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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
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The intraganglionic laminar endings in the esophagus of the cat and the rhesus monkey show absolute equivalence between the results in both species from the morphological standpoint. The different types of apparatus found are described, with their location in the esophagus and their percentage distribution in relation to the different portions of its wall. The osmium tetroxide-zinc iodide technique gives pictures equivalent to those using silver impregnations, with the added advantage that the former brings out the morphological details more clearly, to the point of showing up the peculiar characteristics of the edges with their thorn-like protrusions. The complete independence of these structures within the ganglion is confirmed, and evidence is provided for rejecting the possibility that they might be dendritic prolongations of the neuronal elements composing the intramural ganglia. A possible afferent function is proposed, which, however, must be considered an open question, pending the results of further experimental investigation. 相似文献
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C. Vidal J.F. Menudet P. Cinquin J. Troccaz G. Morel J. Szewczyk J.J. Rambeaud J.A. Long P. Mozer 《IRBM》2010,31(2):122-126
This article presents work carried out as part of the robot sécurisé d’assistance à la chirurgie endoscopique (Rosace) project (funding ANR TecSan06), involving both academic and clinical partners along with an industrial partner in charge of technology integration. The main subject is a lightweight and compact robot for assistance in the endoscopic surgery field. The goal of the project has been to improve then transfer on a medical-grade product some technologies initially developed by the two academic partners. These technologies are: a first prototype of a robotic endoscope holder, an original method for visual servoing based on instrument tracking and some work done on comanipulation concept which consists in synergic interaction between robot and user. In accordance with the initial goals, major improvements have been obtained on these three aspects of the project. Robotic architecture improvement has contributed to enhance robot's versatility while robot command has been made more efficient and simple to use thanks to instrument tracking and comanipulation. After this 3-year project, initial prototype has turned into a commercially available product integrating (or that will integrate in a few months) these new technologies. 相似文献
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Morphological assessment of the Octopus vulgaris species complex evaluated in light of molecular‐based phylogenetic inferences 下载免费PDF全文
Michael D. Amor Mark D. Norman Alvaro Roura Tatiana S. Leite Ian G. Gleadall Amanda Reid Catalina Perales‐Raya Chung‐Cheng Lu Colin J. Silvey Erica A. G. Vidal Frederick G. Hochberg Xiaodong Zheng Jan M. Strugnell 《Zoologica scripta》2017,46(3):275-288
Cryptic species are common in the ocean, particularly among marine invertebrates such as octopuses. Delineating cryptic species is particularly problematic in octopus taxonomy where the plasticity recorded among taxonomic characters often results in low resolution at the species level. This study investigated the morphological relationships among seven phylogenetic clades (identified using cytochrome c oxidase subunit I) of the broadly distributed Octopus vulgaris species complex and close relatives. Morphological analyses in this study were successful in delimiting O. sinensis, Brazilian O. vulgaris and O. vulgaris sensu stricto, which was congruent with the molecular findings of this study. Analyses based on male morphology were successful in distinguishing 14 of 15 total pairwise comparisons and proved to be a more reliable indicator of species‐level relationships in comparison with female morphology. The majority of characters with the greatest discriminatory power were male sexual traits. Significant morphological differences were also recorded among sampling localities of conspecifics, with phenotype showing correlation with local environmental data. The findings of this study support the hypothesis that multiple O. vulgaris‐like species are currently being incorrectly treated under a single species name, O. vulgaris. Octopuses being exported globally under the name O. vulgaris are of extremely high fisheries market value and profile. Our findings have potentially significant implications for the naming and conservation of commercially harvested members of this species complex throughout their ranges. 相似文献
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Isolation and properties of an inhibitor of phospholipase A from Bothrops neuwiedii venom 总被引:1,自引:0,他引:1
An inhibitor of phoapholipase A has been isolated from Bothrops neuwiedii venom after gel filtrations through Sephadex G-50 (pH 4.5), Sephadex G-25 (pH 7.6), Sephadex G-15 (pH 4.0), and chromatography on SE-Sephadex C-25 (pH 4.2–4.5). When subjected to paper electrophoresis, the inhibitor migrates as a simple compound with isoelectric point near pH 6.8. Aminoacid composition, sensitivity toward proteases, and the absorption spectrum fit in well with a polypeptide structure lacking tyrosine and tryptophan. In the absence of EDTA, an inactive, anionic derivative appears in inhibitor preparations; the reaction can be reversed by 2-mercaptoethanol. Direct interaction of enzyme and inhibitor is proved by the inhibition of enzyme activity and the chromatography of enzyme-inhibitor mixtures. Titration of inhibitor with venom phospholipases A (isoenzymes P-1 and P-2) yields sigmoid-shaped concentration-inhibition curves, with P-1 far more sensitive than P-2. The enzyme-inhibitor interaction depends on pH since it is tight at pH 4.5 but does not occur at pH 7.5. Presence of thiol groups in inhibitor is consistent with (a) characteristic spectral changes after reaction of inhibitor with PMB 4 and NEM; (b) the inhibitor inhibition by PMB, NEM, iodoacetate, and Hg2+, and (c) the reversal of PMB inhibition with reduced glutathione. Since phospholipase A is insensitive towards Hg2+, addition of Hg2+ to enzyme-inhibitor mixtures (or crude venom samples) causes an apparent enzyme activation (deinhibition). When substrate (egg-yolk lipoprotein) is added to enzyme-inhibitor mixtures, the reaction kinetics show an initial “lag-period” which is proportional to the inhibitor concentration. The “lag-period” does not occur in the absence of inhibitor or in the presence of Hg2+, that inactivates the inhibitor. 相似文献
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Dr. August Grinzberger 《Plant Systematics and Evolution》1909,59(10):393-398
Ohne Zusammenfassung 相似文献
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Dr. August v. Hayek 《Plant Systematics and Evolution》1910,60(3):89-93
Ohne Zusammenfassung 相似文献