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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   
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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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Objectives:Access to high-quality information improves the quality of patient care, but lack of time and sufficient skills in information seeking can prevent access to information by clinicians. To solve this problem, clinical informationists can provide high-quality, filtered information for clinical team members. This study identified the core competencies that clinical informationists need to effectively fulfill their roles on clinical teams.Methods:Participants were selected purposefully from clinicians and medical librarians. Data were collected through semi-structured interviews and analyzed using qualitative content analysis.Results:The authors identified six competencies—communication, research, education and training, domain knowledge, information services, and technology—which together were used to develop a “CREDIT” model of core competencies for clinical informationists.Conclusions:The CREDIT model can be used as criteria for evaluating the performance of clinical informationists as well as for developing and assessing clinical informationist educational programs and curriculums.  相似文献   
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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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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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The purpose of the present study was to investigate the impact of feedback on writing accuracy over time and examine the relevance of the students’ mother tongue to the feedback effect. To this end, the study compared two groups of Iranian English majors (N = 56) over a period of four months: one with indirect grammar feedback and the other with no grammar feedback whatsoever. The results of the study did not show a significant effect for the teachers’ feedback. However, the results showed a main effect for practice and the interaction of practice and feedback as a result of which both groups improved their writing accuracy over the course of one semester, with the feedback group making more improvement. The results also showed significant differences between the two groups in reducing their errors in various grammatical categories. The study further revealed that the success ratio of error reduction in each category was highly sensitive to cross-linguistic differences. The students’ views, elicited after the study, support the findings obtained from the analysis of the quantitative data.  相似文献   
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Reforms in education often fail due to insufficient time to implement them, too few charismatic leaders, the influence of the preceding culture, scarce resources or an incapacity to comprehend the complexity of the education system. Most studies dealing with the cognitive aspects of educational change investigate the meaning of change through the lens of the educators and principals and there is not as much research available on the perception and interpretation of change by policy makers and the language they use to communicate messages about policy that affect sensemaking–sensegiving during the process of learning about the changes. Guided by the premise that the language of a reform movement is shaped by its ideology, this article illustrates how press releases of the Ministry of Education in Canton Sarajevo in Bosnia–Herzegovina reflect an exploitation-oriented dominant reform logic. The results of frequency analysis, hierarchical clustering and multidimensional scaling imply that MoE is driven by a top-down perspective to educational change, with a focus on the procedural, organizational and collaborational aspects of reforms that primarily alter the structure of the education system but not its internal substance. We end this paper by suggesting that educational system as complex adaptive system cannot be controlled, but effectively managed through distribution of control and creation of few attractors, benefiting from self-organization in the technical core and making change in the official top-down rhetoric.  相似文献   
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This paper studies the neural adaptive control design for robotic systems with uncertain dynamics under the existence of velocity constraints and input saturation. The control objective is achieved by choosing a control Lyapunov function using joint error variables that are restricted to linear growth and furthermore by introducing a secant type barrier Lyapunov function for constraining the joint rate variables. The former is exploited to bind the forward propagation of the position errors, and the latter is utilized to impose hard bounds on the velocity. Effective input saturation is expressed, and neural networks are employed to tackle the uncertainty problem in the system dynamics. Feasibility conditions are formulated, and the optimal design parameters are obtained by solving the constrained optimization problem. We prove that under the proposed method, semi-global uniform ultimate boundedness of the closed-loop system can be guaranteed. Tracking errors meanwhile converge to small neighborhoods of the origin, and violations of predefined velocity constraints are avoided. Finally, numerical simulations are performed to verify the effectiveness of the theoretical developments.  相似文献   
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