电位滴定法测定胰激肽释放酶活力测试条件探讨

本文用ＦＩＰ推荐的方法，以具有国际单位的参照品为标样，滴定液为０．０１ｍｏｌ／ＬＮａＯＨ标准溶液，考查了以ＢＡＥＥ为底物的电位滴定法测定胰激肽释放酶活力的实验条件，通过正交试验得出直观和方差分析的结果，依据酶活力单位高、ＳＤ和ＲＳＤ％较小的原则，求出酶活力测定的最适条件是：酶反应温度为２５℃；缓冲液为０．００１５ｍｏｌ／ＬＮａ２Ｂ４Ｏ７－０．２５ｍｏｌ／ＬＮａＣＬ－２×１０（－４）ｍｏｌ／ＬＥＤＴＡ，ｐＨ为８．００；反应液中酶浓度为０．４８ＩＵ／ｍｌ；底物浓度为５×１０（－３）ｍｏｌ／Ｌ；胰蛋白酶抑制剂浓度为１２５μｇ／ｍｌ。胰激肽释放酶活力测定的实验数据的相对标准偏差小于５％。     

人工晶体植入屈光度的术前预选法：眼科超声仪36例对比研究

根据公认的眼科解剖学数据，提出后房型人工晶体植入屈光度的术前预测方法：IOL（D）=1．02（＋21D＋2X）。经人工晶体专用眼科A超36眼实测对比，无显著差异，认为在地市级医院和县级医院后房型人工晶体植入术推广中具有积极意义。     

苯作业工人白细胞降低者的总估校正现患率

选择乡镇工业苯作业工人４次外周血白细胞计数中的间隔半年的两次数据，应用俘获再俘获法，计算其白细胞降低者的总估校正现患率（ＡＣＰＲ）。结果苯接触组为３６．８ｌ％（２９．１４％～４４．４８％），对照组为１２．７１％（７．２０％～１８．２２％）具有显著差异，其相对危险度为２，９。用常规法求得的４次检出率分别是：苯接触组为２６．３７％，１８．７３％，２７．９３％，３６．７６％；对照组为６。８５％，７．３８％，７．９４％，１５．００％。均在其ＡＣＰＲ之９５％可信限内，可见ＡＣＰＲ计算方法简便、结果准确，值得推广。对于稳定的人群，可用其每年一次的健康监护资料计算ＡＣＰＲ。     

Ontogenesis of the pyramidal cell of the mammalian neocortex and developmental cytoarchitectonics: a unifying theory.

The prenatal development of the mammalian neocortex has been analyzed, with the rapid Golgi method, in a variety of experimental animals (hamster, mouse, rat, and cat) and in humans. A new developmental conception of the structural organization of the mammalian neocortex is discussed. Neocortical development begins with the establishment of the primordial plexiform layer (PPL) which precedes and is a prerequisite for the subsequent formation of the cortical plate (CP). The formation of the CP occurs, in its entirety, within the PPL. During its development, three fundamental neuronal events occur: migration, early differentiation, and late maturation. All migrating neurons, travelling on radial glial fibers, reach layer I, develop an apical dendrite, and establish contacts with its elements. These newly differentiated neurons assume similar morphology resembling embryonic pyramidal cells. As such, an early differentiation stage common to all neurons of the CP is established. During the late maturation stage, all CP neurons acquire their specific phenotypic structural and functional features. Only pyramidal neurons retain and expand their original connections with layer I while other neuronal types lose these connections. The pyramidal cell is redefined in developmental terms: the neocortex's pyramidal cell is both structurally and functionally locked into position between layer I and the cortical depth of its soma. During mammalian evolution pyramidal cells are forced to structurally and functionally elongate their apical dendrite outwardly to accommodate an increasing amount of information without losing either their original anchorage to layer I or their cortical depth. This unique property of pyramidal neurons is considered to be a mammalian innovation. Based on these observations, a unifying developmental cytoarchitectonic theory applicable to all mammals is proposed. The theory considers the CP to be a mammalian innovation and to represent a single, stratified, and expanding telencephalic nucleus. The theory envisions the mammalian neocortex as an open biological system capable of progressive expansion by the recruitment and transformation of primitive neurons from upper layer II into pyramidal cells. Hence, the number of pyramidal cell strata increases over the course of mammalian phylogeny. The developmental roles of layer I in the migration of neurons, formation of the CP, unique morphology of pyramidal cells, and overall structural organization of the mammalian neocortex are emphasized.     

线宽增量法及其在生物材料发射光谱分析中的应用

作者利用交流电弧和光栅摄谱仪组装了能够绘制谱线轮廓曲线和准确测定谱线宽度的记录仪,用线宽增量法对生物材料(拟血清)中的主要成分Ca和微量元素Cu进行了测定。与黑度法相比,本实验结果的线性好,误差小,再现性有所提高。这些结果表明,用上述仪器装置和线宽增量法进行生物材料含量分析优于黑度法。     

Path analysis and sib-pair linkage

When the distance between linked loci is expressed in terms of the correlation between the identity-by-descent (idb) values of the loci, then a path model may be used to order loci with data on sib-pairs and their parents. The relationship between the recombination fraction and the correlation coefficient is developed and a method for fitting a covariance matrix predicted by a specific ordering of loci to an observed covariance matrix is proposed. © 1993 Wiley-Liss. Inc.     

Mouthguards: difference in longitudinal dimensional stability between single- and double-laminated fabrication techniques

Abstract –  Though the use of mouthguards (MGs) has increased with the increase in sporting activities, little is known about the influence of their fabrication methods on longitudinal dimensional stability. The objective of this study was to compare the difference in the longitudinal dimensional stability between single and laminated MGs. Single-layer MGs were made from a 4.0 mm thick ethylene vinyl acetate (EVA) sheet and laminated MGs were made from two 2.0 mm thick sheets of EVA. MGs were kept in a 37°C water bath for 60 h, equivalent to the time period of 3-months inter-oral use. MG deformation was analyzed by measuring designated points on the MG border using a profile projector (J-12, Nikon Inc., Tokyo, Japan) before and after the water immersion. A finite-element model was also created to examine the time course of stress accumulation during the sheet forming process using Finite Element software. Longitudinal deformation was smaller in the laminated MGs than in the single-layer MGs in the anterior area ( P  < 0.05). Finite element method (FEM) analysis also showed the largest stress accumulation in the anterior incisal area where deformations were mainly observed. Laminated double layer MGs have advantages over single-layer MGs in terms of longitudinal stability due to lower stress accumulation during the fabrication process.     

以改良TRAP法检测人膀胱肿瘤组织中端粒酶活性表达的临床意义

目的：探讨膀胱肿瘤及癌旁组织端粒酶活性表达及临床意义。方法：以改良TRAP法测定91例膀胱癌组织标本端粒酶活性表达。结果：83例膀胱移行细胞癌组织中78例检出端粒酶活性。阳性率为94％，其对应的癌旁组织也有14％的检出率，8例膀胱乳头状瘤组织中4例检出端粒酶活性，阳性率为50％，其对应的癌旁组织检出率为12％，端粒酶活性在不同临床病理类型的膀胱肿瘤及癌旁组织中表达无显差异（P＞0．05），结论：应用非放射性的银染方法对端粒酶的活性进行检测，图像清晰，简便，安全，易于临床推广。     

鹅去氧胆酸连接氨基酸的合成

胆石症是一种常见病,鹅去氧胆酸(CDCA)可用于胆固醇胆石症的治疗。它能改变胆汁组成,降低胆汁内胆固醇饱和度,增加胆固醇溶解性,使胆石逐渐溶解。但CDCA易被肠道内细菌7-脱羟酶作用生成石胆酸(LC),引起腹泄、腹部痉挛、高转     

医疗设备投资决策的敏感性分析研究

不恰当的医疗设备投资对医院及患者的利益均会造成损失，因此，在投资决策前进行严谨科学地可行性评估十分必要。通过对净现值的敏感性分析，医院的决策者可以了解各种不确定因素对投资方案经济效果的影响程度，以及投资方案对外部条件变化的承受能力，从而掌握风险条件下正确的决策原则和决策方法。