Yazar "Oztas, H." seçeneğine göre listele
Listeleniyor 1 - 6 / 6
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Assessing eco-toxicological effects of industrial 2,4-D acid iso-octylester herbicide on rat pancreas and liver(INFORMA HEALTHCARE, 2013) Kalipci, E.; Ozdemir, C.; Oztas, H.We studied the eco-toxic and carcinogenic effects of a commonly used 2,4-D acid iso-octylester herbicide on rat liver and pancreas. The rats in Group 1 were fed a standard feed and the rats in Group 2 were fed with standard feed to which was added 200 mg/kg/day 2,4-D acid iso-octylester for 16 weeks. Azaserine, 30 mg/kg/body weight, was injected into rats of Groups 3 and 4 to investigate the effects of 2,4-D acid iso-octylester on the development of neoplasms. After feeding the rats with neoplasms in Group 4 with food including 200 mg/kg/day 2,4-D acid iso-octylester for 16 weeks, an autopsy was carried out on all animals. We found that 2,4-D acid iso-octylester caused the formation of atypical cell foci (ACF) in the pancreata and livers of rats. ACF that were formed experimentally by exposure to azaserine had increased diameter, volume and number of atypical cell foci/mm 2 and mm 3 after exposure to 2,4-D acid iso-octylester. Our observations indicated that this herbicide potentially is a cancer initiator.Öğe ATTITUDES, KNOWLEDGE, BEHAVIOUR OF FIRST-YEAR BIOLOGY AND PHYSICS EDUCATION STUDENTS PERTAINING TO THE ENVIRONMENT(SCIBULCOM LTD, 2013) Dalbudak, T.; Oztas, F.; Oztas, H.In this study, it was aimed to investigate whether there exist differences between the attitudes and behaviour of first-year biology education and physics education students towards the environment. It was investigated whether there were differences between the attitudes and behaviour of first-year biology education students, who had been enrolled in the program in 2011-2012, towards the environment and those of first-year physics education students, who were thought to have different (positive/negative) environmental attitudes and behaviour. Findings were analysed using statistical methods, which led to the conclusion that there are differences between the environmental attitudes and behaviour of the 2 groups (p < 0.05). It was determined that biology education students were more conscious than physics education students for environmental discussion issues. It is thus possible to argue that these differences had been the main factor behind their selection of different branches of science.Öğe In Secondary School Pupils Alternative Views About Inorganic Substances and Their Metabolic Effect in Cells(Sila Science, 2012) Gokmenoglu, R.; Oztas, F.; Kalipci, E.; Gokler, I.; Oztas, H.; Ozay, E.The aim of this study has been designated detection of misconceptions in secondary school biology text book (9th Grade) about inorganic substances available in cells and their cellular functions. It is well known that students' misconceptions about biological subject and their analysis's are vital important for biology education in secondary school biology education. Previous studies have been shown that pre-knowledge of pupils about vitality and related subjects make difficult their understanding and comment new biological subjects. Also it makes difficult understanding basic functions of inorganic substances that they play an important role in cells metabolism. For this, this study has been focused on detection of misconceptions on secondary school biology text book (9th Grade) subject about inorganic substances in cells and their cellular functions. The space of research has been restricted with Private Enderun Secondary School located in central part of Konya Province. Totally, forty students have been attended to research that a questionnaire included two step ten questions with closed and open ended has been applied. The results have been analyzed according to statistically. The findings have been shown that pupils have some misconceptions about basic properties of inorganic substances available in cells and their functions. It has been detected that some pupils accepted the inorganic substance as an energy sources for cells. Also they mostly did not realized catalyst roles in cell metabolism. Although the carbon dioxide has been accepted by pupils as an inorganic substance, they were short of explain reasons. Another dilemma of students were did not explain connections organic and inorganic substances in cell metabolism.Öğe In vitro antileishmanial activity of Adana propolis samples on Leishmania tropica: a preliminary study(SPRINGER, 2008) Duran, G.; Duran, N.; Culha, G.; Ozcan, B.; Oztas, H.; Ozer, B.Propolis (bee glue) is a natural resinous hive product, collected from various plant sources. It has attracted much attention as a useful substance applied in medicine due to its pharmacological activities. It was aimed to investigate the in vitro effects of an ethanolic extract of Adana propolis samples on the growth of Leishmania tropica. Parasite cells were treated with five concentrations (25, 50, 100, 50, 500, and 750 mu g/ml) of the propolis. The number of promastigotes in each concentration was calculated using a hemocytometer slide at 24, 48, and 72 h after being harvested. In the experiments, it was determined that the concentrations up to 100 mu g/ml of the propolis did not exhibit antileishmanial activity against the parasites cells. At these concentrations, there was no changes in terms of morphologically. In addition, there was no statistically significant difference in terms of cell count between control and these three groups (p > 0.05). However, in culture media containing the propolis samples at 250, 500, and 750-mu g/ml concentrations, statistically significant differences in cell counts were observed, as compared to the control group (p < 0.05). Our results demonstrate that ethanolic extracts of Adana propolis samples reduce the proliferation of L. tropica parasites significantly.Öğe Possible neoplastic effects of acrylamide on rat exocrine pancreas(TAYLOR & FRANCIS LTD, 2013) Yener, Y.; Kalipci, E.; Oztas, H.; Aydin, A. D.; Yildiz, H.We investigated whether the acrylamide formed during cooking carbohydrate-rich foods at high temperatures causes neoplastic changes in rat pancreas. Azaserine, which is an amino acid derivative that has the ability to initiate neoplastic changes in rat pancreas, was injected into 14-day-old male rats once a week for three weeks. Acrylamide was given to both azaserine-injected and non-injected rats at doses of 5 and 10 mg/kg/day in drinking water for 16 weeks after which tissue slides were prepared from the pancreata. Pancreas weights and body weights of rats treated with azaserine and acrylamide together increased significantly compared to the other groups. Moreover, the size, average diameter and volume of atypical acinar cell foci that developed in the pancreata of rats treated with azaserine and acrylamide together increased significantly compared to rats treated with either azaserine or acrylamide alone and control groups. Atypical acinar cell adenoma or adenocarcinoma was not observed in the pancreata of rats in any group.Öğe SCHOOL STUDENTS DILEMA ABOUT ENVIRONMENTAL RULES AND ATTITUDES. DO THEY REALY FEEL RESPONSIBILITY FOR THE ENVIRONMENT?(SCIBULCOM LTD, 2014) Oztas, F.; Tanriverdi, H.; Oztas, H.The aim of present study was to determine the 10th grade high school students attitudes and behaviours towards the environment. The research data were collected via a questionnaire from 242 students who are in 10th grade in high school. The findings of current study have shown that the students have some incorrect alternative views about global warming; mostly they have defect knowledge about global warming. Findings show that it is a necessity for environment education to be re-designed in a way which will include individuals and society consumption features. In order to reach a success in solving environmental problems, it is a must for students at all levels to be educated for the environment and environmental values. It is not only enough for students to know biologically-oriented environmental pollution and environmental values, but also it is necessary for students to know physical and chemical problems.
