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Maedeh Koohi Moftakhari Esfahani Seyed Ebrahim Alavi Fatemeh Movahedi Fatemeh Alavi Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2013,28(4):358-360
Regarding that the breast cancer is the most prevalent disease among women, paclitaxel, an anti-cancer drug, could be used in treatment of this disease. As paclitaxel has adverse effects, it was used of nanoliposome drug delivery technology in order to reduce adverse effects and improve drug efficacy. Certain ratios of phosphatidylcholine, cholesterol and paclitaxel were synthesized to prepare nanoliposomal paclitaxel. Using Zeta sizer device, the mean diameter of nanoliposomal paclitaxel was obtained 421.4 nm and its encapsulation efficiency was 91.3 %. By dialysis, drug release in nanoliposome paclitaxel formulation within 28 h was studied which was 5.53 %. This study showed that cytotoxicity effect of nanoliposomal paclitaxel is more than that of the standard form. 相似文献
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Nasser Mansour 《International Journal of Science Education》2013,35(7):1230-1275
To gain a better understanding of teachers’ beliefs about teaching, as compared with their in-reality classroom practices, case studies were constructed with four science teachers in different schools in Egypt. The main aims of this article were to provide an answer to the research question, ‘To what extent do science teachers’ beliefs correspond to their practices?’ and to explore the contextual factors that can explain the difference, the consistency or inconsistency, between teachers' beliefs and practices. The study collected data for each teacher using semi-structured interviews, notes taken while observing classes, and teachers’ notes, journals, and lesson plans concerned with STS lessons. The data were analysed using the constant comparative method around common themes, which were identified as distinctive features of teachers’ beliefs; these same themes were then compared with their practices. Results showed that a few of the in-service science teachers’ pedagogical beliefs aligned with constructivist philosophy. Some of the teachers’ beliefs were consistent with their practices, especially the traditional beliefs, while some of teachers’ practices were conflicted with their beliefs in different contexts. 相似文献
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Nasser Mansour 《Research in Science Education》2013,43(1):347-369
A growing body of research argues that teachers’ beliefs and practices should be studied within the sociocultural contexts of their work because the relationship between their beliefs and practices is both complex and context-dependent. There is a need for further research in this area in understudied contexts such as developing countries, in order to promote effective education in schools and the professional development of teachers. This paper argues that if this ‘black box’ of sociocultural contexts in which science teachers are embedded is better understood, it may be possible to identify specific aspects of these contexts related to educational organizations that act as either supports or barriers to pedagogical reform or to implementing innovations in science education. Consequently, the main purpose of this study is to explore the sociocultural contexts of ten Egyptian science teachers and to what extent these sociocultural contexts help in understanding teachers’ pedagogical beliefs and practices. This paper, by utilizing a multi-grounded theory approach and qualitative methods, reveals a variety of sociocultural contexts that are related to teachers’ pedagogical beliefs and practices. 相似文献
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Hasan Ebrahimi Shahmabadi Seyed Kazem Bagherpour Doun Seyed Ebrahim Alavi Mehri Mortazavi Zahra Saffari Maryam Farahnak Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2014,29(3):357-361
Emulsion polymerization was used to synthesize poly butyl cyanoacrylate nanoparticles in presence of steric stabilizer dextran 70. Nanoparticles were characterized by particle size analysis, scanning electron microscopy and light microscopy. Polymerization factors affecting particle size and distribution such as dextran 70, polysorbate 80 (PS 80) and H+ concentration, polymerization time and temperature, and sonication were studied. Distinct concentrations of stabilizer were needed to produce proper nanoparticles. In this case, the appropriate value was 2 % of total volume. At pH 4 significant decrease in production efficiency demonstrated the substantial effect of H+ concentration on nanoparticles. Furthermore significant increases in particle size and distribution was observed at 50 °C compared to room temperature. 0.001 % (v/v) PS 80 represented notable influence on size and distribution. In addition, shaped nanoparticles were obtained by altering polymerization time from 5.5 h to 18 h. Finally, nanoparticle features were influenced by different factors. Appropriate manipulating of such factors can lead to obtaining desirable nanoparticles. 相似文献
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Neda Dadgar Maedeh Koohi Moftakhari Esfahani Sepideh Torabi Seyed Ebrahim Alavi Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2014,29(4):501-504
This study is aimed to investigate the nanoliposomal artemisinin preparation, and its implementation on breast cancer cells. Side effects have been one of the common challenges of drug usage, as well as cancer treatment. In order to reduce such effects, nanotechnology has been a great help. Nanoliposomes are provided through reverse phase evaporation. In this method, certain proportions of phosphatidylcholine, cholesterol and artemisinin were mixed together. Besides, the obtained formulation was pegylated by using polyethylene glycol 2000 in order to increase its stability and solubility. The mean diameter of non-pegylated and pegylated liposomal artemisinin was determined by Zeta sizer system. The percent of drug released from liposome was performed by dialysis. The encapsulation efficiency of both formulations was estimated by spectrophotometry method. As a result, encapsulation and drug release of nanoliposomal formulation were more than the pegylation of the same formulation. In addition, this study indicated that cytotoxicity effect of pegylated nanoliposomal artemisinin was more, in comparison with nanoliposomal artemisinin. 相似文献
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Seyed Ebrahim Alavi Maedeh Koohi Moftakhari Esfahani Fatemeh Alavi Fatemeh Movahedi Azim Akbarzadeh 《Indian journal of clinical biochemistry : IJCB》2013,28(3):299-302
It is clear that cancer is one of the most mortal diseases in the world and the most prevalent among women is breast cancer. As hydroxyurea (HU)—a drug which is used in chemotherapy—has many adverse effects in long-term despite of its therapeutic properties, we made use of nano drug delivery technology in order to reduce adverse effects and increase therapeutic index. Thus, liposomation is a novel way in drug delivery systems. In this study a mixture of phosphatidylcholine and cholesterol was mixed and HU was added to the resultant mixture. The mean diameter of the nanoliposomal HU measured with the Zeta Sizer device (equal to 402.5 nm) and its encapsulation efficiency was 70.8 %. Besides, using dialysis, the pattern of drug release from nanoliposomes has been studied and the results showed that the drug release of nanoliposomal drug within 28 h was equal to 25.85 %. This study showed that the cytotoxicity effect of nanoliposomal drug is more than that of the standard drug. 相似文献
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Delayed-onset muscle soreness refers to the skeletal muscle pain that is experienced following eccentric exercise. The aim of the present study was to examine the physiological effects of physical activity with or without ibuprofen on delayed onset muscle soreness. Forty-four non-athletic male volunteers (age 24.3?±?2.4 years) were randomly assigned to one of four groups: physical activity (n = 11), ibuprofen (n = 11), physical activity and ibuprofen (combination, n = 11), or control (n = 11). The physical activity programme comprised 5?min of walking and jogging, 10?min of static stretching of the hands and shoulder girdle, and 5?min of concentric movements with sub-maximal contractions. The total amount of ibuprofen consumed by a single individual was 2800?mg; this was taken from 1?h before the eccentric actions up to 48?h after it. Delayed onset muscle soreness was induced by performing 70 eccentric contractions of the biceps muscle of the non-dominant side on a modified arm curl machine. Perceived muscle soreness, maximal eccentric contraction, creatine kinase enzyme activity and elbow range of motion were assessed 1?h before and 1, 24 and 48?h after the eccentric actions. The results indicated that, after the eccentric actions, soreness increased (P?<?0.001) across time in all groups, with the highest values being recorded at 24?h. At 24 and 48?h, greater soreness (P <?0.001) was observed in the control group than in the physical activity and combination groups. After the eccentric actions, creatine kinase increased and was elevated (P?<?0.001) compared with baseline in all groups, with values returning to baseline in the physical activity and combination groups by 48?h. However, creatine kinase in the control and ibuprofen groups was still significantly higher than at baseline after 48?h. Creatine kinase was higher (P?<?0.001) in the control group than in physical activity and combination groups at 24 and 48?h. There was also a reduction (P?<?0.001) in elbow range of motion across time. This reduction in elbow range of motion was greater (P?<?0.001) in the control and ibuprofen groups than in the physical activity and combination groups at 1, 24 and 48?h. The reduction in maximum eccentric contraction was greater (P?<?0.001) in the control and ibuprofen groups than in the physical activity group at 24 and 48?h and the combination group at 48?h. In conclusion, the results add to our understanding of the effects of physical activity and the combination of physical activity and ibuprofen in reducing the severity of muscle soreness induced by eccentric exercise. Physical activity conducted before eccentric exercise alleviates muscle soreness. Our results indicate that physical activity with or without ibuprofen helps to prevent delayed-onset muscle soreness. 相似文献