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DNA adducts, one of genetic damages markers, precede and finally can lead to oncogenic mutations. They appear in genome as a result of DNA bases damages caused by various and numerous environmental factors eg. ultraviolet light, ionic radiation, toxins and also endogenic substances, for example estrogens. It is believed that the creation of DNA adducts is a necessary but insufficient process for the neoplastic transformation of the cell. The following review presents concise knowledge about the DNA adducts creation and their sequels served in healthy and cancerous tissues of the female genital organs, on the base of the available data. 相似文献
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Dorota Dziurka Adam Derkowski Marek Wieruszewski Marcin Kuliski Radosaw Mirski 《Materials》2022,15(11)
Glulam beams are increasingly used in the construction industry because of their high strength and the possibility of using round timber with smaller cross-sections. The load-bearing capacity of beams is strongly related to the quality of the outer layers and, in the case of wood, especially the tension zones. For these reasons, this study decided to replace the outer lamella with tensile plywood. The produced beams were subjected to static bending strength and modulus of elasticity evaluation. It was shown that the best static bending strength values were obtained for beams containing plywood in the tension layer. However, the change in structure in the tension zone of beams made of glued laminated timber results not only in an increase in the load capacity of elements produced in this way but also in a decrease in the range/range of the obtained results of bending strength. This way of modifying the construction of glued laminated beams allows a more rational use of available pine timber. 相似文献
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The paper analyzes the suitability of four types of biomass pellets as a fuel for heating purposes. Three types of waste biomass (sunflower husks, rapeseed cake, and corn straw) and one type of biomass grown for energy purposes (willow) were selected. After appropriate preparation, the selected starting materials were subjected to the pelletization process. Selected physical and chemical properties of the studied biomass pellets were determined. All four types of the analyzed pellets met the EN-ISO-17225-2:2014 standard in terms of bulk density, dimensions, as well as nitrogen and moisture content. The highest calorific value was pellets made of sunflower husk (17.27 MJ/m3) and willow (16.81 MJ/m3), while the calorific value of pellets made of corn straw and rapeseed cake did not exceed 16.5 MJ/m3 and did not meet the standard. In addition, the ash content for these two types of pellets was well above the standard. A 10 kW domestic biomass boiler was employed for burning the tested pellets. The consumption of analyzed fuels during boiler operation was determined. The concentration of CO, CO2, and NOx in exhaust gases was also examined. The obtained experimental results were compared with the numerical calculations with the use of ANSYS Chemkin-Pro using two mechanisms. The highest concentrations of CO2 and CO were observed during the combustion of sunflower and willow husk pellets, which probably resulted from the highest carbon content and, thus, the highest calorific value when compared to cake and straw pellets. For all analyzed pellets, the value of NO and NO2 concentration was similar and did not exceed 368 ppm and 18 ppm, respectively. The results closest to the experiment were obtained for calculations using the mechanism developed by Glarborg et al. The research carried out in the article shows that out of the four analyzed types of pellets, only sunflower and willow husk pellets can be burned in a domestic boiler adapted to burning wood pellets, which is a cheap alternative to wood pellets. 相似文献
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Ilona Jaszczuk Dorota Koczkodaj Adrianna Kondracka Anna Kwaniewska Izabela Winkler Agata Filip 《Annals of medicine》2022,54(1):1350
MicroRNAs (miRNAs) are a class of small non-coding, single-stranded RNAs (ribonucleic acids) that play important roles in many vital processes through their impact on gene expression. One such miRNA, miR210, represents a hypoxia-induced cellular miRNA group that hold a variety of functions. This review article highlights the importance of miR-210 in the development of pre-eclampsia.
KEY MESSAGE
- miR-210 is a promising biomarker for monitoring pregnancy with pre-eclampsia. Overexpression of miR-210 had a negative impact on the process of cell migration and trophoblast invasion.
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Numerous studies have shown that the geometry of micro-joints significantly affects the strength of the so joined timber element. The bending strength increases by creating a larger bonding area by increasing the length of the wedge joint. Although this type of joint has been successfully used for many years, it can still be troublesome to make. For these reasons, the present study investigated an easy-to-fabricate wedge joint, which we folded during the beams’ formation and glued with the same adhesive as the individual lamellas. Although the research has not fully answered all the questions relevant to both scientific and technological curiosity, it indicates the great potential of this solution. Following the principle adopted in the ongoing wood optimisation work, we concluded that the beams of the target cross-section should be produced, and it should only be possible to cut them to a certain length. In this approach, we only removed defects at critical points for the beam structure and, in this way, up to 30% of the timber processed could be saved or better utilised. 相似文献
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Agnieszka Biaek-Dratwa Dorota Szymaska Mateusz Grajek Karolina Krupa-Kotara Elbieta Szczepaska Oskar Kowalski 《Nutrients》2022,14(9)
Avoidant/Restrictive Food Intake Disorder (ARFID) is a relatively new disease entity in DSM-5 and ICD-11. This disorder continues to pose a diagnostic and therapeutic challenge for many professionals. This disorder can affect people of all ages. The most characteristic pattern is considered to be a lack of interest in eating or avoidance of food intake, which may result in nutritional deficiencies, weight loss or lack of expected weight gain, dependence on enteral feeding or dietary supplements, and impaired psychosocial functioning. This disorder cannot be explained by a current medical condition or co-occurring other psychiatric disorders, but if ARFID co-occurs with another disorder or illness, it necessarily requires extended diagnosis. Its treatment depends on the severity of the nutritional problem and may include hospitalization with multispecialty care (pediatrician, nutritionist, psychologist, psychiatrist, neurologist). The nutritional management strategy may include, inter alia, the use of Food Chaining, and should in the initial stage of therapy be based on products considered “safe” in the patient’s assessment. The role of the dietitian in the management of a patient with ARFID is to monitor weight and height and nutritional status and analyze the foods that should be introduced into the food chain first. 相似文献
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Transferrin (Tf) is a glycoprotein responsible for iron transport in the human body. Physiologically in reaction with Concanavalin A, Tf occurs in four distinct variants Tf1, Tf2, Tf3 (apo-Tf) and Tf4. It was reported recently that Tf is changing, particularly during acute phase response, taking place among others in end-stage renal disease. In this study, we wanted to find the answer to three main questions: firstly, how Tf is changing in patients treated with maintenance haemodialysis (mHD), secondly, whether there are any Tf changes in the course of mHD treatment, and thirdly, what factors can affect Tf microheterogeneity in these patients. Studies were performed on 80 haemodialysed patients and 21 healthy volunteers. The Tf concentration was determined by the rocket immunoelectrophoresis, and its microheterogeneity was assessed by the ConA crossed immunoaffinity electrophoresis. During the annual observation of the distribution of the Tf variants, we have found both changes of the percentage contents of all Tf variants in the whole Tf concentration and a significant decrease in Tf2, Tf3 and Tf4 serum concentrations. Moreover, we found that decrease in the renal function, duration of mHD, and inflammation may contribute to these above-mentioned changes, which are probably the factors that should be taken into account when explaining the mechanisms of persistence of anaemia in haemodialysed patients. 相似文献
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