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701.
Planta - In vorliegender Abhandlung wird über starke morphologische Veränderungen an Rotklee-Pflanzen (Trifolium pratense) durch den Einfluß synthetischer Wuchs- und Hemmstoffe... 相似文献
702.
Though recovery of consciousness after drug overdose may occur within a day or two, the drug itself may not finally leave the brain for another one to three weeks, and at this late time a withdrawal syndrome can occur, with insomnia, restlessness, raised paradoxical (R.E.M.) sleep, epileptic phenomena, and even delirium. It is proposed that a high degree of drug-tolerance and dependence can be rapidly acquired after overdose.Abnormal sleep features of 10 patients resolved only slowly over a period of up to two months after overdose. The data support the view that R.E.M. sleep is concerned with processes of brain repair. 相似文献
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Felix Oswald Aravindan Varadarajan Holger Lill Erwin?J.G. Peterman Yves?J.M. Bollen 《Biophysical journal》2016,110(5):1139-1149
The functional organization of prokaryotic cell membranes, which is essential for many cellular processes, has been challenging to analyze due to the small size and nonflat geometry of bacterial cells. Here, we use single-molecule fluorescence microscopy and three-dimensional quantitative analyses in live Escherichia coli to demonstrate that its cytoplasmic membrane contains microdomains with distinct physical properties. We show that the stability of these microdomains depends on the integrity of the MreB cytoskeletal network underneath the membrane. We explore how the interplay between cytoskeleton and membrane affects trans-membrane protein (TMP) diffusion and reveal that the mobility of the TMPs tested is subdiffusive, most likely caused by confinement of TMP mobility by the submembranous MreB network. Our findings demonstrate that the dynamic architecture of prokaryotic cell membranes is controlled by the MreB cytoskeleton and regulates the mobility of TMPs. 相似文献
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Peter-Paul Henri Marie Delnoy Klaus-Jürgen Gutleben Niels Eske Bruun Sebastian K.G. Maier Hanno Oswald Christoph Stellbrink Jens Brock Johansen Stefan Paule Peter Søgaard 《Indian pacing and electrophysiology journal》2021,21(4):209-218
BackgroundIn patients with cardiac resynchronization therapy defibrillators (CRT-Ds), intracardiac impedance measured by dedicated CRT-D software may be used to monitor hemodynamic changes. We investigated the relationship of hemodynamic parameters assessed by intracardiac impedance and by echocardiography in a controlled clinical setting.MethodsThe study enrolled 68 patients (mean age, 66 ± 9 years; 74% males) at 12 investigational sites. The patients had an indication for CRT-D implantation, New York Heart Association class II/III symptoms, left ventricular ejection fraction 15%–35%, and a QRS duration ≥150 ms. Two months after a CRT-D implantation, hemodynamic changes were provoked by overdrive pacing. Intracardiac impedance was recorded at rest and at four pacing rates ranging from 10 to 40 beats/min above the resting rate. In parallel, echocardiography measurements were performed. We hypothesized that a mean intra-individual correlation coefficient (rmean) between stroke impedance (difference between end-systolic and end-diastolic intracardiac impedance) measured by CRT-D and the aortic velocity time integral (i.e., stroke volume) determined by echocardiography would be significantly larger than 0.65.ResultsThe hypothesis was evaluated in 40 patients with complete data sets. The rmean was 0.797, with a lower confidence interval bound of 0.709. The study hypothesis was met (p = 0.007). A stepwise reduction of stroke impedance and stroke volume was observed with increasing heart rate.ConclusionsIntracardiac impedance measured by implanted CRT-Ds correlated well with the aortic velocity time integral (stroke volume) determined by echocardiography. The impedance measurements bear potential and are readily available technically, not requiring implantation of additional material beyond standard CRT-D system. 相似文献
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Cytotoxic effect of multinucleation in HeLa cell cultures associated with the presence of Vir plasmid in Escherichia coli strains 总被引:6,自引:0,他引:6
Eric Oswald Jean De Rycke Jean François Guillot Roger Boivin 《FEMS microbiology letters》1989,58(1):95-99
The occurrence activity and localization of calmodulin in three heterocystous cyanobacteria of the genus Anabaena were studied. Boiled crude extracts caused a Ca2+-dependent stimulation of NAD kinase. Such a stimulation was blocked by EGTA and chlorpromazine, SDS-PAGE and Western blot analysis using antiserum against eukaryotic spinach calmodulin, revealed a polypeptide of about 17 kDa. Immunogold localization of calmodulin gave a dense gold label in both vegetative cells and heterocysts. The label was mainly confined to the centroplasm in vegetative cells, while it was evenly distributed in the cytoplasm of mature heterocysts. 相似文献