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21.
Since the end of 2019, the whole world has been struggling with the life-threatening pandemic amongst all age groups and geographic areas caused by Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV-2). The Coronavirus Disease 2019 (COVID-19) pandemic, which has led to more than 468 million cases and over 6 million deaths reported worldwide (as of 20 March 2022), is one of the greatest threats to human health in history. Meanwhile, the lack of specific and irresistible treatment modalities provoked concentrated efforts in scientists around the world. Various mechanisms of cell entry and cellular dysfunction were initially proclaimed. Especially, mitochondria and cell membrane are crucial for the course of infection. The SARS-CoV-2 invasion depends on angiotensin converting enzyme 2 (ACE2), transmembrane serine protease 2 (TMPRSS2), and cluster of differentiation 147 (CD147), expressed on host cells. Moreover, in this narrative review, we aim to discuss other cell organelles targeted by SARS-CoV-2. Lastly, we briefly summarize the studies on various drugs.  相似文献   
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An analytical model was developed to determine the temperature of friction coupling, in which one element was made of a functionally graded material (FGM) and the other was homogeneous. First, for such a system, the boundary–value problem of heat conduction was formulated with consideration of the heat generation due to friction. Then, using the Laplace integral transform, an exact solution to this problem was obtained for uniform sliding, and braking with constant deceleration. A numerical analysis was performed for the selected friction pair consisting of the FGM (zircon dioxide + titanium alloy) and cast iron. It was established that the use of elements made of a FGM consisting of ZrO2 and Ti-6Al-4V can significantly reduce the maximum temperature achieved in the friction system.  相似文献   
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IntroductionRecently introduced microUSB ultrasound probe, which can be connected to personal mobile device constitutes a new class of diagnostic pocket size imaging devices (PSID).The aim of this study was to assess the feasibility and clinical utility of real-time tele-echocardiography with the use such device.Material and methodsThe study group comprised 30 patients (18 men and 12 women; mean age: 54 ±14 years; mean body mass index: 27 ±6 kg/m2), admitted to various hospital departments (infectious diseases, internal medicine and cardiology). All patients underwent focused echocardiographic examination performed by an inexperienced operator using PSID and collaborating remotely in real-time with cardiologist by means of tele-consultation. Before commencing the examination, the operators underwent 1 h training in use of the PSID.ResultsIn most of patients PSID imaging provided sufficient diagnostic image quality. The dimensions of left ventricle, left atrium and the aorta obtained during the this examination showed good correlation with standard echocardiography (r = 0.89, r = 0.82, r = 0.92 respectively), but the correlation for TAPSE measurements was less pronounced (r = 0.52). The agreement in detection of pathologies (wall motion abnormalities, morphological and functional valvular abnormalities) between the tele-echocardiography and standard echocardiographic examination was good to very good (κ ranged from 0.648 to 0.823).ConclusionsPocket size imaging devices allows an inexperienced operator to perform a focused echocardiographic examination under a remote supervision of an experienced cardiologist. The introduction of new technology in the form of PSID with tele-echocardiography feature can revolutionize access to this imaging technique.  相似文献   
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Background: Osteoprotegerin (OPG) is a molecule which belongs to the tumor necrosis factor receptor superfamily. OPG concentration is elevated in patients with left ventricle hypertrophy, heart failure and acute myocardial infarction. OPG concentrations rise in chronic kidney disease (CKD). The aim of this study was to investigate the association between OPG concentrations and cardiovascular complications, such as left ventricle hypertrophy, systolic and diastolic dysfunction of left ventricle and dysfunction of right ventricle in chronic kidney disease patients not treated with dialysis. The relation between OPG and the amount of pericardial fluid was also examined. Methods: One hundred and one men with CKD stage 3–5 not treated with dialysis were included in the study. Overhydration, body fat mass and lean body mass were measured using bioimpedance spectroscopy (BIS). Echocardiography was performed to evaluate the amount of pericardial fluid and to measure the thickness of the interventricular septum (IVS), systolic and diastolic function of left ventricle, as well as systolic function of right ventricle. Results: We observed a significant positive association between OPG and the thickness of the interventricular septum, the size of the left atrium (LA) and the presence of pericardial fluid. A negative relationship was observed between OPG and ejection fraction (EF). Conclusions: Our results suggest that OPG can be an independent marker of left ventricular hypertrophy, systolic and diastolic dysfunction of left ventricle and the presence of pericardial fluid in chronic kidney disease patients.  相似文献   
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The impact of selenium on the course of Hashimoto’s thyroiditis (HT) was mainly assessed by monitoring the titer of antithyroid autoantibodies in most of the studies conducted hitherto. On the other hand, the imbalance in activity of T cells such as Th1, Th2, Th17, and Treg may be relevant in the pathogenesis of this disease. Hence, the assessment of changes in the secretion of cytokines by these cells during selenium supplementation in patients with HT seems to be an important issue and was the main goal of this study. A further aim was to search for correlations among these cytokines, as well as markers of thyroid function, selenium/iodine status in the body, and other biochemical parameters. The group of 29 women with newly diagnosed Hashimoto’s thyroiditis was supplemented with selenium in a dose of 100 µg/day for 6 months. Immunological parameters: interferon γ, tumor necrosis factor α, chemokine CXCL10, interleukin 4, interleukin 1β, interleukin 17, transforming growth factor β, and C-reactive protein, as well as selenium status parameters were determined in serum twice, i.e., before and after supplementation. Selenium supplementation was associated with a change in the production of two cytokines: interferon γ and interleukin 1β, for which a decrease and an increase in concentration were observed, respectively. The partial least squares (PLS) model revealed the presence of many relevant correlations among analyzed parameters. The stage of HT development, degree of thyroid dysfunction, and selenium supplementation of diet are interdependent factors which shape the profile of some cytokines secreted by cells participating in the autoimmunity process.  相似文献   
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The impact of the amount of durum wheat bran additive used on the selected structural, mechanical, and spectroscopic properties of thermoplastic starch moldings was examined in this study. Bran was added to corn starch from 10 to 60% by weight in the blends. Four temperature settings were used for the high-pressure injection: 120, 140, 160, and 180 °C. The highest value of elongation at break (8.53%) was observed for moldings containing 60% bran. Moreover, for these moldings, the tensile strength and flexural strength were lower (appropriately 3.43 MPa and 27.14 MPa). The highest deformation at break (1.56%) were obtained for samples with 60% bran and injection molded at 180 °C. We saw that higher bran content (50 and 60%) and a higher injection molding temperature (160 °C and 180 °C) significantly changed the color of the samples. The most significant changes in the FTIR spectra were observed at 3292 and 1644 cm−1 and in the region of 1460–1240 cm−1. Moreover, notable changes were observed in the intensity ratio of bands at 1015 and 955 cm−1. The changes observed correspond well with the amount of additive used and with the injection temperature applied; thus it may be considered as a marker of interactions affecting plasticization of the material obtained.  相似文献   
28.
The global use of petroleum hydrocarbons as raw materials and an energy source in industry results in serious environmental, health, and ecological problems. Consequently, there is growing interest in the development of technologies for the rehabilitation of contaminated areas. This study was undertaken in order to determine the effect of different phytostabilising materials (compost, bentonite, and CaO) on the trace element content in soil contaminated with unleaded petroleum 95 (0, 2.5, 5, and 10 cm3 kg−1 of soil). The doses of petroleum applied to the soil were based on the previously conducted preliminary experiment. The highest petroleum dose (10 cm3 kg−1 of soil) significantly reduced the chromium, zinc, and cobalt contents in the soil. Petroleum increased the cadmium, lead, nickel, and copper contents in the soil. The materials used for phytostabilisation (compost, bentonite, calcium oxide) had a significant effect on the trace element content in the soil. The application of mineral materials (bentonite and calcium oxide) was more effective than the application of compost, compared to the control series (without soil amendments) as they reduced the contents of cadmium, chromium, nickel, and cobalt in the soil to the greatest extent. The reduction effect of bentonite and calcium oxide on the content of these trace elements in the soil was stronger than compost.  相似文献   
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OBJECTIVES: to confirm that fetal echocardiography is indeed possible in late first trimester and that it improves the standard of the so-called "genetic" ultrasound scan. MATERIAL AND METHODS: Early echocardiography was performed in 75 fetuses from high and low risk pregnancies. All fetuses underwent echocardiography examination in 18-22 weeks of gestation and established follow up. RESULTS: The most suitable method of visualization seems to be transabdominal examination, between 13.0-13.6 weeks of gestation, an transvaginal one, between 12.0-12.6 weeks of gestation, with 90% effectiveness. In researched group of 75 fetuses (with established follow up) there were four heart defects (5.3%). Three of them were diagnosed before 14th week of gestation. One case (tetralogy of Fallot) was overlooked. There were two false positive diagnosis verified at 20th week of gestation. CONCLUSIONS: Early echocardiography, especially between 12.0-13.6 weeks of gestation, is a possible and valuable method of diagnosis. Reference evaluation should be performed between 18 and 22 weeks of gestation. In cases with suspected anomalies karyotyping is recommended. Congenital heart disease diagnosed at late first trimester should be treated as the next potential marker of genetic disorder.  相似文献   
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