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Damir Valić Irena Vardić Smrzlić Damir Kapetanović Zlatica Teskeredžić Bruna Pleše Emin Teskeredžić 《Biologia》2013,68(3):539-545
In order to determine an unknown fish population from the Vrana Lake, mitochondrial cytochrome b gene and non-coding nuclear region Cyfun P were investigated. Stabile population of Bulldog rudd, Scardinius dergle Heckel & Kner, the endemic Croatian freshwater fish in the Krka River, was genetically characterized with the same markers in order to compare it with the material from the Vrana Lake. Genetic markers were sequenced and aligned with the similar ones obtained from the GenBank in order to determine taxonomic and phylogenetic position of these two species. A significant discrepancy between nuclear genetic markers of our specimens and the sequence from the GenBank was found. Phylogenetic analysis suggested that the specimens from the Vrana Lake belong to the species S. hesperidicus. Morphometric characteristics, the maximum length and body mass showed new maximum values for both S. dergle and S. hesperidicus. 相似文献
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Importance of an appropriate visual presentation for avoiding a misconception of the menstrual cycle
Family planning, the prevention of unwanted pregnancy, and women’s reproductive health are topics that have received close attention for decades. It would therefore be fair to assume that there exists a good knowledge of the menstrual cycle. However, it is clear that many people have various misconceptions about the menstrual cycle and fertile days or ovulation, and that this process is still largely taught with the aid of materials and images that have not changed for many years. We investigated the effect of moving away from the usual teaching practice of using a 28-day diagram showing ovulation on the 14th day. A total of 184 students from three different high schools, aged between 17 and 18, participated in this research. The students who were taught using three diagrams showing different durations of the menstrual cycle showed a significantly better adoption of the facts and concepts compared to the students who were taught using a diagram of the average 28-day cycle. Our results confirmed that it is highly important to use appropriate visual displays in the teaching of the menstrual cycle and that it is essential to enhance the visual literacy of students and teachers. 相似文献
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The study aimed to establish the frequency of injuries in primary and secondary schools during leisure time and physical education classes in school as well as in group and individual sports. The sample included 2842 pupils from nine primary schools and 1235 students from five secondary schools in Slovenia. The data were processed with the SPSS statistical software package and the frequencies and Crosstabs were calculated. The results showed that substantially more pupils and students were injured in their leisure time than during physical education classes. Girls were more frequently injured in group and individual sports practiced during physical education classes and in individual sports practiced in their leisure time, whereas boys suffered more injuries in group sports practiced in their leisure time. As regards group sports, pupils and students were most frequently injured while playing football in their leisure time whereas, during physical education classes, they suffered most injuries in volleyball, followed closely by basketball and football; as regards individual sports, pupils and students were most frequently injured while cycling and rollerblading in their leisure time, whereas during physical education classes they suffered most injuries in athletics. 相似文献
6.
During implementation of the total skin electron treatment, using six-dual-field technique, at radiotherapy department a large number of measurements are needed. To assess depth dose curve required by clinicians and dose uniformity over a whole treatment plane, combinations of different irradiation parameters are used (electron energy, beam angle, scatterers). Measurements for each combination must be performed. One possible way to reduce number of measurements is to model the treatment using the Monte Carlo simulation of electron transport. We made a simplified multiple-source Monte Carlo model of electron beam and tested it by comparing calculations and experimental results. Calculated data differs less than 5 percent from measurements in the treatment plane. During the treatment patient can be approximated using cylinders with different diameters and orientations. We tried to model the depth dose variations in the total skin electron treatment not just around the body cross-section (simplified to cylinders of different diameters), but also along the body to account for the variations in body curvature longitudinally. This effect comes down to the problem of modeling distribution in different cylinders, but varying the longitudinal orientation of those cylinders. We compared Monte Carlo calculations and film measurements of depth dose curves for two orientations of the cylindrical phantom, which were the simplest for experimental arrangement. Comparison of the results proved accuracy of the model and we used it to calculate depth dose curves for a number of other cylinder orientations. 相似文献
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The RuvABC resolvase is indispensable for recombinational repair in sbcB15 mutants of Escherichia coli 下载免费PDF全文
Zahradka D Zahradka K Petranović M Dermić D Brcić-Kostić K 《Journal of bacteriology》2002,184(15):4141-4147
The RuvABC proteins of Escherichia coli play an important role in the processing of Holliday junctions during homologous recombination and recombinational repair. Mutations in the ruv genes have a moderate effect on recombination and repair in wild-type strains but confer pronounced recombination deficiency and extreme sensitivity to DNA-damaging agents in a recBC sbcBC background. Genetic analysis presented in this work revealed that the (Delta)ruvABC mutation causes an identical DNA repair defect in UV-irradiated recBC sbcBC, sbcBC, and sbcB strains, indicating that the sbcB mutation alone is responsible for the extreme UV sensitivity of recBC sbcBC ruv derivatives. In experiments with gamma irradiation and in conjugational crosses, however, sbcBC (Delta)ruvABC and sbcB (Delta)ruvABC mutants displayed higher recombination proficiency than the recBC sbcBC (Delta)ruvABC strain. The frequency of conjugational recombination observed with the sbcB (Delta)ruvABC strain was quite similar to that of the (Delta)ruvABC single mutant, indicating that the sbcB mutation does not increase the requirement for RuvABC in a recombinational process starting from preexisting DNA ends. The differences between the results obtained in three experimental systems used suggest that in UV-irradiated cells, the RuvABC complex might act in an early stage of recombinational repair. The results of this work are discussed in the context of recent recombination models which propose the participation of RuvABC proteins in the processing of Holliday junctions made from stalled replication forks. We suggest that the mutant SbcB protein stabilizes these junctions and makes their processing highly dependent on RuvABC resolvase. 相似文献
8.
Monosomics of cotton (Gossypium hirsutum L.) were obtained by irradiation of pollen by -rays and by irradiation of seeds by thermal neutrons. Many monosomics were derived directly from irradiation, but a number of monosomics were also recovered in the progeny of plants with translocations and of desynaptic plants. Only 28 primary monosomics showed normal pairing at metaphase-1 of meiosis. The others formec rare trivalents or additional univalents. Partial desynapsis was detected in some monosomics. The pollen fertility levels of monosomics are presented. New morphological characters were detected among the monosome plants of cotton. 相似文献
9.
Krsinic Frano; Caric Marina; Vilicic Damir; Ciglenecki Irena 《Journal of plankton research》2000,22(8):1441-1464
Lake Rogoznica, near ibenik, Croatia, is a salt coastal lakewith a maximum depth of about 15 m. During most of the year,this small, naturally eutrophied lake is highly stratified,with hypoxia/anoxia occurring in the bottom layer. Total anoxia,with the presence of hydrogen sulphide, was recorded on September27, 1997. At that moment, massive mortality of all planktonicand benthic organisms was observed. After the anoxia, Acartiaitalica, the only planktonic copepod species of the lake, re-establishedquickly. Before anoxia, the population dynamics of the A.italicapopulation depended primarily on predator/prey relationships.However, in the post-anoxic period, nutrientphytoplanktoncopepodrelationships became more important, as there was no longerany predation pressure. From all accounts, it would appear thatonly A.italica is adapted to the extreme conditions which appearfrom time to time in the lake, and that this species has animportant role in the functioning of the lake ecosystem. Acartiaitalica was very important for the gradual normalization oflife in the lake after total anoxia. 相似文献
10.
Novak-Stroligo M Alpeza-Dunato Z Kovacević D Caljkusić-Mance T 《Collegium antropologicum》2010,34(Z2):209-210
The endothelial cells are one of the most important structures in a donor cornea. Morphology and concentration of endothelial cells must be carefully evaluated with a specular microscope before transplantation. The aim of this study is to evaluate the status of corneal endothelium in glaucoma patients. Prospective study included 50 patients suffering from glaucoma and 50 patients in control group. Patients had no corneal disease, ocular inflammation, previous trauma or ocular surgery. Patients were not contact lens wearers. They were also analyzed in groups according to type of glaucoma. Specular microscopy was performed on central corneas. This study showed that patients with glaucoma have lower central corneal endothelial cell density than those without glaucoma of the same age group. Also, patients with pseudoexfoliative glaucoma had lower values of central endothelial cell density comparing to patients with open angle or angle closure glaucoma. 相似文献