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61.
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
62.
Prognostic value of selected platelet parameters of patients operated for non-small cell lung cancer
Mariusz ochowski Marek Rbowski Justyna Chaubiska-Fendler Izabela Zawadzka Barbara ochowska Bartosz Cielik-Wolski Jzef Kozak 《Journal of thoracic disease》2022,14(5):1374
BackgroundPlatelets play a vital role in the neoplastic process. Platelet parameters are hence an important source of information concerning ongoing neoplastic disease. The aim of the study is to assess the impact of selected platelet parameters on the survival of patients with non-small cell lung cancer (NSCLC).MethodsThe study included 532 (174 female and 358 male) patients aged 36–84 years (mean age 63.6 years) operated on due to NSCLC, staged IA–IIIA. Before the operation, all patients received a blood morphology test. The following parameters were subjected to statistical analysis: platelet count, mean platelet volume (MPV) parameter, platelet distribution width (PDW) parameter, platelet-to-lymphocyte ratio (PLR) and systemic immune-inflammation (SII) index. These findings were compared with the clinical data of the patients, and the probability of overall survival was analyzed.ResultsThe univariate analysis revealed a correspondence between PDW, MPV, PLR and SII index and patient survival. The multivariate analysis including patient clinical data found the following factors to have negative prognostic value for patients operated on due to NSCLC: male sex, advancement stage of neoplastic disease and Charlson Comorbidity Index (CCI) above 4, and PLR >144.ConclusionsPDW value, PLR and SII index are independent prognostic factors. In the multi-factor model, male sex, the advancement stage of the neoplastic disease, CCI above 4 and PLR lower than 144 had the greatest prognostic value. 相似文献
63.
Peter ?alamún Marek Ren?o Eva Kucanová Tímea Brázová Ingrid Papajová Dana Miklisová Vladimíra Hanzelová 《Ecotoxicology (London, England)》2012,21(8):2319-2330
The effect of distance from a heavy metal pollution source on the soil nematode community was investigated on four sampling sites along an 4?km transect originating at the Kovohuty a.s. Krompachy (pollution source). The soil nematode communities were exposed to heavy metal influence directly and through soil properties changes. We quantified the relative effects of total and mobile fraction of metals (As, Cd, Cr, Cu, Pb, and Zn) on soil ecosystem using the nematode community structure (trophic and c-p groups,) and ecological indices (Richness of genera, H′, MI2-5, etc.). Pollution effects on the community structure of soil free living nematodes was found to be the highest near the pollution source, with relatively low population density and domination of insensitive taxa. A decrease in heavy metals contents along the transect was linked with an increase in complexity of nematode community. The majority of used indices (MI2-5, SI, H′) negatively correlated (P?<?0.05 or P?<?0.01) with heavy metals content and were sensitive to soil ecosystem disturbance. Contamination by heavy metals has negatively affected the soil environment, which resulted in nematode community structure and ecological indices changes. Results showed that the free-living nematodes are useful tools for bioindication of contamination and could be used as an alternative to the common approaches based on chemical methods. 相似文献
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Agnieszka Mazur Anna Szylling Teresa Bielecka Marek Kulus 《The Journal of asthma》2013,50(10):1147-1155
Objective: The prevalence of allergic diseases has reached epidemic proportions in the Western world. Although farm-living has been associated with a lower prevalence of asthma and atopy, a marked increase in atopy among rural populations after accession to the European Union has been recently reported in Poland. Here, we aimed to investigate the effect of living environment on the prevalence of atopy and allergic diseases in Polish children. Methods: 400 schoolchildren aged 10–14 years from the capital city (223) and from traditional rural part of the country (177) were recruited from June to November 2011. Data on allergic diseases and symptoms were collected by means of questionnaire and physical examination. Atopy was assessed based on skin prick tests (SPTs) reactivity to inhalant allergens in 350 children. Results: A high discrepancy between the prevalence of allergic symptoms (46.7%) and doctor-diagnosed allergic diseases (25%) was demonstrated (p < 0.0001). Urban children had a higher overall prevalence of allergic diseases and atopy than children living in rural areas, 29.3% versus 17.1% (p = 0.007) and 33.5% versus 20% (p = 0.0045), respectively. However, no significant differences in the rates of particular allergic diseases were noted (p > 0.05). There was higher SPT positivity to trees, grass, corn, weeds, animal dander, and molds in urban children (p < 0.05). Conclusions: Our data support the protective effect of farm-living on the prevalence of atopy and overall allergic diseases, albeit not on particular allergic diseases, in children in Poland. The underlying mechanisms are not identified, but current socioeconomic changes may be responsible. 相似文献
68.
Altered NKG2D function in NK cells induced by chronic exposure to NKG2D ligand-expressing tumor cells 总被引:11,自引:0,他引:11 下载免费PDF全文
NKG2D is an activation receptor that allows natural killer (NK) cells to detect diseased host cells. The engagement of NKG2D with corresponding ligand results in surface modulation of the receptor and reduced function upon subsequent receptor engagement. However, it is not clear whether in addition to modulation the NKG2D receptor complex and/or its signaling capacity is preserved. We show here that the prolonged encounter with tumor cell-bound, but not soluble, ligand can completely uncouple the NKG2D receptor from the intracellular mobilization of calcium and the exertion of cell-mediated cytolysis. However, cytolytic effector function is intact since NKG2D ligand-exposed NK cells can be activated via the Ly49D receptor. While NKG2D-dependent cytotoxicity is impaired, prolonged ligand exposure results in constitutive interferon gamma (IFNgamma) production, suggesting sustained signaling. The functional changes are associated with a reduced presence of the relevant signal transducing adaptors DNAX-activating protein of 10 kDa (DAP-10) and killer cell activating receptor-associated protein/DNAX-activating protein of 12 kDa (KARAP/DAP-12). That is likely the consequence of constitutive NKG2D engagement and signaling, since NKG2D function and adaptor expression is restored to normal when the stimulating tumor cells are removed. Thus, the chronic exposure to tumor cells expressing NKG2D ligand alters NKG2D signaling and may facilitate the evasion of tumor cells from NK cell reactions. 相似文献
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BackgroundCT angiography is used as a non-invasive method in the evaluation of patients with Fontan circulation. For good visualization of patients having undergone the Fontan operation the optimal scan timing and adequate intravenous route is important.PurposeThe aim of this study was to confirm that computer tomography is very a good tool for assessment of patients after Fontan procedure with implanted stents in pulmonary arteries or in fenestration.Material and methodsSix patients with Fontan circulation and implanted stent in left pulmonary artery or in fenestration underwent CT angiography. The CT angiography was successfully performed to all patients. For homogenous enhancement of Fontan pulmonary arteries and Fontan tract we decided to use 1-minute delay scan with right antecubital application of contrast agent. The optimal enhancement was evaluated at the right pulmonary artery (RPA), left pulmonary artery (LPA), and Fontan tract. Optimal enhancement was defined when evaluation of stent was possible.ResultsOptimal enhancement when the stent was possible to evaluate intraluminally was achieved in seven CT examinations. The Bland–Altman test demonstrated good agreement between readers.ConclusionsThis study demonstrates that CT angiography is a fast, accurate and reproducible method in the evaluation of patients with Fontan circulation, and implanted stent in pulmonary arteries or in fenestration. 相似文献