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61.
Inflammatory myofibroblastic tumor (IMT) is a pseudosarcomatous lesion occurring in soft tissue and organs. It is known under a wide number of terms, such as inflammatory pseudotumor, plasma cell granuloma, pseudosarcomatous myofibroblastic proliferation. IMT is most commonly located in the lung, while laryngeal location is rarely described. Due to its biology it can be misdiagnosed as a malignant tumor. We present a case of IMT of larynx, recognized in time and treated with laser ablation. Our case demonstrates the importance of timely IMT recognition in order to avoid overtreatment. This diagnosis should also alert clinicians to close follow-up of these patients.  相似文献   
62.
In this work four cationic additives were used to improve the surface activity of lung surfactants, particularly in the presence of bovine serum that was used as a model surfactant inhibitor. Two of those additives were chitosan in its soluble hydrochloride form with average molecular weights of 113 kDa and 213 kDa. The other two additives were cationic peptides, polylysine 50 kDa and polymyxin B. These additives were added to bovine lipid extract surfactant (BLES) and the optimal additive-surfactant ratio was determined based on the minimum surface tension upon dynamic compression, carried out in a constrained sessile drop (CSD) device in the presence of 50 μl/ml serum. At the optimal ratio all the BLES-additive mixtures were able to achieve desirable minimum surface tensions. The optimal additive-surfactant ratios for the chitosan chlorides are consistent with a previously proposed patch model for the binding of the anionic lipids in BLES to the positive charges in chitosan. For the peptides, the optimal binding ratios were consistent with ratios established previously for the binding of these peptides to monolayers of anionic lipids. The optimal formulation containing these peptides were able to reach low minimum surface tension in systems containing 500 μl/ml of serum, matching the effectiveness of a lung surfactant extract that had not undergone post-separation processes and therefore contained all its proteins and lipids (complete lung surfactant).  相似文献   
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64.
Attention deficit hyperactivity disorder (ADHD) belongs to the neurodevelopmental disorders characterized by impulsivity, distractibility and hyperactivity. In the pathogenesis of ADHD genetic and non-genetic factors play an important role. It is assumed that one of non-genetic factors should be oxidative stress. Pycnogenol, an extract from the pine bark, consists of bioflavonoids, catechins, procyanidins and phenolic acids. Pycnogenol acts as powerful antioxidant, chelating agent; it stimulates the activities of some enzymes, like SOD, eNOS, and exhibits other biological activities. AIM: The aim of this randomized, double-blind, placebo-controlled trial was to investigate the influence of administered Pycnogenol or placebo on the level of reduced (GSH) and oxidized (GSSG) glutathione in children suffering from ADHD and on total antioxidant status (TAS). This is the first investigation of the redox glutathione state in relation to ADHD. RESULTS: One month of Pycnogenol administration (1 mg/kg body weight/day) caused a significant decrease in GSSG and a highly significant increase in GSH levels as well as improvement of GSH/GSSG ratio in comparison to a group of patients taking a placebo. TAS in children with ADHD was decreased in comparison with reference values. Pycnogenol administration normalizes TAS of ADHD children.  相似文献   
65.
We have developed S. cerevisiae as a model system for mechanistic studies of the 26S proteasome. The subunits of the yeast 19S complex, or regulatory particle (RP), have been defined, and are closely related to those of mammalian proteasomes. The multiubiquitin chain binding subunit (S5a/Mcb1/Rpn10) was found, surprisingly, to be nonessential for the degradation of a variety of ubiquitin-protein conjugates in vivo. Biochemical studies of proteasomes from rpn10 mutants revealed the existence of two structural subassemblies within the RP, the lid and the base. The lid and the base are both composed of 8 subunits. By electron microscopy, the base and the lid correspond to the proximal and distal masses of the RP, respectively. The base is sufficient to activate the 20S core particle for degradation of peptides, but the lid is required for ubiquitin-dependent degradation. The lid subunits share sequence motifs with components of the COP9/signalosome complex, suggesting that these functionally diverse particles have a common evolutionary ancestry. Analysis of equivalent point mutations in the six ATPases of the base indicate that they have well-differentiated functions. In particular, mutations in one ATPase gene, RPT2, result in an unexpected defect in peptide hydrolysis by the core particle. One interpretation of this result is that Rpt2 participates in gating of the channel through which substrates enter the core particle.  相似文献   
66.
1,2,3,5-tetra-O-acetyl-4-thio-beta-L-ribofuranose (13) was synthesized by an improved five-step sequence starting from methyl alpha-D-lyxopyranoside. Compound 13 was then converted to the corresponding L-4'-thionucleosides 4-6 and 19 by a modified Vorbrüggen procedure. All of these nucleoside analogues were tested for their antitumour activity in vitro.  相似文献   
67.
FRTL-5 cell line is a cloned epithelial follicular cell line from Fischer rat thyroids. This cell line expresses many of the thyroid differentiated markers in vitro. Their growth and function depend on thyrotropin (TSH) as the main regulatory hormone. In this astereological analysis, the authors concentrate on FRTL-5 nuclei as the most vulnerable part of the cell. Using morphometrical variables, they wished to discover the morphologically identifiable sign of transformation of FRTL-5 cells after irradiation and to study the effect of different TSH concentrations. FRTL-5 cells were grown in a medium of 4 different concentrations of TSH (0, 0.1, 1, 10 mU/ml) and irradiated with 0 Gy, 2 Gy, and 4 Gy. The results showed that the nuclear-cytoplasmic ratio decreases after irradiation with doses of 4 Gy or if TSH was included in the medium. The nuclear maximum diameter of FRTL-5 cells increased with higher concentrations of TSH more obviously after irradiation with 4 Gy than with 2 Gy. On the basis of astereological analysis, it was concluded that different concentrations of TSH and irradiation exert an effect especially upon FRTL-5 cell nuclei. The possible transformation of FRTL-5 cells after culturing in TSH medium and after irradiation could be confirmed by injection into an animal of the Fischer strain.  相似文献   
68.
Two chromosome numbers n=54, n=55 were found inBolboschoenus plants studied from Central Europe (Czech Republic, Slovakia, Hungary, Poland) and coastal regions of Europe (the Netherlands, Sweden). The number n=55 is typical forB. maritimus subsp.maritimus with narrow fruits and mostly also forB. maritimus subsp.compactus; the number n=54 characterizesB. planiculmis auct. The morphological type ofB. maritimus subsp.maritimus with wide fruits represents a stable taxon occurring in freshwater habitats throughout Europe. Its variation in chromosome numbers (both n=54, n=55) indicates a possible hybrid origin, probably resulting from hybridization betweenB. maritimus subsp.maritimus with narrow fruits andB. planiculmis auct. Spontaneous hybridization betweenBolboschoenus taxa in the regions with mixed populations may explain the origin of the intermediate morphological and anatomical characters of plants from some localities and the deviations in chromosome numbers.  相似文献   
69.
The distribution, total frequency of occurrence, regional differences and habitat conditions of diploid and triploidButomus umbellatus L. were studied in the Czech and Slovak Republics. Triploids are more frequent than diploids, with numerous localities in warm lowland regions in river floodplains. Diploids were found primarily in the South Bohemian T?eboň basin, outside the warm regions. The two cytotypes do not differ in dependence on water depth. Triploids occur more in habitats with more alkaline and base-rich soils. Considering the total distribution of both cytotypes in the area studied, triploidB. umbellatus appears to be more successful than its diploid progenitor, owing to its wider habitat range and superiority in vegetative reproduction.  相似文献   
70.
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