41. The role of thyroid radiation carcinogenesis in ratsKatarina Koritnik, Andrej Cör, 1998, original scientific article Abstract: The aimof this study was to test the hypothesis on the protective role of thyroxin administration before and during irradiation on the occurrence of thyroid carcinoma in rats. Application of thyroxin before and during irradiation was expected to decrease production of thyrotropin by the hypophyseal feedback mechanism, caused by radiation damage of thyroid tissue. Stabilizing the thyroid cells in this way during irradiation would thus make them less radiosensitive. In the experiment, we first divided 81 three to fourweek old Wistar strain rats of both sexes into two groups, i.e. thyroxin (T4) and water (H2O). The T4 rats were injected 1% thyroxin solution (0.01 mg/100 g body weight) twice a day for 15 days, while the H2O rats received saline in the same way. After ten days, the two main groups were divided each into two subgroups. The rats from both irradiated subgroups (T4/X and (H2O/X) recieved 10 Gy to the neck area. They were iradiated with a telecobalt machinefor five consecutive days with one direct field. During a two years follow - up, all moribund animals were sacrificed and their thyroid glands taken. The rest of the thyroid glands were taken at the end of the experiment.All glands were pathohistologically analysed. Besides, all suspicious and enlarged extrathyroid organs and tissues were examined and the occurrence of tumors was noted. Pathohistological examination revealed the occurrence of 8 thyroid carcinomas and 7 adenomas in the H2O/X group, and 3 adenomas in the T4/X group. In the iradiated group of rats without thyroxin, significantly (P = 0.01) more thyroid carcinomas occurred than in the irradiated group without thyroxin.
Published in DiRROS: 19.01.2024; Views: 175; Downloads: 41
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43. p53 and lung cancer - more frequent p53 overexpression in patients with multiple primary tumoursTomaž Rott, Mario Poljak, Olga Staniša, Janez Orel, Andrej Debeljak, 1994, professional article Keywords: rak (medicina), pljuča, pljučni rak, biokemija, geni
Published in DiRROS: 11.01.2024; Views: 160; Downloads: 47
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46. Biorefining twin transition : digitalisation for bio-based chemicals/materials - discovery, design and optimisationMatej Žula, Miha Grilc, Andrii Kostyniuk, Giorgio Tofani, Edita Jasiukaityte, Tina Ročnik, Ramesh Kumar Chowdari, Žan Lavrič, Janvit Teržan, Brigita Hočevar, Ana Jakob, Emilija Rakić, Brett Pomeroy, Miša Mojca Cajnko, Filipa A. Vicente, Dana Marinič, Ana Oberlintner, Uroš Novak, Davide Benedetto Tiz, Matej Huš, Blaž Likozar, 2023, original scientific article Published in DiRROS: 10.01.2024; Views: 166; Downloads: 78
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47. O domorodnosti alpskega kozoroga v SlovenijiAndreja Nève Repe, Elena Bužan, Borut Toškan, Jernej Javornik, Boštjan Pokorny, Andrej Arih, Lars Zver, Maruša Prostor, Miha Krofel, Matija Stergar, Klemen Jerina, Hubert Potočnik, Rok Černe, Aleš Poljanec, 2023, professional article Abstract: Alpski kozorog (Capra ibex) je alpski endemit. Na območju Slovenije naj bi bila vrsta iztrebljena v drugi polovici 17. stoletja, globalno pa je bila zaradi prelova na robu izumrtja konec 19. stoletja. Preživela je le populacija na širšem območju parka Gran Paradiso na skrajnem zahodu Alp v Italiji. Zaradi naselitev in drugih varstvenih programov sedaj alpski kozorog živi v celotnih Alpah, vključno s Slovenijo. Vendar pri nas njegove populacije nazadujejo in so v zelo slabem stanju, kar je lahko rezultat več dejavnikov. Malo izvornih osebkov ob naselitvah, zgodovinska ozka grla in ločenost kolonij so povzročili parjenje v sorodstvu, kar je slabšalo genetsko stanje populacij in lahko negativno vpliva tudi na demografijo. K številčnemu zmanjševanju vrste so lahko prispevale tudi bolezni. Za dolgoročno ohranitev alpskega kozoroga v Sloveniji so nujni takojšnji aktivni ohranitveni ukrepi, pogoj pa je ustrezna opredelitev izvornosti vrste, saj je (bila) zaradi prejšnjih pomanjkljivih podatkov umeščena med tujerodne. V prispevku na podlagi arheo-zooloških, genetskih in preliminarnih habitatnih analiz utemeljujemo, da je v Sloveniji kozorog domorodna vrsta. V raziskavah smo pokazali, da je vrsta živela na ozemlju zdajšnje Slovenije v poznoantičnem in zgodnje srednjeveškem obdobju. Preliminarno smo določili tudi primernost in povezanost habitata kozoroga v slovenskem alpskem svetu ter nakazali verjetne potrebne ukrepe za ohranitev vrste v Sloveniji.
Keywords: Capra ibex, izvornost vrste, programi varstva, Alpe, habitat, genetika
Published in DiRROS: 09.01.2024; Views: 237; Downloads: 66
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48. Tehnične smernice za ohranjanje in rabo genskih virov : lipa in lipovec = Tilia platyphyllos, Tilia cordataIgor Dakskobler, Robert Brus, Andrej Verlič, Nikica Ogris, Gregor Božič, 2013, professional article Keywords: genski viri, drevesne vrste, tehnične smernice, lipa, Tilia platyphyllos, lipovec, Tilia cordata, Slovenija
Published in DiRROS: 20.12.2023; Views: 239; Downloads: 0 |
49. Tehnične smernice za ohranjanje in rabo genskih virov : navadna in puhasta breza = Betula pendula, Betula pubescensAndrej Držaj, Robert Brus, Hojka Kraigher, 2012, professional article Keywords: genski viri, drevesne vrste, tehnične smernice, navadna breza, puhasta breza, Betula pendula, Betula pubescens, Slovenija
Published in DiRROS: 20.12.2023; Views: 176; Downloads: 55
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50. Effect of the cooling regime on the mineralogy and reactivity of belite-sulfoaluminate clinkersSabina Dolenec, Katarina Šter, Maruša Mrak, Klara Žagar, Andrej Ipavec, Lea Žibret, 2020, original scientific article Abstract: This study investigated the influence of different cooling regimes on the microstructure and consequent reactivity of belite-sulfoaluminate clinkers. The cement clinkers were synthesized by incorporating secondary raw materials, such as titanogypsum and bottom ash, to the natural raw materials. Clinker phases were determined by Rietveld quantitative phase analysis, while the distribution morphology and the incorporation of substitute ions in the phases were characterized by scanning electron microscopy using energy-dispersive X-ray spectroscopy (SEM/EDS). Clinker reactivity was studied using isothermal calorimetry and was additionally investigated through compressive strength, which was determined for the cement prepared from the synthesized clinkers. X-ray diffraction analysis showed that, as well as the three main phases (belite, calcium sulfoaluminate, and ferrite), the clinkers contained additional minor phases (mayenite, gehlenite, arkanite, periclase, and perovskite), the ratios of which varied according to the cooling regime utilized. Microscopic observations indicated that the cooling regime also influenced the crystal size and morphology of the main phases, which consequently affected clinker reactivity. Furthermore, a smaller amount of substitute elements was incorporated in the main phases when cooling was slowed. Results showed that, in comparison to clinkers cooled at slower rates, air quenched clinkers reacted faster and exhibited a higher compressive strength at 7 days.
Keywords: clinkers, belite, calcium sulfoaluminate, cooling, microstructure, reactivity
Published in DiRROS: 20.12.2023; Views: 187; Downloads: 76
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