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1.
采用免疫化学方法,以胸苷激酶(TK)抗体检测了5种培养的细胞(4种癌细胞和1种正常细胞)及12种人类癌组织切片.结果表明,正常细胞呈阴性结果,4种癌细胞及12种癌组织均呈阳性结果.提示此种方法在癌症的临床诊断方面可能有意义.  相似文献   
2.
When rhodamine-based fluorescent probe dyes are used to track target molecules they always perturb the behavior of target molecules because of steric hindrance effect. In order to minimize potential steric problems, a kind of rhodamine-based fluorescent probe dye with spacer linker arm was designed and synthesized and its application in immunofluorescence histochemistry was investigated.  相似文献   
3.
The analysis of vitamin D status, with special emphasis on 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D, is gaining interest in clinical studies due to the classical and non-classical effects attributed to this prohormone. In this research, the influence of the two steps preceding determination (viz. sample collection and preparation) on the quantitative analysis of vitamin D and its more important metabolites has been studied. Two preparation approaches, deproteination and solid-phase extraction (SPE), have been evaluated in terms of sensitivity to delimit their application, thus establishing that detection of 1,25-dihydroxyvitamin D cannot be addressed by protein precipitation. Concerning sample collection, serum and plasma reported high accuracy (above 83.3%) for vitamin D and metabolites, while precision, expressed as relative standard deviation, was below 12.9% for all analytes in both samples. Statistical analysis revealed that serum and plasma provided similar physiological levels for vitamin D3, 24,25-dihydroxyvitamin D3 and 25-hydroxyvitamin D3, while significantly different levels were obtained for 1,25-dihydroxyvitamin D3, always higher in plasma than in serum. Sample collection and treatment have proved to be significant in the analysis of vitamin D and its relevant metabolites.  相似文献   
4.
微黄镰玉螺消化系统的组织学与组织化学研究   总被引:1,自引:0,他引:1       下载免费PDF全文
微黄镰玉螺的消化系统由消化道和消化腺两部分组成;消化道包括口、食道、胃、肠及直肠;消化腺包括食道腺,肝胰腺和肛门腺,无唾液腺,在光学显微镜下,消化道由粘膜层,粘膜下层,肌层和外膜4层结构构成,描述了消化道及消化腺的结构特征,并利用组织学方法测定了消化腺细胞中的蛋白质和酶类,对各消化腺的功能作了初步分析。  相似文献   
5.
Due to their benthic filter-feeding habits and high bioaccumulation potential of metals and organic compounds, bivalve molluscs have been widely used in studies in the field and laboratory to assess the toxic effects of several compounds discharged in rivers, oceans and estuaries. However, most ecotoxicological studies use invasive exotic species, while the response of native species is poorly known. The Brazilian endemic species Diplodon expansus occurs in rivers near areas of intense agricultural activity, and atrazine is currently one of the main residues of pesticides found in water bodies of the Brazilian territory. This study was aimed at examining the toxicity of different atrazine concentrations to a Brazilian native mollusc by analysing the histology, histochemistry and ultrastructure of its gill filaments. The cells that comprise the frontal and intermediary regions of gill filaments were the most affected by the herbicide and responses associated with damage and protection were observed. The response of tissues and cells were dose-dependent. Higher concentrations of herbicide caused more severe alterations in large areas of the gills. The persistence of the alterations observed might result in severe functional problems in the gills of these animals, negatively affecting their performance and health.  相似文献   
6.
Immuno‐oncology (IO) is an emerging option to treat cancer malignancies. In the last two years, IO has accounted for more than 90% of the new active drugs in various therapeutic indications of oncology drug development. Bioanalytical methods used for the quantitation of various IO small molecule drugs have been summarized in this review. The most commonly used are HPLC and LC–MS/MS methods. Determination of IO drugs from biological matrices involves drug extraction from the biological matrix, which is mostly achieved by simple protein precipitation, liquid–liquid extraction and solid‐phase extraction. Subsequently, quantitation is usually achieved by LC–MS/MS, but HPLC–UV has also been employed. The bioanalytical methods reported for each drug are briefly discussed and tabulated for easy access. Our review indicates that LC–MS/MS is a versatile and reliable tool for the sensitive, rapid and robust quantitation of IO drugs.  相似文献   
7.
In recent years, original hybrid assemblies composed of a particle core surrounded by a lipid shell emerged as promising entities for various biotechnological applications. Their broadened bio-potentialities, ranging from model membrane systems or biomolecule screening supports, to substance delivery reservoirs or therapeutic vectors, are furthered by their versatility of composition due to the possible wide variation in the particle nature and size, as well as in the lipid formulation. The synthesis, the characteristics, and the uses of these Lipid/Particle assemblies encountered in the literature so far are reviewed, and classified according to the spherical core size in order to highlight general trends. Moreover, several criteria are particularly discussed: i) the interactions involved between the particles and the lipids, and implicitly the assembly elaboration mechanism, ii) the most suited techniques for an accurate characterization of the entities from structural and physicochemical points of view, and iii) the remarkable properties of the solid-supported lipid membrane obtained.  相似文献   
8.
A novel automated flow immunoassay system is developed for the detection of wheat protein as a food allergen. A polyclonal immunoglobulin G (IgG) antibody was isolated from serum of a rat with a wheat allergy, then reductively treated using dithiothreitol and covalently coupled to alkaline phosphatase. This conjugate was used in a non-competitive binding assay. The automated system was equipped with an immunoreaction column, an anion-exchange column, a luminescent reaction column and a photodetector. Antibody–antigen complexes were separated from their free conjugate on the basis of a difference in isoelectric point (pI) by an anion-exchange column. This simple technique permits the assay of wheat-protein allergen in 25 min with a reliable detection limit of 5 μg/ml. The anion-exchange column was regenerated by occasional elution with N-methylpiperazine buffer (pH 5.0) containing 0.5 M NaCl, to remove free conjugate. Free conjugate recovered in this manner could be reused up to four times without significant decrease in sensitivity of the immunoassay.  相似文献   
9.
通过免疫印迹法研究了抗大肠杆菌RNA聚合酶σ70因子的抗体对产气杆菌、金黄色葡萄球菌和不同生长阶段的天蓝色链霉菌细胞内蛋白质的免疫识别作用.结果表明,抗大肠杆菌RNA聚合酶σ70因子抗体能特异性地识别上述微生物细胞内的一些蛋白质.对这些蛋白质的属性作了讨论,认为它们是RNA聚合酶的转录因子.本研究还发现,抗大肠杆菌RNA聚合酶σ70因子抗体识别的产气杆菌细胞内的蛋白质,在数量和种类上几乎完全与大肠杆菌相同.  相似文献   
10.
探讨错配修复基因MLH1、MSH2在散发性左、右半结肠患者中的表达差异, 并分析这种差异与结直肠癌临床病理特征的相关性. 收集2015年12月至2018年12月期间, 在宁波市第一医院就诊的133例结直肠癌患者的病例资料, 分析左、右半结肠癌中MLH1、MSH2基因的表达差异, 以及这种差异与结直肠癌临床病理特征的相关性. 结果表明, 在结直肠癌病例中, MLH1、MSH2的表达缺失率与肿瘤的发病部位和分化程度有关(P<0.05), 右半结肠癌的病例与总体样本表现更相近. 在散发性结直肠癌中, MLH1、MSH2的表达缺失率方面, 右半结肠癌高于左半结肠. 在右半结肠癌病例中, MLH1、MSH2的表达缺失患者相对发病年龄早, 分化程度低, 不容易发生神经浸润; 而在左半结肠癌MLH1、MSH2的表达缺失病例中, 无明显相关表现.  相似文献   
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