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131.
Mouse submandibular epithelial cells can be grown in primary culture using the collagen gel matrix and a chemically defined medium consisting of insulin, transferrin, cholera toxin, and BSA (or FGF). Sustained cell growth leading to a 5–10-fold increase in cell number was observed in less than 2 weeks. In the presence of these additives, clumps of cells proliferate by extending ‘star-like’ projections into the matrix, resulting in three-dimensional outgrowths. The morphology of these outgrowths can be modulated to form a ‘cyst-like’ appearance by deleting BSA and adding cortisol to the basal medium containing insulin, transferrin, cholera toxin and FGF. In brief, a serum-free medium for sustained growth has been devised and a simple manipulation of supplements can modulate the three-dimensional colony morphology in the collagen gel matrix. Finally, the resulting outgrowths can produce epidermal growth factor (EGF) in response to dihydrotestosterone. 相似文献
132.
133.
Jason Yang Raphael Guzman James Richards S. Nandi 《In vitro cellular & developmental biology. Plant》1980,16(6):502-506
Summary Mammary tumor epithelial cells from BALB/cfC3H mice were dispersely embedded inside the collagen gels in Ham's F-12 medium
containing horse serum. A sustained cell growth leading to a 5- to 10-fold increase in cell number over initial level was
observed in less than 2 weeks. The extent of this growth was found to be dependent on serum concentration. However, addition
of various protein and steroid hormones, both singly and in combination, to low-serum-containing medium failed to achieve
a comparable level of growth to that promoted by higher serum concentration. Mammary tumor cells can now be consistently propagated
in primary culture.
This investigation was supported by Grants CA05388 and CA09041 awarded by the National Cancer Institute, Department of Health,
Education and Welfare, and by cancer research funds of the University of California. 相似文献
134.
Comparative ultrastructure of Mycobacterium leprae and Mycobacterium lepraemurium cell envelopes. 下载免费PDF全文
H T Nguyen D D Trach N V Man T H Ngoan I Dunia M A Ludosky-Diawara E L Benedetti 《Journal of bacteriology》1979,138(2):552-558
The structural properties of the cell envelopes of Mycobacterium leprae and Mycobacterium lepraemurium were investigated by freeze-fracture, freeze-etching, and negative-staining techniques. Freeze-fracture split the cell wall and exposed the internal features of the peptidoglycolipid mycosidic filamentous network. The cell membrane was also split into two asymmetric faces. The external fracture face was characterized by linear arrays of intramembranous particles, whereas the protoplasmic fracture face showed randomly distributed clusters of particulate entities. Comparative analysis of the ultrastructural features observed in M. leprae and M. lepraemurium indicated that the organization of the cell envelope in these two species differed particularly with respect to the amount and complexity of the superficial peptidoglycolipid and mycosidic integument, which is poorly developed in the mycobacterium responsible for human disease. 相似文献
135.
Size of the pool of alveolar neutrophils in normal rabbit lungs 总被引:3,自引:0,他引:3
Cohen A. B.; Batra G.; Petersen R.; Podany J.; Nguyen D. 《Journal of applied physiology》1979,47(2):440-444
136.
In order to correlate and compare the antigenic relationships observed between nine yeast strains, we have studied their major antigenic determinant represented by the mannans. This material is a constituent of their cell.The compounds that we have isolated are, in reality, glycopeptides. All their polysaccharide fractions consist of mannose only — except for those of the compounds that we have isolated of R. glutinis and C. lipolytica. All these polysaccharides have very close ramified structures; the only one that seems to be very different is that of R. glutinis, and this is in agreement with the antigenic properties of that yeast.The peptidic fractions of these glycopeptides are rich in threonine, serine and aspartic acid and it is very likely that these amino acids make the link with the polysaccharide fraction. The quantity of these amino acids seem to be affected by the conditions of culture of the yeasts, but not their presence or absence. 相似文献
137.
Ashwani Kumar Galina Aglyamova Yun
Young Yim Aaron O Bailey Haley
M Lynch Reid
T Powell Nghi
D Nguyen Zachary Rosenthal Wen-Ning Zhao Yi Li Jianping Chen Shanghua Fan Hubert Lee William
K Russell Clifford Stephan Alfred
J Robison Stephen
J Haggarty Eric
J Nestler Jia Zhou Mischa Machius Gabby Rudenko 《Nucleic acids research》2022,50(16):9548
138.
139.
140.
越南铁线莲属一新种 总被引:3,自引:0,他引:3
Nguyen Yhi DO 《植物分类学报》2006,44(5):595-597
本文描述的产于越南的毛茛科Ranunculaceae铁线莲属Clematis一新种C. hagiangensis N. T. Do是欧亚大陆第一个具单性花的种, 在花构造方面与单性铁线莲组单性铁线莲亚组sect. Aspidanthera Spach subsect. Dioicae (Prantl) W. T. Wang的种类近缘, 但叶均为单叶, 萼片呈卵形或宽卵形而不同。在单性铁线莲亚组的种, 叶通常为复叶, 只在C. dimorphophylla W. T. Wang和C. variifolia W. T. Wang同时为单叶和复叶, 此外萼片呈长圆形、倒披针形或狭卵形。 相似文献