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31.
Erika Birkholz 《Protoplasma》1931,13(1):282-321
Ohne ZusammenfassungEs ist mir eine angenehme Pflicht Herrn Prof. Dr. Mez und Herrn Privatdoz. Dr. Ziegenspeck den schuldigen Dank für die Anregung und letzterem auch für die Unterstützung und Überlassung der Apparatur auszusprechen. 相似文献
32.
Erika Kern-Bontke 《Histochemistry and cell biology》1964,4(1):56-64
Zusammenfassung An 35 Corpora lutea, gewonnen bei gynäkologischen Operationen, wurden histochemisch 18 Fermentnachweise geprüft. Dabei ergab sich ein Unterschied im Fermentgehalt der Theca- und Granulosaluteinzellen. Es wird diskutiert, ob diese Befunde mit der Progesteron- und östrogensynthese im Ovar im Zusammenhang stehen.Der Deutschen Forschungsgemeinschaft danke ich für die Unterstützung dieses Arbeits-programms. 相似文献
33.
Für eine effiziente Resistenzzüchtung stellt eine Resistenzprüfmethode, die eine schnelle und zuverlässige Evaluierung einer möglichst großen Zahl von Genotypen erlaubt, eine wichtige Voraussetzung dar. Für das Freiland wurde eine Preßluftinjektionsmethode entwickelt, die eine nahezu 100 %ige Infektion von Maispflanzen mit dem Zuckerrohrmosaik‐Virus (sugarcane mosaic virus, SCMV) und dem Maisver‐zwergungsmosaik‐Virus (maize dwarf mosaic virus, MDMV) garantiert. Bei den empfindlicheren Pflanzen im Gewächshaus hatte eine mechanische Inokulation von Hand Vorteile. 相似文献
34.
Luttge Ulrich; Osmond C. Barry; Ball Erika; Brinckmann Enno; Kinze Gabriele 《Plant & cell physiology》1972,13(3):505-514
Bisulfite compounds are shown to be nonspecific inhibitors ofphotosynthetic processes and of ion transport in green tissues.CO2 fixation and light-dependent transient changes in externalpH are inhibited about 50% by 5x104 M glyoxal-Na-bisulfite.Chloride uptake in the light and in the dark is inhibited tothe same extent at this concentration. At 5x103 M theinhibitor reduces ATP levels in the light and in the dark, andeffects on glycolate oxidase and PEP carboxylase are observed.The extent of inhibition is dependent on time of treatment withglyoxal-Na-bisulfite and freshly prepared NaHSO3 is equallyas effective as the addition compound. Possible explanations of the bisulfite effects and the relationshipsto SO2 effects on photosynthesis are discussed. (Received September 1, 1971; ) 相似文献
35.
Erika C. Freeman Irena F. Creed Blake Jones Ann‐Kristin Bergstrm 《Global Change Biology》2020,26(9):4966-4987
The interacting effects of global changes—including increased temperature, altered precipitation, reduced acidification and increased dissolved organic matter loads to lakes—are anticipated to create favourable environmental conditions for cyanobacteria in northern lakes. However, responses of cyanobacteria to these global changes are complex, if not contradictory. We hypothesized that absolute and relative biovolumes of cyanobacteria (both total and specific genera) are increasing in Swedish nutrient‐poor lakes and that these increases are associated with global changes. We tested these hypotheses using data from 28 nutrient‐poor Swedish lakes over 16 years (1998–2013). Increases in cyanobacteria relative biovolume were identified in 21% of the study sites, primarily in the southeastern region of Sweden, and were composed mostly of increases from three specific genera: Merismopedia, Chroococcus and Dolichospermum. Taxon‐specific changes were related to different environmental stressors; that is, increased surface water temperature favoured higher Merismopedia relative biovolume in low pH lakes with high nitrogen to phosphorus ratios, whereas acidification recovery was statistically related to increased relative biovolumes of Chroococcus and Dolichospermum. In addition, enhanced dissolved organic matter loads were identified as potential determinants of Chroococcus suppression and Dolichospermum promotion. Our findings highlight that specific genera of cyanobacteria benefit from different environmental changes. Our ability to predict the risk of cyanobacteria prevalence requires consideration of the environmental condition of a lake and the sensitivities of the cyanobacteria genera within the lake. Regional patterns may emerge due to spatial autocorrelations within and among lake history, rates and direction of environmental change and the niche space occupied by specific cyanobacteria. 相似文献
36.
Clemens Alexander Boecker Mara A. Olenick Elizabeth R. Gallagher Michael E. Ward Erika L. F. Holzbaur 《Traffic (Copenhagen, Denmark)》2020,21(1):138-155
Induced pluripotent stem cells (iPSCs) hold promise to revolutionize studies of intracellular transport in live human neurons and to shed new light on the role of dysfunctional transport in neurodegenerative disorders. Here, we describe an approach for live imaging of axonal and dendritic transport in iPSC‐derived cortical neurons. We use transfection and transient expression of genetically‐encoded fluorescent markers to characterize the motility of Rab‐positive vesicles, including early, late and recycling endosomes, as well as autophagosomes and mitochondria in iPSC‐derived neurons. Comparing transport parameters of these organelles with data from primary rat hippocampal neurons, we uncover remarkable similarities. In addition, we generated lysosomal‐associated membrane protein 1 (LAMP1)‐enhanced green fluorescent protein (EGFP) knock‐in iPSCs and show that knock‐in neurons can be used to study the transport of endogenously labeled vesicles, as a parallel approach to the transient overexpression of fluorescently labeled organelle markers. 相似文献
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38.
Pedrotta Tiziana Gobet Erika Schwörer Christoph Beffa Giorgia Butz Christoph Henne Paul D. Morales-Molino César Pasta Salvatore van Leeuwen Jacqueline F. N. Vogel Hendrik Zwimpfer Elias Anselmetti Flavio S. Grosjean Martin Tinner Willy 《Vegetation History and Archaeobotany》2021,30(6):789-813
Vegetation History and Archaeobotany - Knowledge about the vegetation history of Sardinia, the second largest island of the Mediterranean, is scanty. Here, we present a new sedimentary record... 相似文献
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40.
Tóth Ákos Bata-Vidács Ildikó Kosztik Judit Máté Rózsa Kutasi József Tóth Erika Bóka Károly Táncsics András Nagy István Kovács Gábor Kukolya József 《Antonie van Leeuwenhoek》2021,114(10):1575-1584
Antonie van Leeuwenhoek - A Gram-reaction-negative halotolerant bacterial strain, designated Ka21T, was isolated from agricultural soil and characterised using a polyphasic approach to determine... 相似文献