Use of the Optomap with lid retraction and its sensitivity and specificity#

Background: Optomap uses the ultra‐wide field scanning laser ophthalmoscopy to provide retinal examination. It permits fundus examination without the use of a mydriatic, which is more comfortable for the patients. This paper determines the sensitivity and specificity of the Optomap for detecting retinal signs under non‐mydriatic conditions. Methods: Fifty‐four eyes identified with retinal/choroidal signs and eight normal eyes were recruited from 31 Hong Kong Chinese subjects. Photo‐documentation of fundal changes was obtained with the Optomap under non‐mydriatic conditions before a dilated fundus examination by a clinician using standard procedures. The eyelid was retracted using a cotton bud when necessary. Dilated fundus examinations were performed by another clinician using binocular indirect ophthalmoscopy and slitlamp biomicroscopy with a fundus lens. The Optomap images were evaluated by four other investigators under masked condition. The International Classification of Disease, Ninth Revision (ICD‐9‐CM) was adopted for recording retinal features. Screening results were compared with those obtained using the dilated fundus examination as the gold standard. Results: The cotton bud method for eyelid retraction showed an improvement in the area of retina that could be visualised. The sensitivity and specificity of the Optomap averaged 76.4 and 71.9 per cent, respectively. Some fundal signs were missed by all observers in the Optomap but not with the biomicroscope. These included white‐without‐pressure, lattice degeneration, paramacular drusen and pigmentary changes at central fundus. Conclusion: Optomap serves as a reliable screening tool for fundus examination especially because it covers a much wider area of the peripheral retina than other digital instruments for fundus photography.     

Recruitment of anterior dorsolateral prefrontal cortex in human reasoning: a parametric study of relational complexity

Reasoning and problem solving depend on the ability to represent and integrate complex relationships among stimuli. For example, deciding whether an animal is dangerous requires integrating information about the type of animal, its size, its distance from oneself, and one's proximity to shelter. Relational complexity increases with the number of such interdependent elements that must be simultaneously considered to solve a problem. We used functional magnetic resonance imaging to identify brain regions that respond selectively in processing high levels of relational complexity. Performance on nonverbal reasoning problems in which relational complexity was varied parametrically was compared with performance on control problems in which relational complexity was held constant while difficulty was manipulated by adding distractor forms to the problems. Increasing complexity and adding distractors both led to increased activation in parietal and in dorsolateral prefrontal cortex, with high levels of relational complexity selectively activating anterior left prefrontal cortex. Our data provide evidence that brain regions specific to integrating complex relations among stimuli are distinct from those involved in coping with general task difficulty and with working-memory demands.     

Unfolding the human hippocampus with high resolution structural and functional MRI

The hippocampus is a region of the brain that is crucial to memory function. Functional neuroimaging allows for the noninvasive investigation of the neurophysiology of human memory by observing changes in blood flow in the brain. We have developed a technique that employs high-resolution functional magnetic resonance imaging (fMRI) in combination with cortical unfolding to provide activation maps of the hippocampal region that surpass in anatomic and functional detail other methods of in vivo human brain mapping of the medial temporal lobe. We explain the principles behind this method and illustrate its application to a novelty-encoding paradigm.     

基因重组神经营养蛋白-3的生物学活性

目的：测定ＮＴ－３ｃＤＮＡ／ＣＨＯ细胞表达的基因重组ＮＴ－３的生物学活性。方法：体外培养８日龄鸡胚背根神经节（ＤＲＧ）,加入条件培养基,测量背根节神经突起生长的长度。结果：ＮＴ－３ｃＤＮＡ／ＣＨＯ细胞培养４８ｈ后的无血清条件培养基１：２４稀释后即能促进ＤＲＧ神经突破的生长;随着其中ＮＴ－３浓度增加,神经突破长度也逐渐延长,有明显的量效关系;ＤＲＧ培养４８ｈ长出的神经突破与２４ｈ相比,明显长而致密;     

大鼠红细胞流变性变化及抗运动疲劳效应与补服肉碱和糖的作用

目的:观察单独和配合补充肉碱和糖对大鼠红细胞流变性及抗运动疲劳能力的影响。方法:实验于2005-09/11于河北师范大学体育学院运动生理学实验室完成。①选用SD雄性大鼠72只,按随机数字表法分为4组:安静组(n=6)、安静补服组(n=18)、安慰运动组(n=12)和补服运动组(n=36)。安静补服组和补服运动组均给予3种药物形式:左旋肉碱(由沈阳东宇精细化工有限公司生产)、葡萄糖(济南利民制药有限公司生产)、肉碱和葡萄糖。安静补服组和补服运动组每天上午8∶30给予自来水溶解的肉碱和/或糖补剂,安静组和安慰运动组给予相同量的自来水。连续补充7d,补服量:肉碱组、葡萄糖组、肉碱 葡萄糖组分别为650mg/(kg·d),7g/(kg·d),325mg/(kg·d) 3.5g/(kg·d)。②在实验第8天,将安静组取血4mL。安慰运动组和补服运动组进行无负重游泳至力竭,然后取血。采用北京泰诺德新技术研究所生产的BV-100型无摩擦式血液流变仪测全血高切黏度(180s-1)、全血高切还原黏度(180s-1)、全血低切黏度(3s-1)、全血低切还原黏度(3s-1)、刚性指数及聚集指数。③计量资料进行正态分布、方差齐性检验后,再进行方差分析。结果:大鼠72只均进入结果分析。①红细胞流变性指标变化:安静补服组各组虽大部分红细胞流变性指标有改善,但与安静组相比,差异无显著性意义(P>0.05)。安慰运动组运动后5min全血高切黏度和全血高切还原黏度明显高于安静组(P<0.01),运动24h后全血高、低切黏度和红细胞聚集指数明显高于安静组(P<0.01)。一次力竭运动后5min各补服运动组全血低切黏度明显低于安慰运动组(P<0.01)。各组间红细胞刚性指数和红细胞聚集指数差异不明显(P>0.05)。各补服运动组间相比,补服肉碱组的全血低切还原黏度最高(P<0.01)。各补服运动组运动后24h全血低切还原黏度和红细胞聚集指数明显低于安慰运动组(P<0.05～0.01),补服肉碱和肉碱 葡萄糖运动组全血低切还原黏度和全血低切黏度、红细胞聚集指数明显高于补服葡萄糖运动组(P<0.05～0.01)。②抗疲劳作用:补服肉碱、葡萄糖、肉碱 葡萄糖运动组大鼠游泳时间分别为(334.5±27.81),(321.0±51.83),(326.5±39.9)min,均长于安慰运动组[(252.5±42.69)min,P<0.01];各补服运动组间差异不明显(P>0.05)。结论:单独补充或合用肉碱和糖均有利于力竭运动后大鼠红细胞流变性指标的改善,导致其运动能力的提高。     

雪灵芝对二乙基亚硝胺诱导大鼠肝癌组织细胞的抑制作用

目的：验证雪灵芝是否具有抑制大鼠肝癌的功效。方法：实验于2003—09/2004—08在广西疾病预防控制中心SPF级动物实验室完成。选用健康成年SD大鼠160只。按体质量分层随机分为5组：空白对照组、模型组、雪灵芝高剂量组、雪灵芝中剂量组和雪灵芝低剂量组，每组32只。雪灵芝高、中、低剂量组大鼠分别灌胃2．500，1．250，0．625mL/kg雪灵芝溶液，阴性对照组和模型组灌胃等量蒸馏水，1次／d，连续60d。第61天开始雪灵芝高、中、低剂量组和模型组灌胃二乙基亚硝胺溶液，对照组灌胃等量的生理盐水。于停止灌胃90d后各组处死一半受试大鼠（雌雄各半），检测血常规及血清主要生化指标，观察各脏器大体形态改变、脏器的癌变程度。1周后给剩余大鼠灌胃雪灵芝溶液（不含二乙基亚硝胺）。7周后处死余下的一半雄性大鼠，进行相同操作。8周后处死余下的全部大鼠，操作及检测方法同前。结果：纳入的160只SD大鼠，145只进入结果分析，15只脱落。①病理切片检查结果：除阴性对照组，其他各组大鼠肝组织均发生癌变或癌前病变。雪灵芝高、中、低剂量组的癌前病变发生率与模型组相近（P〉0．05）；癌变的发生率均低于模型组，差异有显著性意义（P〈0．05，0．01）。②大体标本检查结果：阴性对照组大鼠肝脏的大体标本均无异常改变，其他各组大鼠的肝脏有些可见表面粗糙等病理改变。模型组大体标本病理改变的阳性率高于雪灵芝高、中、低剂量组，差异有显著性意义（P〈0．05）。肉眼观模型组癌变发生率高于其他各组。③其他脏器检查结果：模型组2只大鼠有肝癌肺转移。结论：以较大剂量的二乙基亚硝胺连续灌胃30d可以复制大鼠肝癌模型；雪灵芝对二乙基亚硝胺诱导的大鼠肝癌具有预防和抑制的作用。     

表皮细胞培养及其临床应用

目的:对表皮细胞的培养方法、临床应用进展方面的研究成果进行综述,展望其发展趋势。资料来源:应用计算机检索PubMed数据库1970-01/2006-08相关表皮细胞的文献,检索词“keratinocytes,culture,skin grafting”,同时检索中国期刊网2000-01/2006-08期间的相关文献,检索词为“表皮细胞,培养,皮肤移植”。资料选择:对资料进行初审,选取相关文献查找全文。纳入标准:①表皮细胞的培养。②表皮细胞的移植。排除标准:综述文献、重复研究类文章。资料提炼:共收集到30篇符合标准的文献,英文文献26篇,中文文献4篇,其中与培养相关的文献19篇,与移植相关的文献11篇。资料综合:自1975年以来,表皮细胞从最初的有血清、有滋养层培养,到无血清、无滋养层培养,再到后来的自动化培养。其培养方法有了较大的发展。这些发展促进了其临床应用,从细胞悬液移植到自、异体细胞膜片移植,再到表皮细胞-生物材料复合物移植。培养和移植方法的发展使人们在治疗大面积皮肤缺损方面看到了希望。结论:目前在表皮细胞培养及其临床应用上还有不少问题需要解决,但随着表皮细胞培养方法和技术的进一步完善,特别是与纳米科学、材料科学等学科的交叉,定能在不远的将来获得理想的永久性皮肤替代物。