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In this study, the relationships among problematic mobile phone use, age, gender, personality and chronotype of Turkish university students were examined. The study included 902 university students (73% female, 27% male) and their participation in the study was anonymous and voluntary. Data were collected from each participant by assessing a demographic questionnaire, Composite Scale of Morningness (CSM) as a measure of chronotype, the Big Five Inventory (BIG-5) for personality assessment and Mobile Phone Problem Usage Scale (MPPUS). The most important result was that CSM scores were the best predictor for problematic mobile phone usage, and as a consequence, evening-oriented university students scored higher on the MPPUS. This result remained, even when compared with the most influential personality predictor, conscientiousness. In addition, while extraversion positively predicted, emotional stable and chronotype negatively predicted problematic mobile phone use. Lastly, age and gender were not predictors of problematic mobile phone use. 相似文献
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Steven P. Govek Celine Bonnefous Jackaline D. Julien Johnny Y. Nagasawa Mehmet Kahraman Andiliy G. Lai Karensa L. Douglas Anna M. Aparicio Beatrice D. Darimont Katherine L. Grillot James D. Joseph Joshua A. Kaufman Kyoung-Jin Lee Nhin Lu Michael J. Moon Rene Y. Prudente John Sensintaffar Peter J. Rix Nicholas D. Smith 《Bioorganic & medicinal chemistry letters》2019,29(3):367-372
Potent estrogen receptor ligands typically contain a phenolic hydrogen-bond donor. The indazole of the selective estrogen receptor degrader (SERD) ARN-810 is believed to mimic this. Disclosed herein is the discovery of ARN-810 analogs which lack this hydrogen-bond donor. These SERDs induced tumor regression in a tamoxifen-resistant breast cancer xenograft, demonstrating that the indazole NH is not necessary for robust ER-modulation and anti-tumor activity. 相似文献
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Hacer Esen Saadet Alpdağtaş Mehmet Mervan Çakar 《Preparative biochemistry & biotechnology》2019,49(5):529-534
AbstractSeveral protein expression systems can be used to get enzymes in required quantities and study their functions. Incorporating a polyhistidine tag is a beneficial way of getting various enzymes such as FDHs for industrial applications. The NAD+ dependent formate dehydrogenase from Chaetomium thermophilum (CtFDH) can be utilized for interconversion of formate to carbon dioxide coupled with the conversion of NAD+ to NADH. In this study, N-terminal His tagged CtFDH (N-CtFDH) and C-terminal His tagged CtFDH (C-CtFDH) was constructed to learn the effect of His tag location on the activity and kinetic parameters of the enzyme. The solubility of proteins was not affected by tag position, however, an interference on the N-terminal region caused a deterioration in specific activity and the kinetic ability of enzyme. The obtained results indicated that the C-terminus of the enzyme is an appropriate region for tag engineering. The C-CtFDH has an approximately three-fold larger specific activity and two-fold higher catalytic efficiency than N-CtFDH. The results suggest that insertion of a His-tag at the N-terminal or C-terminal end of CtFDH has different effects on the protein and the N-terminal fragment of the protein is crucial for the function of CtFDH. 相似文献
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Thermal performance of quartz capillaries for vitrification 总被引:1,自引:1,他引:0
In this paper we report the thermal behavior of a new approach for vitrification. Thermal performance of traditional open pulled straws is compared with a new technique based on the combined use of quartz capillaries with slush nitrogen. This new method of vitrification achieved ultrafast cooling rates of 250,000 °C/min. As a result, a much lower concentration of cryoprotectant was needed to reach vitrification. In fact, a cryoprotectant solution typically used in oocyte slow freezing protocols was shown to remain transparent after cooling to liquid nitrogen temperatures indicating apparent “vitrification”. This approach offers a new and very promising technique for vitrification of cells using low levels of cryoprotectants. 相似文献
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Caglayan Berrak Kilic Ertugrul Dalay Arman Altunay Serdar Tuzcu Mehmet Erten Fusun Orhan Cemal Gunal Mehmet Yalcin Yulug Burak Juturu Vijaya Sahin Kazim 《Molecular biology reports》2019,46(1):241-250
Molecular Biology Reports - Traumatic brain injury (TBI) is the leading cause of mortality and morbidity in young adults and children in the industrialized countries; however, there are presently... 相似文献
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This study was designed to investigate the effects of Nigella sativa L. (NS), known as black seed, or/and Urtica dioica L. (UD), known as stinging nettle root, treatments on serum Na, K, Cl, and Ca levels and some hematological values of CCl4-treated rats. Sixty healthy male Sprague-Dawley rats, weighing 250–300 g, were randomly allotted into 1 of 4 experimental
groups: A (CCl4-only treated), B (CCl4+UD treated), C (CCl4+NS treated), and D (CCl4+UD+NS treated), each containing 15 animals. All groups received CCl4 (0.8 mL/kg of body weight, subcutaneously, twice a week for 90 d starting d 1). In addition, B, C, and D groups also received
the daily ip injection of 0.2 mL/kg NS and/or 2 mL/kg UD oils for 45 d starting d 46. Group A, on the other hand, received
only 2 mL/kg normal saline solution for 45 d starting d 46. Blood samples for the biochemical analysis were taken by cardiac
puncture from five randomly chosen rats in each treatment group at the beginning, d 45, and d 90 of the experiment. The CCl4 treatment for 45 d significantly (p<0.05) increased the serum K and Ca and decreased (p<0.05) the red blood cell count (RBC), white blood cell count (WBC), packed cell volume (PCV), and Hb levels without changing (p>0.05) the serum Na and Cl levels. NS or UD treatments (alone or combination) for 45 d starting d 46 significantly (p<0.05) decreased the elevated serum K and Ca levels and also increased (p<0.05) the reduced RBC, WBC, PCV, and Hb levels. It is concluded that NS and/or UD treatments might ameliorate the CCl4-induced disturbances of anemia, some minerals, and body’s defense mechanism in CCl4-treated rats. 相似文献