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      • KCI등재

        Hierarchical clustering analysis for the distribution of origanum-oil components in dense CO₂

        Ugur Akman,Nesrin Okay,Oner Hortaçsu 한국화학공학회 2008 Korean Journal of Chemical Engineering Vol.25 No.2

        Hierarchical Clustering (HC) technique is demonstratively applied to analyze the distribution and classification of essential-oil components in oil and dense (subcritical/supercritical) CO₂phases. For this purpose, relative-equilibrium- distribution data obtained for the 24 characteristic components of origanum-oil (Origanum Munituflorum) at 35, 45, 55 oC and 20-110 atm pressure range are used. With 24 components and 25 different pressure levels at three different temperatures, the total number of data points amounts to 600, which is large compared to other similar works, making the task of drawing of conclusions by visual inspection quite tedious. As demonstrated in this work, the use of HC technique facilitates the classification of the distribution of essential-oil components. HC-based classification analysis helps to reveal that the distributions of monoterpenes are the most sensitive to changes in temperature and pressure, and they are more soluble in CO₂ especially in the supercritical region. At 35 oC, at higher pressures, due to high solvent density/power, almost all components show similar distributions in the CO₂ and oil phases, indicating the loss of fractionation potential. Deterpenation by CO₂ is more favorable at higher temperatures. Cophnetic correlation shows the significance level of data clustering. HC analysis proved to be a useful tool in classification of the components and in determination of component clusters in the dense-gas and liquid phases.

      • Effects of Hypobaric Conditions on Apoptosis Signalling Pathways in HeLa Cells

        Arican, Gul Ozcan,Khalilia, Walid,Serbes, Ugur,Akman, Gizem,Cetin, Idil,Arican, Ercan Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.12

        Nowadays increasing effectiveness in cancer therapy and investigation of formation of new strategies that enhance antiproliferative activity against target organs has become a subject of interest. Although the molecular mechanisms of apoptosis can not be fully explained, it is known that cell suicide program existing in their memory genetically is activated by pathophysiological conditions and events such as oxidative stress. Low pressure (hypobaric) conditions that create hypoxia promote apoptosis by inhibiting cell cycling. In this study, determination of the effects of fractional hypobaric applications at different times on HeLa cells at cellular and molecular levels were targeted. Experiments were carried out under hypobaric conditions (35.2 kPa) in a specially designed hypobaric cabin including 2% $O_2$ and 98% N. Application of fractional hypobaric conditions was repeated two times for 3 hours with an interval of 24 hours. At the end of the implementation period cells were allowed to incubate for 24 hours for activation of repair mechanisms. Cell kinetic parameters such as growth rate (MTT) and apoptotic index were used in determination of the effect of hypobaric conditions on HeLa cells. Also in our study expression levels of the Bcl-2 gene family that have regulatory roles in apoptosis were determined by the RT-PCR technique to evaluate molecular mechanisms. The results showed that antiproliferative effect of hypobaric conditions on HeLa cells started three hours from the time of application and increased depending on the period of exposure. While there was a significant decrease in growth rate values, there was a significant increase in apoptotic index values (p<0.01). Also molecular studies showed that hypobaric conditions caused a significant increase in expression level of proapoptotic gene Bax and significant decrease in antiapoptotic Bfl-1. Consequently fractional application of hypobaric conditions on HeLa cell cultures increased both antiproliferative and apoptotic effects and these effects were triggered by the Bax gene.

      • Intra-Peritoneal Cisplatin Combined with Intravenous Paclitaxel in Optimally Debulked Stage 3 Ovarian Cancer Patients: An Izmir Oncology Group Study

        Unal, Olcun Umit,Yilmaz, Ahmet Ugur,Yavuzsen, Tugba,Akman, Tulay,Ellidokuz, Hulya Asian Pacific Journal of Cancer Prevention 2014 Asian Pacific journal of cancer prevention Vol.15 No.15

        Background: The advantage of intra-peritoneal (IP) chemotherapy (CT) in the initial management of ovarian cancer after cytoreductive surgery is well known. The feasibility and toxicity of a treatment regimen with an IP + intravenous CT (IPIVCT) for optimally debulked stage III ovarian cancer were here evaluated retrospectively. Materials and Methods: A total of 30 patients were treated in our institution between October 2006 and February 2011. Patients received IV paclitaxel $175mg/m^2$ over 3 hours followed by IP cisplatin $75mg/m^2$ on day 1; they also received IP paclitaxel $60mg/m^2$ on day 8. They were also scheduled to receive 6 courses of CT every 21 days. Results: The median age of the patients was 55 years (35-77), and the majority had papillary serous ovarian cancer (63.3%). The patients completed a total of 146 cycles of IPIVCT. Twenty-eight were able to receive at least three cycles of IPIVCT and 18 (60%) completed the scheduled 6 cycles. Two patients discontinued the IPIVCT because of toxicity of chemotherapy agents and 6 had to stop treatment due to intolerable abdominal pain during IP drug administration, obstruction and impaired access. Grade 3/4 toxicities included neutropenia (6 patients; 20%), anemia (2 patients; 6.7%) and nausea-vomiting (2 patients; 6.7%). Doses were delayed in 12 cycles (8%) for neutropenia (n=6), thrombocytopenia (n=3) and elevated creatinine (n=3). Drug doses were not reduced. The median duration of progression-free survival (PFS) was 47.7 months (95%CI, 38.98-56.44) and overall survival (OS) was 51.7 months (95%CI, 44.13-59.29). Two and five-year overall survival rates were 75.6 % and 64.8%, respectively. Conclusions: IPIVCT is feasible and well-tolerated in this setting. Its clinically proven advantages should be taken into consideration and more efforts should be made to administer IPIVCT to suitable patients.

      • Relationship between Epidermal Growth Factor Receptor Gene Mutations and Clinicopathological Features in Patients with Non-Small Cell Lung Cancer in Western Turkey

        Unal, Olcun Umit,Oztop, Ilhan,Calibasi, Gizem,Baskin, Yasemin,Koca, Dogan,Demir, Necla,Akman, Tulay,Ellidokuz, Hulya,Yilmaz, Ahmet Ugur Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.6

        Background: To investigate epidermal growth factor receptor (EGFR) gene mutations in patients with non-small cell lung cancer (NSCLC) and to analyze any relationship with clinicopathological features and prognosis. Materials and Methods: EGFR gene exons 18-21 in 48 specimens of paraffin-embedded tumor tissue from NSCLC patients were amplified by PCR, followed by direct sequencing and analysis of links to clinicopathological features and prognosis. Results: EGFR mutations were detected in 18 of 48 (42.6%) patients with NSCLC. There were 9 cases of mutations in exon 20, 7 in exon 19 and 2 in exon 21. Mutations were more frequently observed in women (5/7 pts, 71.4%) than in men (13/41 pts, 31.7%) (p=0.086) and in non-smokers (5/5 pts, 100%) than smokers (13/43 pts, 30.2%). There was negative correlation of EGFR mutations with smoking status (p=0.005). EGFR mutations were more frequently observed with adenocarcinoma histology (13/32 pts, 40.6%) than in other types (5/16 pts, 31.3%) (p=0.527). The patients with EGFR mutations had better survival than those with wild-type EGFR (p=0.08). There was no association of EGFR mutations with metastatic spread. Conclusions: EGFR mutations in NSCLC were here demonstrated more frequently in females, non-smokers and adenocarcinoma histology in the western region of Turkey. Patients with EGFR mutations have a better prognosis.

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