Previous observation demonstrated that measured nucleolar and nuclear diameters and the resulting calculated ratio might facilitate estimation of the approximate size of the nuclear region occupied by the nucleolar bodies. The size of nuclear regions occupied by nucleolar bodies decreased during the differentiation and maturation of leukaemic lymphocytes, but was constant for each differentiation or maturation stage. The present study was
unde-taken to provide more information on the approximate size of the nuclear regions occupied by nucleolar bodies in leukaemic granulocytic progenitors. Myeloblasts of established Kasumi 1 and K 562 cell lineages originating from human myeloid leukaemias were convenient models for such study because they represented only one and early differentiation stage of granulocytic progenitors. According to the results, the maximal and mean nucleolar body : maximal and mean nuclear diameter ratios in myeloblasts without heavy nuclear alterations were stable and not markedly influenced by the anti-leukaemic treatment or aging. Thus, the roughly estimated size of nuclear regions occupied by nucleolar bodies in these cells appeared to be similar and stable regardless of aging or antileukaemic treatment. In contrast, the antileukaemic treatment or aging in such myeloblasts induced marked reduction of the nucleolar biosynthetic activity reflected by the decreased number of nucleolar fibrillar centres. and Corresponding author: Karel Smetana
A new application of the parametric anti-resonance is discussed. This phenomenon can be used not only for suppressing self-excited vibration or to reduce the externally excited vibration but also to suppressing self-excited vibration or to reduce the externally excited vibration but also to suppress the parametric resonance when certain conditions are met. Another aim is to stimulate further investigations and the practical applications. and Obsahuje seznam literatury
The aim of this contribution is to present a basic survey of publications dealing with the means of vibration suppression in several kinds of self-excitation. The attention is given to passive and active means using parametric excitation. A special attention is given to the latter and the necessary steps for answering important questions are formulated to initiate further investigation and especially application to real systems. and Obsahuje seznam literatury
Smoking is the most important cardiovascular (CV) risk factor. Stopping smoking halves the CV risk. Every clinician should provide a brief intervention with smokers. Intensive treatment should be available to those who need it. There are 37 Centers for Tobacco Dependence in the Czech Republic, which offer treatment including a psychobehavioral intervention and pharmacotherapy (varenicline, nicotine, bupropion). Czech physicians, pharmacists and nurses are regularly educated about smoking cessation. We describe the results of intensive treatment offered by our centers. Treatment includes screening (1 h), an intervention (2 h), and follow-up visits during the next 12 months. Among 3532 patients, 34.3 % had CO-validated abstinence at 12-months (including 489 patients who attended the screening visit + only the 12-month follow up visit). Among patients who underwent the intervention, the abstinence rate was 38.2 %. The majority of patients who underwent the intervention (N=2470) used some form of pharmacotherapy. After one year, the abstinence rate was 43.4 %, compared to 15.9 % (N=573) without pharmacotherapy. Only 28 % of patients came on the recommendation of a physician. Despite the decrease in CV risk following smoking cessation and the effectiveness of treatment, centers are underutilized., E. Králíková, A. Kmeťová, L. Štěpánková, K. Zvolská, V. Felbrová, S. Kulovaná, Z. Bortlíček, M. Blaha, K. Fraser., and Obsahuje bibliografii
Growth of the tocopherol-deficient vte1 mutant and Col-0 wild type of Arabidopsis thaliana in a sunlit glasshouse revealed both similarities and differences between genotypes. Photosynthetic capacity and leaf mesophyll features did not differ between mutant and wild type. Likewise, the total volume of water conduits (tracheary elements, TEs), sugar conduits (sieve elements, SEs), and sugar-loading cells (companion and phloem parenchyma cells) on a leaf area basis were unaffected by tocopherol deficiency. However, tocopherol deficiency yielded smaller and more numerous minor veins with fewer phloem cells and smaller TEs, resulting in greater ratios of TEs to SEs. The smaller TEs in the vte1 mutant may present a decreased risk for cavitation under high evaporative demand or in response to freezing. In turn, compensation for fewer phloem cells and smaller TEs by more numerous veins may bolster resistance to cavitation at no cost to photosynthetic capacity., J. J. Stewart, W. W. Adams, C. M. Cohu, B. Demmig-Adams., and Obsahuje bibliografické odkazy
We derive the phenomena of Landau damping as a stationary point of entropy functions with Lagrangian methods. The steady states are described inside of some interval of numbers with infinite fuzzy logic controllers. The results are also true for local equilibriums, i.e. for some global non-equilibriums functions.
Cadmium is often detected in areas contaminated by heavy metals and the incidence of this element in dangerous concentrations has been increasing due to anthropogenic activities. The aim of this research was to determine Cd concentrations in tissues, quantify compounds, pigments and enzymes, and to evaluate the gas exchange. Our aim was also to identify components that can modify and contribute to tolerance of Cassia alata against Cd toxicity. We used five Cd concentrations (0, 22, 44, 88, and 132 μM) to validate our hypothesis. The Cd concentrations in tissues of C. alata plants increased significantly, compared with the control treatment, in the following graduated sequence: root > leaf > stem. Progressive enhancement in glutathione (GSH) was verified in plants treated with all Cd concentrations used, when compared with treatment without Cd. Antioxidant enzyme activities presented similar patterns with progressive enhancements, being a desirable characteristic for plants with a potential to hyperaccumulate Cd. Our results suggest that C. alata plants can be used for phytoremediation programs. Their defense mechanism is based on Cd accumulation in roots, coupled with increase in GSH and the efficient activity of antioxidant enzymes that contribute to minimize the oxidative stress and consequently improve the protection of the metabolic machinery., J. R. R. Silva, A. R. Fernandes, M. L. Silva Junior, C. R. C. Santos, A. K. S. Lobato., and Obsahuje bibliografii