A new principle to normalize plasma concentrations allowing single-sample clearance determinations in both children and adults

A sufficiently accurate quantification of renal function requiring only one plasma sample without an additional gamma-camera study has, until now, only been possible in adults. A new principle will be presented here allowing the universal application of known algorithms, regardless of the clearance substance used, by normalizing the plasma concentrations with respect to the individual body dimensions of the patients - for infants as well as for adults. In this respect, algorithms are developed for clearance determinations using technetium-99m mercaptoacetyltriglycine (^99mTc-MAG3), which are based on steady-state studies as the reference. They allow the calculation of quantitative clearance values in infants, requiring only one blood sampling at any time between the 25th and the 40th min postinjection. The comparison with a combined camera/two-plasmasample technique performed in 46 children aged between 9 days and 14 years (mean 6.05 years) resulted in a standard error of 8.5% from the line of identity (r = 0.94). Moreover, this procedure also increases the accuracy of results in adults.Dedicated to Professor Peter Georgi on the occasion of his 60th birthday Offprint requests to: B. Bubeck     

E-cigarettes: Are we renormalizing public smoking? Reversing five decades of tobacco control and revitalizing nicotine dependency in children and youth in Canada

An electronic cigarette (e-cigarette) is a battery attached to a chamber containing liquid that may (or may not) contain nicotine. The battery heats the liquid and converts it into a vapour, which is inhaled, mimicking tobacco smoking. The e-cigarette does not rely on tobacco as a source of nicotine but, rather, vaporizes a liquid for inhalation. E-liquids are often flavoured and may contain nicotine in various concentrations, although actual amounts are seldom accurately reflected in container labelling. The deleterious effects of nicotine on paediatric health are well established. The use of e-cigarettes in the paediatric age group is on the rise in Canada, as are associated nicotine poisonings. E-devices generate substantial amounts of fine particulate matter, toxins and heavy metals at levels that can exceed those observed for conventional cigarettes. Children and youth are particularly susceptible to these atomized products. Action must be taken before these devices become a more established public health hazard. Policies to denormalize tobacco smoking in society and historic reductions in tobacco consumption may be undermined by this new ‘gateway’ product to nicotine dependency.     

规范化的科室轮转在“5+3”背景下神经外科专业学位研究生培养模式中的改革研究

目前我国的神经外科住院医师规范化培训还没有形成健全的培训体系和教学机制,探索神经外科专业学位教育的新型人才培养模式。发现培养模式中的问题,以期更好地推进神经外科专业学位研究生的教育培养,提高培养的质量。只有这样才能真正培养出适合我国社会主义卫生工作需要的医疗实用性人才和医学高级专家。在新培养模式试点中,应该通过加强专业基础理论学习,强化临床实践能力;加强临床思维及创新能力的培养;建立专业的考核团队,负责全阶段的考核,基于以上方面对神经外科专业学位研究生培养模式进行探讨与改革。     

Normalization of CA19-9 Following Resection for Pancreatic Ductal Adenocarcinoma is not Tantamount to being Cured?

Background: Postoperative carbohydrate antigen 19-9 (CA19-9) is an independent predictor of survival forpancreatic ductal adenocarcinoma (PDAC), and more powerful than preoperative CA19-9. However, makingdecisions just dependent on postoperative CA19-9 may result in necessary treatments not being performed.Materials and Methods: A total of 178 patients with resected PDAC were eligible for this retrospective study,classified into two corresponding subgroups according to postoperative CA19-9. Prognostic significance of allclinicopathologic factors was evaluated by univariate and multivariate analyses. Results: Postoperative CA19-9,preoperative CA125 and lymph node status were independent predictors. Better predictive performances foroverall survival (OS) and recurrence-free survival (RFS) were achieved by postoperative CA19-9 comparedto preoperative CA125 and lymph node status. Particularly, preoperative CA125 was associated with poor OS(p<0.001 for the normalized CA19-9 patients, p=0.012 for the elevated) and RFS (p=0.005 for the normalized,p=0.004 for the elevated). Moreover, preoperative CA125 levels related with survival in double- negative patients.Conclusions: Normalization of CA19-9 is not tantamount to be cured. Preoperative CA125 is a critical predictorfor PDAC patients, especially in double-negative patients.     

Population coding under normalization

A common computation in visual cortex is the divisive normalization of responses by a pooled signal of the activity of cells within its neighborhood. From a geometrical point of view, normalization constraints the population response to high-contrast stimuli to lie on the surface of a high-dimensional sphere. Here we study the implications this constraint imposes on the representation of a circular variable, such as the orientation of a visual stimulus. New results are derived for the infinite dimensional case of a homogeneous populations of neurons with identical tuning curves but different orientation preferences. An important finding is that the ability of the population to discriminate between any two orientations depends exclusively on the Fourier amplitude spectrum of the orientation tuning curve. We also study the problem of encoding by a finite set of neurons. A central result is that, under normalization, optimal encoding can be achieved by a finite number of neurons with heterogeneous tuning curves. In other words, increasing the number of neurons in the population does not always allow for an improved population code. These results are used to estimate the number of neurons involved in the coding of orientation at one position in the visual field. If the cortex were to code orientation optimally, we find that a small number (∼4) of neurons should suffice.     

CorelDRAW在期刊制图工作中的规范化设置及应用技巧

【目的】提高期刊制图的效果和工作效率,促进期刊制图规范化。【方法】在制图工作中,应结合期刊版面的特点,制定完善的制图规范,从而统一期刊的制图风格,在工作中应注意总结CorelDRAW的应用技巧、积累图例样本,也应掌握其他制图软件的使用方法,做到协同运用多种制图软件制图,通过对制图软件功能的深入研究,提高工作效率和质量。【结果】期刊制图规范得到统一,工作质量和效率得到提升。【结论】CorelDRAW在期刊制图工作中存在很多需要掌握的功能技巧,需要制图编辑不断发掘。     

经导管闭合房间隔缺损的规范化探讨

1976年,King和Mills首次使用双伞形装置关闭房间隔缺损（ASD）,继后有多种封堵器在临床上应用,其中Cardioseal和Amplatzer封堵器应用较广泛,累计临床应用30000余例。戴汝平总结我国8家医院的6917例介入治疗的先心病中,ASD占30％,应用Cardioseal封堵器占10％,sidefis补片占5％,Amplatzer封堵器占85％。     

Normalizing gastrocnemius muscle EMG signal: An optimal set of maximum voluntary isometric contraction tests for young adults considering reproducibility

BackgroundEven though most studies normalize the surface EMG signal of the gastrocnemius muscle using a single position of maximum voluntary isometric contraction (MVIC), several studies tend to indicate that several positions are in fact needed to obtain a maximal voluntary activation (MVA) for most of the subjects. However, no combination of positions has already been described.Research questionA combination of MVIC positions to normalize the EMG signal of the gastrocnemius muscle is investigated. the influence of using several positions on the reproducibility of the normalization process is evaluated.MethodsTwenty healthy volunteers (45 % female – 55 % male, 25.4 years (SD 4.3), 72.6 kg (SD 13.9), 1.78 m (SD 0.12)) were recruited. Six positions for MVIC were compared and the effect of several normalization combinations on a functional task (gait) was evaluated.ResultsSeveral positions are needed to obtain at least 90 % of the MVA for 90 % of the volunteers even though the use of a single well-chosen position (unipodal standing position with knee fully extended and ankle fully plantar-flexed) will lead to no statistically significant differences of the gait evaluation during stance phase. For each position, five repetitions of the MVIC are recommended to obtain a valid MVA.SignificanceThis study confirms that using several MVIC positions is recommended when possible to normalize the gastrocnemius muscle EMG signal. However, in the situation of a patient where limited MVIC attempts are possible, using a single well-chosen position should not significantly influence the amplitude and the reproducibility of the measures.     

对社会组织参与新冠肺炎疫情常态化防控工作的思考

在党中央领导和全国人民艰苦努力下,我国新型冠状病毒肺炎疫情防控向好态势进一步巩固,疫情防控工作已从应急状态转为常态化。社会组织作为政府的补充力量,在新冠肺炎疫情常态化防控工作中发挥着重要作用。文章阐述了社会组织在疫情常态化防控的助力基层工作、开展心理援助、强化宣传教育、助力复工复产、监督恢复重建等参与路径,指出社会组织面临的困境并提出相关建议,以期为社会组织有效参与常态化疫情防控工作提供参考。