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1.
记述中国产突颜寄蝇亚科1新纪录属:亚美寄蝇属Subclytia Pandellé,1894及1新纪录种,圆腹亚美寄蝇S.rotundiventris(Fallén,1820)。标本保存于沈阳师范大学昆虫标本馆(SYNU)。  相似文献   

2.
记述掘甲族Lachnogyini中国l新纪录属掘甲属Lachnogya Ménétriés,1849,及中国1新纪录种鳞掘甲Lachnogya squamosa Ménétriés,1849.提供了掘甲属Lachnogya种检索表,以及鳞掘甲Lachnogya squamosa Ménétriés,1849形态描述、分布及形态特征图.研究标本保存在河北大学博物馆.  相似文献   

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记述了齿蓟马属Odontothrips Amyot & Serville(Thysanoptera:Thripidae)两个中国新纪录种,即间齿蓟马O.intermedius(Uzel)和蒙古齿蓟马O.mongolicus Pelikón,并首次描述了两种雄性外生殖器结构。提供了新纪录种的形态描述、特征图及该属中国已知种类分种检索表。研究标本保存于中国科学院动物研究所国家动物博物馆。  相似文献   

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中国蚜科一新纪录属四新纪录种(同翅目,蚜总科)   总被引:1,自引:1,他引:0  
研究了中国蚜科Aphididae 1新纪录属4新纪录种,包括蚜亚科Aphidinae蚜属Aphis 2新纪录种:番樱桃蚜Aphis eugeniae van der Goot,1917和粉蚜居梨亚种Aphis farinosa yanagicola Matsumura,1917;长管蚜亚科Macrosiphinae 1新纪录属:微小瘤蚜属Micromyzella Eastop,1955;2新纪录种:犹太微小瘤蚜Micromyzella judenkoi (Carver,1965)和香蕉交脉蚜卡拉第亚种Pentalonia nigronervosa caladii van der Goot,1917.提供了形态记述、寄主植物、分布及形态特征图.研究标本保存在英国自然历史博物馆.  相似文献   

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记述了跳小蜂科中国1新纪录属,阿奴跳小蜂属Anusia F(o)rster,及中国1新纪录种,扁角阿奴跳小蜂Anusia nasicornis F(o)rster,并给出了其形态特征图.研究标本保存在中国科学院动物研究所动物标本馆.  相似文献   

6.
记述了中国1新纪录属,髋管蓟马属Coxothrips Bournier,1963,以及2新纪录种,即驼峰髋管蓟马C.gibberosa(Kudo,1989)和塔莱髋管蓟马C.tarai(Stannard.1970);并首次描述了塔莱髋管蓟马的雄虫.总结了髋管蓟马属的属征,提供了新纪录种的形态描述、特征图以及该属中国已知种的检索表.研究标本保存于中国科学院动物研究所国家动物博物馆.  相似文献   

7.
对菊属(Dendranthema)在中国分布的10种20个居群的材料进行了细胞学研究,首次报道了异色菊(2n=18,36)、银背菊(2n=56)、楔叶菊(2n=18,72)的染色体数目和核型,以及蒙菊(2n=18)的染色体数目新纪录,并结合前人的工作,分析了菊属的核型特征和演化趋势,及其与该属分类群的关系。  相似文献   

8.
记述掘甲族Lachnogyini中国1新纪录属掘甲属Lachnogya Ménétriés,1849,及中国1新纪录种鳞掘甲Lachnogya squamosa Ménétriés,1849。提供了掘甲属Lachnogya种检索表,以及鳞掘甲Lachnogya squamosa Ménétriés,1849形态描述、分布及形态特征图。研究标本保存在河北大学博物馆。  相似文献   

9.
记述我国皿蛛科微蛛亚科新纪录属:肺音蛛属Latithorax Holm,1943;1新种:栖霞肺音蛛L.qixeiensis sp.nov。和1新纪录种:窄缝肺音蛛L.faustus (O.P.—Cambriage,1900)。  相似文献   

10.
记述了中国蚜科Aphididae长管蚜亚科Macrosiphinae 1新纪录属及1新纪录种,即水蚜属Hydaphias B(o)rner,1930,蓬子菜水蚜Hydaphias hofmanni B(o)rner,1950.提供了形态描述、寄主植物、分布及形态特征图.研究标本保存在中国科学院动物研究所动物标本馆.  相似文献   

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正Dear Editor,In December 2019, a novel human coronavirus caused an epidemic of severe pneumonia(Coronavirus Disease 2019,COVID-19) in Wuhan, Hubei, China(Wu et al. 2020; Zhu et al. 2020). So far, this virus has spread to all areas of China and even to other countries. The epidemic has caused 67,102 confirmed infections with 1526 fatal cases  相似文献   

15.
Curcumin is the yellow pigment of turmeric that interacts irreversibly forming an adduct with thioredoxin reductase (TrxR), an enzyme responsible for redox control of cell and defence against oxidative stress. Docking at both the active sites of TrxR was performed to compare the potency of three naturally occurring curcuminoids, namely curcumin, demethoxy curcumin and bis-demethoxy curcumin. Results show that active sites of TrxR occur at the junction of E and F chains. Volume and area of both cavities is predicted. It has been concluded by distance mapping of the most active conformations that Se atom of catalytic residue SeCYS498, is at a distance of 3.56 from C13 of demethoxy curcumin at the E chain active site, whereas C13 carbon atom forms adduct with Se atom of SeCys 498. We report that at least one methoxy group in curcuminoids is necessary for interation with catalytic residues of thioredoxin. Pharmacophore of both active sites of the TrxR receptor for curcumin and demethoxy curcumin molecules has been drawn and proposed for design and synthesis of most probable potent antiproliferative synthetic drugs.  相似文献   

16.
The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

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For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

19.
Å. Berg 《Bird Study》2013,60(2):153-165
CapsuleThe amount of forest (at local and landscape scales) and occurrence of residual habitats at the local scale are shown to be the major factors influencing bird community composition in farmland–forest landscapes in central Sweden.

Aims To investigate the importance of local habitat and landscape structure for breeding birds in farmland–forest landscapes in central Sweden.

Methods Breeding birds were censused at 292 points. A detailed habitat mapping was made within 300 m of the points. Within a 300–600 m radius only two major habitats (forests and arable fields) were identified.

Results Cluster analyses of bird communities identified three site types that also differed in habitat composition: (i) partially forested sites in forested landscapes; (ii) heterogeneous sites with residual habitats in mosaic landscapes; and (iii) field-dominated farmland sites in open landscapes. A total of 19 of 25 farmland bird species (restricted to farmland or using both farmland and forest) had the highest abundance in farmland sites with mosaics of forest and farmland, while only six farmland species had the highest abundance in field-dominated sites. The bird community changed from being dominated by farmland species to being dominated by forest species (common in forest landscapes without farmland) at small proportions (10–20%) of forest at the local scale. A major difference in habitat composition between heterogeneous and field-dominated sites was the occurrence of different residual habitats (e.g. shrubby areas and seminatural grasslands). These habitats seemed to influence bird community composition more than land-use, despite covering <10% of the area. Seminatural grasslands were important for bird community composition and species-richness, but grazing seemed to be less important. Among different land-use types, cereal crops were the least preferred fields. Set-asides with tall vegetation and short rotation coppices were positively associated with species-richness of farmland birds.

Conclusion In general, the composition of the landscape was important for bird community composition, although amount and distribution of forests, occurrence of residual habitats and land-use of fields at the local scale had the strongest influence on bird community composition. The possible implications of these patterns for managing farmland–forest landscapes are discussed.  相似文献   

20.
This work describes the isolation and characterization of twenty-nine compounds from the fruits of Rhus typhina L., including eleven flavonoids (1–11), eleven phenols (12–22), two pentacyclic triterpenes (23–24), two organic acids (25–26), one lumichrome (27), one courmarin (28) and one pyrimidine (29) on the basis of their spectroscopic data. Compounds apigenin (1), daidzein (4), orobol (5), 3′, 5, 5′, 7-tetrahydroxyflavanone (6), naringenin (7), butein (8), (-)-catechin (9), quercetin-3-O-α-L-(3″-O-galloyl)-rhamnoside (11), 2-hydroxybenzoic acid (13), 4-hydroxybenzaldehyde (14), vanillin (15), methyl 3,4-dihydroxybenzoate (16), 3,5-dihydroxybenzamide (18), tyrosol (19), caffeic acid (20), 3-(2,4,6-trihydroxyphenyl)-1-(4-hydroxyphenyl)-propan-1-one (21), phlorizin (22), friedelin (23), oleanolic acid (24), 4,4-dimethyl-heptanedioic acid (25), anthranilic acid (26), lumichrome (27), scoparone (28) and uracil (29) have not been recorded before in this plant. This is the first report on the occurrence of compounds 4–7, 9, 11, 13–14, 16, 18–21, 25–29 from the genus Rhus. Moreover, the chemotaxonomic significance of these isolated compounds was also summarized.  相似文献   

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