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This paper intends to point out the possibility of using Internet photogrammetry to construct 3D models from the images obtained by means of UAVs (Unmanned Aerial Vehicles). The solutions may be useful for the inspection of ports as to the content of cargo, transport safety or the assessment of the technical infrastructure of port and quays. The solution can be a complement to measurements made by using laser scanning and traditional surveying methods. In this paper the authors recommend a solution useful for creating 3D models from images acquired by the UAV using non-metric images from digital cameras. The developed algorithms, created and presented software allows to generate 3D models through the Internet in two modes: anaglyph and display in shutter systems. The problem of 3D image generation in photogrammetry is solved by using epipolar images. The appropriate method was presented by Kreiling in 1976. However, it applies to photogrammetric images for which the internal orientation is known. In the case of digital images obtained with non-metric cameras it is required to use another solution based on the fundamental matrix concept, introduced by Luong in 1992. In order to determine the matrix which defines the relationship between left and right digital image it is required to have at least eight homologous points. To determine the solution it is necessary to use the SVD (singular value decomposition). By using the fundamental matrix the epipolar lines are determined, which makes the correct orientation of images making stereo pairs, possible. The appropriate mathematical bases and illustrations are included in the publication
The mutagenic activity of captan and captafol was tested using Ames stzaiiis and strains showing an SOS response. Captafol was mutagenic in S. typhimurium strain TA102 (uvr+) and captan in strain TA104 (uvrB). Both captan and captafol elicit damages in DNA recognized by correndonuclease U, as shown by the repair teat, and induced the SOS repair system in E. coli PQ37 (uvrA) strain. Only captafol induced the SOS system in PQ35 (uvr+). The lack of induction of p-galactesidaac at nonpermissive temperature in E. coli MD332 (dnaCs uvrA) strain showed that neither chemical was able to produce DNA breaks. In V79 Chinese hamster fibroblasts higher induction of c-mitosis by captafol than by captan (22% and 15% over th* control, respectively) was accompanied by a higher decrease in nonprotein sulfhydryl groups, mainly GSH (41% and 77%, respectively). The content of protein sulfhydryl groups was decreased by either fungicide to a similar extent.
In the recent paper genotoxic effects of daminozide and its metabolites were tested. Evaluation of the mutagenic effect of daminozide was by: (i) the Salmonella/mammalian microsome Ames test with S.typhimurium TA97, TA98, TA100 and TA102. (ii) E. coli PQ37 strain to reveal an induction of the SOS response, (iii) S. typhimurium TA1538 (uvrB) and TA1978 (uvr+) to detect the chemicals bound covalently to DNA (repair test). Daminozide was not mutagenic in any of the S.typhimurium strains and did not induce damages in DNA recognized by correndonuclease II, as shown by the repair test. Only metabolites of daminozide induced the SOS system.
The aim of the study was to evaluate the influence of a prolonged administration of two natural compounds – resveratrol (20 ppm) and protocatechuic acid (2000 ppm) – on the health status of Wistar rats. The animals were kept on supplemented diets for 7 and 24 weeks. Body weight was assessed weekly, and liver weight during autopsy. Liver morphology was evaluated histologically. The body weight in the 24th week, body weight gain (between the 1st and the 24th week of the experiment), and liver weight were significantly higher for the animals kept on the diet including resveratrol throughout the experiment than for those that had received this diet during the initial 7 weeks. However, differences in these parameters, as well as in the relative liver weight, between the control group and the groups exposed to both compounds were insignificant. Occasionally, mild, mostly reversible, microscopic hepatic changes (i.e., hydropic and fatty changes) were found, and these were slightly more common in the groups kept on supplemented diets. It seems that resveratrol and protocatechuic acid did not significantly disturb the wellness of rats, even after prolonged exposure.
The Chinese hamster cell mutant V-C8 is defective in the Brca2 gene (Kraakman-van der Zwet et al., 2002, Cell Biol.-, 22: 669). Here we report that V-C8 cells were 10-fold more sensitive to camptothecin, an inhibitor of topoisomerase I, than the parental V79 cells. The level of the relaxation activity of topoisomerase I in nuclear extracts was also lower (4-fold) in V-C8 than V79 cells, in spite of the fact that the level of the topoisomerase I protein was the same in these cells. The survival of V-C8 cells in the presence of camptothecin, the sensitivity of V-C8 topoisomerase I to camptothecin, and the level of the relaxation activity in V-C8 nuclear extract were almost completely restored by transfection of V-C8 cells with the murine Brca2 gene or by the transfer of human chromosome 13 providing the BRCA2 gene. These results indicate that the ob­served changes in the topoisomerase I activity in V-C8 are due to the defective func­tion of the Brca2 gene.
Constitutive (COX-1) and inducible (COX-2) cyclooxygenase isoforms have been detected in various mammalian tissues. Their activity is blocked by non-steroidal anti-inflammatory drugs that may induce various side reactions. The aim of the study was to evaluate the effects of DFU, a selective COX-2 inhibitor, on exocrine and endocrine pancreatic function and the immunoexpression of both COX isoforms in maternal and foetal rat pancreases. The compound was administered to pregnant Wistar rats once daily from the 8th to the 21st day of gestation. Glucose level and amylase activity were determined in the maternal sera. Maternal and foetal pancreases were examined histologically. Immunoexpression of COX-1 and COX-2 was also evaluated. Both biochemical parameters, as well as the histological structure of the pancreas were undisturbed in the dams and their foetuses. The maternal glucose level was found to be an important factor for foetal growth. Strong cytoplasmic COX-1 immunostaining was observed in acinar secretory cells, whereas in islets the immune reaction was weak. Endocrine cells also revealed strong cytoplasmic COX-2 staining in the maternal and foetal pancreases. Acinar cells exhibited nuclear reaction, which was strong in the foetal but weak in the maternal pancreases. No differences in COX immunoexpression were found between the DFU-exposed and the control groups in either mothers or foetuses. It should be stressed that DFU administered throughout mid and late pregnancy in rats did not change maternal or foetal pancreatic morphology or immunoexpression of either of the main COX isoforms in the organ.
Joint formation is a developmental process regulated by various factors including bone morphogenetic proteins, transforming and growth factors, etc. Recently, a high expression of cyclooxygenase (COX) isoforms in the foetal cartilaginous elements was also revealed. On the other hand, various joint and skeletal abnormalities were seen in laboratory animal and human offspring, exposed in utero to several COX inhibitors. Immunoexpression of constitutive (COX-1) and inducible (COX-2) cyclooxygenase isoforms was evaluated in various articular structures of untreated and unfamiliar 21-day-old male rat foetuses. Both COX isoforms were detected in the articular cartilage and joint capsule, as well as in the intra-articular disc of the temporomandibular joint and meniscus of the knee joint. COX-1 immunostaining was revealed in the anterior and posterior cruciate ligament of the knee joint and the labrum of the hip and shoulder, whereas COX-2 immunoreactivity in those structures was not found. It could be concluded that both constitutive and inducible COX isoforms are physiologically expressed in various structures of synovial joints in rat foetuses at the end of prenatal development. (Folia Morphol 2009; 68, 2: 59–64)
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