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The influence of contact guidance on the orientation of colonies of subcultured vascular smooth muscle cells 总被引:1,自引:0,他引:1
Robert C. Buck 《In vitro cellular & developmental biology. Plant》1982,18(9):783-788
Summary Subcultures of smooth muscle cells derived from rat thoracic aorta were grown on plane plastic substrata and on plastic substrata
having ridges molded in them by a heated, ruled template. The cells were found to have a very high degree of contact guidance
when distributed sparsely on the ridged substrata. When the cell density increased multilayered, elongated colonies formed.
On plane substrata these were irregular, curved, and disposed in all directions. On the ridged substrata, however, the colonies
were straight, evenly spaced, and positioned at right angles to the ridges.
Supported by Grant MT1011 from the Medical Research Council of Canada. 相似文献
56.
Domestic pigeons were introduced into the Galapagos Islands in 1972 or 1973. There is a high prevalence of Trichomonas gallinae among them and some evidence of canker. Trichomonas gallinae can be found also in endemic Galapagos doves in the vicinity of Puerto Ayora on Santa Cruz Island. Doves examined on pigeon-free islands were not found infected. 相似文献
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Gary Wenk Robert Greenland 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1980,183(3):261-267
A procedure for the determination of norepinephrine and dopamine, based on high-performance liquid chromatography, is evaluated using an electrochemical detector system. The use of an inorganic mobile phase to provide resolution of low retention amines and extend column life is discussed. A high degree of correlation between estimations of endogenous catecholamine levels is reported using both electrochemical and fluorometric detector systems. Inter-assay reproducibility of the extraction method, and sensitivity and linearity of response of the electrochemical detector system are shown to be consistent across trials. The system described is determined to be accurate, sensitive, and reliable over time. 相似文献
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Ratul Saha Robert S. Donofrio Susan T. Bagley 《Journal of industrial microbiology & biotechnology》2010,37(8):843-848
A TaqMan quantitative real-time polymerase chain reaction (qPCR) assay was developed for the detection and enumeration of
three Pseudomonas species belonging to the mendocina sublineage (P. oleovorans, P. pseudoalcaligenes, and P. oleovorans subsp. lubricantis) found in contaminated metalworking fluids (MWFs). These microbes are the primary colonizers and serve as indicator organisms
of biodegradation of used MWFs. Molecular techniques such as qPCR are preferred for the detection of these microbes since
they grow poorly on typical growth media such as R2A agar and Pseudomonas isolation agar (PIA). Traditional culturing techniques not only underestimate the actual distribution of these bacteria but
are also time-consuming. The primer–probe pair developed from gyrase B (gyrB) sequences of the targeted bacteria was highly sensitive and specific for the three species. qPCR was performed with both
whole cell and genomic DNA to confirm the specificity and sensitivity of the assay. The sensitivity of the assay was 101 colony forming units (CFU)/ml for whole cell and 13.7 fg with genomic DNA. The primer–probe pair was successful in determining
concentrations from used MWF samples, indicating levels between 2.9 × 103 and 3.9 × 106 CFU/ml. In contrast, the total count of Pseudomonas sp. recovered on PIA was in the range of <1.0 × 101 to 1.4 × 105 CFU/ml for the same samples. Based on these results from the qPCR assay, the designed TaqMan primer–probe pair can be efficiently
used for rapid (within 2 h) determination of the distribution of these species of Pseudomonas in contaminated MWFs. 相似文献