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28622. US relations with Eastern Europe :
- Creator:
- Lakatos, Artúr,
- Type:
- text and studie
- Subject:
- Mezinárodní vztahy, světová politika, vztahy USA-Evropa, diplomacie, geopolitika, USA, světové dějiny od r. 1945 do současnosti, and zahraniční politika, mezinárodní vztahy
- Language:
- English
- Description:
- Americké vztahy s východní Evropou. Skutečnost a vyhlídky.
- Rights:
- unknown
28623. Use of 3D geometry modeling of osteochondrosis-like iatrogenic lesions as a template for press-and-fit scaffold seeded with mesenchymal stem cells
- Creator:
- Petr Krupa, Pavel Kršek, Javorník, M., Otto Dostál, Robert Srnec, Dušan Usvald, Pavel Proks, Helga Kecová, Evžen Amler, Josef Jančář, Peter Gál, Ladislav Plánka, and Alois Nečas
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, chrupavka, mezenchymální kmenové buňky, cartilage, mesenchymal stem cells, CT imaging, tissue segmentation, joint resurfacing, miniature pig, 14, and 612
- Language:
- English
- Description:
- Computed tomography (CT) is an effective diagnostic modality for three-dimensional imaging of bone structures, including the geometry of their defects. The aim of the study was to create and optimize 3D geometrical and real plastic models of the distal femoral component of the knee with joint surface defects. Input data included CT images of stifle joints in twenty miniature pigs with iatrogenic osteochondrosis-like lesions in medial femoral condyle of the left knee. The animals were examined eight and sixteen weeks after surgery. Philips MX 8000 MX and View workstation were used for scanning parallel plane cross section slices and Cartesian discrete volume creation. On the average, 100 slices were performed in each stifle joint. Slice matrices size was 512 x 512 with slice thickness of 1 mm. Pixel (voxel) size in the slice plane was 0.5 mm (with average accuracy of ± 0.5 mm and typical volume size 512 × 512 × 100 voxels). Three-dimensional processing of CT data and 3D geometrical modelling, using interactive computer graphic system MediTools formerly developed here, consisted of tissue segmentation (raster based method combination and 5 % of manual correction), vectorization by the marching-cubes method, smoothing and decimation. Stifle- joint CT images of three individuals of different body size (small, medium and large) were selected to make the real plastic models of their distal femurs from plaster composite using rapid prototyping technology of Zcorporation. Accuracy of the modeling was ± 0.5 mm. The real plastic models of distal femurs can be used as a template for developing custom made press and fit scaffold implants seeded with mesenchymal stem cells that might be subsequently implanted into iatrogenic joint surface defects for articular cartilage-repair enhancement., P. Krupa, P. Kršek, M. Javorník, O. Dostál, R. Srnec, D. Usvald, P. Proks, H. Kecová, E. Amler, J. Jančář, P. Gál, L. Plánka, A. Nečas., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
28624. Use of a right ventricular continuous flow pump to validate the distensible model of the pulmonary vasculature
- Creator:
- Vanden Eynden, F. , Segers, P., Bové, T. , De Somer, F., El Oumeiri, B., and Van Nooten, G.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Pulmonary circulation, Distensibility, Assist device, and Vascular resistence
- Language:
- English
- Description:
- In the pulmonary circulation, resistive and compliant properties overlap in the same vessels. Resistance varies nonlinearly with pressure and flow; this relationship is driven by the elastic properties of the vessels. Linehan et al. (1982) correlated the mean pulmonary arterial pressure and mean flow with resistance using an original equation incorporating the distensibility of the pulmonary arteries. The goal of this study was to validate this equation in an in vivo porcine model. In vivo measurements were acquired in 6 pigs. The distensibility coefficient (DC) was measured by placing piezo-electric crystals around the pulmonary artery (PA). In addition to experiments under pulsatile conditions, a right ventricular (RV) bypass system was used to induce a continuous pulmonary flow state. The Linehan's equation was then used to predict the pressure from the flow under continuous flow conditions. The diameter-derived DC was 2.4 %/mmHg (±0.4 %), whereas the surface area-based DC was 4.1 %/mmHg (±0.1 %). An increase in continuous flow was associated with a constant decrease in resistance, which correlated with the diameter-based DC (r=-0.8407, p=0.044) and the surface areabased DC (r=-0.8986, p=0.028). In contrast to the Linehan’s equation, our results showed constant or even decreasing pressure as flow increased. Using a model of continuous pulmonary flow induced by an RV assist system, pulmonary pressure could not be predicted based on the flow using the Linehan’s equation. Measurements of distensibility based on the diameter of the PA were inversely correlated with the resistance.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28625. Use of Aguieira Dam by Eurasian otters in Central Portugal
- Creator:
- Pedroso, Nuno M., Sales-Luís, Teresa, and Santos-Reis, Margarida
- Type:
- article and TEXT
- Subject:
- Lutra lutra, reservoir, spatial use, marking behaviour, diet, and tributaries
- Language:
- English
- Description:
- The construction of dams is a significant environmental issue due to its impacts on native fish populations and riparian animals and habitats. The response of otters Lutra lutra Linnaeus, 1758 to such disturbances was evaluated using the Aguieira reservoir (Central Portugal) and its associated tributaries as a model. Visiting rates suggested the presence of resident otters, both in the reservoir and in two of the tributaries. There was a significant negative influence of water level and precipitation in the number of spraints found around the reservoir. Nevertheless, marking behaviour was positively related to substrate and negatively related to vegetation cover, though these variables explained only a small amount of variation in otter signs. In the tributaries, although precipitation also negatively affected the number of otter signs found, the availability of rocks in the riverbed and the presence of refuge had a positive influence in marking behaviour. Prey composition and abundance differed between reservoir and tributaries, but the main otter prey in both systems was the pumpkinseed, which is very abundant in the reservoir. Results demonstrate that otters regularly use the Aguieira reservoir, which provides a good prey base, and the associated tributaries, which provide shelter.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
28626. Use of allogenic stem cells for the prevention of bone bridge formation in miniature pigs
- Creator:
- Ladislav Plánka, Alois Nečas, Robert Srnec, Petr Raušer, David Starý, Josef Jančář, Evžen Amler, Eva Filová, Jana Juhásová, Leoš Křen, and Petr Gál
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie, poranění, physiology, wounds and injuries, růstová ploténka, fysis, deformace končetiny, mesenchymální kmenové buňky, growth plate, physis, limb deformity, mesenchymal stem cells, 14, and 612
- Language:
- English
- Description:
- This study appears from an experiment previously carried out in New Zealand white rabbits. Allogenic mesenchymal stem cells (MSCs) were transplanted into an iatrogenically-created defect in the lateral section of the distal physis of the left femur in 10 miniature pigs. The right femur with the same defect served as a control. To transfer MSCs, a freshly prepared porous scaffold was used, based on collagen and chitosan, constituting a compact tube into which MSCs were implanted. The pigs were euthanized four months after the transplantation. On average, the left femur with transplanted MSCs grew more in length (0.56±0.14 cm) compared with right femurs with physeal defect without transplanted MSCs (0.14 ± 0.3 cm). The average angular (valgus) deformity of the left femur had an angle point of 0.78°, following measurement and X-ray examination, whereas in the right femur without transplantation it was 3.7°. The initial results indicate that preventive transplantation of MSCs into a physeal defect may prevent valgus deformity formation and probably also reduce disorders of the longitudinal bone growth. This part of our experiment is significant in the effort to advance MSCs application in human medicine by using pig as a model, which is the next step after experimenting on rabbits., L. Plánka ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
28627. use of artificial nest-boxes by Apodemus sylvaticus dichrurus in Sicily
- Creator:
- Sarà, Maurizio
- Type:
- article and TEXT
- Subject:
- wood mouse, arboreal activity, and Mediterranean woodlands
- Language:
- English
- Description:
- Reports of wood mouse arboreality are rather scarce outside Britain. I reviewed and analysed 267 visits and 16,456 checks of glirids artificial nest-boxes mounted on trees, in twelve sample areas of Meso- and Supra-Mediterranean woodlands (Sicily, 1995–2005). The wood mouse was recorded only 65 times (0.395%) using the artificial nest-boxes in nine sample areas, and based on this low frequency, the wood mouse can be considered as an occasional dweller of artificial nest-boxes. The resource selection index allowed checking the use respect to the availability of nest-boxes placed at different heights. These were likely reached by climbing the dense understorey and low tree branches up to 5 m, but nest-boxes in the two lower classes (0.5–1.0 and 1.1–1.5 m) were used more than those in the two higher classes (1.6–2.0 and 2.1–5.0 m). ANOVA results suggested that the box use was not related to any particular habitat or sample area feature, and it was slightly more pronounced from March to May. Regardless of their age and sex, individuals mostly exploited nest-boxes placed near the ground (0.5–1.5 m) and generally for 2–3 months. Nonetheless, cases of consecutive use for longer periods and instances of reproduction inside nest-boxes showed that some individuals extended their home range also to the vertical dimension.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
28628. Use of bio-degradable stents for the treatment of refractory benign gastrointestinal stenoses
- Creator:
- Rejchrt, Stanislav, Bureš, Jan, Brožík, Jan, and Kopáčová, Marcela
- Format:
- braille, text, and regular print
- Type:
- model:article, article, Text, práce podpořená grantem, and TEXT
- Subject:
- vstřebatelné implantáty, dospělí, zvířata, biokompatibilní materiály, Crohnova nemoc--chirurgie--komplikace, gastrointestinální endoskopie, ženské pohlaví, lidé, střevní obstrukce, mužské pohlaví, polymery, and stenty
- Language:
- English
- Description:
- Bio-degradable stents are be made of different synthetic polymers (like polylactide or polyglycolide) or their co-polymers (polydioxanone). They can be used for treating benign stenoses of the small and large intestine, particularly in Crohn’s disease. Endoscopic introduction of bio-degradable stents into small and large intestinal stenoses is feasible and relatively simple. Initial results are encouraging and the complication rate is low. However, there are still some difficulties that need to be overcome. The rate of early stent migration is still rather high (up to one third of patients). This might be solved by changes in the shape or rigidity of the stents as well as by further improvement in the design. Proof of long-term efficacy and safety requires further studies., Stanislav Rejchrt, Jan Bureš, Jan Brožík, Marcela Kopáčová, and Literatura 52
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
28629. Use of bone and otolith measures for size-estimation of fish in predator-prey studies
- Creator:
- Tarkan, Ali Serhan, Gürsoy Gaygusuz, Çiğdem, Gaygusuz, Özcan, and Acipinar, Hasan
- Type:
- article and TEXT
- Subject:
- diet analysis, prey size estimation, piscivorous predators, and cyprinids
- Language:
- English
- Description:
- To estimate the size of fish taken as prey by piscivorous predators, linear or non-linear relationships between bone measures (pharyngeal, opercula, cleithra, anal and dorsal spine bones, otoliths) and body length were elaborated for eleven Eurasian cyprinid fish species captured in three lakes of Turkey: rudd Scardinius erythrophthalmus, Baltic vimba Vimba vimba, Danube bleak Chalcalburnus chalcoides, gibel carp Carassius gibelio, roach Rutilus rutilus, silver bream Blicca bjoerkna, common carp Cyprinus carpio, chub Leuciscus cephalus, Dnieper chub Petroleuciscus borysthenicus, tench Tinca tinca and tarek Alburnus tarichi (endemic species for Lake Van). All calculated regressions were highly significant, with coefficients of determination >81% in most of cases. The results suggest that the biometric relationships between fish length and some bones (pharyngeal, opercula, cleithra) are well suited for use in prey-predator studies of all the studied species, but otoliths and the dorsal and anal spines can be used for some fish species only (rudd, Baltic vimba, roach, silver bream, gibel carp).
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
28630. Use of chemical dosimetry for comparison of ultrasound and ionizing radiation effects on cavitation
- Creator:
- Bohumil Kratochvíl and Vojtěch Mornstein
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, ultrazvuk, ionizující záření, ultrasound, ionizing radiation, cavitation effects, gray equivalent dose, dosimetry, 14, and 612
- Language:
- English
- Description:
- A comparison of the effects of ultrasound produced by low- and high-frequency ultrasonic apparatuses upon biological systems is one of the basic problems when studying ultrasound cavitation effects. One possibility for how to compare these effects is the indirect method which uses well-known physical quantities characterizing the interaction of ionizing radiation with matter and which also converts these quantities to one common physical quantity. The comparison was performed with two methods applied to the chemical dosimetry of ionizing radiation. The first method employed a twocomponent dosimeter which is composed of 50 % chloroform and 50 % re-distilled water (i.e. Taplin dosimeter). The other method used a modified iodide dosimeter prepared from a 0.5 M potassium iodide solution. After irradiation or ultrasound exposure, measurable chemical changes occurred in both dosimeters. The longer the exposure, the greater the chemical changes. These effects are described by the relationship of these changes versus the exposure times in both dosimeters. The UZD 21 ultrasonic disintegrator (with a frequency of 20 kHz, 50 % power output) was used as a lowfrequency ultrasound source, and the BTL-07 therapeutic instrument (with a frequency of 1 MHz and intensity of 2 W/cm2) was used as a high-frequency cavitation ultrasound source. For comparison, a 60Co gamma source was applied (60Co, gamma energies of 1.17 and 1.33 MeV, activity of 14 PBq). Results of this study have demonstrated that the sonochemical products are generated during exposure in the exposed samples of both dosimeters for all apparatuses used. The amount of these products depends linearly upon the exposure time. The resulting cavitation effects were recalculated to a gray-equivalent dose (the proposed unit is cavitation gray [cavitGy]) based on the sonochemical effects compared to the effects of ionizing radiation from the 60Co source., B. Kratochvíl, V. Mornstein., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public