北京协和医院内科学系复合型精英医学人才培养探索

临床医学博士后项目是国家人力资源和社会保障部推行的复合型医学精英人才毕业后教育项目。2016年北京协和医院设立了临床医学博士后培养项目,内科学系在既往住院医师培养模式的基础上,创新设立了分层培养模式、阶梯式培养评估反馈体系、360°评价体系及危重症模拟培训课程等,并在实施过程中对项目进行持续改进和优化。本文对北京协和医院内科学系临床医学博士后培养项目运行实践进行总结,为培养具有国际视野的复合型医学精英人才提供借鉴和参考。     

A full-UV spectrum absorbing daily use cream protects human skin against biological changes occurring in photoaging

BACKGROUND: There is overwhelming evidence that exposure of human skin to ultraviolet radiations (UVR) leads to the development of cutaneous photoaging and eventually to neoplasia. This study was designed to evaluate in humans the protection afforded by a daily use cream containing a photostable combination of UVB and UVA absorbers (Uvinul N539, Parsol 1789 and Mexoryl SX) providing a continuous absorption through the entire UV spectrum, against damages induced by repeated daily exposure to solar simulated radiation (SSR). METHODS: Buttock skin of 12 healthy volunteers was exposed 5 days per week for 6 weeks to one minimal erythema dose of solar simulated radiation per exposure. The following parameters in treated and untreated skin were evaluated: erythema, pigmentation, skin hydration, skin microtopography, histology and immunochemistry, and collagen and metalloproteinase (MMP) mRNA levels. RESULTS: In SSR exposed unprotected skin sites, we observed melanization and changes in the skin hydration and microtopography. The epidermis revealed a significant increase in stratum corneum and stratum granulosum thickness. In the dermis, an enhanced expression of tenascin and a reduced expression of type I pro-collagen were evidenced just below the dermal epidermal junction. Although we were unable to visualize any change in elastic fibers in exposed buttock skin, a slightly increased deposition of lysozyme and alpha 1 antitrypsin on these fibers was observed using immunofluorescence techniques. Furthermore, types I and III collagen mRNA were slightly increased and a significant enhancement (up to 2.8-fold) of MMP-2 mRNA level was observed. The daily use cream was shown to prevent all these biological changes. CONCLUSION: Our results show in vivo that an appropriate full-UV spectrum product significantly reduces the solar-UV-induced skin damage, demonstrating the benefit of daily photoprotection.     

尾悬吊模拟失重大鼠肺组织细胞凋亡调控基因的研究

为研究尾悬吊模拟失重大鼠肺组织细胞凋亡调控基因的变化，采用尾悬吊模拟失重，分为悬吊7天和21天及相应对照4组，每组10只健康雄性SD，并采用原位杂交技术检测肺组织bcl-2/bax的表达情况。发现7天尾悬吊模拟失重大鼠肺组织bcl-2 mRNA水平明显低于对照组，两者之间差异有显著性意义（P＜0．05），但21天bcl-2 mRNA水平与对照组相比无显著性差异（P＜0．05）；7天尾悬吊模拟失重大鼠肺组织bax mRNA水平明显高于对照组，两者之间差异有显著性意义（P＜0．05），但21天bax mRNA水平与对照组相比亦无显著性差异（P＞0．05）。提示尾悬吊7天模拟失重大鼠肺组织细胞凋亡调控基因存在变化。     

小剂量高渗NaCl右旋糖酐液对高原创伤失血性休克大鼠血气及肺损伤的影响

文中报道了小剂量７．５％ＮａＣｌ／６％右旋糖酐－７０（ＨＳＤ）对模拟高原创伤失血性休克大鼠血气及肺组织损伤的影响。在大型低压舱内经股骨骨折，股动脉放血，５ｍｉｎ内使大鼠平均动脉压（ＭＡＰ）降至６．００±０．６７ｋＰａ，维持此血压水平１ｈ后，从股静脉分别输入４ｍｌ／ｋｇ的生理盐水（ＮＳ）、７．５％Ｎａｃｌ（ＨＳ）或ＨＳＤ，观察５ｈ。结果显示ＨＳＤ能明显减轻休克大鼠ＰＯ２、ｐＨ、ＨＣＯ下降的程度；ＨＳＤ治疗后５ｈ肺匀浆丙二醛（ＭＤＡ）、肺含水量低于ＮＳ及ＨＳ组，肺组织损害程度较ＮＳ及ＨＳ组轻。本研究表明ＨＳＤ对高原创伤失血性休克的早期救治有较高的实用价值。     

Handling characteristics of a palladium-free gallium-based alloy compared with a high copper dental amalgam in a simulated clinical trial

The aim of the current study was to compare the handling characteristics of a palladium-free gallium-based alloys (Galloy) with those of a high-copper amalgam (Permite C). The study had a particular interest in the evaluation of the direct placement delivery system used with both alloys. Ten dentists participated in the current study. Each placed two amalgam and two gallium-based alloy restorations in conventional class II cavities prepared in acrylic typodont teeth. None of the participating dentists had used the direct placement delivery system or had any previous experience with gallium-based alloy and no practice was allowed beforehand. The restorations were evaluated according to the following criteria: ease of loading the cavity (delivery system), ease of condensation, capacity to produce and sustain contact area, ease of carving, resistance to damage during removal of the matrix band, overall quality of the restoration and the available working time. Each criterion was given a score on a scale of 1-5 (1: very poor, 2: poor, 3: fair, 4: good, 5: very good). The results showed no statistically significant difference in the evaluated criteria between the two alloys (P > 0.05) except for criterion number 2 (ease of condensation, P=0.0005).     

Simulated Zenker's Endoscopic Staple‐Assisted Esophagodiverticulostomy (ESED) Surgery

Purpose The process of learning new surgical procedures remains a challenge in otolaryngology–head and neck (OHN) surgery. Endoscopic surgery for Zenker's diverticulum presents a dilemma mandating simulated surgery because there is no animal model or cadaver situation resembling the pathologic condition. Study Design The author has developed an inexpensive model for ESED using a utility latex glove to provide a simulated pharynx with a Zenker's diverticula. Methods First, the thumb and index finger are isolated with a staple line and a rubber band is placed around the long and ring fingers to simulate the cricopharyngeus muscle. The long finger, which will act as the larynx, is cannulated with a noncompressible endotracheal tube. The ring finger then simulates the esophagus and the little finger, the Zenker's diverticular pouch. The glove and the endotracheal tube are positioned inside a 1‐ft length of 3‐in polyvinyl chloride (PVC) pipe. A bivalving laryngoscope is suspended to visualize the “postcricoid area” and the parting wall. The rubber band pulls the inferior aspect of the “esophagus” up against the “larynx,” simulating the tight cricopharyngeal segment. Using video‐telescopic control, the endoscopic stapler is used in the standard fashion as described for ESED. Results This model provides an opportunity for OHN surgeons to become familiar with endoscopic stapling and suturing devices, and experience the difficulty of using long telescopes, suspension laryngoscopes, and staplers in a confined area. Conclusion Part of the experience of endoscopic surgery of the pharynx can be gained through an inexpensive simulation of a Zenker's diverticulum.     

模拟失重大鼠裸露心肌纤维的张力－pCa关系

目的：观察４周尾部悬吊法模拟失重是否影响大鼠心肌肌钙蛋白Ｃ对Ｃａ￣（２＋）的亲和力，方法：用１％ＴｒｉｔｏｎＸ－１００制备裸露心肌纤维、观察心肌肌原纤维的张力－ｐＣａ关系．结果：对照与４周模拟失重组大鼠心肌肌原纤维的张力－ｐＣａ关系保持不变，其ｐＣａ＿５０值分别为６．１５±０．０４与６．０６±０．０７，两组均值间无显著差别（Ｐ＞０．０５）；Ｈｉｌｌ系数ｎ分别为２．４８±０．１７与２．８５±０．２４，两值间亦无显著差别（Ｐ＞０．０５）；但模拟失重组最大张力却较对照组降低１８．６％（Ｐ＜０．０５）．结论：模拟失重并未影响心肌肌钙蛋白Ｃ对Ｃａ￣（２＋）的亲和力；心肌收缩性能降低、舒张时程缩短并不是由于这一机理的改变引起的．     

医学成人学历教育计算机模拟病例辅助考核系统研究

介绍了本院开发的医学成人学历教育计算机模拟病例辅助考核系统，它有成人医学教育特点，知识点涵盖面全，经济实用，为测评成人医学生临床实践能力提供了一种贴近临床实际、客观公正的考评手段。该系统具备以下基本功能：系统设置模块；病例库管理模块；考试管理模块；考试分析模块。     

模拟微重力条件下心肌细胞骨架图像的直方图特征分析

目的 微重力环境会影响心肌细胞的细胞骨架形态的分布。我们试图利用灰度方差、偏度及峰度等直方图参数量化模拟微重力条件下培养细胞的微管图像的形态分布特征。方法 分别对模拟微重力条件下培养的心肌细胞(回转组)和正常条件下培养的心肌细胞(对照组)细胞骨架的微管图像提取灰度直方图统计特征，同时比较了利用quercetin对抗模拟微重力的实验组(加药组)的微管图像的直方图特征参数。结果 对3组细胞骨架图像的特征分析表明所选的3个特征参数能很好地量化各实验组微管的灰度特征。笔者还讨论了各实验组的组间均差，并利用Fisher准则对实验组进行多元分析，结果表明图像的直方图特征参数对细胞骨架的定量分析有很大的参考价值。结论 微重力环境中生物细胞骨架的形态发生弥散性变化，图像的直方图特征参数可以作为其定量分析的工具。     

常压模拟高住低练对大鼠血清自由基及一氧化氮的影响

目的:探讨常压下模拟高住(海拔3000m)低练对大鼠血清自由基代谢及NO的影响.方法:40只雄性SD大鼠随机分为四组,分别为低住安静组、低住低练组、常压高住安静组和常压高住低练组,测定4周后的大鼠血清超氧化物歧化酶(SOD)、丙二醛(MDA)及一氧化氮(NO)变化.结果:4周常压模拟高住低练使大鼠血清SOD较低住低练组显著升高(P＜0.01);NO较常压高住安静组极显著升高(P＜0.01),与低住低练组相比无显著性差异;MDA较低住低练组极显著降低(P＜0.01).结论:4周常压模拟高住低练可以显著提高大鼠血清 SOD、NO活性,降低血清脂质过氧化物水平.