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排序方式: 共有145条查询结果,搜索用时 15 毫秒
41.
研究了5种市售粮食的粉尘爆炸,并利用录相对它们的点火过程进行了初步定量分析,得到点火持续时间和点火初期火焰扩展速度;观察到过100目筛的粮食细粉尘悬浮在空中时,在合适的条件下,遇火柴头大小的能源,极易引起快速燃烧,导致粉尘爆炸。 相似文献
42.
Tímea Szederjesi Tomáš Pavlíček Orsolya Márton Virág Krízsik Csaba Csuzdi 《Journal of Natural History》2019,53(5-6):301-314
Dendrobaena veneta is one of the most widely used compost worms now distributed all over Europe and has been described under several synonymous names. Besides the typical stripy red specimens, another form bearing pinkish pigmentation also exists, mostly found in natural habitats in the East Mediterranean. Here we provide the first integrative taxonomic analysis of D. veneta, including some closely related species. Both the morphological and molecular results highly support the resurrection of D. succinta, a former synonym of D. veneta. In addition, we describe a peculiar new species, D. karacadagi sp. n. from Anatolia, and prove the highly homoplasious character of the cross section of the longitudinal musculature.
urn:lsid:zoobank.org:pub:336D3F7A-AEA1-465B-9096-03070C761A6A 相似文献
43.
吴守荣 《山东科技大学学报(自然科学版)》1999,(2)
本文从影响锚喷工程观感质量的因素出发,运用模糊数学知识,结合工程实例,建立了锚喷工程观感质量模糊评价模型。 相似文献
44.
合成了两个含有喹吖啶单元的三价钴配合物,并用元素分析、核磁和质谱作了表征,用吸收光谱、荧 光光谱、圆二色谱和黏度法等手段研究了上述配合物与小牛胸腺DNA的相互作用.实验结果表明,所合成的配 合物很可能以典型的插入模式与DNA相结合. 相似文献
45.
The spindle assembly checkpoint guards against chromosomal missegregation but does not induce arrest in oocytes that contain a few achiasmatic chromosomes (univalents). We followed the fate of univalents in oocytes during the first meiotic division, and although these preserved a meiotic kinetochore structure, they were also bi-oriented in a mitotic manner. The hybrid chromosomal configuration attained by univalents allows them to evade the spindle assembly checkpoint and contribute to aneuploidy in oocytes. 相似文献
46.
S. K. Steinsvåg 《Cellular and molecular life sciences : CMLS》1986,42(7):798-803
Summary Fetal rat brain fragments grown in nonadherent stationary organ culture for 50 days have been investigated ultrastructurally. Synaptogenesis and myelin formation occurred at the same time as the corresponding time-dependent events in the developing brain in vivo. Intermediate junctions were observed between cellular processes lining a central cavity in the fragments and later associated with astrocytes at the surface. Gap junctions and tight junctions were also present. In some fragments cilia were observed in the central cavity. Subependymal basement membrane labyrinths were observed in all fragments after 10 days in culture. The ultrastructural characteristics and the tissue-like structure in general were preserved for at least 50 days in this tissue culture system. The brain fragments may therefore be a valuable supplement to existing culture methods for nervous tissue.Research fellow from the Norwegian Research Council for Sciences and Humanities. This work was supported by the Norwegian Cancer Society. 相似文献
47.
Genomic sequence of the pathogenic and allergenic filamentous fungus Aspergillus fumigatus 总被引:1,自引:0,他引:1
Nierman WC Pain A Anderson MJ Wortman JR Kim HS Arroyo J Berriman M Abe K Archer DB Bermejo C Bennett J Bowyer P Chen D Collins M Coulsen R Davies R Dyer PS Farman M Fedorova N Fedorova N Feldblyum TV Fischer R Fosker N Fraser A García JL García MJ Goble A Goldman GH Gomi K Griffith-Jones S Gwilliam R Haas B Haas H Harris D Horiuchi H Huang J Humphray S Jiménez J Keller N Khouri H Kitamoto K Kobayashi T Konzack S Kulkarni R Kumagai T Lafon A Lafton A Latgé JP Li W Lord A Lu C Majoros WH May GS 《Nature》2005,438(7071):1151-1156
Aspergillus fumigatus is exceptional among microorganisms in being both a primary and opportunistic pathogen as well as a major allergen. Its conidia production is prolific, and so human respiratory tract exposure is almost constant. A. fumigatus is isolated from human habitats and vegetable compost heaps. In immunocompromised individuals, the incidence of invasive infection can be as high as 50% and the mortality rate is often about 50% (ref. 2). The interaction of A. fumigatus and other airborne fungi with the immune system is increasingly linked to severe asthma and sinusitis. Although the burden of invasive disease caused by A. fumigatus is substantial, the basic biology of the organism is mostly obscure. Here we show the complete 29.4-megabase genome sequence of the clinical isolate Af293, which consists of eight chromosomes containing 9,926 predicted genes. Microarray analysis revealed temperature-dependent expression of distinct sets of genes, as well as 700 A. fumigatus genes not present or significantly diverged in the closely related sexual species Neosartorya fischeri, many of which may have roles in the pathogenicity phenotype. The Af293 genome sequence provides an unparalleled resource for the future understanding of this remarkable fungus. 相似文献
48.
In work undertaken in both Malta and Lebanon we have been reflecting on the current means by which the international community
apply concepts intended to achieve what is called “sustainable development.” In an attempt to make means and ends conform
to each other we have developed a holistic approach to what is essentially a timeless need for understanding, systemic planning,
and compassionate stewardship. This essay indicates that we may be closer to holistic means with which to realize these goals
than we know. It describes how some planning and analysis methods have their origins in ancient traditions. However, the milieu
in which sustainability occurs is often unsympathetic to and sometimes incompatible with the ideals of holism. The essay assesses
the current understanding of sustainability and points to the need for a wider and more inclusive base to contemporary sustainability
as practiced in the community. 相似文献
49.
M. Koltay B. Radnai Zs. Bános I. Szeri P. Anderlik I. Virág 《Cellular and molecular life sciences : CMLS》1969,25(10):1081-1083
Résumé Comme conséquence de l'interaction de la maladie homologue produite dans des souris F1 hybrides adultes et de l'infection avec le virus de la chorioméningite lymphocytique, les signes histologiques de la maladie homologue étaient aggravés. D'autre part, une action protectrice inversement proportionnelle à la gravité des altérations histologiques attribuables à la maladie homologue vis-à-vis des manifestations neurologiques de l'infection avec ce virus était évidente. 相似文献
50.