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151.
Recent studies have shown that fibroblast growth factors (FGF) play an important role in the diverse cellular mechanisms involved with vertebrate development. One system which has received a great deal of attention is the developing limb in part because of the extensive epithelial-mesenchymal interactions that take place during this process. Because it closely parallels the developmental process of the limb and is a model for wound repair, the phenomenon of amphibian limb regeneration has been used to investigate the role of FGF in these processes. We have recently reported on the cloning and functional characterization of an FGF receptor (FGFR) isolated from amphibian regenerative tissue. In this report, we describe the isolation and characterization of an FGF-1 molecule from the newt, Notophthalmus viridescens. Amino acid sequence comparisons indicate that the newt FGF-1 exhibits between 79 to 83% identity with FGF-1 from mammalian and avian species. The full length cDNA of the newt FGF-1 was cloned into a prokaryotic expression vector and purified from E. coli. Although the newt FGF-1 shares a high degree of primary amino acid sequence similarity with other FGF-1 molecules, the recombinant protein was not detected in a Western blot analysis using a polyclonal antibody directed against mammalian FGF-1. Despite the antigenic divergence, the newt FGF-1 was capable of binding to NIH/3T3 and Chinese hamster ovary cells overexpressing mammalian and amphibian FGFRs with dissociation constants comparable to those reported for mammalian FGF-1. Newt FGF-1 could also be cross-linked to receptors on the surface of NIH/3T3 cells. In addition, it elicits a mitogenic response in NIH/3T3 cells indistinguishable from human recombinant FGF-1. 相似文献
152.
SG Zubova AO Danilov VB Okulov DF Kiagulov II Stiuf AI Zaritski? 《Canadian Metallurgical Quarterly》1996,42(5):80-85
It has been established that once macrophages become activated, they pass through different stages of functional activity. Mouse macrophages activated by BCG "exerted" pronounced cytotoxic effects for 2-5 days to be followed later by growth-stimulating ones. However, in other experiments, the cytotoxic effect was either absent or occurred at later stages which was probably due to a certain functional state of macrophages before activation. The synthesis of TGF-beta increased 1-2 days after activation with BCG vaccine, lipopolysacharide and gamma radiation. An increase in mRNA TGF-beta i expression was observed only 5 days after activation of macrophages. 相似文献
153.
154.
A computational, three-dimensional coupled fluid-structure dynamics model was developed for a generic pericardial aortic valve in a rigid aortic root graft with physiologic sinuses. Valve geometry was based on that of the natural valve. Blood flow was modeled as pulsatile, laminar, Newtonian, incompressible flow. The structural model accounted for material and geometric nonlinearities and also simulated leaflet coaptation. A body fitted grid was used to subdivide the flow domain into computational finite volume cells. Shell finite elements were used to discretize the leaflet volume. A finite volume computational fluid dynamics code and finite element structure dynamics code were used to solve the flow and structure equations, respectively. The fluid flow and structural equations were coupled using an implicit "influence coefficient" technique. Physiologic ventricular and aortic pressure waveforms were prescribed as the flow boundary conditions. The aortic flow field, valve structural configuration, and leaflet stresses were computed at 2 msec intervals. Model predictions on aortic flow and transient variation in valve orifice area were in close agreement with corresponding experimental in vitro data. These findings suggest that the computer model has potential for being a powerful design tool for bioprosthetic aortic valves. 相似文献
155.
SG Zubova F Crechet N Gault AO Danilov MK Vozenin JL Lefaix F Daburon M Martin VB Okulov 《Canadian Metallurgical Quarterly》1998,126(11):529-533
We report on papers concerning in topic "Diseases of the breast", which were published in the Zentralblatt für Gyn?kologie during the first half of the 20th century. Only 26 publications about senologic problems were found in 44 years. Papers about the mammary theory of eclampsia, mastitis, plastic operations and breast cancer are reported. 相似文献
156.
AV Vartanov VB Polianski? EN Sokolov DV Evtikhin 《Canadian Metallurgical Quarterly》1998,48(5):788-796
Color vision of three protanomal subjects was studied by means of direct paired comparison technique using 25 colors with different brightness. It was shown that the characteristics of their color vision could be completely and adequately described in the frames of the four-dimensional spherical model of color perception. The spatial axes could be identified as the two color-opponent mechanisms (red-green and blue-yellow) and the two achromatic mechanisms (brightness and darkness). Deformation of the color axes in protanomals (as compared with the normal trichromatics) was demonstrated in the "red" and "yellow" spectral region. The visual disturbance in protanomal subjects involves not only color but also achromatic mechanisms. This is manifested in the a deformation of perceptual brightness scale. In comparison with normal trichromatic subjects, the protanomals perceive the red and adjacent colors as achromatic while green, yellow-green, and orange as more bright but low-saturated colors. 相似文献
157.
This investigation utilized the recent technology for the assessment of creativity to examine the association between problem solving and suicide ideation. Three kinds of problem-finding and -solving tasks were administered to 81 (nonclinical) college students. One of these tasks assesses "problem generation" and was expected to be particularly informative, given that individuals considering suicide may perceive many problems but find few solutions. Results supported this expectation: Problem generation scores were significantly correlated with suicide ideation, even after stress was statistically controlled. A secondary analysis suggested that the originality and flexibility of solutions may be influenced by the particular problem an individual faces. 相似文献
158.
The results of experimental and clinical studied of the suture material "Caproiod" are presented. The advantage of the material suggested is its favourable effect on regenerative processes in the region of suture and anastomoses which resulted in their increased hermeticity. Use of "Caproiod" permits to prevent the development of postoperative complications caused by a quality of the suture material. 相似文献
159.
For each of the years 1991-1994 400, 209, 170 and 133 open common bile duct stone extraction were performed in Denmark, corresponding to 35%, 17%, 12% and 5% respectively of patients diagnosed with common bile duct stone. There was only little variation between the 16 hospital counties. The expected decrease in open common bile duct surgery corresponds to the introduction of several non-invasive methods for the treatment of common bile duct stones. To achieve further reduction in open surgery, centralization of the treatment of common bile duct stones is necessary. 相似文献
160.
HB Coutinho TI Robalinho VB Coutinho JR Almeida JT Filho G King D Jenkins Y Mahida HF Sewell D Wakelin 《Canadian Metallurgical Quarterly》1996,49(9):717-720
AIM: To investigate the immunopathological changes in duodenal tissues induced by strongyloidiasis and to relate these to degrees of clinical severity. METHODS: Tissues taken from 21 patients showing mild, moderate or severe symptoms of strongyloidiasis, and from non-infected controls, were sectioned and stained immunocytochemically for IgA, secretory component (SC) and HLA-DR. Immunopathology was assessed by changes in numbers, intensity and distribution of stained cells. RESULTS: Parasitised individuals showed villous atrophy and crypt hyperplasia. There was notable infiltration of the lamina propria by IgA positive plasma cells and of the epithelium by intraepithelial lymphocytes. Infection was also associated with increased expression of SC and decreased expression of HLA-DR in epithelial cells. Changes in all parameters correlated with degree of clinical severity. CONCLUSIONS: Profound mucosal changes are induced by strongyloidiasis. Some are analogous to those seen in coeliac disease, but others seem quite unusual. It is likely that these changes are functionally related to the immunopathophysiological consequences of infection seen in patients with severe disease. 相似文献