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61.
Wicherek L Mak P Klimek M Banaś T 《European journal of obstetrics, gynecology, and reproductive biology》2007,131(1):97-100
OBJECTIVE: Well-known natural unspecific antimicrobial factors acting in the vagina are additionally reinforced during menstrual bleeding by hemocidins--a recently discovered novel class of microbicidal peptides generated proteolytically from hemoglobin. The aim of the presented research was to investigate the relation between the average length of menstrual bleeding and the frequency of urogenital infections. We expected that the shorter menstrual bleeding might increase the risk of urogenital infections because is synonymous with the shorter period of exposition on bactericidal action of hemocidins. STUDY DESIGN: The study contains statistical analysis of an average declared length of menstrual bleeding in the group of 267 young, sexually active women with the symptoms of urogenital infections. The control group consisted of 300 young healthy women. RESULTS: The length of menstrual bleeding in the group of patients with urogenital infections (average 4.35 days) was statistically significantly shorter than in the control group (average 4.95 days). The average length of the menstrual cycle was equal and counted ca. 28 days in both groups. CONCLUSION: The length of menstrual bleeding seems to be a significant factor in the vaginal ecology maintenance. 相似文献
62.
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
63.
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
64.
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.
65.
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
66.
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
67.
Krzysztof Banaś 《Oceanological and hydrobiological studies.》2013,42(1):28-39
The physico-chemical water characteristics and basin morphology of 10 well-preserved Pomeranian peatland lakes were examined. These are acidic (pH 3.95–5.99), softwater (1.5 ±0.9 mg Ca dm?3), and oligotrophic water bodies. Their hydrochemical conditions differentiate them into two groups: poor (3.04 ±2.77 mg C dm?3) and rich (10.36 ±7.27 mg C dm?3) in organic carbon compounds. They differ in water colour (p = 0.02), humic acid concentration (p<0.001), redox potential (p = 0.007), and irradiance (PAR; p = 0.03). The hydrochemistry of the lakes is determined by their basin morphology, which affects the water colour and the concentrations of humic acids and organic carbon compounds. 相似文献
68.
Peter Gennemark Rasmus Jansson-Löfmark Gina Hyberg Maria Wigstrand Dorota Kakol-Palm Pernilla Håkansson Daniel Hovdal Peter Brodin Maria Fritsch-Fredin Madeleine Antonsson Karolina Ploj Johan Gabrielsson 《Journal of pharmacokinetics and pharmacodynamics》2013,40(6):651-667
Body composition and body mass are pivotal clinical endpoints in studies of welfare diseases. We present a combined effort of established and new mathematical models based on rigorous monitoring of energy intake (EI) and body mass in mice. Specifically, we parameterize a mechanistic turnover model based on the law of energy conservation coupled to a drug mechanism model. Key model variables are fat-free mass (FFM) and fat mass (FM), governed by EI and energy expenditure (EE). An empirical Forbes curve relating FFM to FM was derived experimentally for female C57BL/6 mice. The Forbes curve differs from a previously reported curve for male C57BL/6 mice, and we thoroughly analyse how the choice of Forbes curve impacts model predictions. The drug mechanism function acts on EI or EE, or both. Drug mechanism parameters (two to three parameters) and system parameters (up to six free parameters) could be estimated with good precision (coefficients of variation typically <20 % and not greater than 40 % in our analyses). Model simulations were done to predict the EE and FM change at different drug provocations in mice. In addition, we simulated body mass and FM changes at different drug provocations using a similar model for man. Surprisingly, model simulations indicate that an increase in EI (e.g. 10 %) was more efficient than an equal lowering of EI. Also, the relative change in body mass and FM is greater in man than in mouse at the same relative change in either EI or EE. We acknowledge that this assumes the same drug mechanism impact across the two species. A set of recommendations regarding the Forbes curve, vehicle control groups, dual action on EI and loss, and translational aspects are discussed. This quantitative approach significantly improves data interpretation, disease system understanding, safety assessment and translation across species. 相似文献
69.
70.
Rafał Lasota Karolina Pierścieniak Justyna Miąc Maciej Wołowicz 《Oceanological and hydrobiological studies.》2014,43(3):303-311
Seasonal variations of environmental factors, such as temperature and salinity, require metabolic acclimatization in sedentary benthic fauna distributed over a wide geographical range. The soft-shell clam Mya arenaria inhabits the coastal waters of the North Atlantic including North America and Europe. In Europe, M. arenaria populations are distributed from Iceland to the Mediterranean Sea, including the North Sea, the Baltic Sea and the Black Sea. Seasonal changes in physiological parameters (gonad index, condition index, biochemical composition and respiration rate) of M. arenaria from the Baltic Sea (the Gulf of Gdańsk, Poland), and the North Sea (Versee Meer, the Netherlands) were studied. The sex ratio of both populations did not differ from 1:1 and the seasonal gonad index was higher in the Baltic population. The average condition index changed seasonally at both studied sites, and was also higher in the Baltic population (except the autumn) compared to the North Sea. In both studied populations, the content of proteins, lipids and carbohydrates in the soft tissue followed the seasonal variations, and it was higher in the Baltic population. The respiration rate was lower in the Baltic population, and seasonal changes in the respiration rate seem to be correlated with changes in the water temperature. Based on the results obtained in the present study, we suggest that Mya arenaria is characterized by a large phenotypic plasticity and differences in the observed physiological traits are due to acclimatization to ambient environmental conditions. 相似文献