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Bacteriomorphic organisms found in fruits of capitate infructescences in Kunduricarpus Kodrul, N. Maslova, Tekleva et Golovneva, Platanaceae, are described. Three types of carpel damage have been detected: (1) evidence of penetration of microorganisms in the walls of the carpel, (2) three-dimensional structures (isolated and in chains) rounded in section, which fill the inner space of the carpel, and (3) imprints of these structures on the inner surface of the carpel wall cuticle. The possible nature of the microorganisms is discussed. 相似文献
74.
M. Fernando Gonzalez-Zalba Chiara Ciccarelli Liviu P. Zarbo Andrew C. Irvine Richard C. Campion Bryan L. Gallagher Tomas Jungwirth Andrew J. Ferguson Joerg Wunderlich 《PloS one》2015,10(4)
We propose a novel hybrid single-electron device for reprogrammable low-power logic operations, the magnetic single-electron transistor (MSET). The device consists of an aluminium single-electron transistor with a GaMnAs magnetic back-gate. Changing between different logic gate functions is realized by reorienting the magnetic moments of the magnetic layer, which induces a voltage shift on the Coulomb blockade oscillations of the MSET. We show that we can arbitrarily reprogram the function of the device from an n-type SET for in-plane magnetization of the GaMnAs layer to p-type SET for out-of-plane magnetization orientation. Moreover, we demonstrate a set of reprogrammable Boolean gates and its logical complement at the single device level. Finally, we propose two sets of reconfigurable binary gates using combinations of two MSETs in a pull-down network. 相似文献
75.
István A. Krizbai ákos Gasparics Péter Nagy?szi Csilla Fazakas Judit Molnár Imola Wilhelm Rita Bencs László Rosivall Attila Sebe 《PloS one》2015,10(3)
Cancer progression towards metastasis follows a defined sequence of events described as the metastatic cascade. For extravasation and transendothelial migration metastatic cells interact first with endothelial cells. Yet the role of endothelial cells during the process of metastasis formation and extravasation is still unclear, and the interaction between metastatic and endothelial cells during transendothelial migration is poorly understood. Since tumor cells are well known to express TGF-β, and the compact endothelial layer undergoes a series of changes during metastatic extravasation (cell contact disruption, cytoskeletal reorganization, enhanced contractility), we hypothesized that an EndMT may be necessary for metastatic extravasation. We demonstrate that primary cultured rat brain endothelial cells (BEC) undergo EndMT upon TGF-β1 treatment, characterized by the loss of tight and adherens junction proteins, expression of fibronectin, β1-integrin, calponin and α-smooth muscle actin (SMA). B16/F10 cell line conditioned and activated medium (ACM) had similar effects: claudin-5 down-regulation, fibronectin and SMA expression. Inhibition of TGF-β signaling during B16/F10 ACM stimulation using SB-431542 maintained claudin-5 levels and mitigated fibronectin and SMA expression. B16/F10 ACM stimulation of BECs led to phosphorylation of Smad2 and Smad3. SB-431542 prevented SMA up-regulation upon stimulation of BECs with A2058, MCF-7 and MDA-MB231 ACM as well. Moreover, B16/F10 ACM caused a reduction in transendothelial electrical resistance, enhanced the number of melanoma cells adhering to and transmigrating through the endothelial layer, in a TGF-β-dependent manner. These effects were not confined to BECs: HUVECs showed TGF-β-dependent SMA expression when stimulated with breast cancer cell line ACM. Our results indicate that an EndMT may be necessary for metastatic transendothelial migration, and this transition may be one of the potential mechanisms occurring during the complex phenomenon known as metastatic extravasation. 相似文献
76.
Amanda L. McGuire Sophia C. Bennett Sally M. Lansley Natalia D. Popowicz Julius F. Varano della Vergiliana Daniel Wong Y. C. Gary Lee Aron Chakera 《PloS one》2015,10(3)
A major complication of peritoneal dialysis is the development of peritonitis, which is associated with reduced technique and patient survival. The inflammatory response elicited by infection results in a fibrin and debris-rich environment within the peritoneal cavity, which may reduce the effectiveness of antimicrobial agents and predispose to recurrence or relapse of infection. Strategies to enhance responses to antimicrobial agents therefore have the potential to improve patient outcomes. This study presents pre-clinical data describing the compatibility of tPA and DNase in combination with antimicrobial agents used for the treatment of PD peritonitis. tPA and DNase were stable in standard dialysate solution and in the presence of antimicrobial agents, and were safe when given intraperitoneally in a mouse model with no evidence of local or systemic toxicity. Adjunctive tPA and DNase may have a role in the management of patients presenting with PD peritonitis. 相似文献
77.
K. Solberg F. Heinemann P. Pellikaan L. Keilig C. Bourauel 《Computer methods in biomechanics and biomedical engineering》2017,20(7):770-782
The effect of implants’ number on overdenture stability and stress distribution in edentulous mandible, implants and overdenture was numerically investigated for implant-supported overdentures. Three models were constructed. Overdentures were connected to implants by means of ball head abutments and rubber ring. In model 1, the overdenture was retained by two conventional implants; in model 2, by four conventional implants; and in model 3, by five mini implants. The overdenture was subjected to a symmetrical load at an angle of 20 degrees to the overdenture at the canine regions and vertically at the first molars. Four different loading conditions with two total forces (120, 300 N) were considered for the numerical analysis. The overdenture displacement was about 2.2 times higher when five mini implants were used rather than four conventional implants. The lowest stress in bone bed was observed with four conventional implants. Stresses in bone were reduced by 61% in model 2 and by 6% in model 3 in comparison to model 1. The highest stress was observed with five mini implants. Stresses in implants were reduced by 76% in model 2 and 89% increased in model 3 compared to model 1. The highest implant displacement was observed with five mini implants. Implant displacements were reduced by 29% in model 2, and increased by 273% in model 3 compared to model 1. Conventional implants proved better stability for overdenture than mini implants. Regardless the type and number of implants, the stress within the bone and implants are below the critical limits. 相似文献
78.
Phylogeography and population differentiation in the Psittacanthus calyculatus (Loranthaceae) mistletoe: a complex scenario of climate–volcanism interaction along the Trans‐Mexican Volcanic Belt 下载免费PDF全文
79.
Janne Alahuhta Sarian Kosten Munemitsu Akasaka Dominique Auderset Mattia M. Azzella Rossano Bolpagni Claudia P. Bove Patricia A. Chambers Eglantine Chappuis John Clayton Mary de Winton Frauke Ecke Esperança Gacia Gana Gecheva Patrick Grillas Jennifer Hauxwell Seppo Hellsten Jan Hjort Mark V. Hoyer Christiane Ilg Agnieszka Kolada Minna Kuoppala Torben Lauridsen En Hua Li Balázs A. Lukács Marit Mjelde Alison Mikulyuk Roger P. Mormul Jun Nishihiro Beat Oertli Laila Rhazi Mouhssine Rhazi Laura Sass Christine Schranz Martin Søndergaard Takashi Yamanouchi Qing Yu Haijun Wang Nigel Willby Xiao Ke Zhang Jani Heino 《Journal of Biogeography》2017,44(8):1758-1769
80.
Timothy F. Murphy 《Bioethics》2015,29(5):369-377
Most advocates of biogenetic modification hope to amplify existing human traits in humans in order to increase the value of such traits as intelligence and resistance to disease. These advocates defend such enhancements as beneficial for the affected parties. By contrast, some commentators recommend certain biogenetic modifications to serve social goals. As Ingmar Persson and Julian Savulescu see things, human moral psychology is deficient relative to the most important risks facing humanity as a whole, including the prospect of Ultimate Harm, the point at which worthwhile life is forever impossible on the planet. These risks can be mitigated, they say, by enhancing moral psychology in novel ways. Persson and Savulescu argue that some parents should modify the underlying biogenetics of their children's moral psychology, if such measures were safe and effective, but they admit these interventions may not decouple humanity from Ultimate Harm. Neither are these modifications the only options, they concede, for addressing risks to humanity. Even with these concessions, saving humanity from itself is a fairly poor reason to modify the moral psychology of children. In most ways, adults would be better candidates, morally speaking, for modifications of psychology. Even then, there is no direct link between morally enhanced human beings and the hoped‐for effect of better protection from Ultimate Harm. Asserting a general duty of all to contribute to the avoidance of Ultimate Harm is a better moral strategy than intervening in the moral psychology of some, even though meeting that duty may involve substantial interference with the free exercise of one's interests. 相似文献