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8242. Experimental models of hyperlipoproteinemia and atherosclerosis
- Creator:
- Rudolf Poledne and Jurčíková-Novotná, L.
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, lipoproteiny, ateroskleróza, lipoproteins, atherosclerosis, atherosclerosis-models, 14, and 612
- Language:
- English
- Description:
- The first experimental model of atherosclerosis (in rabbits) is more than hundred years old. Several animal species have bee n used to produce hyperlipoproteine mia and possible atherosclerosis. The gene manipulation produced the most used models recently. This review acknowledges the extensive study of atherosclerotic changes in experimental models of hyperlipoprotein emia and at herosclerosis to come to light thus far and the purpose here is not only to summariz e the published data but also to try to add some details of our experience in using these models. In addition to rabbit (the old but also improved model by reno-vascular hy pertension) dog, birds, pig, hamster, mice, rat and non-human primate’s animal models are described. The gene manipulation produced the most used models two decades ago. Germline genetically engineered (without apoE or LDL receptor genes) animals have beco me the most used models producing atherosclerotic changes in the aorta. Recent new models also producing atherosclerotic changes but without germline genetic manipulation are also described., R. Poledne, L. Jurčíková-Novotná., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8243. Experimental recognition of loading character of transtibial prosthesis
- Creator:
- Paloušek, David, Návrat, Tomáš, Rosický, Jiří, Krejčí, Petr, and Houfek, Martin
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- transtibial prosthesis, strain gange, and loading character of prosthesis
- Language:
- English
- Description:
- This paper deals with experimental simulation of mechanical properties of transtibial prosthesis. Artificial limb allows patient standing and moving without of using others supporting devices. Therefore, patient returns back to common and active life. Design and prosthesis properties decide about comfort, safeness and reliability of prosthesis. The article summarizes a conclusion of preliminary experiment, which was performed to measurement procedure of prosthesis strain (for real loading of straight walking, downhill walking and downstairs walking) and data processing. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8244. Experimental research of chaos in drive systems
- Creator:
- Kratochvíl, Ctirad, Heriban, Pavel, Houfek, Martin, Houfek, Lubomír, and Švéda, Petr
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chaos, dynamical system, drive systems, and nonlinear systems
- Language:
- English
- Description:
- Chaos can be defined on bounded-state behaviour that is not equilibrium solution or a periodic solution or a quasiperiodic solution. The article is focused on analysis of dynamic properties of controlled drive systems and also on bifurcation of steady states and possible occurrence of chaotic behaviour. The purpose of this article is to provide an elementary introduction to the subject of chaos in the electromechanical drive systems. In this article, we explore chaotic solutions of maps and continuous time systems. The attractor associated with chaotic motion in state space is not a simple geometrical object like a finite number of points, a closed curve or a torus. Chaotic attractor is complex geometrical object that posses fractal dimensions. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8245. Experimental rig for simulation of hydromechanical system with energy regeneration
- Creator:
- Klapka, Milan, Nevrlý, Josef, and Panáček, Tomáš
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- hydrostatic drive, energy regeneration, and heavy vehicles
- Language:
- English
- Description:
- The article deals with design of the experimental rig with hydromechanical system and enegy regeneration. Suggested rig is also scaled model of the heavy vehicle hydrostatic drive. The energy regeneration circuit is connected in the series with the hydraulic circuit of the drive. The test rig enables verification of mathematical model of the heavy vehicle drive and optimization of the operational parameters of the drive to achieve high efficiency of regeneration. Such procedures will be extremely difficult to perform directly on the vehicle. and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8246. Experimental studies on the development of Contracaecum rudolphii (Nematoda: Anisakidae) in copepod and fish paratenic hosts
- Creator:
- Moravec, František
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- parasitic nematode, Contracaecum, cormorant, Phalacrocorax, development, paratenic host, copepod, and fish
- Language:
- English
- Description:
- The larval development of the nematode Contracaecum rudolphii (Rudolphi, 1819), a common parasite of the proventriculus of cormorants, was experimentally studied. Within the eggs cultivated in freshwater under laboratory temperatures of 20-22 °C, the developing larva undergoes two moults on days 4-5, attaining the third larval stage. Most of the ensheathed third-stage larvae, 291-457 µm long, hatch spontaneously from egg shells on days 5-6. Experiments have indicated that hatched ensheated third-stage larvae and those still inside egg capsules are already infective to copepods and fishes, which both can be considered paratenic (metaparatenic) hosts. Five copepod species, Acanthocyclops vernalis, Cyclops strenuus, Ectocyclops phaleratus, Eucyclops serrulatus and Megacyclops viridis, the isopod Asellus aquaticus and small carps Cyprinus carpio were infected by feeding them these larvae. In addition, 9 fish species, Alburnoides bipunctatus, Anguilla anguilla, Barbatula barbatula, Cyprinus carpio, Gobio gobio, Perca fluviatilis, Phoxinus phoxinus, Poecilia reticulata and Tinca tinca, were successfully infected by feeding them copepods previously infected with C. rudolphii third-stage larvae. In fishes, larvae from copepods penetrate through the intestinal wall to the body cavity, where, in a few weeks, they become encapsulated; the larvae substantially grow in fish, attaining the body length up to 4.87 mm. In carp fry, the nematode third-stage larvae survived for about 15 months (up to 18 months in fish infected directly, i.e., without copepods). One small cormorant (Phalacrocorax carbo sinensis) was successfully infected by feeding it with copepods harbouring C. rudolphii third-stage larvae.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8247. Experimental study on pathogenic potential of six Acanthamoeba strains isolated from fish
- Creator:
- Veverková, Marie, Dyková, Iva, and Pecková, Hana
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- English
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8248. Experimental study on the rheological behaviour of coal ash slurries
- Creator:
- Assefa, K.M. and Kaushal, D.R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- coal ash slurry, Newtonian fluid, yield stress, plastic viscosity, and relative viscosity
- Language:
- Slovak
- Description:
- Extensive experimental investigations were carried out to evaluate the rheological behaviour of fly ash (FA) slurry without and with the addition of bottom ash (BA) and BA slurry without and with the addition of FA. The FA slurries exhibited Bingham behaviour at solid mass concentrations ranging from 60-65% and mixing proportions from 10- 40%. A substantial reduction in yield stress was observed except for mixing proportion of 40% on which the yield stress and viscosity were increased drastically for all solid concentrations. Hence, it can be concluded that the yield stress and viscosity of FA slurry were very much influenced by adding BA up to the mixing proportion of 30%. The rheological behaviour of BA slurries with and without the addition of FA in proportions of 10-50% was investigated and exhibited Newtonian behaviours for solid mass concentrations ranging from 30-50% without and with the addition of FA. The viscosity increases with increasing the solid concentrations and proportion of FA. Based on these experimental data, a correlation was developed to predict the relative viscosity of BA slurries as a function of solid volume fraction and FA mass proportion of 0-50% and the RMSE and R2 values showed good agreement between the experimental and the predicted data.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8249. Experimental transmission of Caryospora kutzeri (Apicomplexa: Eimeriidae) by rodent hosts
- Creator:
- Volf, Jiří, Modrý, David, and Koudela, Břetislav
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Coccidia, Eimeriidae, Caryospora kutzeri, Falco tinnunculus, transmission, and paratenic host
- Language:
- English
- Description:
- Four laboratory-hatched European kestrels Falco tinnunculus L. were fed on laboratory mice and common voles Microtus arvalis Pallas previously inoculated with different doses of sporulated oocysts of Caryospora kutzeri Böer, 1982. Two kestrels that were fed infected mice shed C. kutzeri oocysts 6 days after ingesting murine tissues. To compare direct and indirect transmissions, two of the kestrels were subsequently directly inoculated with 105 sporulated C. kutzeri oocysts and became patent on days 8 and 9 and shed caryosporan oocysts up to day 25 post inoculation. Additionally, four mice were inoculated with 106 oocysts in order to examine mouse tissues for the presence of developmental stages of C. kutzeri. No coccidian stages were found in the tissues of inoculated mice. The experiment showed that developmental stages of C. kutzeri are able to survive in mouse tissues and cause infection of suitable host after their ingestion.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8250. Experimental transmission of Sparicotyle chrysophrii (Monogenea: Polyopisthocotylea) to gilthead seabream (Sparus aurata) and histopathology of the infection
- Creator:
- Sitjà-Bobadilla, Ariadna and Alvarez-Pellitero, Pilar
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Monogenea, gills, ectoparasites, haematology, anaemia, and Sparidae
- Language:
- English
- Description:
- The polyopisthocotylean Sparicotyle chrysophrii (Van Beneden et Hesse, 1863) was experimentally transmitted to gilthead seabream (Sparus aurata L.) by exposure to eggs (EGT) and by cohabitation with naturally parasitized fish (CT). In EGT trials, the infection was successfully transmitted by introducing containers with monogenean eggs in the fish tanks, with the highest infection level (85.7% prevalence, 3.3 mean intensity) achieved at 6 weeks post exposure (p.e.) to the infection dose of 650 eggs per tank. In CT trials, the progression of the infection was faster and reached higher levels than in EGT. When using small fish juveniles (30 g) (CT-2), infection reached 100% prevalence (mean intensity 8 monogeneans/fish) at 5 weeks p.e., but no eggs could be found in the fish even 10 weeks p.e. By contrast, when larger juveniles (150 g) were used (CT-1), infection levels were lower, but mature adults with eggs were detected starting from 8 weeks p.e. The effect of the parasite on the condition factor, haematocrit, haemoglobin concentration (Hb), red blood cell counts, mean corpuscular haemoglobin concentration (MCHC), mean corpuscular haemoglobin content (MCH) and mean cellular volume (MCV) of infected fish was studied in CT trials. The infection produced hypochromic anaemia, since Hb concentration significantly decreased at 5 and 10 weeks p.e. in CT-2 and at 8 weeks p.e. in CT-1. MCHC was significantly lower in parasitized than in control fish at 5 and 8 weeks p.e. in CT-2 and CT-1, respectively. Also in CT-1, MCH was lower and circulating immature erythrocytes, granulocytes and plasma cells were higher in infected fish than in control ones at 8 weeks p.e. The histopathological effects of the monogenean on the gills of naturally infected fish consisted of lamellar shortening, clubbing and synechiae. The proliferation of the epithelial tissue produced fusion of secondary lamellae, and abundant chloride cells were observed.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public