accounts of PNG. It finds that this literature is marked by an over‐reliance on ‘mainstream’ Western interpretations of the definition, causes and solutions to corruption. In turn, it is argued that there is an important role that ‘critical’ and culturally aware academics can play in reframing debates about corruption in PNG and the Pacific.  相似文献   
190.
为探讨控制性分根区交替灌溉条件下不同水氮供给对作物生长特性的影响,采用番茄盆栽试验,研究了交替灌溉和水氮处理对番茄生长、产量和水分利用的影响.结果表明:交替灌溉方式下,低氮处理的番茄株高较大;高水低氮和低水中氮处理的茎粗较大;中氮处理的干物质累积总量分别是高氮和低氮的1.25倍和1.01倍.交替灌溉高水处理的水分利用效率均值分别是交替灌溉低水处理和常规充分灌水处理的1.05倍和1.12倍.交替灌溉增加根冠比7.89%~ 31.61%.常规充分灌水处理的产量均值最大,分别是交替高水和交替低水的1.05倍和1.39倍.在交替灌水条件下,中氮处理的耗水量分别是低氮和高氮的1.04倍和1.16倍.  相似文献   
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