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61.
Science & Education - The purpose of the present study was to understand the nature of the link between science teachers’ epistemologies and their socioscientific issue (SSI) teaching... 相似文献
62.
Serap Cuhadar Mehmet Koseoglu Aysenur Atay Ahmet Dirican 《Biochemia medica : ?asopis Hrvatskoga dru?tva medicinskih biokemi?ara / HDMB》2013,23(1):70-77
Introduction:
Optimal storage of serum specimens in central laboratories for a long period for multicenter reference interval studies, or epidemiologic studies remains to be determined. We aimed to examine the analytical stability of chemistry analytes following numerous freeze-thaw and long term storage.Materials and methods:
Serum samples were obtained from 15 patients. Following baseline measurement, sera of each subject were aliquoted and stored at −20 °C for two experiments. A group of sera were kept frozen for up to 1, 2 and 3 months and then analyzed for stability. The other experiment consisted of one to ten times of freeze and thaw cycles. Total of 17 chemistry analytes were assayed at each time point. The results were compared with those obtained from the initial analysis of fresh samples. Median or mean changes from baseline (T0) concentrations were evaluated both statistically and clinically according to the desirable bias.Results:
Of the analytes studied, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK), gamma-glutamyl transferase (GGT), direct bilirubin, glucose, creatinine, cholesterol, triglycerides, high density lipoprotein (HDL) were stable in all conditions. Blood urea nitrogen (BUN), uric acid, total protein, albumin, total bilirubin, calcium, lactate dehydrogenase (LD) were changed significantly (P < 0.005).Conclusions:
As a result, common clinical chemistry analytes, with considering the variability of unstable analytes, showed adequote stability after 3 months of storage in sera at −20 °C, or up to ten times of freeze-thaw cycle. All the same, such analysis can only be performed for exceptional cases, and this should be taken into account while planning studies. 相似文献63.
Esra Eret-Orhan Ahmet Ok Yesim Capa-Aydin 《Asia-Pacific Journal of Teacher Education》2018,46(2):183-198
The study aimed to assess the adequacy of pre-service teacher education in Turkey as perceived by preservice teachers. Specifically, the researchers investigated preservice teachers’ perceptions of the adequateness of their education in terms of developing teaching skills and the major components of teacher education. The factors affecting their perceptions were also examined. In total, 1856 preservice teachers participated in the study. A questionnaire was prepared to collect data from the participants. According to the findings, teacher education should be enhanced in terms of preparing candidates for skills such as teaching in different contexts and cooperating with parents; and practicum hours needed to be improved for more effective preparation of preservice teachers. Moreover, it was also found that the preservice teachers’ subject, college, orientation towards teaching and the perceived adequacy of program components played significant roles in affecting their perceptions of teacher education. 相似文献
64.
Dielectrophoresis (DEP) is employed to differentiate clones of mouse melanoma B16F10 cells. Five clones were tested on microelectrodes. At a specific excitation frequency, clone 1 showed a different DEP response than the other four. Growth rate, melanin content, recovery from cryopreservation, and in vitro invasive studies were performed. Clone 1 is shown to have significantly different melanin content and recovery rate from cryopreservation. This paper reports the ability of DEP to differentiate between two malignant cells of the same origin. Different DEP responses of the two clones could be linked to their melanin content. 相似文献