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1.
M P Ivanova V Iu Mel'nikov 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》1988,38(3):427-433
In summation and averaging of sections of the EEG of sensorimotor cortex of both cerebral hemispheres recorded during human static effort of definite duration, a complex of negative-positive oscillations was observed. These oscillations appear before the beginning of the effort, accompany its execution and finishing and are also recorded after cessation of muscles activity. Before the beginning, the potential of readiness is formed. The execution of the effort is accompanied by a slow negative wave which in some people may be broken by a pronounced positivity. Further a "final" potential appears; its fast positive oscillation is formed before the end of the effort, and a slow negative wave in which it turns, appears only after muscles relaxation. 相似文献
2.
34Fusarium graminearum Schw isolates produced 4-deoxynivalenol to form significant amounts of 4, 7 — dideoxynivalenol and lesser amounts of 4 — deoxynivalenol monoacetates on grain substratesin vitro. This is the first report on the capability a large group of naturally occurring isolates to produce 4,7-dideoxynivalenol. The average levels of 4,7-dideoxynivalenol on rice, corn, barley, and wheat as a substrate were respectively 26.8, 14.0, 12.8, and 10.5% of the level of 4-deoxynivalenol. 4, 7 — dideoxynivalenol was present in all examined naturally contaminated wheat kernel samples at levels of 1.7 to 7.9% of the level of 4-deoxynivalenol. These findings suggest that more attention should be given to the occurrence of 4,7-dideoxynivalenol in cereals. 相似文献
3.
Variation in the ribosomal internal transcribed spacers (ITS1 and ITS2) among eight taxa of the Mimulus guttatus species complex 总被引:1,自引:0,他引:1
The internal transcribed spacer region (ITS1 and ITS2) of the 18S-25S
nuclear ribosomal DNA sequence and the intervening 5.8S region were
sequenced from three individuals in each of eight taxa of the Mimulus
guttatus species complex. Three discrete variants, or "types," of ITS
sequences were found, among which 30%-40% of sites differed, compared with
1%-2% within types. Dot plots indicate that these types were not related by
conspicuous rearrangements or inversions. More than one ITS type was often
found in the same taxon, and two of three ITS types span species
boundaries, indicating their presence prior to speciation. These ITS
sequences showed essentially no positional homology with the nearest
sequenced relative, tomato. In contrast, the 5.8S region was relatively
unvaried, with 8 of 162 sites varied in the sample among all eight taxa.
The phylogeny inferred by the most common ITS sequence type, rooted by the
two other ITS types, agreed with isozymes in showing the distinctness of M.
nudatus, M. laciniatus, and M. tilingii from the other five taxa.
相似文献
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Comparative assessment of the properties of a factor inhibiting macrophage migration and interferon]
O F Mel'nikov L D Krivokhatskaia Ia L Povolotski? 《Biulleten' eksperimental'no? biologii i meditsiny》1977,83(3):302-303
The authors investigated some functional properties of interferon and the macrophages migration inhibitory factor (MIF) obtained by stimulation of human tonsil lymphocytes with the virus of Newcastle disease (NDV) or O-streptolysin. Both the interferon and MIF inhibited actively the migration of human tonsil cells, but differed by the anti-viral activity, and sensitivity to heating at 56 degrees C for 30 min. Stimulation of human tonsil lymphocytes with NDV leads to production of a more wide range of delayed hypersensitivity mediators than stimulation with O-streptolysin. 相似文献
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8.
Electron-microscopic and electron-cytochemical method were used to indicate the capability of Pseudomonas mallei (str. N 10230) to produce extracellular slime during the agent growth on the meat-peptone agar. In case of guinea pigs infection the agent forms a capsule that defends the pathogen from phagocytosis. 相似文献
9.
报道了小菇科小菇属真菌10个中国新记录种,香菌组:橙盖小菇Mycena aurantiidisca、黄白小菇Mycena flavoalba、粉黄小菇Mycena floridula;棘刺组:异刺小菇Mycena heteracantha;纤柄组:碱味小菇Mycena amygdalina;脆足组:粉被小菇Mycena zephirus;冬生组:绣线菊小菇Mycena speirea、冬生小菇Mycena hiemalis;小菇组:绒柄小菇Mycena flos-nivium,分别来自吉林等11个省份、自治区。提供了每个物种的形态描述和线条图,以及与相近种的讨论。共计90条自测及下载ITS序列,在采用贝叶斯法和最大似然法构建的小菇属系统发育树中,新记录种均得到分子数据支持。凭证标本存放于吉林农业大学菌物标本馆(HMJAU)。 相似文献