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TM Sugihara I Bach C Kioussi MG Rosenfeld B Andersen 《Canadian Metallurgical Quarterly》1998,95(26):15418-15423
Nuclear LIM domains interact with a family of coregulators referred to as Clim/Ldb/Nli. Although one family member, Clim-2/Ldb-1/Nli, is highly expressed in epidermal keratinocytes, no nuclear LIM domain factor is known to be expressed in epidermis. Therefore, we used the conserved LIM-interaction domain of Clim coregulators to screen for LIM domain factors in adult and embryonic mouse skin expression libraries and isolated a factor that is highly homologous to the previously described LIM-only proteins LMO-1, -2, and -3. This factor, referred to as LMO-4, is expressed in overlapping manner with Clim-2 in epidermis and in several other regions, including epithelial cells of the gastrointestinal, respiratory and genitourinary tracts, developing cartilage, pituitary gland, and discrete regions of the central and peripheral nervous system. Like LMO-2, LMO-4 interacts strongly with Clim factors via its LIM domain. Because LMO/Clim complexes are thought to regulate gene expression by associating with DNA-binding proteins, we used LMO-4 as a bait to screen for such DNA-binding proteins in epidermis and isolated the mouse homologue of Drosophila Deformed epidermal autoregulatory factor 1 (DEAF-1), a DNA-binding protein that interacts with regulatory sequences first described in the Deformed epidermal autoregulatory element. The interaction between LMO-4 and mouse DEAF-1 maps to a proline-rich C-terminal domain of mouse DEAF-1, distinct from the helix-loop-helix and GATA domains previously shown to interact with LMOs, thus defining an additional LIM-interacting domain. 相似文献
44.
ME Rosenfeld M Feng SI Michael GP Siegal RD Alvarez DT Curiel 《Canadian Metallurgical Quarterly》1995,1(12):1571-1580
One strategy used for gene therapy of cancer is molecular chemotherapy. This approach is based on selective expression of an encoded toxin in cancer cells to achieve their eradication. One potential advantage of this strategy derives from a phenomenon, termed the bystander effect, whereby only a fraction of cells needs to be transduced to eradicate a tumor population. Despite the theoretical advantages of this phenomenon, it has only been described in a few cellular targets. Therefore, we undertook strategies to develop a molecular chemotherapy approach for ovarian carcinoma utilizing the herpes simplex virus thymidine kinase (HSV-TK) gene. Initially, we established that human ovarian carcinoma cell lines could be transduced at high efficiency with adenoviral vectors encoding reporter genes. We next determined that the human ovarian cell line SKOV3 could exhibit bystander killing by stably transducing it to express HSV-TK and performing cell mixing experiments with varying percentages of HSV-TK-expressing and HSV-TK-nonexpressing cells. Based on these findings, we constructed a recombinant adenovirus encoding HSV-TK and utilized it to induce human ovarian carcinoma cell lines to the sensitizing effects of ganciclovir. In addition, primary cultures of ovarian carcinoma cells were found to be highly transducible with recombinant adenoviral vectors and could be induced to the sensitizing effects of ganciclovir after induction of HSV-TK expression by the adenoviral vector. These studies indicate that molecular chemotherapy using a recombinant adenoviral vector expressing HSV-TK may provide a rational strategy for human ovarian carcinoma. 相似文献
45.
A sample of 42 case notes of alcoholic patients were abstracted for 17 items by three different raters. Interrater agreement was generally rather low. Research based on case-note abstraction which does not report on abstraction reliabilities must therefore be viewed with some suspicion. It would be helpful if clinical material could more often be collected in a standardized manner. 相似文献
46.
A general-purpose scene-analysis system is described which uses constraint-filtering techniques to apply domain knowledge in the interpretation of the regions extracted from a segmented image. An example is given of the configuration of the system for a particular domain, FLIR (Forward Looking InfraRed) images, as well as results of the system's performance on some typical images from this domain. A number of improvements to these techniques are proposed. 相似文献
47.
The laminar and incompressible flow in a straight cascade is investigated. Numerical solutions of the full Navier-Stokes equations are obtained using the vorticity-stream function formulation and body fitted coordinate system. The numerical method includes a special force balance for the determination of the downstream boundary condition and a double sweep deferred correction which allows a second order accuracy but with the stability properties of an upwind first order scheme. Results for cylindrical, elliptical and NACA 0012 airfoils are presented including separated flow regions. Good agreement with experiments and previous computations is obtained. 相似文献
48.
This paper describes methods of segmenting electron micrographs of rock cross-sections into “pores” and “grains”. Pores are extracted by a thresholding-based scheme. Grain extraction is more difficult, since the grains are packed together. A multiresolution technique is used to link the edges and cracks surrounding the grains so as to separate the non-pore regions into individual grains. 相似文献
49.
Robert M. Haralick Larry S. Davis Azriel Rosenfeld David L. Milgram 《Information Sciences》1978,14(3):199-219
The problem of labeling a set of units in such a way as to satisfy an order-N compatibility relation is discussed and shown to be NP-complete. Some general procedures for reducing size of the compatibility relation are defined, properties of these procedures are derived, and their incorporation into a backtracking process is discussed. Their computational cost and storage requirements are also considered. 相似文献
50.
Azriel Rosenfeld 《Pattern recognition letters》1984,2(5):311-317
In pattern recognition we often want to measure geometric properties of regions in an image, but these regions are not always ‘crisply’ defined; it is sometimes more appropriate to regard them as fuzzy subsets of the image. Many of the basic geometric properties of and relationships among regions can be generalized to fuzzy sets; these include connectedness, adjacency and surroundedness, starshapedness and convexity, area and perimeter, extent and diameter. This paper summarizes past work on such fuzzy geometric concepts, and also includes some new results. 相似文献