排序方式: 共有17条查询结果,搜索用时 15 毫秒
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裂缝常革螨形态描述(蜱螨亚纲:革螨股:寄螨科) 总被引:3,自引:0,他引:3
裂缝常革螨 Vulgarogamasus lyriformis ( Mc Grow et Farrier,1 96 9)分布于美国、加拿大和前苏联。 2 0 0 0年自朝鲜入境货物中采得该螨。在所查到的文献中 ,仅《ОпределительОбитающихвПочвеКлещеи,М esostigmata》一书有该种的记载 ,但只记载有雌螨胸板、生殖区、头盖和雄螨足 的特征 ,无完整描述。今根据朝鲜标本 ,详细描述其雌螨、雄螨、前若螨和幼螨。文中测量单位为μm,括号内为测量均值。裂缝常革螨 Vulgarogamasuslyriformis (Mc Grow et Farrier,1969)图 1- 6 裂缝常革螨 Vulgarogamasu… 相似文献
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首次在光学显微镜下详细观察比较了实蕨科(Bolbitidaceae)的实蕨(Bolbitis hainanensis Ching et C.H.)和刺蕨[Egenolfia appendiculata (Willd.) J.Sm.]的配子体连续的发育过程.实蕨和刺蕨孢子均为单裂缝,播种5 d 后孢子萌发,萌发类型为书带蕨型(Vittaria-type),播种30~35 d 后发育为片状体.幼原叶体不对称,成熟原叶体具毛状体,呈心形.播种 55 d 后开始有性器出现.通过重点比较丝状体、原叶体、假根及性器等方面的异同,讨论了Holttum和秦仁昌对该科的系统划分,并且进一步支持了秦仁昌的观点. 相似文献
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模拟稻田土壤在加入不同量的 (NH4)2SO4和双氢按(DCD)抑制剂的溶液后先进行淹水培养,然后让土壤自然蒸发变干,直至土壤产生裂缝到裂缝稳定,最后在裂缝稳定后的复水的连续培养试验。通过模拟对土壤进行复杂的、动态的水分含量变化过程中试验,探讨双氢胺抑制剂对其N2O释放的影响。每天监测土体释放的N2O通量,以及渗漏液中溶解的N2O浓度和pH值。这些监测结果表明:在相同的水分管理条件下,土壤中没有氮肥加入,只有DCD加入的A处理释放N2O气体最少,其平均释放通量为340.91 μg m-2 h-1; 土壤中有高剂量的氮肥和DCD加入的E处理释放N2O最多,其平均释放通量为9280.23 μg m-2 h-1。裂缝产生稳定后的复水能减少N2O向空气中的释放。渗漏液中的N2O浓度都是过饱和的。当土壤中肥料(NH4)2SO4加入量(每千克土壤中外加N≤3g)相对较少的情况下,DCD抑制剂能抑制裂缝产生过程中的N2O释放;当土壤中肥料(NH4)2SO4加入量(每千克土壤中外加N≥6g)相对较多的情况下,DCD抑制裂缝产生过程中的N2O释放效果不明显。此外还得出(NH4)2SO4和DCD的加入量比是10:1 时,其抑制N2O排放的效果比(NH4)2SO4和DCD的加入量比分别是10∶1.5和10∶2要好。土体释放的N2O通量和渗漏液中溶解的N2O浓度之间不存在相关性,土体释放的N2O通量和渗漏液中的pH值之间也不存在相关性。但是渗漏液中的N2O浓度和pH值之间存在显著的正线性相关关系。 相似文献
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Jiang Qiu Hong Li QingLin Zhang LiHui Huang YaQiao Guo Shen Tu Ting Wang DongTao Wei 《中国科学:生命科学英文版》2009,52(7):683-690
Event-related brain potentials (ERPs) were measured when 24 Chinese subjects performed the earthquake color-matching Stroop
task. All of them have experienced the great Sichuan earthquake (5.12), with 12 subjects in each of Chengdu city and Chongqing
city (different earthquake experiences) groups. The behavioral data showed that the earthquake Stroop task yielded robust
the earthquake interference effect as indexed by longer RT for earthquake-related (Related) words than earthquake-unrelated
(Unrelated) words only in the Chengdu group. Scalp ERP analysis also revealed the neurophysiological substrate of the interference
effect: a greater positivity (P350–450) in Related words as compared to Unrelated words was found between 350 and 450 ms post-stimulus
over fronto-central scalp regions in the Chengdu group, while the interference effect was not found in the Chongqing group.
The P350–450 might reflect an earthquake experience interference, but also attention enhancing, effect of earthquake-related
words. Dipole source analysis of the difference wave (Related-Unrelated) showed that a generator was localized in the parahippocampal
gyrus, which was possibly associated with flashbulb memory (personal earthquake experience). The results indicated that different
personal earthquake experiences might be critical in engaging the neural mechanisms that underlie the modulation of selective
attention.
Supported by the National Natural Science Foundation of China (Grant No. 30800293), the Key Project of Philosophy and Social
Science of Chinese Ministry of Education (Grant No. 08JZD0026), and the Southwest University Doctoral Fund. 相似文献
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类甜蛋白的结构特征以及功能研究进展 总被引:2,自引:1,他引:2
类甜蛋白是一种具有多种生物学活性及重要功能的植物防御蛋白,属于病程相关蛋白。近年来关于类甜蛋白具有抗真菌活性的研究较多。类甜蛋白具有葡聚糖酶活性,能结合并降解真菌细胞壁的组成成分—β-1,3葡聚糖酶。在三维晶体结构中类甜蛋白表面的一个酸性“V”字形裂缝对其抗真菌活性起着至关重要的作用。对类甜蛋白结构与功能的关系,不同植物中类甜蛋白的生物学特性,以及国内外基因工程中类甜蛋白基因的应用研究进展进行了综述。 相似文献
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