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Summary After inducing experimentally a stenosis of the aorta abdominalis in rabbits, the mitochondria of the aortic endothelium were fluorescence-optically demonstrated, and quantitatively investigated above as well as below the stenosis. The changes in the number of the mitochondria are proportional to the values of blood pressure, and are discussed in relation to changes in the shape of the endothelial cells. 相似文献
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M De Mendo?a P Guicheney P Meyer 《Comptes rendus des séances de l'Académie des sciences. Série D, Sciences naturelles》1978,286(12):965-968
Plasma noradrenaline and adrenaline were measured in conscious Rats on 50 microliter samples by a radiometric technique. In normotensive Rats a moderate haemorrhage increased catecholamine levels. In Rats rendered hypertensive by salt loading and by desoxycorticosterone treatment noradrenaline levels were increased. 相似文献
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Carlton JM Adams JH Silva JC Bidwell SL Lorenzi H Caler E Crabtree J Angiuoli SV Merino EF Amedeo P Cheng Q Coulson RM Crabb BS Del Portillo HA Essien K Feldblyum TV Fernandez-Becerra C Gilson PR Gueye AH Guo X Kang'a S Kooij TW Korsinczky M Meyer EV Nene V Paulsen I White O Ralph SA Ren Q Sargeant TJ Salzberg SL Stoeckert CJ Sullivan SA Yamamoto MM Hoffman SL Wortman JR Gardner MJ Galinski MR Barnwell JW Fraser-Liggett CM 《Nature》2008,455(7214):757-763
The human malaria parasite Plasmodium vivax is responsible for 25-40% of the approximately 515 million annual cases of malaria worldwide. Although seldom fatal, the parasite elicits severe and incapacitating clinical symptoms and often causes relapses months after a primary infection has cleared. Despite its importance as a major human pathogen, P. vivax is little studied because it cannot be propagated continuously in the laboratory except in non-human primates. We sequenced the genome of P. vivax to shed light on its distinctive biological features, and as a means to drive development of new drugs and vaccines. Here we describe the synteny and isochore structure of P. vivax chromosomes, and show that the parasite resembles other malaria parasites in gene content and metabolic potential, but possesses novel gene families and potential alternative invasion pathways not recognized previously. Completion of the P. vivax genome provides the scientific community with a valuable resource that can be used to advance investigation into this neglected species. 相似文献
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Pain A Böhme U Berry AE Mungall K Finn RD Jackson AP Mourier T Mistry J Pasini EM Aslett MA Balasubrammaniam S Borgwardt K Brooks K Carret C Carver TJ Cherevach I Chillingworth T Clark TG Galinski MR Hall N Harper D Harris D Hauser H Ivens A Janssen CS Keane T Larke N Lapp S Marti M Moule S Meyer IM Ormond D Peters N Sanders M Sanders S Sargeant TJ Simmonds M Smith F Squares R Thurston S Tivey AR Walker D White B Zuiderwijk E Churcher C Quail MA Cowman AF Turner CM Rajandream MA Kocken CH 《Nature》2008,455(7214):799-803
Plasmodium knowlesi is an intracellular malaria parasite whose natural vertebrate host is Macaca fascicularis (the 'kra' monkey); however, it is now increasingly recognized as a significant cause of human malaria, particularly in southeast Asia. Plasmodium knowlesi was the first malaria parasite species in which antigenic variation was demonstrated, and it has a close phylogenetic relationship to Plasmodium vivax, the second most important species of human malaria parasite (reviewed in ref. 4). Despite their relatedness, there are important phenotypic differences between them, such as host blood cell preference, absence of a dormant liver stage or 'hypnozoite' in P. knowlesi, and length of the asexual cycle (reviewed in ref. 4). Here we present an analysis of the P. knowlesi (H strain, Pk1(A+) clone) nuclear genome sequence. This is the first monkey malaria parasite genome to be described, and it provides an opportunity for comparison with the recently completed P. vivax genome and other sequenced Plasmodium genomes. In contrast to other Plasmodium genomes, putative variant antigen families are dispersed throughout the genome and are associated with intrachromosomal telomere repeats. One of these families, the KIRs, contains sequences that collectively match over one-half of the host CD99 extracellular domain, which may represent an unusual form of molecular mimicry. 相似文献
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Struck TH Paul C Hill N Hartmann S Hösel C Kube M Lieb B Meyer A Tiedemann R Purschke G Bleidorn C 《Nature》2011,471(7336):95-98
Annelida, the ringed worms, is a highly diverse animal phylum that includes more than 15,000 described species and constitutes the dominant benthic macrofauna from the intertidal zone down to the deep sea. A robust annelid phylogeny would shape our understanding of animal body-plan evolution and shed light on the bilaterian ground pattern. Traditionally, Annelida has been split into two major groups: Clitellata (earthworms and leeches) and polychaetes (bristle worms), but recent evidence suggests that other taxa that were once considered to be separate phyla (Sipuncula, Echiura and Siboglinidae (also known as Pogonophora)) should be included in Annelida. However, the deep-level evolutionary relationships of Annelida are still poorly understood, and a robust reconstruction of annelid evolutionary history is needed. Here we show that phylogenomic analyses of 34 annelid taxa, using 47,953 amino acid positions, recovered a well-supported phylogeny with strong support for major splits. Our results recover chaetopterids, myzostomids and sipunculids in the basal part of the tree, although the position of Myzostomida remains uncertain owing to its long branch. The remaining taxa are split into two clades: Errantia (which includes the model annelid Platynereis), and Sedentaria (which includes Clitellata). Ancestral character trait reconstructions indicate that these clades show adaptation to either an errant or a sedentary lifestyle, with alteration of accompanying morphological traits such as peristaltic movement, parapodia and sensory perception. Finally, life history characters in Annelida seem to be phylogenetically informative. 相似文献
110.
We present a step-by-step approach for constructing a framework for knowledge process analysis (KPA). We intend to apply this framework to the analysis of own research projects in an exploratory way and elaborate it through the accumulation of case studies. This study is based on a methodology consisting of knowledge process modeling, primitives synthesis, and reflective verification. We describe details of the methodology and present the results of case studies: a novel methodology, a practical work guide, and a tool for KPA; insights for improving future research projects and education; and the integration of existing knowledge creation theories. 相似文献