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681.
Dr. Margit Kovács 《Plant Ecology》1969,19(1-6):240-255
Zusammenfassung Die zum Aceri-Quercion-Verband gehörenden kontinentalen und kalkholden Corno-Quercetum Wälder sind in dem nordöstlichen Ungarischen Mittelgebirge so im Mátra-Gebirge auf Andesit, auf Kalk- und vulkanischem Grundgestein verbreitet. Einige Bestände der Corno-Quercetum Wälder stehen im Kontakt mit dem auf Lößboden (Tschernosjom-brauner Waldboden) vorhandenen Aceri tatarici-Quercetum des Flachlandes (Randgebiet der Ungarischen Tiefebene).Die artenreichen Bestände sind durch den verhältnismäßig hohen Anteil der Aceri-Quercion Charakterarten und der sog. Waldsteppenarten gut gekennzeichnet.In der floristischen Zusammensetzung des Corno-Quercetum spielen außer den obererwähnten Arten die Elemente von Quercetea pubescenti-petraeae und Querco-Fagetea die Hauptrolle.Auf Grund der Charakterisierung des Standortes der Corno-Quercetum Wälder durch die T-, W- und R-Indikatorwerte der Arten nach Zólyomi (1963, 1964) ist das Corno-Quercetum als eine relativ basischen, mäßig trockenen Standort kennzeichnende, an submediterranen wärmeliebenden Arten reiche Gesellschaft kontinentale Gepräges zu betrachten.Auf Andesit-Grundgestein entstandene Böden (Erubasboden, brauner Waldboden, Parabraunerde) des Corno-Quercetum sind reicher an adsorbiertem Ca, und das ermöglicht das Erscheinen der Bestände und so auch der Arten, die einen gewissen Kalkgehalt und eine neutrale, oder schwach basische Reaktion des Bodens beanspruchen.
Summary The author describes the Corno-Quercetum oak forests from the Mátra-Mts. in Hungary.Floristic composition indicates requirements for chalk and nitrogen. The author also includes a number of ecological data (temperature, oil-composition, humidity) measured in these forests.相似文献
682.
Dr. M. Pavelka 《Cell and tissue research》1976,165(3):371-382
Summary Electron microscopic studies of adult rat and mouse tracheal epithelium maintained in organ culture for a period of up to 6 days were performed. In specimens cultured for 60 minutes no conspicuous micromorphological alterations could be observed. Following culture periods from 1–6 days the number of cilia in some of the ciliated cells was reduced while their structure and the other ultrastructural details of the epithelial cells were preserved. In specimens cultured for 5–6 days some additional alterations could be noticed: polymorphism of mitochondria, increased number of lysosomes, appearance of intracellular vacuoles, exhaustion of goblet cells and disappearance of granulated mast-cell like cells in the rat tracheal epithelium.I want to thank Miss J. Selbmann and Mrs. S. Kolassa for technical help and Mr. H. Wagner for preparing the micrographs; I am indebted to Dr. D. Kerjaschki and to Mr. H. Hörandner for performing preparations for scanning electron microscopy and to Mr. P. Scholze (Österreichische Studiengesellschaft für Atomenergie, Institut für Metallurgie, Abteilung Fremdkörperphysik) for preparing the scanning electron micrograph.This work was supported by the Fond zur Förderung der wissenschaftlichen Forschung: Project 2099.This paper is dedicated to Prof. Bargmann on the occasion of his 70th birthday.The author wishes to express her appreciation to Prof. Stockinger for suggestion and advice. 相似文献
683.
A Ellinger M Pavelka 《Biology of the cell / under the auspices of the European Cell Biology Organization》1986,58(1):31-41
Administration of the antimicrotubular agent colchicine to adult rats (0.5 mg/100 g of body weight for 6 hr) induces formation of extended aggregates of tubular, vesicular, and cisternal organelles in the absorptive cells of the small intestine. The phosphatase reaction pattern (thiamine pyrophosphatase, acid phosphatase, acid trimetaphosphatase) suggests that the majority of them belongs to the lysosomal system (Ellinger and Pavelka, 1984). The present study extends these findings and examines the uptake and fate of intravenously injected horseradish peroxidase (HRP) at the basal and lateral cell surfaces and of intraluminally applied HRP at the apical cell surface. HRP, applied to control animals and animals pretreated with colchicine, was internalized at both apical and basolateral cell surfaces of the absorptive cells, and delivered into endosome-like vesicles, multivesiculated bodies (mvbs), dense bodies (dbs), and in several instances into Golgi cisternae. Following intraluminal application, evidence was obtained for the transport of HRP across the cell; in contrast, intravenously applied HRP was never detected at the apical cell surface. Colchicine pretreatment did not stop the uptake of HRP, which was rapidly sequestered to the clustered tubules, vesicles, and cisternae, as well as to the mvbs and dbs. After longer intervals, the portion of HRP-reactive tubules, vesicles, and cisternae within the clusters increased: 60 min after HRP-administration all of them contained HRP-activity. These results indicate that the colchicine-induced clustered organelles are recipients of endocytic materials internalized at the apical as well as at the basolateral cell surface. 相似文献
684.
Sigrid Liede-Schumann Stefan Dötterl Margit Gebauer Ulrich Meve 《Organisms Diversity & Evolution》2013,13(1):15-31
One hundred and thirty-seven accessions of Cynanchum viminale and its relatives, formerly known as Sarcostemma, were studied using randomly amplified polymorphic DNA (RAPD). A fingerprinting technique was used because sequencing had failed to differentiate between morphologically separable groups. Chromosome counts were conducted to establish the ploidy level of the accessions. The banding patterns resulting from RAPD analysis were evaluated with Canonical Analysis of Principal Coordinates, Permanova and neighbour-joining. A strong geographic component was found in the structure of the group. Taxa considered species or subspecies based on morphology often formed coherent groups. The data are interpreted to reflect at least two cycles of diversification: the first one from Madagascar and the second one most likely from the East African–Arabian region, reaching Madagascar again. In mainland Africa, polyploidisation has occurred several times. 相似文献
685.
E. Pindurov�� A. ?ourkov�� J. Zr?stov�� J. Ju?ica A. Pavelka 《Molecular biotechnology》2013,53(1):29-40
High-resolution melting curve analysis (HRM) of polymerase chain reaction (PCR) amplicons has been described as a fast, cheap, and reliable closed-tube method of genotyping with no need for labeled primers or labeled probes. We adapted this melting analysis assay for the detection of the most common nonfunctional alleles of cytochrome P-450 (CYP) 2D6 in the Caucasian population that affect the metabolism of many commonly used drugs. We used this method to genotype 91 patients under paroxetine therapy. The presence and the constitution of the most common single-nucleotide polymorphisms (1846G>A, 2988G>A, 100C>T, 2549delA, 2615_2617delAAG, and 1707delT) in poor and intermediate metabolizers from the Caucasian population were detected in short amplicons (??148 bp). After fluorescence normalization, the wild-type, homozygous, and heterozygous samples were easily distinguishable from each other by their specific melting curve shape. A total of 92.6% of the 1846G>A heterozygotes, 96% of the 100C>T heterozygotes, and 100% of the 2988G>A, 2549delA, 2615_2617delAAG, and 1707delT heterozygotes have been correctly distinguished from the wild types. One hundred percent of all the homozygotes in this group of patients have been detected without any error. HRM of short amplicons is a simple tool for effective, rapid, and reliable CYP2D6 genotyping that does not require real-time PCR, labeled probes, processing or any separations after PCR. The reaction is performed in a closed-tube system and is highly specific and sensitive. We proved that this technique is highly reliable for use in routine diagnostics. 相似文献
686.
Eva M. Egelseer Thomas Danhorn Magdalena Pleschberger Christoph Hotzy Uwe B. Sleytr Margit Sára 《Archives of microbiology》2001,177(1):70-80
The cell surface of Bacillus stearothermophilus ATCC 12980 is completely covered by an oblique lattice which consists of the S-layer protein SbsC. On SDS-polyacrylamide gels, the mature S-layer protein migrates as a single band with an apparent molecular mass of 122 kDa. During cultivation of B. stearothermophilus ATCC 12980 at 67 degrees C instead of 55 degrees C, a variant developed that had a secondary cell wall polymer identical to that of the wild-type strain, but it carried an S-layer glycoprotein that could be separated on SDS-polyacrylamide gels into four bands with apparent molecular masses of 92, 118, 150 and 175 kDa. After deglycosylation, only a single protein band with a molecular mass of 92 kDa remained. The complete nucleotide sequence encoding the protein moiety of this S-layer glycoprotein, termed SbsD, was established by PCR and inverse PCR. The sbsD gene of 2,709 bp is predicted to encode a protein of 96.2 kDa with a 30-amino-acid signal peptide. Within the 807 bp encoding the signal peptide and the N-terminal sequence (amino acids 31-269), different nucleotides for sbsD and sbsC were observed in 46 positions, but 70% of these mutations were silent, thus leading to a level of identity of 95% for the N-terminal parts. The level of identity of the remaining parts of SbsD and SbsC was below 10%, indicating that the lysine-, tyrosine- and arginine-rich N-terminal region in combination with a distinct type of secondary cell wall polymer remained conserved upon S-layer variation. The sbsD sequence encoding the mature S-layer protein cloned into the pET28a vector led to stable expression in Escherichia coli HMS174(DE3). This is the first example demonstrating that S-layer variation leads to the synthesis of an S-layer glycoprotein. 相似文献
687.
688.
T W Grunt C Somay A Ellinger M Pavelka E Dittrich C Dittrich 《Journal of cellular physiology》1992,151(1):13-22
We have compared the effects of N,N-dimethylformamide (DMF) and transforming growth factor (TGF)-beta 1 on the growth and phenotype of HOC-7 ovarian cancer cells. Previous density gradient fractionation of untreated HOC-7 cells suggested that rapidly growing small polygonal medium density cells revert spontaneously into less malignant flattened low density cells. Here we demonstrate that DMF and TGF-beta 1 induce similar flattened cell phenotypes. Both agents induce qualitatively similar alterations in the cells. DMF, however, exerted stronger effects than TGF-beta 1. The cells become flattened, develop cytoplasmic extensions, and reduce DNA-synthesis as well as anchorage-dependent and -independent growth. These effects are reversible after removal of the inducers, indicating that the cells have not become terminally differentiated. Electron microscopy demonstrates prominent filament bundles in treated cells. Immunofluorescence further shows that these cells contain large amounts of cytokeratin. Immunocytochemistry and ELISA demonstrate 1- to 5-fold higher amounts of desmoplakin and fibronectin after DMF- or TGF-beta 1-exposure. The described differentiation-like responses of HOC-7 cells can be used for recognition of pharmacologically induced maturation of ovarian cancer cells. 相似文献