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排序方式: 共有1103条查询结果,搜索用时 15 毫秒
1.
叉茎管蚜蝇属Tigridemyia与墨管蚜蝇属 Mesembrius和美管蚜蝇属 Mallota形态相似,过去曾被作为后二属的亚属.但此属的雄性外生殖器阳茎的射精管端部4分叉与墨管蚜蝇属和美管蚜蝇属区别明显,因此,其属地位应予肯定.作者在整理中国的食蚜蝇标本时,发现该属1新种,刺腿叉茎管蚜蝇Tigridemyia acanthogemurilis sp.nov,加之过去已记录的1种,我国已知叉茎管蚜蝇属2种.本文描述了新种,并给出了中国已知2种的检索表和形态特征图及其分布.模式标本保存于华南农业大学植保系昆虫标本室. 相似文献
2.
C. PRADO E CASTRO A. SERRANO P. MARTINS DA SILVA M. D. GARCÍA 《Medical and veterinary entomology》2012,26(4):417-431
Information on Diptera community, seasonality and successional patterns in every geographical region is fundamental for the use of flies as forensic indicators of time of death. In order to obtain these data from the Lisbon area (Portugal), experiments were conducted during the four seasons of the year, using piglet carcasses as animal models. Five stages were recognized during the decomposition process. The stages, besides visually defined, could be separated taking into account the occurrence and abundance of the specific groups of Diptera collected. In general, the bloated stage recorded higher abundance and species‐richness values. Seventy‐one species were identified, belonging to 39 families, in a total of 20 144 adult Diptera collected. Autumn yielded the highest values of species richness, whereas winter had the lowest. In all seasons of the year, Calliphoridae was the dominant family; Muscidae and Fanniidae were very abundant as well. Calliphora vicina Robineau‐Desvoidy, Calliphora vomitoria (Linnaeus), Chrysomya albiceps (Wiedemann), Lucilia ampullacea Villeneuve, Lucilia caesar (Linnaeus), Lucilia sericata (Meigen) (Calliphoridae), Hydrotaea ignava (Harris), Muscina prolapsa (Harris), Synthesiomyia nudiseta (van der Wulp) (Muscidae), Piophila megastigmata McAlpine, Stearibia nigriceps (Meigen) (Piophilidae) and Nemopoda nitidula (Fallén) (Sepsidae) were revealed to be very important members of the Diptera community collected. The necrophagous behaviour, demonstrated by their immatures, using carrion as a food source makes them useful forensic indicator species. Also of relevance is the presence of Chrysomya megacephala (Fabricius), S. nudiseta and P. megastigmata, foreign species established in the local carrion communities. This study also marks the first record of S. nudiseta in Portugal. 相似文献
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4.
Dr. August Grinzberger 《Plant Systematics and Evolution》1909,59(10):393-398
Ohne Zusammenfassung 相似文献
5.
Dr. August v. Hayek 《Plant Systematics and Evolution》1910,60(3):89-93
Ohne Zusammenfassung 相似文献
6.
August Neilreich 《Plant Systematics and Evolution》1860,10(4):115-118
Ohne Zusammenfassung 相似文献
7.
Sergey A. Dergunov Elizabeth A. Bowles Weston Gordon Michael Green August Bierman Mary L. Ellsworth Eugene Pinkhassik Randy S. Sprague 《Biochemistry and Biophysics Reports》2015
ATP release from erythrocytes in response to low oxygen tension requires an increase in cAMP, the level of which is regulated by phosphodiesterase 3 (PDE3). Such release is defective in erythrocytes of humans with type 2 diabetes (DM2). This study tested a hypothesis that direct delivery of the clinically useful PDE3 inhibitor, cilostazol, to erythrocytes of humans with type 2 diabetes using liposomes would restore low-oxygen tension-induced ATP release. Cilostazol was incorporated into liposomes prepared from dimyristoylphosphatidylcholine (DMPC). Liposome-delivery of cilostazol restored ATP release from DM2 erythrocytes to levels which were not different from that released from non-cilostazol treated healthy erythrocytes under the same conditions. There were no observed adverse effects of the liposomes on either healthy or DM2 erythrocytes. The directed liposomal delivery of PDE inhibitors to erythrocytes may help prevent or slow the development of peripheral vascular disease in individuals with DM2 by restoring an important physiological controller of microvascular perfusion while minimizing side effects associated with systemic delivery of some of these inhibitors. 相似文献
8.
Kevin Ruddock Peter V. August Christopher Damon Charles LaBash Pamela Rubinoff Donald Robadue 《PloS one》2013,8(11)
Climate change will affect the composition of plant and animal communities in many habitats and geographic settings. This presents a dilemma for conservation programs – will the portfolio of protected lands we now have achieve a goal of conserving biodiversity in the future when the ecological communities occurring within them change? Climate change will significantly alter many plant communities, but the geophysical underpinnings of these landscapes, such as landform, elevation, soil, and geological properties, will largely remain the same. Studies show that extant landscapes with a diversity of geophysical characteristics support diverse plant and animal communities. Therefore, geophysically diverse landscapes will likely support diverse species assemblages in the future, although which species and communities will be present is not altogether clear. Following protocols advanced in studies spanning large regions, we developed a down-scaled, high spatial resolution measure of geophysical complexity based on Ecological Land Units (ELUs) and examined the relationship between plant species richness, ecological community richness, and ELU richness (number of different ELU types). We found that extant landscapes with high ELU richness had a greater variety of ecological community types and high species richness of trees, shrubs, and herbaceous plants. We developed a spatial representation of diverse ELU landscapes to inform local conservation practitioners, such as land trusts, of potential conservation targets that will likely support diverse faunas and floras despite the impact of climate change. 相似文献
9.
Zusammenfassung Es wird das Verhalten des Magnesiums im Mycel von Aspergillus niger untersucht. Mit organischen Lösungsmitteln (Alkohol, Äther, Schwefelkohlenstoff, Chloroform, Aceton) konnte kein Magnesium herausgelöst werden; jedenfalls könnten nur kaum faßbare Spuren in Betracht kommen. In dieser Hinsicht zeigt sich das Pilzmycel quantitativ, vielleicht auch qualitativ, deutlich verschieden auch von etiolierten Teilen grüner Pflanzen (Rissmann).Der Magnesiumgehalt geht während Wachstum und Autolyse dem Aschengehalt nicht parallel; namentlich nimmt während der Autolyse auf saurem Substrat der Magnesiumgehalt des Mycels sehr viel weniger ab als der Aschengehalt. Daraus läßt sich vielleicht der Schluß ziehen, daß hier organische Magnesiumverbindungen anderer Natur vorliegen als solche, die in Aceton usw. löslich sind. 相似文献
10.
August Hayek 《Plant Systematics and Evolution》1921,70(1-2):12-22
Ohne Zusammenfassung 相似文献