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10322. 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
10323. 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
10324. 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
10325. Variable expression of hypercholesterolemia in apolipoprotein E2* (Arg136 - Cys) Heterozygotes
- Creator:
- Jaroslav Hubáček, Jan Piťha, Petr Stávek, Schmitz, G., and Rudolf Poledne
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, sekvenování DNA, metabolismus lipidů, DNA sequencing, lipid metabolism, apolipoprotein E, rare mutation, PCR, 14, and 612
- Language:
- English
- Description:
- In the process of population screening for apo E gene polymorphism with the PCR and subsequent restriction analysis, we identified a female who demonstrated heterozygosity for an unusual restriction fragment caused by the loss of a CfoI restriction site. Sequence analysis of the apo E gene was performed and a carrier of the mutant allele with C - T substitution at cDNA position 3817 was identified, which caused an Arg136 - Cys change. The first-line relatives have been screened for this rare mutation with PCR and restriction analysis of PCR products. The complete lipoprotein parameters have been determined in the probands family. In the family, only one child had the same mutant allele as his mother had. The proband (7.49 mmol/l) with her siblings had hypercholesterolemia and a high body mass index (BMI 31.6 kg/m2). By contrast, her son had a normal lipid spectrum with normal BMI. We described the mutation apo E2* (Arg136 - Cys) in a family with elevated lipid levels, but there was no confirmation of the connection between this mutation and type III hyperlipoproteinemia or hyperlipoproteinemia at all. In the case of this mutation, other factors (mainly genetic) are important for the development of lipid metabolism disorders., J. A. Hubáček, J. Piťha, P. Stávek, G. Schmitz, R. Poledne., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10326. Variační počet, přirozený aparát fyziky
- Creator:
- Musilová, Jana and Musilová, Pavla
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- variační počet, variační metody, physics, calculus of variations, variational methods, matematická estetika, variační matematika, variační fyzika, 6, and 53
- Language:
- Czech and English
- Description:
- Říká se, že jedním ze znaků správné fyzikální teorie je její krása. Máme-li na mysli estetičnost matematickou, patří variační počet k matematickým metodám, které naplňují tento požadavek vrchovatě. Je také pravda, že správné (zkušeností a experimentem prověřené) fyzikální teorie bývají variační, tj. odvoditelné z variačního principu: Klasická mechanika, relativistická mechanika, kvantová mechanika, klasická elektrodynamika... Na zcela elementární úrovni předkládáme základní myšlenku a klasické postupy variačního počtu, s ukázkami použití v geometrii a fyzice. Zaměříme se pouze na variační princip prvního řádu, s důrazem na mechaniku, kde na rozdíl od teorie pole závisí řešené úlohy pouze na jedné nezávisle proměnné, ve fyzice obvykle na čase., It is said that one of the characteristic features of physical theories is their beauty. Having in mind the "mathematical aesthetic appearance" one can say that the calculus of variations highly fulfils this requirement! It is also well known that correct physical theories (those verified experimentally), are often variational, i.e. based on a variational principle: classical mechanics, relativistic mechanics, quantum mechanics, classical electrodynamics, etc. We present, at a very basic level, the fundamental ideas and classical approaches of the calculus of variations, including examples of their use in geometry and physics. We focus on the first order variational principle, emphasizing mechanics, because contrary to field theories, the variational problems in mechanics depend on one independent variable only (usually time in physics)., Jana Musilová, Pavla Musilová., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10327. Variation in CDKAL1 gene is associated with therapeutic response to sulphonylureas
- Creator:
- Zbynek Schroner, Martin Javorský, Halušková, J., Klimčáková, L., Babjaková, E., Fabianová, M., Slabá, E., Kozárová, M., and Ivan Tkáč
- Type:
- article, články, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, fyziologie člověka, human physiology, pharmacogenetics, sulphonylureas, CDKAL1, glycemic control, type 2 diabetes, 14, and 612
- Language:
- English
- Description:
- The aim of the present pilot pharmacogenetic study was to analyse quantitative effects of sulphonylurea treatment in addition to metformin on parameters of glycemic control with respect to CDKAL1 genotypes in patients with type 2 diabetes. Effect of 6-month sulphonylurea therapy on glycemic control according to CDKAL1 genotypes was evaluated in 101 patients with type 2 diabetes who failed to achieve glycemic control on metformin monotherapy. CDKAL1 rs7756992 polymorphism was determined by melting curve analysis of small amplicon following real-time PCR. After sulphonylurea treatment fasting plasma glucose (FPG) levels were significantly different (p=0.045) among three CDKAL1 genotype groups (AA: n=49; AG: n=36; GG: n=16). In a dominant genetic model, carriers of the G-allele (AG+GG, n=52) achieved significantly lower FPG levels in comparison with patients with the AA genotype (6.90±1.08 vs. 7.48±1.12 mmol/l, p=0.013). Consequently, adjusted ΔFPG was significantly higher in the AG+GG compared to the AA group (1.48±1.51 vs. 1.02±1.33 mmol/l, p=0.022). Similar trend was observed for HbA1c levels, but the difference between the genotype groups did not reach the level of statistical significance. Relatively small number of included patients is a limitation of the present study. In conclusion, our results suggest that the magnitude of FPG reduction after 6-month sulphonylurea treatment in patients with type 2 diabetes is related to the variation in CDKAL1., Z. Schroner ... [et al.]., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10328. Variation in parameters affecting risk of human disease due to TBE virus
- Creator:
- Korenberg, E. I. and Kovalevskii, Yu V.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- tick-borne encephalitis, Ixodes persulcatus, and risk of infection
- Language:
- English
- Description:
- To rank variables affecting risk of human disease due to tick-borne encephalitis (TBE) virus in the Russian Far East, we compared annual changes in ( 1 ) frequency of human contact with vector ticks, (2) prevalence of infection in the tick population and (3) quantity of virus present infected ticks. Sites were sampled uniformly over a 4-year period in a forested region where Ixodes persulcatus serves as the principle vector. The questing density of ticks on vegetation remained relatively constant during the course of this study. The frequency of contacts of the local human population with ticks carrying different doses of the TBE virus was changeable. The rate of TBE infection of humans in the study site corresponded to that of human contacts with highly infected ticks. The density of highly infected ticks represents the principal parameter for determining potential epidemiological significance of a natural TBE focus.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10329. Variation in teeth number, teeth and skull disorders in Eurasian lynx, Lynx lynx from Croatia
- Creator:
- Gomerčić, Tomislav, Gužvica, Goran, Đuras Gomerčić, Martina, Frković, Aloizije, Pavlović, Dubravka, Kusak, Josip, Sindičić, Magda, and Huber, Đuro
- Type:
- article and TEXT
- Subject:
- skull, congenitally absent teeth, supernumerary teeth, and reintroduced lynx
- Language:
- English
- Description:
- The last specimens of indigenous Eurasian lynx (Lynx lynx) in Croatia were exterminated around year 1903. Lynx dispersed back to Croatia after six animals were reintroduced to Slovenia from Slovakia in 1973. Considering the consequences of founder effect, genetic drift and expected high level of homozygosity, the goal of this paper was to determine variation in teeth number, teeth and skull disorders in Croatian lynx. It should also determine whether there has been a change in frequency of occurrence of developmental anomalies in relation to the population it originates from and in relation to other lynx populations. We studied 58 lynx skulls originating from the reintroduced lynx population. Changes on teeth and skull were found on 23 skulls (39.7%): supernumerary maxillary second premolar P2 (9 skulls, 15.5%), supernumerary mandibular second molar M2 (3 skulls, 5.2%), congenitally absent maxillary incisor (3 skulls, 6.9%), extra tooth between maxillary third incisor I3 and canine (1 skull, 1.7%) and acquired disorders of teeth and skull (9, 15.5%).
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
10330. Variation of some biochemical parameters in female yellowfin seabream, Acanthopagrus latus (Houttuyn) during reproductive cycle
- Creator:
- Hatami Nasari, Fatemeh, Kochanian, Preeta, Salati, Amir Parviz, and Pasha-Zanoosi, Hossein
- Type:
- article, model:article, and TEXT
- Subject:
- fish, electrolyte, enzyme, metabolite, Persian Gulf, plasma, and reproduction
- Language:
- English
- Description:
- In the present study changes of some blood parameters of wild female yellowfin seabream (Acanthopagrus latus) caught from Persian Gulf were assayed during reproductive cycle. Altogether, 120 female A. latus (15 each month) were captured monthly from October 2010 to May 2011 from the Mussa Creek in the north-west of Persian Gulf. Blood samples were collected from caudal vein; plasma was separated and kept at –80 °C till analysis. Total protein, glucose, cholesterol, triglyceride, electrolytes, calcium, sodium, chloride, magnesium, potassium plus hepatic enzymes, Alanine Amino Transferase (ALT) and Aspartate Amino Transferase (AST), were assayed in plasma sample. Total protein and calcium increased parallel to ovarian development and decreased after spawning time. Cholesterol and triglyceride had a peak during vitellogenesis and decreased after spawning but glucose had a peak during spawning time. Most of the electrolytes (sodium, magnesium and potassium) did not show any significant changes during the reproductive cycle in A. Latus. AST reached a peak during final maturation of ovaries but ALT did not show any significant difference during differentsampling times.Our findings showed that biochemical parameters could be used as indicators of physiological status during differentmaturation stage in this species.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public