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This study reports on the use of a microsystem for evaluation of photodynamic therapy (PDT) procedures on the "mixed" (carcinoma-normal) cultures. Balb/3T3 (normal mouse embryo) and A549 (human lung carcinoma) cells were tested in separated and "mixed" cultures. Interactions and migration of cells cultured together were observed. The PDT procedures were examined in the hybrid (PDMS/glass) microsystem which contains cell culture microchambers integrated with network of microchannels. We investigated that the number of dead cells after PDT procedures is dependent on the kind of cell culture. Moreover, the influence of the carcinoma cells on the viability of normal cells in the "mixed" culture was observed. 相似文献
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Zbigniew Semadeni 《Educational Studies in Mathematics》1984,15(4):379-395
The celebrated principle of the permanence of the rules of calculation is contrasted here with another principle, called concretization permanence principle (c.p.p.). Both apply to situations where some arithmetical operation known to children for numbers of a certain kind is to be extended so as to include further numbers (these numbers are already known to the children). In such a case, c.p.p. advises that a suitable concretization schema and a suitable paradigmatic example be chosen and then extended so as to include numbers of the broader domain; students should explore what the given concept becomes in the new situation and in this way find values of the extended operation for a sequence of examples with fixed concretization (or fixed concretization schema) and varying numbers. 相似文献
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Dorota Kostrzewa-Nowak Robert Nowak Zbigniew Jastrz?bski Aleksandra Zar?bska Marta Bichowska Izabela Drobnik-Kozakiewicz ?ukasz Radzimiński Agata Leońska-Duniec Krzysztof Ficek Pawe? Ci?szczyk 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2015,25(1):103-113
Background
Numerous data suggest that aerobic-type exercise improves lipoprotein-lipid profiles, cardiorespiratory fitness and body composition in young women. The aim of this study was to evaluate the biological response to high-low impact aerobic fitness among young women.Materials and methods
Thirty-four young women aged 22 (19-24) years were divided into three groups: underweight (N = 10), normal weight (N = 12) and overweight (N = 12). Aerobic capacity, anthropometry and body composition together with complete blood count and lipid profile were determined before and after completion of a 12-week-long training period.Results
The training programme caused a significant decrease in weight (by 4.3 kg, P = 0.003), body mass index (by 1.3 kg/m2, P = 0.003), free fat mass (by 2.1 kg, P = 0.002), total body water (by 0.4 kg, P = 0.036), percentage of fat (by 3 percent points, P = 0.002), all analyzed skinfolds thicknesses, as well as the lipid profile in overweight group, and no changes in normal weight group. Significant changes in weight (by 4.2 kg, P = 0.005), body mass index (by 0.9 kg/m2, P = 0.005), crus skinfold thickness (by 3.3 mm, P = 0.028), and in maximum oxygen uptake (by 2.49 mL/kg/min; P = 0.047) were observed among underweight women. No change in total blood count was observed in all groups.Conclusion
Twelve-week-long fitness training programme of two alternating styles (low and high impact) has a beneficial effect on overweight young women.Key words: body composition, physical fitness, overweight, women 相似文献5.
Elzbieta Jastrzebska Ilona Grabowska-Jadach Michal Chudy Artur Dybko Zbigniew Brzozka 《Biomicrofluidics》2012,6(4)
Cell migration is an important physiological process, which is involved in cancer metastasis. Therefore, the investigation of cell migration may lead to the development of novel therapeutic approaches. In this study, we have successfully developed a microsystem for culture of two cell types (non-malignant and carcinoma) and for analysis of cell migration dependence on distance between them. Finally, we studied quantitatively the influence of photodynamic therapy (PDT) procedures on the viability of pairs of non-malignant (MRC5 or Balb/3T3) and carcinoma (A549) cells coculture. The proposed geometry of the microsystem allowed for separate introduction of two cell lines and analysis of cells migration dependence on distance between the cells. We found that a length of connecting microchannel has an influence on cell migration and viability of non-malignant cells after PDT procedure. Summarizing, the developed microsystem can constitute a new tool for carrying out experiments, which offers a few functions: cell migration analysis, carcinoma and non-malignant cells coculture, and evaluation of PDT procedure in the various steps of cell migration. 相似文献
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Radoslaw Kwapiszewski Justyna Szczudlowska Karina Kwapiszewska Michal Chudy Zbigniew Brzozka 《Indian journal of clinical biochemistry : IJCB》2014,29(1):57-62
Early, accurate diagnosis of lysosomal storage disorders is a major challenge, even for trained specialists. Finding innovative, accurate diagnostic methods, and high throughput, cost-effective tools are crucial to medical progress and will contribute to improved quality of life. The goal of this work was to improve currently used protocols to determine activity of acid β-galactosidase, and discuss the possibility analysing lysosomal enzymes with microfluidic systems. A principle of the determination of β-galactosidase activity was fluorometric measurement of a deprotonated form of 4-methylumbelliferone released in the enzymatic reaction. Measurements were performed using Jurkat T cells as a source of the enzyme. We observed the temperature-dependent substrate inhibition effect and determined the substrate (4-MU-β-d-galactopyranoside) concentration which should be used to determine acid β-galactosidase activity at 37 °C (0.8 mM) and at room temperature (0.6 mM). We proved that the sample incubation time may be significantly reduced to only a few minutes. We also showed that the amount of alkaline buffer used to stop the enzymatic reaction may be minimized and even, in some cases, eliminated. The presented results show how the sensitivity of the available methods to diagnose patients suffer from gangliosidosis GM1 or Morquio B disease can be improved. The proposed method may be easily implemented with microfluidic systems, which currently are promising tools for point-of-care applications. 相似文献
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Zbigniew Kmietowicz 《Teaching Statistics》1994,16(3):70-74
This article examines the sampling error of the lead of one political party over another as observed in a random sample of voters. The sample size needed to achieve a certain precision is also investigated. 相似文献
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KULESZA Kamil KOTULSKI Zbigniew 《浙江大学学报(A卷英文版)》2007,8(4):511-521
In the paper we propose a general, abstract framework for Automatic Secret Generation and Sharing (ASGS) that should be independent of underlying Secret Sharing Scheme (SSS). ASGS allows to prevent the Dealer from knowing the secret. The Basic Property Conjecture (BPC) forms the base of the framework. Due to the level of abstraction, results are portable into the realm of quantum computing. Two situations are discussed. First concerns simultaneous generation and sharing of the random, prior nonexistent secret. Such a secret remains unknown until it is reconstructed. Next, we propose the framework for automatic sharing of a known secret. In this case the Dealer does not know the secret and the secret Owner does not know the shares. We present opportunities for joining ASGS with other extended capabilities, with special emphasis on PVSS and pre-positioned secret sharing. Finally, we illustrate framework with practical implementation. 相似文献
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Tertiary Education and Management - Student attrition is a significant problem and a huge challenge from an institutional point of view. Although completion rates in Poland are lower than in most... 相似文献
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