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排序方式: 共有492条查询结果,搜索用时 15 毫秒
81.
Koiwai M Hamaoka T Haritani M Shimizu S Zeniya Y Eto M Yokoyama R Tsutsui T Kimura K Yamane I 《Veterinary parasitology》2006,135(2):175-179
Serum samples from 2420 clinically healthy dairy cattle, randomly selected from stored sera in 18 districts of Japan, were tested for the presence of Neospora caninum antibodies using an indirect fluorescent antibody test (titer > or =1:200). Nationwide seroprevalence is estimated at 5.7% (139/2420). Seropositive cattle were detected in all surveyed districts despite the evidence of confirmed case reports of bovine neosporosis, showing that N. caninum is widely distributed throughout Japan. Age-specific seroprevalence did not increase with cattle age, suggesting that Neospora infection is likely to be transmitted vertically rather than horizontally in Japan. Considering that N. caninum seropositive cows are thought to be more likely to abort, substantial fetal losses may be induced by N. caninum infection in Japan. Devising strategies are needed to reduce the economic impact on the Japanese dairy industry. This is the first study to investigate the nationwide seroprevalence of N. caninum in cattle in Asia. 相似文献
82.
日本木结构的发展历程与现状 总被引:1,自引:0,他引:1
日本是一个地震、台风多发国家,其木结构的发展虽非一帆风顺,但得到了举世嘱目的发展.日本木结构建筑文化和技术曾被誉为世界之冠.了解日本木结构的发展与成功经验,对促进我国木结构健康、稳步的发展具有重要的作用.本文介绍了日本木结构的发展历程及现状. 相似文献
83.
The paper presents an analysis of the economic relationship between the two most important economies in Asia. Over the last decades, the Chinese and Japanese economies have become more economically interdependent, a development which will, in the long run, impact the countries' political relationship. The paper seeks to answer the question: How can China and Japan gain from the current economic situation, further enhance their relationship and increase their synergies for regional economic development? Data on trade and Foreign Direct Investment are used in combination with primary data from interviews with Japanese and Chinese companies on how they perceive the current business situation and future potential. The result of the data analysis shows that the countries have much to gain from their economic interdependence. The firms see great potential in their respective markets but are concerned about political turbulence. Three possible scenarios for the future economic relationship are presented, including fierce competition on all markets and a leveraging of resources for mutual development between Chinese and Japanese companies. 相似文献
84.
日本大麦种质资源鉴定评价 总被引:2,自引:0,他引:2
为了解日本大麦特性, 从生育期、株高、穗长、穗粒数和千粒质量等方面对引自日本的271份大麦种质进行了鉴定与评价.结果表明,日本大麦生育期分布较宽,抽穗期和成熟期差异较大;相对于对照,株高普遍偏高;穗长表现为二棱材料穗长均长于对照,四棱材料中有44.9%的穗长分布在8.0~9.9 cm之间.六棱除了5份与西引2号的穗长相等外,其余均比对照长.穗粒数的表现,二棱少于四棱,四棱少于六棱.研究的38份二棱材料中有20份的穗粒数与对照相当;四棱材料粒数类型多样,但绝大多数为特多粒型.14份六棱材料中有11份与西引2号类型一样,属于特多粒型;千粒质量的表现为二棱大于四棱,四棱大于六棱.38份二棱材料中仅有7份千粒质量小于西安91-2,6份与西安91-2属于同一类型.四棱材料大部分为中小粒类型.六棱材料中仅二份与对照属于特小粒类型,其余12份粒质量均大于对照西引2号. 相似文献
85.
日本水稻机械化的现状及展望 总被引:1,自引:0,他引:1
概括了日本稻作生产、大米加工.消费的现状以及日本政府的农业政策。介绍了日本稻作技术的要点、稻作机械化的现状与特征。从超省力.减轻劳力、低成本化、稻米高附加价值化、节能.减轻环境负荷等视点展望了下一代的稻作机械化技术。 相似文献
86.
87.
日本和美国社区支持型农业的发展及其启示 总被引:7,自引:1,他引:6
社区支持型农业(CSA)是可持续农业的重要形式之一,近几年在国内逐渐受到人们关注,为借鉴日本和美国CSA发展的经验教训,促进中国CSA健康发展和城乡互补。为此,重点介绍了CSA在两国的发展历程及趋势,分析了兴衰背后的社会原因及其启示,并探讨了中国发展社区支持农业的潜在需求。研究得出:CSA最早产生的日本,随着有机农场的减少,以及社会经济变化等原因,CSA已经变得日益衰落;而在其后CSA兴起的美国却迎合了广大民众的需求得以蓬勃发展,并且功能形式日趋灵活多样,农场平均规模趋于减小。CSA的兴起和发展与其社会背景紧密相关,CSA多数提倡采用机生产方式同时兼备多种功能,其发展遵循平等互利、规模适度等原则,外部支援和参与有助于增强其发展活力。这对中国CSA和持续农业发展具有借鉴意义。该文从维护农民利益、保障市民需求及城乡一体化等角度,认为CSA是中国发展可持续农业、实现城乡协调发展的一条“绿色通道”。 相似文献
88.
<Emphasis Type="Italic">Turnip yellow mosaic virus</Emphasis> isolated from Chinese cabbage in Japan
Namiko Kirino Koji Inoue Koji Tanina Yuya Yamazaki Satoshi T. Ohki 《Journal of General Plant Pathology》2008,74(4):331-334
A virus that caused a distinct yellow mosaic was isolated in Okayama, Japan from Chinese cabbage (Brassica rapa L., Pekinensis group). The virus, with spherical particles ca. 28 nm in diameter, was mechanically transmissible only to
cruciferous species. From the host range, characteristic morphology of virus particles, serology and sequence analysis of
coat protein gene, the causal virus was identified as Turnip yellow mosaic virus (TYMV). Seed transmission of TYMV at 0–2.2% in Chinese cabbage was confirmed. This report is the first of TYMV from Chinese
cabbage and in Japan.
The nucleotide sequence data reported are available in the DDBJ/EMBL/GenBank databases as accessions AB358971 and AB358972. 相似文献
89.
90.
Effects of climate on temporal variation in the abundance and distribution of the demersal fish assemblage in the Tsushima Warm Current region of the Japan Sea
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In the present study, we examined the effects of climate on temporal variation in the abundance and geographical distribution of demersal fishes at both interannual and decadal scales in the Tsushima Warm Current region of the Japan Sea using single‐trawler fishery data (1972–2002). This single‐trawler fishery targeted multiple species with different geographical affinities and life history traits. Thus, these data were suitable for examining the biological mechanisms that underlie how species respond to climate variability. Our results indicate that the distributional changes of species in response to decadal climate variability are best explained by asymptotic length, which indicates that warming has greater negative effects on larger fishes in the Japan Sea. However, none of the variables examined (including geographical affinity, asymptotic length and age at maturation) could explain the shift in abundance at interannual or decadal scales. It should be noted that life history traits and geographical affinities only provide partial explanations of the responses of species to environmental variability, thereby suggesting that other factors, such as interactions among species, may be involved in mediating species responses. 相似文献