酪氨酸-铜体系电化学氧化行为的研究

在ｐＨ值３．９４的Ｂ－Ｒ缓冲溶液中,酪氨酸－铜络合物在玻碳电极出现氧化峰。用新极谱法测定,酪氨酸浓度在０．３μｇ／ｍｌ－３μｇ／ｍｌ范围内与氧化峰的２．５次微分值呈线性,检测下限０．２μｇ／ｍｌ。直接用于氨基酸药物样品的测定结果满意,并对酪氨酸－铜络合物的电化学氧化行为进行了研究。     

HPLC法检测红豆杉细胞培养物中的紫杉醇

在对紫杉醇和干扰紫杉醇测定的６种常见紫杉烷进行色谱化分离的基础上,建立了红豆杉细胞培养物中紫杉醇的高效相色谱检测方法。样品经提取后,在Ｋｒｏｍａｓｉｌ Ｃ１８柱上以乙腈：水为流动相进行梯度洗脱,于２２７ｎｍ处进行检测。紫杉醇在０．２μｇ／ｍｌ－２０μｇ／ｍｌ浓度范围内线性关系良好,经测定检测限为０．１μｇ／ｍｌ,检测精密度为３．４％,回收率为８８．４％。     

茶儿茶素氧化产物体外清除·OH自由基作用的研究

本文采用２－脱氧－Ｄ－核糖（ＤＲ）法产生．ＯＨ,测定了不同浓度的茶儿素氧化产物Ａ及Ｃ对．ＯＨ的清除作用。结果表明,在一定的浓度范围内,氧化产物Ａ及Ｃ均有很强的清除．ＯＨ的作用且最佳清除浓度为２００μｇ／ｍｌ。在茶多酚、氧化产物Ａ及Ｃ三种物质中,以产物Ｃ的清除作用最强,其ＩＣ５０值为７．３μｇ／ｍｌ,其次是Ａ,ＩＣ５０为１０．１μｇ／ｍｌ,最后是茶多酚,ＩＣ５０值为７０μｇ／ｍｌ。     

天竺葵花清除自由基作用的研究

用化学发光法研究了天竺葵花粗担液对超氧阴离子自由基（Ｏ２）＾＝和羟自由基（ＯＨ）的清除作用,用分光不镀法研究了它对１,１－二苯基－２－苦肼基自由基（ＤＰＰＨ０的清除作用。结果表明,天竺葵花具有很强的清除自由基活性。其粗提物清除Ｏ２＾－分别为３．５μｇ／ｍｌ（红花）,３．０μｇ／ｍｌ（粉花）,１．６μｇ／ｍｌ（浅粉花）,与茶多酚（ＩＣ５０＝１．１μｇ／ｍｌ）相近,清除ＯＨ的ＩＣ５０分别为５．７μｇ／     

喹诺酮类药物抗乙型肝炎病毒体外实验研究

本文以２．２．１５细胞株为模型,以ＨＢｓＡｇ、ＨＢｅＡｇ、ＨＢＶＤＮＡ、细胞存活率为观察指标,综合评价了喹诺酮类药物吡哌酸（ＰｉｐｅｍｉｄｉｃＡｃｉｄ）、氟哌酸（Ｎｏｒｆｌｏｘａｃｉｎ）、环丙氟哌酸（Ｃｉｐｒｏｆｌｏｓｘａｃｉｎ）、氟嗪酸（Ｏｆｌｏｘａｃｉｎ）体外抗ＨＢＶ效果。结果表明：吡哌酸、氟哌酸、环丙氟哌酸、氟嗪酸对ＨＢｓＡｇ、ＨＢｅＡｇ５０％抑制浓度（ＩＤ＿（５０））分别为１１μｇ／ｍｌ、６４μｇ／ｍｌ、９３μｇ／ｍｌ、１０５μｇ／ｍｌ和１９９μｇ／ｍｌ、１１１μｇ／ｍｌ、２４μｇ／ｍｌ、２１７μｇ／ｍｌ,细胞存活率为５０％时的药物浓度（ＣＤ＿（５０））分别为２１９μｇ／ｍｌ、９０μｇ／ｍｌ、１８１μｇ／ｍｌ、１６９μｇ／ｍｌ,在所选定的用药浓度范围内不同程度抑制培养上清液及细胞内ＨＢＶＤＮＡ及其复制中间体的产生。尤其对超螺旋结构ＤＮＡ（ｓｃＤＮＡ）有不完全抑制作用。     

乙型肝炎血源疫苗皮内接种4年效果观察

为了解乙型肝炎血源疫苗皮内接种的持久效果,选ＨＢｓＡｇ、抗－ＨＢｓ和抗－ＨＢｃ均（－）的９～１１岁儿童１０３名,随机分成４组,分别皮内接种１μｇ×４和３μｇ×４（均按０,１,２,５月程序）和肌肉接种１０μｇ×３和３０μｇ×３（各按０,１,２月程序）。首针后４８月时,１μｇ、３μｇ、１０μｇ和３０μｇ组抗－ＨＢｓ≥１０ｍＩＵ／ｍＩ者各为６９．２％,８０．０％、９２．３％和８１．８％;ＧＭＴ则为１４．５,７９．０,４４．８和７０．９ｍＩＵ／ｍｌ,３μｇ×４皮内免疫的近期和远期效果与肌肉组３０μｇ×３相似,宜于某些人群采用     

新型生物表面活性剂甘露糖赤藓糖醇脂（MEL）的分离与表面性质研究

本文通过对Ｃａｎｄｉｄａａｎｔａｒｃｔｉｃａ生产的生物表面活性剂甘露糖赤藓糖醇（ＭＥＬ）的分离条件的研究,得到了该生物表面活性剂分离的最佳条件：硅胶粒径２００目,洗脱剂分为氯信丙酮混合溶剂,配比分别是７：３（ＭＥＬ－Ａ）与６：４（ＭＥＬ－Ｂ）,洗脱速率为０．２５ｍｌ／ｍｉｎ,洗脱剂用量为４００ｍｌ／ｇＭＥＬ。对ＭＥＬ表面性质的研究发现其具有较好的表面活性,是一种良好的天然表面活性剂。     

酶联免疫分析法测定人α1型基因工程干扰素成品中的干扰素蛋白含量

建立了测定人α１型基因工程干扰素（ｒＩＦＮ－α）成品中干扰素蛋白含量的酶联免疫分析法（ＥＬＩＳＡ）,并用来测定了随机抽样的１０μｇ／支、２０μｇ／支、３０μｇ／支３种规格ｒＩＦＮ－α１成品中的干扰素蛋白含量。证明测定值与推算值一致,偏差小于１０％,而且蛋白含量与生物活性之间呈良好的相关性。本法敏感、特异、快速、简便、灵敏度可达到１ｎｇ／ｍｌ,检测人γ型基因工程干扰素的蛋白含量呈阴性,还能排除保护剂     

气相色谱法测定人白蛋白制品中辛酸钠含量

本文报导用气相色谱法测定人白蛋白制品中辛酸钠含量。样品用正庚酸作内标,经酸化、氯仿抽提、浓缩后,通过ＨＰ－ＩＮＮＯＷａｘ柱,以氢火焰检测器测定。本法色谱峰形好,平均回收率及变异系数分别为９８．５４％、１．３９％。测定线性范围在１０７μｇ／０．２５ｍｌ～７２０μｇ／０．２５ｍｌ。最小检测限为７．４１０μｇ。实验操作简便,样品及溶剂用量少,可作为人白蛋白制品中辛酸钠含量的检测方法。     

小鼠腺病毒单克隆抗体的研制及初步应用

应用杂交瘤技术获得４株分泌抗小鼠腺病毒（ＭｕｒｉｎｅＡｄｅｎｏｖｉｒｕｓＭＡｄ）单克隆抗体细胞株,并对其特性进行分析。经鉴定,它们所分泌的抗体类型均为ＩｇＭ,腹水效价为１０－３～１０－６。相对亲和力分别为０．１μｇ／ｍｌ（Ａ９）、０．６５μｇ／ｍｌ（Ｂｌ）、１２．５μｇ／ｍｌ（Ｇ４）和２３μｇ／ｍｌ（Ｄ４）。与其他１０种鼠源性病毒均无交叉反应,表明ＭｃＡｂ具有良好的特异性。单抗标记ＦＩＴＣ后用于人用鼠源性单抗制品及各种传代细胞和原代细胞中ＭＡｄ检测,获得良好的实验结果。     

光生态膜对黄瓜生态的影响

通过叶片的反射光谱测量来研究黄瓜的光合作用之作用光谱,采用在高分子树脂中分散进荧光助剂、着色剂来模拟栽培作物的作用光谱。用这种光生态膜苫盖日光温室进行黄瓜生产,产量提高了２１．４％。     

莴苣的光生态研究

通过叶片的反射光谱测量来研究莴苣的光生态,采用在高分子树脂中分散进荧光助剂、着色剂来模拟栽培作物的光合作用之作用光谱。用这种光生态膜苫盖温室大棚进行蔬菜生产,产量提高了４４．６％ 。     

Darkfield Adapter for Whole Slide Imaging: Adapting a Darkfield Internal Reflection Illumination System to Extend WSI Applications

We present a new method for whole slide darkfield imaging. Whole Slide Imaging (WSI), also sometimes called virtual slide or virtual microscopy technology, produces images that simultaneously provide high resolution and a wide field of observation that can encompass the entire section, extending far beyond any single field of view. For example, a brain slice can be imaged so that both overall morphology and individual neuronal detail can be seen. We extended the capabilities of traditional whole slide systems and developed a prototype system for darkfield internal reflection illumination (DIRI). Our darkfield system uses an ultra-thin light-emitting diode (LED) light source to illuminate slide specimens from the edge of the slide. We used a new type of side illumination, a variation on the internal reflection method, to illuminate the specimen and create a darkfield image. This system has four main advantages over traditional darkfield: (1) no oil condenser is required for high resolution imaging (2) there is less scatter from dust and dirt on the slide specimen (3) there is less halo, providing a more natural darkfield contrast image, and (4) the motorized system produces darkfield, brightfield and fluorescence images. The WSI method sometimes allows us to image using fewer stains. For instance, diaminobenzidine (DAB) and fluorescent staining are helpful tools for observing protein localization and volume in tissues. However, these methods usually require counter-staining in order to visualize tissue structure, limiting the accuracy of localization of labeled cells within the complex multiple regions of typical neurohistological preparations. Darkfield imaging works on the basis of light scattering from refractive index mismatches in the sample. It is a label-free method of producing contrast in a sample. We propose that adapting darkfield imaging to WSI is very useful, particularly when researchers require additional structural information without the use of further staining.     

玉米和花生根际生物的原位观察初探*

利用改进根箱法对玉米和花生根际生物进行了原位采样和观察。采用载玻片贴片方法直接采集到作物根系分泌物中的生物,并用荧光显微镜进行观察。花生根系分泌物中分布有微生物,但是根系表面未发现生物;玉米根系分泌物中分布有线虫和生物体,根系表面分布有生物体,其形态与根系分泌物中生物体形态相似。表明此方法是一种原位研究根际生物的较为有效的方法。     

Kinetics of the formation and dissociation of actin filament branches mediated by Arp2/3 complex

The actin filament network at the leading edge of motile cells relies on localized branching by Arp2/3 complex from "mother" filaments growing near the plasma membrane. The nucleotide bound to the mother filaments (ATP, ADP and phosphate, or ADP) may influence the branch dynamics. To determine the effect of the nucleotide bound to the subunits of the mother filament on the formation and stability of branches, we compared the time courses of actin polymerization in bulk samples measured using the fluorescence of pyrene actin with observations of single filaments by total internal reflection fluorescence microscopy. Although the branch nucleation rate in bulk samples was nearly the same regardless of the nucleotide on the mother filaments, we observed fewer branches by microscopy on ADP-bound filaments than on ADP-P(i)-bound filaments. Observation of branches in the microscope depends on their binding to the slide. Since the probability that a branch binds to the slide is directly related to its lifetime, we used counts of branches to infer their rates of dissociation from mother filaments. We conclude that the nucleotide on the mother filament does not affect the initial branching event but that branches are an order of magnitude more stable on the sides of new ATP- or ADP-P(i) filaments than on ADP-actin filaments.     

土壤镉污染对水稻叶片光谱反射特性的影响

水稻移栽于添加不同量镉(50、100、200和400 ppm)的土壤上,叶片反射光谱特性发生变化:可见光区反射率增加,其中550—680nm波段反射率的增加更突出;反射光谱的一次微分图和二次微分图上叶绿素吸收边缘明显蓝移。这些变化以分蘖期最为显著。镉害水稻可见光区反射特性的变化与叶片中叶绿素含量的降低相一致。初步确定几个波段可用于区分镉毒害的和正常的水稻的光谱反射特性。     

PHOTOGRAPHIC VISUALIZATION OF FLORAL COLORS AS PERCEIVED BY HONEYBEE POLLINATORS

An inexpensive photographic technique for visualizing the ultraviolet and visible wavelengths perceived by honeybees is described. Using a standard daylight-balanced color slide film and illumination from blacklight and filtered daylight fluorescent lamps, a recording balance was achieved which approximates the spectral sensitivity of the honeybee eye. The technique was used to illustrate floral features among Rudbeckia species and among color morphs of Phlox. The Rudbeckia have inflorescences that are similar in visible coloration but distinctive in ultraviolet patterning and Phlox color morphs are distinctive in visible coloration but similar in ultraviolet patterning. The efficacy of the technique was judged from comparison with in vivo reflectance spectra of the floral subjects. Generally, photographic visualizations of entomophilous flowering plants portray only the ultraviolet or the visible components of floral coloration. This technique emphasizes the importance of considering the entire spectrum of floral colors relevant to most insect pollinators.     

A plasma-polymerized film for capacitance immunosensing

A capacitance immunosensor based on a plasma-polymerized ethylenediamine film (PPEF) has been developed. The resulting PPEF is studied with scanning electrode micrograph (SEM), IR reflection spectrum and cyclic voltammetry. SEM and IR reflection spectrum showed that the plasma-polymerized film (PPF) formed on the gold electrode surface is quite homogeneous, flat, nonporous and contains plenty of free-reacted -NH2. Moreover, cyclic voltammetry showed that the hexacyanoferrate redox reactions were blocked well by the formed PPF, that is to say, the formed PPF has excellent insulating characteristics. To investigate its applicability for capacitive immunosensing, goat-anti-human IgG antibody (IgGAb) was coupled to the PPF-coated gold electrode surface via glutaraldehyde (GA) to form an immunoglobulin G (IgG) probe. Alternating current (ac) impedance and capacitance measurement were used in the immunoassay. The experiment results show that the PPEF is applicable to form insulating layer of capacitive immunosensors.     

Synthesis of 6-thio pseudo glycolipids and their orientation on a gold slide studied by IRRAS

We have synthesized four 6-thio pseudo glycolipid analogues and assessed how two of them self-assembled on a gold surface. These structures were designed as candidate tethers molecules to anchor bilayer lipid membranes on gold. 6-Deoxy-6-thiogalactose was chosen to anchor the macromolecule to the gold and define an aqueous zone at the gold surface. A long alkane chain (C-12 or C-18) linked to the anomeric position of the sugar residue was chosen to anchor a bilayer lipid membrane. The linkage between the carbohydrate and the hydrophobic chains is either a glycosidic bond or a 1,4-disubstituted triazole formed by copper(I)-catalysed alkyne-azide cycloaddition (CuAAC) of the propargyl glycoside with azido-dodecane and azido-octadecane. We are expecting that the hydrocarbon chains will orient themselves perpendicular to the gold surface and be incorporated into the first leaflet of the bilayer membrane. We have studied self assembled monolayers of the C-12 aglycone analogues on gold using infrared reflection absorption spectroscopy (IRRAS). We compared the results given by the IRRAS experiments to the IR spectra recorded by attenuated total reflection (ATR) spectroscopy on films of the randomly oriented analogues. Our results demonstrate that the C-12 analogues did bind to gold and did orient themselves perpendicular to the gold slide.     

珠江口水体的光学特征及分析

通过2003年1月份对珠江口水体中的光谱分布,衰减系数,光反射率以及浮游植物对光吸收的研究结果显示:红光、蓝光衰减较快,绿光衰减较小,越向水体下层,绿光的相对含量越大,这主要是由于浮游植物在蓝光和红光波段处有吸收峰以及非藻颗粒对蓝紫光吸收较多的缘故;从总体来讲,绿光的辐亮度漫反射率(Lu/Ed)较蓝光和红光大:在上层水体中有一个反射强度较大的区域,可能是由于浮游植物在这一层的分布较多。