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1.
BackgroundLiterature data indicate the benefit of magnesium (Mg) supplementation. The aim of this study was to examine the effect of short-term Mg supplementation on iron status in healthy female participants.MethodsOne hundred healthy female students of the University of Belgrade - Faculty of Pharmacy participated the study during eleven intervention days. Students ingested Mg preparations with the same dose of the active substance. The analysis included the measurement of serum iron, unsaturated iron binding capacity (UIBC), total iron binding capacity (TIBC), total Mg (tMg), ionized Mg (iMg), complete blood count, met-, carboxyand oxy-haemoglobin (metHgb, COHgb, O2Hgb). Transferrin concentrations and percentage of transferrin saturation (SAT) were calculated manually. The association among the analyzed biochemical parameters was examined using polynomial regression. A principal component analysis (PCA) was used for the evaluation of interdependence between the analyzed parameters.ResultsA statistically significant trend for change in O2Hgb (%) by tertiles of iMg concentrations was found (P = 0.029). Serum tMg reached significant positive correlation with the SAT at concentration levels greater than 0.9 mmol/L, after 11 days of intervention (R2=0.116). Ionized Mg in a concentration higher than 0.6 mmol/L is positively correlated with SAT and serum Fe (R2=0.214; 0.199, respectively). PCA revealed variability of 64.7% for two axes after 11 days.ConclusionsMg supplementation leads to an improvement in the certain iron status parameters even in individuals with optimal levels of these indices. However, caution should be exercised when supplementing Mg, and laboratory monitoring of the interaction is required.  相似文献   
2.
精心设计教学活动,激发学生的学习兴趣   总被引:2,自引:0,他引:2  
肖军  李伟 《生物学杂志》2005,22(2):56-58
在生物学教学中通过设疑引起学生对知识的好奇;通过增加学生的认知冲突引起学生对知识的关注;以形象、生动的手段展示知识的魅力,让学生感受到知识的趣味:使学生在积极的情绪体验中产生兴趣。  相似文献   
3.
目的 为了解老年性骨质疏松情况,用超声骨密度仪对150例老年男性教师做跟骨超振幅衰减值的测试研究。方法:用DMS公怀UBIS5000型骨密度超声仪检查跟骨,研究受检者的年龄、体重、身高和巳患病咎与测得超声振幅衰减值(BUA),声速(SOS),骨硬度(STI)和相对骨折危险性(RRF)等参数之间的关系。结果:本仪器输出3种结果供医师参考:1.一幅灰阶图,2.一幅彩色图和曲线图,3.感兴趣区所测得的参数,受检者的平均BUA为63.87dB/MHz,SOS为1485.21m/s,本文数据经Statpal软件处理,得出回归公式:体重=189.1417 0.2062BUA-0.0224SOS,R=0.0466,P值有显著意义。结论:BUA值为主要参数,SOS为补充参数,作为评估老年男性教师的骨密度情况,假如BUA值突然下降则提示近期可能发生骨质疏松。  相似文献   
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Previous meta-analyses have shown that the hospital admission of older patients in acute geriatric units (AGU) compared to admission to other conventional units, significantly reduced the risk of functional deterioration during hospitalization, increasing the possibility of returning home, with an added reduction in cost of hospitalization. A new meta-analysis on the subject has recently been published in Age and Aging, which adds six new studies to the five clinical trials analyzed in previous meta-analyses. This article analyzes the results of this new meta-analysis, delving into the characteristics of the new studies included and making some considerations on the implications for care in the future development of AGU.  相似文献   
6.
Several studies suggest that season of birth differentially affects the physiological characteristics of humans. Those living at relatively high latitude, such as Canada, Spain, and Italy (44°N–45°N), and born in the fall tended to be “morning-type” persons in comparison to those born in other seasons. There are relatively little data on the affect of season of birth on people residing at low latitude. Here the authors show that at low latitude, Kochi, Japan (33°N), the effect of season of birth on the morningness chronotype is confined to young children aged 1–12 yrs, disappearing in elderly persons. Only female participants aged 2–12 yrs born in the fall, especially in November, were significantly morning-typed (p < .001) in comparison to those born in the other seasons, whereas there were no such significant season-of-birth differences in morningness-eveningness preference among male participants. Moreover, both female and male participants aged 13–25 yrs showed no significant seasonal differences in morningness-eveningness preference. The small effects detected in this study might be due to smaller seasonal change in day length at the relatively lower latitude of Kochi. (Author correspondence: )  相似文献   
7.
While there are many educational and experiential benefits to attending professional higher arts education programs, students who incur excessive student loan debt during their studies may experience unanticipated or poor professional outcomes either over the course of their artistic careers, shortly after the expiration of a loan grace period, or after they can no longer defer payments. To date, little to no research exists on the effects of an excessive student loan debt burden on professional arts careers. To address this gap in the higher arts education literature, and in an effort to facilitate scholarly discussion on the topic, this article identifies concerns, consequences, and potential interventions.  相似文献   
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9.
All physicians, at some point in their career, are responsible for the education of their peers and junior colleagues. Although medical students are expected to develop clinical and research skills in preparation for residency, it is becoming clear that a student should also be expected to develop abilities as a teacher. A handful of institutions have student-as-teacher programs to train medical students in education, but most students graduate from medical school without formal training in this area. When such a program does not exist, medical students can gain experience in education through participation in peer teaching, course design, educational committees, and medical education scholarship. In doing so, they attain important skills in the development, implementation, and evaluation of educational programs. These skills will serve them in their capacity as medical educators as they advance in their careers and gain increasing teaching responsibility as residents, fellows, and attending physicians.  相似文献   
10.
Abstract

Objective: The aims of this study are to investigate the association between: (i) forward head posture (FHP) and pressure pain thresholds (PPTs); (ii) FHP and maladaptive cognitive processes; and (iii) FHP and neck pain characteristics in university students with subclinical neck pain.

Materials/methods: A total of 140 university students, 90 asymptomatic and 50 with subclinical neck pain, entered the study. Demographic data, anthropometric data, FHP, and PPTs were collected for both groups. In addition, pain characteristics, pain catastrophizing, and fear of movement were assessed for participants with neck pain. FHP was characterized by the angle between C7, the tragus of the ear, and the horizontal line. Correlation analysis and multivariate regression analysis were conducted.

Results: Participants with subclinical neck pain showed significantly lower PPTs than participants without neck pain (p?<?.05), but similar FHP (p?>?.05). No significant association was found between FHP and PPTs in the asymptomatic group. In the group of participants with subclinical neck pain, PPTs at the right trapezius and neck pain duration explained 19% of the variance of FHP (R2?=?0.23; adjusted R2?=?0.19; p?<?.05).

Conclusion: This study suggests that FHP is not associated with PPTs in asymptomatic university students. In university students with subclinical neck pain, increased FHP was associated with right trapezius hypoalgesia and with neck pain of shorter duration. These findings are in contrast with current assumptions on the association between neck pain and FHP.  相似文献   
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