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91.
异环足摇蚊属隶属于双翅目摇蚊科直突摇蚊亚科,全世界已记录4种。本文对中国产本属进行了系统研究。记述了2新种:简异环足摇蚊A.simplex sp.nov.和扎陵异环足摇蚊A.zhalingensis sp.nov.,重新核定了亮异环足摇蚊A.lucens(Zett.)。提供了世界本属雄成虫检索表。依据中国标本和相关文献,对Cranston等1989年所描述的本属的触角比、前足比、下附器的形状等属级鉴别特征予以订正。模式标本均保存于南开大学生物系。简异环足摇蚊A.simplexsp.nov.:正模:雄性,西藏建日,9/3/1987,邓成玉采。与本属已知种的区别:后足胫节无栉;无额鬃和唇基毛; R2+3脉清晰。扎陵异环足摇蚊A.zhalingensis sp.nov.:正模:雄性,青海扎陵湖,8/20/1986,任淑智采。与本属已知种的区别:个体大;无唇基毛;翅臀叶强烈突出,半球状;下附器三角形,强烈骨化,抱器端节具有13根粗长的刚毛。 相似文献
92.
几种数量综述方法的介绍与比较 总被引:3,自引:0,他引:3
综述是科学研究中的一种重要方法,数量综述较传统的叙述性综述有许多优多,文章介绍并比较了目前在科学研究中比较流行的几数量综述方法. 相似文献
93.
西藏南部放射虫微体古生物研究进展 总被引:6,自引:0,他引:6
西藏南部的雅鲁藏布蛇绿岩带以及该带之南的沉积地层带(特提期沉积区,北喜马拉雅亚区)中广泛发育着大量含放射虫地层,放射虫研究在确定该区蛇绿岩的形成时代,解释造山带复杂的地层层序以及揭示印度板块与欧亚板块在古近纪碰撞老祖宗前的古海洋盆地的演化历史等方面发挥了重要作用。根据已发表的文献以及我们正在进行中的初步成果显示,藏南地区的含放射虫地层的时代分布之中三叠世(安尼期)至晚白垩(土仑期)。这些地层的岩性包括硅质岩,硅质泥岩,凝灰质细碎屑岩和泥晶灰岩等,尽管藏南的放射虫研究已取得一些成果,但系统的放射虫研究与地层研究仍然有待于进一步深入开展。 相似文献
94.
Oplopanone类倍半萜的研究进展 总被引:2,自引:0,他引:2
本文综述了Oplopanone类倍半萜化合物的结构、来源分布、波谱特征、生物合成途径以及人工合成等方面的研究概况,并且对文献中报道的三个该类型化合物碳谱中的部分碳信号进行了重新归属. 相似文献
95.
Cheilostomatous Bryozoa from Vanuatu 总被引:1,自引:0,他引:1
KEVIN J. TILBROOK FLS P. J. HAYWARD FLS D. P. GORDON FLS 《Zoological Journal of the Linnean Society》2001,131(1):35-109
The present account of some Bryozoa from Vanuatu is the first study of reef-flat species from the eastern Coral Sea. Based on samples collected from several shallow water localities on the island of Efate, a total of 92 species is described, including a new family, three new genera and 20 new species. Some of the newly recognized species are the result of taxonomic revision stimulated by these new samples, while others are entirely new to science. Of the new taxa described here, 16 are presently known only from Vanuatu. The total number of species recorded does not accurately represent the true taxonomic diversity of the Cheilostomatida of Vanuatu, and further sampling, at other localities and in other habitats, is needed before it can be reasonably estimated. The fauna is predominantly Indo-West Pacific in character with a high proportion of species apparently known only in the Southwest Pacific. 相似文献
96.
V. Raghavan 《The New phytologist》2003,159(3):565-583
97.
This article reviews the psychophysiological and brain imaging literature on emotional brain function from a methodological point of view. The difficulties in defining, operationalising and measuring emotional activation and, in particular, aversive learning will be considered. Emotion is a response of the organism during an episode of major significance and involves physiological activation, motivational, perceptual, evaluative and learning processes, motor expression, action tendencies and monitoring/subjective feelings. Despite the advances in assessing the physiological correlates of emotional perception and learning processes, a critical appraisal shows that functional neuroimaging approaches encounter methodological difficulties regarding measurement precision (e.g., response scaling and reproducibility) and validity (e.g., response specificity, generalisation to other paradigms, subjects or settings). Since emotional processes are not only the result of localised but also of widely distributed activation, a more representative model of assessment is needed that systematically relates the hierarchy of high- and low-level emotion constructs with the corresponding patterns of activity and functional connectivity of the brain. 相似文献
98.
Herbivory-induced signalling in plants: perception and action 总被引:1,自引:0,他引:1
Plants and herbivores have been interacting for millions of years. Over time, plants have evolved mechanisms to defend against herbivore attacks. Herbivore-challenged plants reconfigure their metabolism to produce compounds that are toxic, repellant or anti-digestive for the herbivores. Some compounds are volatile signals that attract the predators of herbivores. All these responses are tightly regulated by a signalling network triggered by the plant's perception machinery. Several compounds that specifically elicit herbivory-induced responses in plants have been isolated from herbivore oral secretions and oviposition fluids. Elicitor perception is rapidly followed by cell membrane depolarization, calcium influx and mitogen-activated protein kinase (MAPK) activation; plants also elevate the concentrations of reactive oxygen and nitrogen species, and modulate phytohormone levels accordingly. In addition to these reactions in the herbivore-attacked regions of a leaf, defence responses are also mounted in unattacked parts of the attacked leaf and as well in unattacked leaves. In this review, we summarize recent progress in understanding how plants recognize herbivory, the involvement of several important signalling pathways that mediate the responses to herbivore attack and the signals that transduce local into systemic responses. 相似文献
99.
East Asian species of the genera Hybrizon and Ghilaromma are reviewed. Four species of Hybrizon, H. buccatus (Brébisson 1825), H. ghilarovi Tobias, 1988, H. juncoi (Ceballos 1957) and H. flavofacialis Tobias, 1988 and two species of Ghilaromma, G. orientalis Tobias, 1988 and G. ussuriensis Tobias, 1988, were recognized. H. ghilarovi was recorded from Korea, Japan and China, while H. juncoi was recorded from Korea, for the first time. The specimens recorded from Japan as G. fuliginosi (Wilkinson, 1930) by Watanabe (1984) are referred to G. orientalis herein. This species is newly recorded from Korea and Japan. Keys to East Asian species of Hybrizon and the world species of Ghilaromma are also provided. 相似文献
100.
This article summarizes some of the data that have been accumulated on several growth factors. Biochemical and biological properties of the Epidermal, Fibroblast, Astrocytes and Tumor growth factors (EGF, FGF, AGF, TGF) and those of growth factors derived from Platelets (PDGF), Brain (BDGF, ECGF), Eye (EDGF) and Cartilage (CDGF) are reviewed, as well as the in vitro mechanism of action of EGF and PDGF. The in vivo effects of these growth factors, particularly the experiments achieved to understand the physiological or physiopathological significance are described. The potential interest of these molecules in pharmacology and their use as wound healing agents is discussed. 相似文献