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1.
Background and aimsLimited number of studies investigated lipid profile in chronic obstructive pulmonary disease (COPD) with inconsistent results. This study aimed to investigate lipid parameters in sera of patients with stable COPD and their associations with disease severity, smoking, comorbidities and therapy.Methods and resultsThe study included 137 COPD patients and 95 controls. Triglycerides (TG), total cholesterol (TC), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) were assessed. Non-HDL-C (NHC), atherogenic coefficient (AC), TG/HDL-C, atherogenic index of plasma (AIP), Castelli's risk index I and II (CRI-I, CRI-II), and monocyte to HDL ratio (MHR) were calculated.HDL-C and MHR were increased, while other lipid parameters and indices were decreased in COPD patients compared to healthy individuals. Smoking did not influence lipid parameters. However, lipid profile was altered only in more severe disease stages. AC, CRI-I and CRI-II showed positive association with lung function parameters in COPD patients, and negative with COPD multicomponent indices (ADO, BODCAT, BODEx, CODEx and DOSE). Combined model that included CRI-II, C-reactive protein, fibrinogen and white blood cells showed great diagnostic performances, and correctly classified 72% of study participants with an AUC of 0.800 (0.742–0.849), P < 0.001. Bronchodilator monotherapy and statins have opposite impact on TC, LDL-C and NHC, while TG, TG/HDL-C and AIP were increased in COPD patients with cardiovascular diseases.ConclusionLipid disbalance is present in COPD, and it seems to occur later as the disease progresses. Further studies are needed to illuminate the underlying mechanism of dyslipidaemia.  相似文献   
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Total hip replacement revision surgery is accompanied by significant blood loss. Using rotational thrombelastometry (ROTEM) perioperatively to diagnose coagulopathy may help to provide rapid aimed therapy and thus decrease blood loss and the consumption of transfusion products. The aim of this case-control study was to find out whether point of care using of ROTEM may reduce blood loss and the consumption of blood transfusion products in hip replacement revision surgery.Data were prospectively collected from patients who underwent hip replacement revision surgery in the period 2017 to 2018 when the management of bleeding and coagulopathy was based on the results of ROTEM. Data were compared with a group of historical controls for the period 2015 to 2016 when bleeding and coagulopathy management was not based on ROTEM results. The consumption of blood transfusion products and perioperative blood loss were compared between the groups.The total number of analyzed patients was 90. Forty five patients were analyzed in the ROTEM group and the same number of patients were analyzed in the non-ROTEM group. Significantly decreased perioperative consumption of fresh frozen plasma and packed red blood cells was found in the ROTEM, as well as decreased perioperative blood loss comparing to non-ROTEM group. All data were statistically different with P < .05.Perioperative management of bleeding and coagulopathy based on the results of ROTEM during hip replacement revision surgery seems to help to decrease perioperative blood loss and the consumption of blood transfusion products, especially fresh frozen plasma.  相似文献   
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In this article, construction of amperometric sensor(s) based on screen-printed carbon electrodes covered by thin layers of two types of carbon nanomaterials serving as amplifiers, and containing [Cu(bipy)2Cl]Cl∙5H2O complex is reported. Their performance and biomimetic activity towards two selected neurotransmitters (dopamine and serotonin) was studied mainly using flow injection analysis (FIA). The important parameters of FIA such as working potential, flow rate, and pH were optimized. The mechanism of the catalytic activity is explained and experimentally confirmed. It reveals that presence of hydrogen peroxide plays a crucial role which leads to answer the title question: can presented complex really be considered as a tyrosinase biomimetic catalyst or only as a redox mediator?  相似文献   
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Abstract

Pyridostigmine bromide acts as a reversible cholinesterase inhibitor that is used at relatively high doses in treatment of Myasthenia gravis and in low dose regimens as prophylaxis against nerve agents poisoning during the Gulf War. The manifestation of late nonspecific symptoms commonly called Gulf War illness has led to the discussion about the role of pyridostigmine bromide in the pathogenesis of this illness. In our study, we described plasma absorption profile of pyridostigmine bromide after p.o. administration in rats; subsequently, changes in blood biochemical and oxidative stress markers were measured. Pyridostigmine bromide was applied p.o. at the dose of 5.82?mg/kg b.w. according to the previously published recommendations. The absorption of pyridostigmine was relatively fast; the Cmax in plasma was 110.20?±?15.12?ng/ml at Tmax of 197.12?±?17.14?min. The bioavailability expressed as AUCtotal was 44,348?±?7608?min ng/ml. The prolongation of pyridostigmine in circulation is in agreement with relatively long half-life that was 179.00?±?28.54?min. Several blood biochemical markers were altered, including glucose, creatinine, creatine kinase, alanine aminotransferase, aspartate aminotransferase, interleukin-6, triglycerides, and cholesterol. However, the changes could be considered as mild. Thiobarbituric acid reactive substances and ferric reducing ability of plasma indicate suppression of basal metabolism. The results of blood biochemical and oxidative stress markers imply that long-term use might possibly change the basal metabolism and cause cellular damage with inflammatory changes.  相似文献   
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In this paper, we present the methodology for determining the point model of the ilium bone in cases when volumetric data of the whole bone are not available. An extreme traumatic bone damage, osteoporosis, destruction of bone tissue by malignant bone tumors or the existence of only 2D medical image (X-ray) can be the reason for the lack of complete volumetric data. Points on the bone surface were defined at the curves that run through 26 previously defined parameters, at the edges of anteroposterior (A–P) and lateral projections and at the parts of the surface between some parameters. Those parts of the surface, enclosed by parameters, represent ten parametric regions. The values of coordinates, which represent the input data in the statistical program, were measured in a uniquely defined coordinate system. After establishing the correlations between the values of coordinates, 8869 different linear and nonlinear regression models were obtained. The prediction values for point coordinates were calculated and exported to a CAD program. Results obtained were tested on a randomly chosen male right ilium bone, applying the methodology for creating the prediction model using the method of parametric regions, which allows creating a complete polygonal model, for each region separately or just for some parts of the region. Results obtained in the form of regression equations for the right ilium bone can be applied to the left ilium bone. The results of the research were verified using a comparative deviation and distance analysis between the initial and obtained polygonal models.  相似文献   
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Manganese concentrations were determined in muscle, kidney, liver, spleen, lung and fat tissues and skin of three cetacean species, the bottlenose (Tursiops truncatus), striped (Stenella coeruleoalba) and Risso’s (Grampus griseus) dolphins, stranded along the Croatian Adriatic coast between 1995 and 2013. Mean ranges determined in tissues were (mg/kg, ww): muscle 0.23–0.27, liver 2.87–4.00, kidney 0.66–1.26, spleen 0.37–0.79, lung 0.18–0.57, skin 0.11–0.97, fat 0.06–0.42. The highest Mn mean levels in tissues were measured in species (mg/kg, ww): T. truncates lung 0.41, skin 0.97, fat 0.42; S. coeruleoalba muscle 0.26; G. griseus kidney 1.26, liver 4.00, spleen 0.64. Significant differences of Mn concentrations in the liver (p?=?0.034), spleen (p?=?0.037) and skin (p?=?0.013) were found among the three dolphin species. Significant differences in Mn levels were found between young and adult T. truncates in kidney (p?=?0.042), lung (p?=?0.0040) and skin (p?=?0.0034).  相似文献   
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OBJECTIVE: Three-dimensional analysis of palate size and shape in patients with isolated cleft palate at the stage of permanent dentition. DESIGN: Cross-sectional study using Fourier transform profilometry.Subjects: Twenty-nine randomly selected dental casts of approximately 15-year-old boys with isolated cleft palate and 28 dental casts of normal boys of the same age.Interventions: All patients were operated on by the same method (pushback and pharyngeal flap surgery) at a mean age of 4.5 years. MAIN OUTCOME MEASURES: Data on the palate height in 210 defined locations (pixels). RESULTS: The palate in isolated clefts is narrower throughout its whole extent and lower from the level of the first premolars. The difference, as compared with controls, increases in a posterior direction. At the level of the first molars, palatal height is reduced by one-quarter, the area of the transversal section by more than one-third. The shaping of the palate vault is, on average, symmetrical with a marked interindividual variability. Palatal height does not depend on the width of the dentoalveolar arch, and the height of the primary palate is not reduced. CONCLUSION: The smaller width and reduced height from the level of the first premolars posteriorly confirm the substantially reduced space available for the tongue in patients with isolated cleft palate. Deviations are on the average symmetrical, and the anterior part of the palate is not shallower.  相似文献   
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