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101.
This article presents a method of filtering thermal images by means of approximation using cubic B-spline patch surfaces. Approximation uses chord length parameterization with non-uniform distribution of knots, depending on the change rate of pixel values in rows and columns of the image. Advantages of approximation with such parameterization are compared with popular uniform parameterization. Presented method is very versatile and can be used for example in 3D surface topography of objects tested with stereoscopic microscopes, in resolution change of arbitrary images or modeling processes depending on two parameters. Filtering results are presented using plugin for the Soft4Image program, which was designed to unify different digital signal processing algorithms.  相似文献   
102.
We consider large-scale dynamical systems in which both the initial state and some parameters are unknown. These unknown quantities must be estimated from partial state observations over a time window. A data assimilation framework is applied for this purpose. Specifically, we focus on large-scale linear systems with multiplicative parameter-state coupling as they arise in the discretization of parametric linear time-dependent partial differential equations. Another feature of our work is the presence of a quantity of interest different from the unknown parameters, which is to be estimated based on the available data. In this setting, we employ a simplicial decomposition algorithm for an optimal sensor placement and set forth formulae for the efficient evaluation of all required quantities. As a guiding example, we consider a thermo-mechanical PDE system with the temperature constituting the system state and the induced displacement at a certain reference point as the quantity of interest.  相似文献   
103.
104.
Two groups of hypertensive patients: 137 responsive (on one or two drugs) and 162 resistant on antihypertensive treatment in the similar age were compared. Resistant patients (on three or more drugs) characterize by significantly higher body weight and BMI, longer history of hypertension, more frequent hypertension prevalance in family members and lower education. Level of triglycerides in resistant on antihypertensive treatment patients was significantly higher than in responsive patients. Insulin level in blood in 31 patients with essential hypertension was significantly higher than in 36 healthy persons and 20 patients with renovascular hypertension and resistant on antihypertensive therapy. In 14 patients with essential hypertension resistant to treatment insulin level one hour after oral glucose load was significantly (p < 0.01) higher than in 16 patients with essential hypertension responsive to antihypertensive treatment.  相似文献   
105.
The aim of this study was to assess the effects of myocardium organic damage on time-domain parameters of atrial signal-averaged ECG (ASAECG) in patients with electrically induced paroxysmal atrial fibrillation (PAF). The investigation was done in 120 patients with subjective symptoms of cardiac rhythm disorders suggesting atrial fibrillation and for further analysis were selected 51 patients in whom atrial PAF was induced during transoesophageal pacing (TEP). Patients were divided according to organic damage of myocardium-38 pts (24 male and 14 female, mean age 52.1 +/- 11.6-group I) and without-13 pts (9 male and 4 female, mean age 35.4 +/- 9.9 -group II). In all two dimensional echocardiographic examination, 24-hours Holter monitoring, exercise testing and TEP were made. Recording of ASAECG was done with a commercially available system HIPEC-200 HA Aerotel. The following time-domain parameters of ASAECG were calculated: the root mean square voltage of the terminal 10, 20, 30 ms of the filtered P-wave (RMS 10, 20, 30) and time duration of filtered P-wave (PWD) and also time duration of P-wave from Frank's leads X, Y, Z (XP, YP, ZP). Atrial late potentials (ALP) were defined as the presence of two parameters: RMS 10 < 4 microV and PWD > 123 ms. If we compared time-domain parameters of ASAECG between examined groups it occurred that only the values of PWD attained statistically significant differences, respectively 123.3 +/- 15.4 ms vs 115 +/- 11.2 ms, p < 0.05. In 14 (36.8%) patients from first group and in 2 (15.4%) patients from second ALP were confirmed. We concluded that presence of myocardium organic damage have essentially influenced on time duration of filtered P-wave.  相似文献   
106.
HDL cholesterol (HDL-C) levels are inversely related to coronary heart disease (CHD) risk, and HDL-C distributions vary among countries. Poland is one of the few developed countries in which CHD rates are increasing at the same time that US rates have been falling, but whether these differences are explained by differences in risk factors such as HDL-C has not been determined. To examine this possibility, levels of HDL-C and its subfractions were compared in US and Polish urban and rural men and women aged 45 to 64 years. Age-adjusted HDL-C means were 0.20 mmol/L higher in urban Polish men and 0.37 mmol/L higher in rural Polish men than in their US counterparts (P < .0001); means in urban Polish women were 0.06 mmol/L higher (P < .05) and in rural Polish women 0.09 mmol/L higher (P < .001) than in their US counterparts. Adjustment for age, education, alcohol intake, smoking, BMI, heart rate, and menopause status (in women) had little effect on differences. Means of HDL2 and HDL3 levels showed similar between-country differences, although differences were minimal for HDL2 in urban men and women, and HDL3 means did not differ between rural women. BMI was inversely related to HDL-C and both subfractions in all gender-country-site strata (P < .001), and alcohol was directly related to HDL-C (P < .001) in all strata except Polish women. Cigarette smoking was negatively related to HDL-C and both subfractions in all US samples except HDL2 in urban men, whereas in Polish samples, significant associations were found only in urban women for HDL-C and in rural and urban women for HDL3. Age, heart rate, and education showed inconsistent or no association with HDL-C and its subfractions in either country. This profile of HDL-C and its subfractions in Polish samples contrasts sharply with the opposite trend in CHD mortality rates, which suggests either that other risk factors may account for the trends or that the relationship between HDL-C and CHD may differ between the two countries.  相似文献   
107.
The purpose of the work was an assessment of the usefulness of transcutaneous measurement of O2 pressure in the foot (in recumbent position, recumbent with venostasis, elevated and erect position) for the detection of microcirculation disturbances in patients with diabetes mellitus. The studies included 43 patients with type I and II diabetes without haemodynamically significant stenoses of the axial arteries of the lower limbs, and a control group of 14. It was found that already in the period preceding the development of obliterative lesions in the arteries, microcirculation disturbances in the lower limbs became manifest causing statistically significant decrease of tcPO2 in patients with type I and II diabetes mellitus. The values of tcPO2 in position with limb elevation differentiate best these two groups of patients.  相似文献   
108.
The aim of the study was to establish the frequency of occurrence of bacterial pathogens with beta-lactamase activity, and pattern of resistance among aerobic and anaerobic strains isolated from: respiratory tract, urinary tract, skin and soft tissues (hospitalized patients) and throat swabs (ambulatory patients). The study was conducted in 1994 year in 6 bacteriological laboratories in four Polish towns (Warszawa, Kraków, Katowice, Gdańsk) according to the protocol. Sensitivity of bacteria was tested by the disc method on the Müeller-Hinton agar or chocolate agar according to NCCLS, activity of beta-lactamase was tested with nitrocephin. A total 2038 clinical strains--1869 aerobic and 169 anaerobic was well-defined and tested for susceptibility to ten antibiotics--amoxicilin, augmentin, ofloxacin, gentamycin, cefradin, erythromycin, cefuroxim, kotrimoxazol, cefalexin and cefaclor. Among the isolated aerobes Staphylococcus aureus (25.1%), E. coli (23.2%) and Haemophilus influenzae (14.0%) were most frequent, and in the group of anaerobes the most frequent were Bacteroides spp (40.8%) We have found 45.8% of all tested aerobic strains with beta-lactamase production, the highest proportion in pathogens isolated from respiratory tract--51.4%, 46.6% from urinary tract, and 48.4% from skin and soft tissues. Among the isolated anaerobic--68.8% of Bacteroides and 28.6% others produced beta-lactamase. Forty percentage of all strains were sensitive to amoxicilin, 70-90% of aerobic bacteria were sensitive to augmentin. Augmentin had a high activity against anaerobic bacteria too. Only a small proportion of the tested aerobic bacteria (12.2%) were resistant to ofloxacin, gentamycin showed a sufficient activity against tested strains (24.4% were resistant). The most frequent pathogen--Staphylococcus aureus was resistant to amoxicilin in 83.1% hospitalized patients, and in 73.9% in ambulatory patients.  相似文献   
109.
Palmitic acid (C16:0) is the most abundant saturated fatty acid in animals serving as a substrate in synthesis and β-oxidation of other lipids, and in the modification of proteins called palmitoylation. The influence of dietary palmitic acid on protein S-palmitoylation remains largely unknown. In this study we performed high-throughput proteomic analyses of a membrane-enriched fraction of murine liver to examine the influence of a palm oil-rich diet (HPD) on S-palmitoylation of proteins. HPD feeding for 4 weeks led to an accumulation of C16:0 and C18:1 fatty acids in livers which disappeared after 12-week feeding, in contrast to an accumulation of C16:0 in peritoneal macrophages. Parallel proteomic studies revealed that HPD feeding induced a sequence of changes of the level and/or S-palmitoylation of diverse liver proteins involved in fatty acid, cholesterol and amino acid metabolism, hemostasis, and neutrophil degranulation. The HPD diet did not lead to liver damage, however, it caused progressing obesity, hypercholesterolemia and hyperglycemia. We conclude that the relatively mild negative impact of such diet on liver functioning can be attributed to a lower bioavailability of palm oil-derived C16:0 vs. that of C18:1 and the efficiency of mechanisms preventing liver injury, possibly including dynamic protein S-palmitoylation.  相似文献   
110.
Methanolic extracts of processed fruiting bodies of six edible mushroom species (Basidiomycota) - Armillaria mellea, Boletus badius, Boletus edulis, Cantharellus cibarius, Lactarius deliciosus collected from natural habitats and Pleurotus ostreatus of commercial origin - were analysed for the presence of non-hallucinogenic indole compounds. Thermal processing was designed in such a way that it mimicked conditions used for cooking of mushroom dishes, since only a narrow group of mushrooms can be eaten raw, while indole compounds are thermolabile. All processed extracts were shown to contain l-tryptophan (up to 8.92 mg/100 g dw). The contents of the remaining compounds, 5-methyltryptophan, tryptamine, melatonin, indoleacetonitrile and indole, varied in different species (from 0.71 to 6.55 mg/100 g dw). Extract of processed C. cibarius fruiting bodies contained l-tryptophan, 5-methyltryptophan, tryptamine, melatonin, indoleacetonitrile and indole (1.96-4.94 mg/100 g dw) whereas l-tryptophan (2.78 mg/100 g dw) and tryptamine (2.77 mg/100 g dw) were the only indole compounds identified in the processed fruiting bodies of A. mellea.  相似文献   
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