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61.
Uwe Karsten Gisela Papsdorf Annedore Pauly Borivoj Vojtesek Roland Moll E. Birgitte Lane Henrik Clausen Peter Stosiek Michael Kasper 《Differentiation; research in biological diversity》1993,54(1):55-66
Abstract. Normal (non-transformed) human mammary epithelial cell lines derived from reduction mammoplasties were analyzed by immunocytochemistry with more than 80 monoclonal antibodies (mAbs) and other specific reagents to tissue-specific and developmentally regulated antigens at different passage levels. A subpopulation of poorly differentiated, proliferating epithelial cells, corresponding to the 'selected' cell type of late passages, is shown to be characterized by a new marker, the histo-blood group antigen H type 2, probably carried on a membrane-bound glycolipid. These cells also express a number of other onco-developmental carbohydrate antigens [Ley , Lex , sialosyl-Lea , precursor of Thomsen Friedenreich antigen (Tn ), but not Thomsen-Friedenreich antigen and sialosyl-Tn ]. Their cytokeratin (CK) phenotype, as assessed by reactivity with monospecific mAbs and two-dimensional gel electrophoresis, is CK 5, 6, 14 and 17, with CK 19 being consistently absent, and varying minor amounts of CK 7, 8 and 18, as well as 15 and 16. The reactivity of these cells with a panel of 11 mAbs specific for CK 18 varies considerably even after cloning, indicating heterogeneity of epitope expression or accessibility. Our data strongly suggest that the H type 2+ cells develop from the basal cell layer of the mammary gland. 相似文献
62.
Bente R. Jensen Bente Schibye Karen S?gaard Erik B. Simonsen Gisela Sj?gaard 《European journal of applied physiology and occupational physiology》1993,67(5):467-475
Physiological responses to physical work were assessed for 29 female industrial sewing-machine operators during an 8-h working day under ordinary working conditions. During sewing-machine work, the average (left and right) static load in the trapezius muscle was 9% of the maximal electromyogram (EMG) amplitude (% EMGmax), while the average mean load was 15% EMGmax, and the average peak load was 23% EMGmax. The static load level was unrelated to the muscle strength of the sewing-machine operators, which for the group as a whole was within the normal range. The load levels remained unchanged during the working day, while changes in the EMG mean power frequency and zero crossing frequency rate occurred, both indicating the development of muscle fatigue in left and right trapezius muscle during the working day. In line with this, the rating of perceived exertion in the shoulder and neck region increased during. the working day. Dividing the group of sewing-machine operators into two groups, those with the highest frequency and those with the lowest frequency of shoulder/neck troubles showed that the former group had significantly lower muscle strength, despite the fact that no differences in the surface EMG during sewing were found between the two groups. It was concluded that industrial sewing-machine work involves a pattern of shoulder muscle activity which induces fatiguing processes in the shoulder and neck regions. Furthermore, since the static shoulder muscle load was independent of muscle strength, factors other than working posture may be of significance for the static shoulder muscle load. 相似文献
63.
Gisela M. Figueiredo Hermógenes F. Leitão-Filho Alpina Begossi 《Human ecology: an interdisciplinary journal》1993,21(4):419-430
Local plants are a very important resource for the community of Gamboa, located at Itacuruçá Island, Sepetiba Bay, State of Rio de Janeiro, Brazil Ninety species of plants, belonging to 40 families, are used for a variety of purposes, such as food, construction, handicraft, and medicine. In a survey medicinal uses for plants were the most quoted by the community. Uses of medicinal plants within Gamboa and with other coastal communities are analyzed using diversity indices. Use by different categories of people based on sex, age, and economic activity was compared and significant differences were found among the groups compared, except for economic categories (fishermen and non-fishermen). The theory of island biogeography is shown to be useful for analyzing different levels of resource uses on different islands. 相似文献
64.
Michael Neubeck Elmar Prenner Predrag Horvat Rudolfo Bona Albin Hermetter Anton Moser 《Archives of microbiology》1993,160(2):101-107
The bacterial secretion of glutamate was studied through plasma membrane fluidity, measured by anisotropy using the fluorophore TMA-DPH incorporated in the lipid part of the cell membrane. Cells of Brevibacterium sp. ATCC 13869 (wild type) were switched from the biotin-limited, producing state to the biotin-supplemented, non-producing state, and back. The following conclusions could be drawn: 1. It was not possible to detect any change in anisotropy by switching the cells from biotin-limited biotin-supplemented, as well as from biotin-supplemented, to biotin-limited, media. 2. The anisotropy value in the glutamic acid fermentation remains constant during the lag, exponential, growth, production and stationary phases. 3. The treatment of cells with a neutral synthetic polyester of ethylene-and propyleneoxide with soya oil-fatty acids increased the anisotropy values, indicating incorporation of the surfactant. 4. Glutamate secretion is not coupled with membrane fluidity, so a leak providing a general fluidization of the membrane could not be detected. 相似文献
65.
Amanda dos Santos Marina Tenório Botelho Willian Reina Joviano Vicente Gomes José Roberto Machado Cunha da Silva Gisela de Aragão Umbuzeiro 《Invertebrate Biology》2023,142(1):e12394
Hemocytes are circulating blood cells that play a crucial function in amphipods and other crustacean immune systems. The hemocytes of the marine tropical amphipod Parhyale hawaiensis have been used for the evaluation of DNA damage and micronuclei, but they have not been characterized in the scientific literature. The aim of this study was to describe the hemolymph cells of P. hawaiensis and study their phagocytotic activity. Basic dyes were used to differentiate the cell types and the presence of lipids. The total hemocyte counts (THCs) and the proportion and sizes of the hemocyte types were determined. Hemolymph was exposed to Escherichia coli for verification of the presence of phagocytosis. Three cell types, all containing lipids, were identified in P. hawaiensis: granulocytes (oval shape, 13.4 × 7.6 μm), semi-granulocytes (oval shape, 14.1 × 7.2 μm), and hyalinocytes (round shape, 9.6 × 7.2 μm). Those three cell types were found in different percentages in males (64.8%, 31.1%, and 4.2%) and females (70.1%, 28.2%, and 1.7%). THCs for males were 9007 ± 3800 cells per individual and 4695 ± 1892 cells per individual for females. The cells of E. coli were phagocytized by the hemocytes. Our findings increased the knowledge of hemocytes in P. hawaiensis and is a step forward in using hemocyte-based immune responses as an endpoint in ecotoxicology. 相似文献
66.
Martine de Boer Maaike te Lintel Hekkert Jiang Chang Bibi S. van Thiel Leonie Martens Maxime M. Bos Marion G. J. de Kleijnen Yanto Ridwan Yanti Octavia Elza D. van Deel Lau A. Blonden Renata M. C. Brandt Sander Barnhoorn Paula K. Bautista-Niño Ilona Krabbendam-Peters Rianne Wolswinkel Banafsheh Arshi Mohsen Ghanbari Christian Kupatt Leon J. de Windt A. H. Jan Danser Ingrid van der Pluijm Carol Ann Remme Monika Stoll Joris Pothof Anton J. M. Roks Maryam Kavousi Jeroen Essers Jolanda van der Velden Jan H. J. Hoeijmakers Dirk J. Duncker 《Aging cell》2023,22(3):e13768
67.
In a study with rats it was determined whether dietary magnesium concentration affects plasma esterase activities. The feeding of a diet with 0.01% (w/w) instead of 0.04% magnesium reduced plasma magnesium concentration by 50%. Plasma total esterase, arylesterase and butyrylcholinesterase activities were significantly decreased in the magnesium-deficient rats. In rats fed a diet containing 0.02% magnesium, plasma magnesium concentration was lowered by 30%, and group mean plasma total esterase activity was decreased, but not the activities of arylesterase and butyrylcholinesterase. 相似文献
68.
Gisela Mosig 《Molecular & general genetics : MGG》1962,93(2):280-286
Zusammenfassung In Massenlysaten und Einzelwürfen vonT 4-Kreuzungen steigt der Prozentsatz der Rekombinanten mit steigender Infektionsmultiplizität an, und zwar sowohl zwischen gekoppelten als auch zwischen ungekoppelten Genen. Dieser Befund stimmt mitTrautners (1960) Ergebnissen beiT 1-Kreuzungen überein. Der scheinbarte Widerspruch zuEpsteins (1958) früheren Resultaten beiT 4-Kreuzungen läßt sich erklären, da verschiedene Wirtsbakterien verwendet wurden.Es wird diskutiert, ob dieser Effekt durch die Annahme erklärt werden kann, daß die infizierenden Phagegenome bei der Rekombination brechen und daß die Bruchstellen zufallsgemäß über die Genome einer Phagenpopulation verteilt sind. Die beschriebenen Versuche schließen jedochTrautners Interpretation nicht aus, daß in der infizierten Bakterienzelle eine Topographie existiert, d. h., daß die verschiedenen Genotypen während der Vermehrung nach Einzelinfektion nicht so vollständig durchmischt werden wie nach Mehrfachinfektion.
With 2 Figures in the Text 相似文献
With 2 Figures in the Text 相似文献
69.
Shau-Ting Chiu Lori H. Anton Frank W. Ewers Raymond Hammerschmidt Kurt S. Pregitzer 《American journal of botany》1992,79(2):149-154
Fertilized stands of Pseudotsuga menziesii were found to have glaucous needles. We investigated the morphological and quantitative characteristics of the epicuticular waxes of needles of fertilized and control trees. Glaucousness was caused by ornate tubular epicuticular wax. Dipping needles in chloroform, which dissolves waxes, eliminated the glaucous appearance. Based on cryostage scanning electron microscopic observations, the epicuticular waxes in the nonstomatal region were much more ornate on the needles of the fertilized trees (experimental needles) than in unfertilized trees (control needles). The stomatal region in both experimental and control needles showed similarly ornate waxes. Quantities of waxes were similar in experimental and control needles. The glaucousness was not the result of greater quantities of wax; rather, fertilization altered wax morphology in the nonstomatal regions. 相似文献
70.
Anton Hofreiter 《Nordic Journal of Botany》2004,24(2):117-141
The subgenus Sphaerine of Bomarea (Alstroemeriaceae) recently contains 33 validly published names. Extended field studies in Peru and extensive investigation of herbarium material revealed the urgent necessity for a revision. As a result, the number of species is reduced to 12, among them two species are newly described. 9 species are members of an other subgenus. A key to determine the species is given in English and Spanish. The typical growth form and its variability, habitat preferences and distribution are discussed separately for each species. 相似文献