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Background  

Rapid diagnosis and surveillance for H5 subtype viruses are critical for the control of H5N1 infection.  相似文献   
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The simultaneous effect of calcium, cobalt, copper and magnesium ions and their interactions on growth and sapogenin steroids accumulation in callus cultures of Agave amaniensis was studied by using a central composite second-order rotatable design. The absence of calcium ions in media increased the sapogenin steroid content, while relatively high concentration of magnesium, cobalt and copper ions simultaneously inhibited the sapogenin steroid formation. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   
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本文报道对杨梅根结线虫病的研究及病原鉴定结果。该病症状为:病树根部形成大小不一的根结,内有乳白色囊状雌虫及棕色卵囊;后期根结腐烂,病树叶片黄化脱落,梢枯乃至死亡。病原鉴定确认,引起该病的根结线虫有3个种:爪哇根结线虫(Meloidogyne javanica)、南方根结线虫(M.incognita)和北方根结线虫(M. hapla)。爪哇根结线虫为优势种。  相似文献   
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Modern teaching trends in medical education exhibit a paradigm shift from the conventional classroom teaching methods adopted in the past to nonconventional teaching aids so as to encourage interactive forms of learning in medical students through active participation and integrative reasoning where the relationship of the teacher and the taught has undergone tremendous transformation. Some of the nonconventional teaching methods adopted at our department are learning through active participation by the students through computer-assisted learning (CD-ROMs), Web-based learning (undergraduate projects), virtual laboratories, seminars, audiovisual aids (video-based demonstrations), and "physioquiz."  相似文献   
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White tail disease (WTD) was found to be a serious problem in hatcheries and nursery ponds of Macrobrachium rosenbergii in India. The causative organisms have been identified as M. rosenbergii nodavirus (MrNV) and its associated extra small virus (XSV). Experimentally transmitted to healthy animals, they caused 100% mortality in post-larvae but failed to cause mortality in adult prawns. The RT-PCR assay revealed the presence of both viruses in moribund post-larvae and in gill tissue, head muscle, stomach, intestine, heart, hemolymph, pleopods, ovaries and tail muscle, but not in eyestalks or the hepatopancreas of experimentally infected adult prawns. The presence of these viruses in ovarian tissue indicates the possibility of vertical transmission. Pleopods have been found to be a suitable organ for detecting these viruses in brooders using the RT-PCR technique.  相似文献   
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Collections of arboreal Psocoptera from the four major national parks of Sumatra and from a range of habitats outside the parks (including many of the predominant perennial crops) are appraised for diversity and species overlap between habitats. The most speciose family (Psocidae, 72 morphospecies) is investigated to determine possible surrogacy values in relation to the more taxonomically intractable Other Psocoptera (17 families, 190 morphospecies), in its incidence in 16 different habitats and four main altitudinal zones. Considerable psocid richness persists in disturbed areas, and the values of protected areas and kebun gardening systems in their conservation are noted.  相似文献   
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