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25552. Variabilita plicních laloků a jejich průmět na prostém snímku
- Creator:
- Sedláčková, Zuzana, Čtvrtlík, Filip, and Heřman, Miroslav
- Format:
- print, text, and regular print
- Type:
- model:article, article, Text, práce podpořená grantem, and TEXT
- Subject:
- plíce--anatomie a histologie--radiografie, tomografie rentgenová počítačová--metody--využití, statistika jako téma, neparametrická statistika, anatomie srovnávací--metody--statistika a číselné údaje, rentgendiagnostika hrudníku, pleura--anatomie a histologie--radiografie, lidé, dospělí, lidé středního věku, staří, ženské pohlaví, mužské pohlaví, rozsah plicních laloků, prosté snímky, průmět plicních laloků, lokalizace interlobií, and plicní léze
- Language:
- Czech and English
- Description:
- Cíl: Cílem bylo určit a zobrazit typický rozsah plicních laloků a jeho krajní varianty. Metodika: Z 250 HRCT vyšetření hrudníku dospělých pacientů bez nálezu výraznější patologie jsme zjistili varianty rozsahu plicních laloků a následně jsme typické polohy a jejich krajní varianty promítli na prosté snímky. Výsledky: Na levé straně byla hranice mezi plicními laloky nejvýše dorzálně nejčastěji u čtvrtého žebra (45 %), s rozsahem od druhého po osmé žebro. Laterodorzálně bylo dolní rozhraní nejčastěji v úrovni šestého žebra (52 %), s rozsahem od čtvrtého po osmé žebro. Vpravo byla hranice mezi horním a dolním plicním lalokem nejčastěji nejvýše u pátého žebra (49 %), s rozsahem od čtvrtého po osmé žebro. Laterodorzálně byla dolní hranice nejčastěji v úrovni šestého žebra (50 %), s rozsahem od čtvrtého po osmé žebro. Vedlejší interlobium probíhalo nejčastěji v úrovni ventrálního konce čtvrtého žebra. Závěr: Průmět plicních laloků na snímcích se mezi jednotlivými osobami poměrně významně liší. I při kombinaci dvou projekcí jsou v obou plicích velké oblasti, kde se mohou překrývat průměty laloků. Vzhledem k velké variabilitě polohy interlobií snímky často neumožňují spolehlivou lokalizaci plicních lézí do laloků., Aim: To determine and depict typical extend of lung lobes and its border variants. Methods: HRCT examinations of the lung in 250 adult patients without major pathology were assessed to find out variants of lung lobes localizations. Afterwards we projected typical localizations and their extreme variants on the chest X-rays. Results: On the left side, the most frequent uppermost localization of the border between lung lobes was posteriorly at the fourth rib (45%), range from the second to the eighth rib. Posterolaterally the inferior border was most frequently at the sixth rib (52%), range from the fourth to the eighth rib. On the right side, the most frequent uppermost localization of the border between upper and lower lung lobes was posteriorly at the fifth rib (49%), range from the fourth to the eighth rib. Posterolaterally the inferior border was most frequently at the sixth rib (50%), range from the fourth to the eighth rib. Minor fissure was most frequently located at the level of anterior part of the fourth rib. Conclusion: The projection of lung lobes on the x-rays is considerably different among individuals. Even with two projections there remain extensive areas in both lungs, where the demarcations of lobes overlay each other. Due to the high variability of the position of interlobar fissures, x-rays often do not provide reliable localization of lung lesions into the lobes., Zuzana Sedláčková, Filip Čtvrtlík, Miroslav Heřman, and Literatura
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
25553. Variability along a latitudinal gradient in the chiasma frequency and morphological characters of Dichroplus pratensis (Orthoptera: Acrididae)
- Creator:
- Bidau, Claudio J. and Martí, Dardo
- Type:
- article, model:article, and TEXT
- Subject:
- Central-marginal distribution, chiasmata, Dichroplus, latitudinal gradient, morphological variability, recombination, and Robertsonian translocation
- Language:
- English
- Description:
- The grasshopper Dichroplus pratensis Bruner is polymorphic and polytypic for a complex Robertsonian system. In this species, centric fusions induce changes in number and position of chiasmata, and thus potentially affect intrachromosomal genetic recombination and genetic variability. Males and females, from 23 populations covering most of the geographic range of the species and spanning 22 degrees of latitude, were studied. We analyzed chiasma frequency in relation to variability in six exomorphological characters. The chromosomal polymorphisms of D. pratensis are widely geographically distributed, and show a central-marginal pattern, in which the central populations (those occupying the ecologically optimal habitats) have high mean frequencies of different fusions per individual (F) of up to F = 3.00 and total chiasma frequencies as low as XT = 8.98 per cell, while those near the margins of the distribution (central Patagonia and the Andes) have very low levels of chromosomal polymorphisms [down to F = 0.00 in most geographically marginal locations), monomorphic karyotypes and high chiasma frequencies (XT = 11.66, in the southernmost (Rada Tilly, 45°57´S) and XT = 12.01 in the northernmost population (Volcán, 23°55´S)]. Increasing chiasma frequencies towards the margins of the range are positively and significantly correlated with increasing levels of morphological variability. The decrease in fusion polymorphism and the consequent increase in genetic recombination (both inter- and intrachromosomal) in the marginal areas, is a result of natural selection favouring higher levels of variability, which could be adaptive in ecologically harsher and changing environments.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
25554. Variability and differences in the skulls of the common hamster (Cricetus cricetus) from several areas in Central Europe and from different time periods
- Creator:
- Stefen, Clara
- Type:
- article, model:article, and TEXT
- Subject:
- subspecies C.c. canescens, Thuringia, Saxony-Anhalt, Austria, Belgium, the Netherlands, and discriminant analyses
- Language:
- English
- Description:
- The craniometric variability of skulls of the common hamster (Cricetus cricetus) from different countries (Belgium, the Netherlands, Austria, Germany) and different regions within Germany was studied. The aim was to study the variability in different regions and to see if differences between populations exist now and might have existed in former times also. The discriminant analyses were performed for females and males separately. The material was assigned to three different age classes and tests were attempted with all age classes. For the largest sample from Saxony-Anhalt, differences could also be observed between the three selected time periods (1900-1930, 1931-1960 and 1961-1990). Discriminant analyses were performed by keeping the sexes, age classes, and time periods separate wherever the material allowed for it. Regional samples differed to some degree (depending on the set of samples used). Particularly the samples from Austria, Belgium, and the Netherlands were more offset from the German samples; nevertheless, some overlap existed for the males of the third time period. The position of the small sample from the Rhineland was ambiguous in the different discriminant analyses but seemed rather to fall within the range of other German samples and not clearly in-between the German and the Dutch/Belgian samples. Overall variability, changes with time, and possible yearly fluctuations, as described in the literature, influenced the results and overlaid existing regional differences. The existence of a western subspecies could not be supported. The lack of substantial numbers of specimens illustrated the importance of collecting even the common species at all times for future research.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
25555. Variability and systematic status of Zonorchis clathratum (Trematoda: Dicrocoeliidae), a parasite of swifts and swallows
- Creator:
- Sitko, J.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Dicrocoeliidae, Zonorchis, and swifts and swallows
- Language:
- English
- Description:
- The morphometrical variability of Zonorchis clalhraium (Deslongschamps, 1824) from Apus apus in the Czech Republic, Z. rutshurensis (Baer, 1959) from Apus cajffer streubeli and Z. dureni Vercammen-Grandjean, 1960 from Hirundo ni-grita in Congo was studied. Zonorchis rulshurensis and Z dureni are considered to be synonyms of Z. clathratum. Lyperosomum oswuldoi Travassos, 1919 sensu Jaroń, 1969 is considered to beZ. clathratum, and L. clathratum (Deslongschamps, 1824) sensu Jaroń, 1969 is considered to be Stromitremu koschewnikovi (Skryabin et Massino, 1925).
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
25556. Variability in the karyotypes, testes and ovaries of planthoppers of the families Issidae, Caliscelidae, and Acanaloniidae (Hemiptera: Fulgoroidea)
- Creator:
- Maryańska-Nadachowska, Anna, Kuznetsova, Valentina, Gnezdilov, Vladimir, and Drosopoulos, Sakis
- Type:
- article, model:article, and TEXT
- Subject:
- Hemiptera, Fulgoroidea, Issidae, Caliscelidae, Acanaloniidae, karyotypes, holokinetic chromosomes, testes, ovaries, evolution, and systematics
- Language:
- English
- Description:
- The aim of this study was to obtain information on the karyotypes, testes and ovaries of three fulgoroid families, mainly in the Issidae but also in the Caliscelidae and Acanaloniidae. For the Issidae, the data is for 19 species belonging to 11 genera of the subtribes Issina (2 species, 1 genus), Hysteropterina (14 species, 9 genera) and Agalmatiina (3 species, 2 genera) of the tribe Issini. The male karyotypes are shown to be quite uniform across the tribe, with 2n = 26 + X in all species studied except Latilica maculipes (Melichar, 1906) with 2n = 24 + X. The modal karyotype, 2n = 26 + X, matches the most probable ancestral state in the Fulgoroidea. In the majority of cases the number of seminal follicles in males and ovarioles in females are stable within but fairly variable among the species, the modal value of the follicle number is 10 per testis. Contrary to what might be expected from other fulgoroid families, such as the Dictyopharidae and Delphacidae, the variability in these characters revealed neither regular trends nor evident correspondence with the taxonomy of Issidae. In the Caliscelidae, all species studied had testes consisting of 6 follicles each and karyotypes of 2n = 24 + X and 26 + XY, respectively, in 3 and 1 species. The only representative studied of the Acanaloniidae, Acanalonia bivittata (Say, 1825), had 2n = 24 + X and 13 follicles in its testis. The variability in all the characters investigated is discussed and compared to other fulgoroid families, primarily to the most extensively studied families, Delphacidae and Dictyopharidae.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
25557. Variability of Mammary Carcinogenesis Induction in Female Sprague-Dawley and Wistar:Han Rats: the Effect of Season and Age
- Creator:
- Kubatka, P., Eva Ahlersová, Ivan Ahlers, Bianka Bojková, Kalická, K., Eva Adámeková, Marková, M., Chamilová, M., and Čermáková, M.
- Format:
- print, bez média, and svazek
- Type:
- article, studie, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, Mammary carcinogenesis, Seasons, Critical periods, Rat strains, Susceptibility, 14, and 612
- Language:
- English
- Description:
- It is important to determine and clarify the variability of mammary carcinogenesis induction in animal experimental studies particularly in connection with chemoprevention projects. The circannual seasonal rhythms of hormone levels or various parameters within the immune system may involve factors participating in mammary gland carcinogenesis. In our study, 19 experiments were conducted and all of them lasted for about 25 weeks after chemical carcinogen administration (DMBA or NMU) under standard laboratory conditions. Females of two rat strains - a medium susceptible Sprague-Dawley strain and a very low susceptible Wistar:Han were used. We observed not only the effect of seasonal changes but also the effect of age after single or repeated carcinogen administration. The seasonal dependence of mammary carcinogenesis with higher tumor incidence during long days in comparison with winter short days has been demonstrated in Sprague-Dawley rats. In experiments on the Wistar:Han strain, certain features of seasonal character were recorded, although the very low susceptibility of this strain to mammary carcinogenesis might have influenced the results. A limited period of carcinogen administration in early puberty around postnatal days 43-46 (higher susceptibility), when compared to the period after postnatal day 50, is the factor significantly increasing incidence and frequency of mammary carcinogenesis in the Sprague-Dawley strain. Our results indicate the need to consider the effect of season and age of animals at the time of carcinogen administration on rat mammary carcinogenesis induction. However, the application of the results obtained in one strain of experimental animals may only lead to misleading conclusions., P. Kubatka, E. Ahlersová, I. Ahlers, B. Bojková, K. Kalická, E. Adámeková, M. Marková, M. Chamilová, M. Čermáková., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
25558. Variability of mitochondrial respiration in relation to sepsis-induced multiple organ dysfunction
- Creator:
- Kohoutová, M., Dejmek, J., Tůma, Z., and Kuncová, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- sepsis, mitochondria, oxygen consumption, multiple organ dysfunction, and animal models
- Language:
- English
- Description:
- Ample experimental evidence suggests that sepsis could interfere with any mitochondrial function; however, the true role of mitochondrial dysfunction in the pathogenesis of sepsis-induced multiple organ dysfunction is still a matter of controversy. This review is primarily focused on mitochondrial oxygen consumption in various animal models of sepsis in relation to human disease and potential sources of variability in experimental results documenting decrease, increase or no change in mitochondrial respiration in various organs and species. To date, at least three possible explanations of sepsis-associated dysfunction of the mitochondrial respiratory system and consequently impaired energy production have been suggested: 1. Mitochondrial dysfunction is secondary to tissue hypoxia. 2. Mitochondria are challenged by various toxins or mediators of inflammation that impair oxygen utilization (cytopathic hypoxia). 3. Compromised mitochondrial respiration could be an active measure of survival strategy resembling stunning or hibernation. To reveal the true role of mitochondria in sepsis, sources of variability of experimental results based on animal species, models of sepsis, organs studied, or analytical approaches should be identified and minimized by the use of appropriate experimental models resembling human sepsis, wider use of larger animal species in preclinical studies, more detailed mapping of interspecies differences and organ-specific features of oxygen utilization in addition to use of complex and standardized protocols evaluating mitochondrial respiration.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
25559. Variability of peripheral pulse wave velocity in patients with diabetes mellitus type 2 during orthostatic challenge
- Creator:
- Svačinová, Jana, Hrušková, Jana, Jakubík, Juraj, Budinskaya, Ksenia, Hidegová, Simona, Fabšík, Martin, Sieglová, Helena, Kaščáková, Zuzana, Novák, Jan, and Nováková, Zuzana
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- pulse wave velocity, variability, diabetes mellitus, arterial stiffness, and orthostasis
- Language:
- English
- Description:
- Diabetes mellitus 2 (DM2) is the seventh cause of death worldwide. One of the reasons is late diagnosis of vascular damage. Pulse wave velocity (PWV) has become an independent marker of arterial stiffness and cardiovascular risk. Moreover, the previous studies have shown the importance of beat-to-beat PWV measurement due to its variability among the heart cycle. However, variability of PWV (PWVv) of the whole body hasn't been examined yet. We have studied a group of DM II and heathy volunteers, to investigate the beat-to-beat mean PWV (PWVm) and PWVv in the different body positions. PWV of left lower and upper extremities were measured in DM2 (7 m/8 f, age 68±10 years, BP 158/90±19/9 mm Hg) and healthy controls (5 m/6 f, age 23±2 years, BP 117/76±9/5 mm Hg). Volunteers were lying in the resting position and of head-up-tilt in 45° (HUT) for 6 min. PWVv was evaluated as a mean power spectrum in the frequency bands LF and HF (0.04-0.15 Hz, 0.15-0.5 Hz). Resting PWVm of upper extremity was higher in DM2. HUT increased lower extremity PWVm only in DM2. Extremities PWVm ratio was significantly lower in DM2 during HUT compared to controls. LF and HF PWVv had the same response to HUT. Resting PWVv was higher in DM2. Lower extremity PWVv increased during HUT in both groups. PWVm and PWVv in DM2 differed between extremities and were significantly influenced by postural changes due to hydrostatic pressure. Increased resting PWVm and PWVv in DM2 is a marker of increased arterial stiffness.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
25560. Variability of species of Babesia Starcovici, 1893 in three sympatric ticks (Ixodes ricinus, Dermacentor reticulatus and Haemaphysalis concinna) at the edge of Pannonia in the Czech Republic and Slovakia
- Creator:
- Rybářová, Markéta, Honsová, Michaela, Ivo Papoušek, and Pavel Široký
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitologie, parasitology, host-specificity, piroplasms, species diagnosis, 18S rRNA, 2, and 59
- Language:
- English
- Description:
- The distribution, variability and host specificity of species of Babesia Starcovici, 1893 were studied in questing ticks collected on the northwestern edge of the Pannonian Basin in the south-easternmost part of the Czech Republic and in western Slovakia. The area is characterised by relatively natural floodplain habitats and the sympatric occurrence of three tick species possessing wide host spectra, namely Ixodes ricinus (Linnaeus), Dermacentor reticulatus (Fabricius) and Haemaphysalis concinna Koch. Analysis was carried out on 1,408 I. ricinus, 2,999 D. reticulatus and 150 H. concinna altogether, collected from 59 localities. We documented the presence of Babesia spp. not only in I. ricinus but also in H. concinna in the Czech Republic. Two isolates from I. ricinus were classified as B. venatorum Herwaldt, Cacciò, Gherlinzoni, Aspöck, Slemenda, Piccaluga, Martinelli, Edelhofer, Hollenstein, Poletti, Pampiglione, Löschenberger, Tura et Pieniazek, 2003 (formerly determined as Babesia sp. EU1), which is a zoonotic parasite and can cause human babesiosis. The rest of our amplicons were very similar to B. canis (Piana et Galli-Valerio, 1895), which is usually transmitted by D. reticulatus. Despite the huge amount of examined samples, all D. reticulatus ticks were Babesia-free. Due to this finding, we did not consider our obtained isolates to be B. canis, but other closely related species possessing a similar sequence of the studied portion of 18S rDNA. Although this genetic marker is most frequently used in PCR-based diagnostic methods of babesias, its low variability compromises its reliability in studies based only on this marker., Markéta Rybářová, Michaela Honsová, Ivo Papoušek, Pavel Široký., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public