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101.
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Tanasic I Milic-Lemic A Tihacek-Sojic L Stancic I Mitrovic N 《Biomechanics and modeling in mechanobiology》2012,11(6):751-758
It was the purpose of this study to determine and analyse strains in the bone of posterior mandible below the removable and fixed partial dentures using Digital Image Correlation Method. Dried mandible with shortened dental arch (Kennedy Class 1) was used in the experiment. The mandible model was prepared for accepting two types of restorations for bilaterally missing molars conventional therapy, and removable and fixed partial dentures were manufactured following standard prosthetic protocol. The models with prosthetic restorations placed in situ were subjected to loading of 50-300 N, and photographed using two digital cameras as part of the digital image correlation method equipment. Afterwards, the obtained data for strains within restored mandible during loading ciclus were analysed in the software Aramis and graphically presented. Percentage size of the mandible strains within the line section are from 0.14 to 0.19% for the removable partial denture experimental model and 0-0.14% for the fixed partial denture experimental model. The study has demonstrated that Digital Image Correlation method can be used to measure strain on the mandible surface and replacements during loading and that from biomechanical perspective both therapeutic modalities can be equally useful for the restoration of the mandible with bilaterally distal edentulous spaces. 相似文献
103.
Irena Kruk Teresa Piechowska Paweł Berczyński Aleksandra Kładna Oya Bozdağ‐Dündar Meltem Ceylan‐Unlusoy Hassan Y. Aboul‐Enein 《Luminescence》2015,30(5):556-563
Fifteen chromonylrhodamine derivatives (CRs) were synthesized and the antioxidant activity levels were evaluated for the first time. The antioxidant activity potencies of these chromone derivatives were evaluated towards superoxide anion radicals, hydroxyl radicals and 2,2‐diphenyl‐1‐picrylhydrazyl radicals. Also, the total antioxidant capacity of the tested compounds was measured using the ferric‐ferrozine assay. The antioxidant activities were investigated using a chemiluminescence (CL) assay, spectrophotometry measurements, direct electron paramagnetic resonance (EPR) and the EPR spin‐trapping technique. The 5,5‐dimethyl‐ 1‐pyrroline‐1‐oxide (DMPO) was applied as spin trap. Eleven of the 15 chromone compounds exhibited a decrease in the CL accompanying the superoxide anion radical produced in anhydrous dimethylsulfoxide (DMSO), ranging from 71–94% at concentration of 1 mmol /L; four of these compounds enhanced light emission in the range 231–672%. Similarly, these compounds caused 28–58% inhibition in the intensity of the DMPO‐OOH radical EPR signal and the DMPO‐OH radical (from 12–48%). Furthermore, three of these compounds showed very good antioxidant response towards the DPPH radical (EC50: 0.51–0.56 µmol/L) and the high reduction potentials. These findings demonstrate that the chromone compounds tested may be considered as effective free radicals scavengers, a finding that is of great pharmacological importance. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Milutin Miri Aleksandra Mikovi Sran Brki Jovan Vasiljevi Nenad Keserovi Milan Pei 《FEMS immunology and medical microbiology》1994,10(1):65-74
Abstract The randomized clinical trial with interferon-α (IFN) or thymic hormones versus conventional therapy was conducted in patients with myocarditis and idiopathic dilated cardiomyopathy (IDC). We enrolled 180 patients to receive IFN (3–5 million units per day) for 3 months, thymomodulin (10 mg three times per week) for 2 months, or conventional therapy alone. Patients were followed-up for 7 years after the end of treatment. Left ventricular function, exercise tolerance and survival rate were significantly better at long-term follow-up in patients treated with IFN or thymomodulin, than in conventionally treated patients. These results implicate that immune modulating therapy might represent important contribution in the treatment of myocarditis and IDC. 相似文献
106.
Lidija Simova Carolyn Williams Georgi D. Efremov Aleksandra Gordova-Muratovska Stojka Suštić Eila K. Watson Robert Williamson 《Human genetics》1990,85(4):432-433
Summary Chromosomes from 19 unrelated Southern Yugoslav families in which cystic fibrosis (CF) occurs were analysed for the presence
of the ΔF508 mutation, using polymerase chain reaction amplification followed by dot blot and polyacrylamide gel analysis.
Of the 38 CF chromosomes, 15 (39.5%) carry the ΔF508 deletion. Restriction fragment length polymorphism haplotypes for KM19/PstI, XV2c/TaqI and J3.11/PstI marker loci were determined and are compared for a total of 34 N and 37 CF chromosomes. 相似文献
107.
Aleksandra Kwiatkowska Jacek Zebrowski Bernadetta Oklejewicz Justyna Czarnik Joanna Halibart-Puzio Maciej Wnuk 《Biochemical and biophysical research communications》2014
Plant cell suspension cultures represent good model systems applicable for both basic research and biotechnological purposes. Nevertheless, it is widely known that a prolonged in vitro cultivation of plant cells is associated with genetic and epigenetic instabilities, which may limit the usefulness of plant lines. In this study, the age-dependent epigenetic and physiological changes in an asynchronous Arabidopsis T87 cell culture were examined. A prolonged cultivation period was found to be correlated with a decrease in the proliferation rate and a simultaneous increase in the expression of senescence-associated genes, indicating that the aging process started at the late growth phase of the culture. In addition, increases in the heterochromatin-specific epigenetic markers, i.e., global DNA methylation, H3K9 dimethylation, and H3K27 trimethylation, were observed, suggesting the onset of chromatin condensation, a hallmark of the early stages of plant senescence. Although the number of live cells decreased with an increase in the age of the culture, the remaining viable cells retained a high potential to efficiently perform photosynthesis and did not exhibit any symptoms of photosystem II damage. 相似文献
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Trojan LA Kopinski P Wei MX Ly A Glogowska A Czarny J Shevelev A Przewlocki R Henin D Trojan J 《Acta biochimica Polonica》2002,49(4):979-990
Alterations in the expression of growth factors and their receptors are associated with the growth and development of human tumors. One such growth factor is IGF-I (insulin-like growth factor I ), a 70-amino-acid polypeptide expressed in many tissues, including brain. IGF-I is also expressed at high levels in some nervous system-derived tumors, especially in glioblastoma. When using IGF-I as a diagnostic marker, 17 different tumors are considered as expressing the IGF-I gene. Malignant glioma, the most common human brain cancer, is usually fatal. Average survival is less than one year. Our strategy of gene therapy for the treatment of gliomas and other solid tumors is based on: 1) diagnostic using IGF-I gene expression as a differential marker, and 2) application of "triple-helix anti-IGF-I" therapy. In the latter approach, tumor cells are transfected with a vector, which encodes an oligoribonucleotide--an RNA strand containing oligopurine sequence which might be capable of forming a triple helix with an oligopurine and/or oligopyrimidine sequence of the promotor of IGF-I gene (RNA-IGF-I DNA triple helix). Human tumor cells transfected in vitro become down-regulated in the production of IGF-I and present immunogenic (MHC-I and B7 expression) and apoptotic characteristics. Similar results were obtained when IGF-I antisense strategy was applied. In both strategies the transfected cells reimplanted in vivo lose tumorigenicity and elicit tumor specific immunity which leads to elimination of established tumors. 相似文献
110.
Soft songs in male ortolan buntings are used in an aggressive context but are not an aggressive signal 下载免费PDF全文
Aleksandra Jakubowska Tomasz S. Osiejuk 《Ethology : formerly Zeitschrift fur Tierpsychologie》2018,124(8):549-558
Many bird species produce low‐amplitude acoustic signals that have been poorly studied in comparison with loud, broadcast songs used for mate attraction and repelling rivals. In some birds, these soft signals were found to be emitted in an antagonistic context and were the most reliable predictor of a subsequent physical attack. The function of this signal is poorly understood, and several hypotheses have been proposed to explain the mechanisms and possible functions of such low‐amplitude signals. The subject of this study is the ortolan bunting, a small passerine species that produces soft songs during territorial defence. In this study, we aim to study whether the soft songs of the ortolan bunting are a signal of increased aggressiveness by testing if they meet the context, prediction and response criteria of aggressive signals. We simulated stranger male intrusion into a focal male territory with three different playback experiments. We found no significant differences in the male responses to the taxidermic model regardless of whether they were or were not producing soft songs in response. The males responded more strongly to loud songs than to soft songs during the simulated intrusions, and the males did not treat soft songs as a predictor of conflict escalation. Although soft songs clearly appeared during territorial encounters and were not present during spontaneous singing before the intrusions, our results did not support the hypothesis that soft songs indicate aggressive character. We suggest that soft songs in the ortolan bunting are intentionally used by birds to modify their intentions or target‐specific individuals within a close range. 相似文献