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建立一种靶点蛋白质快速定量检测方法。在原有侧向流动免疫层析技术的基础上,通过优化层析材料和纳米微球的均一性、改进检测区的检测方法,经逐点扫描技术,建立标准浓度曲线,以达到对临床靶点蛋白质的定量检测。以乳腺癌组织中的Her2表达为例,通过对已知浓度样品的检测,验证本技术方法的准确度大于96%。另外,以蛋白质免疫印迹作为组织中特定蛋白质检测金标准,分析临床肿瘤组织中Her2蛋白的含量,其准确率也达到95.5%,而免疫组织化学方法检测准确率仅为69.58%。新型免疫层析法检测结果与靶向治疗患者的愈后密切相关(P<0.01)。改进后的新型免疫层析方法能够准确地对临床靶点蛋白质进行定量检测,而且结合侧向流动技术的简单、快速和易用性,这种新型检测方法可以广泛应用于临床组织标本、血液标本和体液标本中靶点蛋白质的临场定量检测,在一定程度上可以替代免疫组化技术。 相似文献
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Aluminium is the most abundant metal in the Earth's crust and yet, paradoxically, it has no known biological function. Aluminium is biochemically reactive, it is simply that it is not required for any essential process in extant biota. There is evidence neither of element-specific nor evolutionarily conserved aluminium biochemistry. This means that there are no ligands or chaperones which are specific to its transport, there are no transporters or channels to selectively facilitate its passage across membranes, there are no intracellular storage proteins to aid its cellular homeostasis and there are no pathways which evolved to enable the metabolism and excretion of aluminium. Of course, aluminium is found in every compartment of every cell of every organism, from virus through to Man. Herein we have investigated each of the ‘silent’ pathways and metabolic events which together constitute a form of aluminium homeostasis in biota, identifying and evaluating as far as is possible what is known and, equally importantly, what is unknown about its uptake, transport, storage and excretion. 相似文献
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Abstract Two new species of water mites, Pionopsis (s.s.)longicosta sp. nov. and Pionopsis (s.s.) zhaoi sp. nov. are described in the present paper. This is the first record of the genus of the subfamily Tiphyinae in the family Pionidae from China. 相似文献
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Intracellular Development of Enterocytozoon, A Unique Microsporidian Found in the Intestine of AIDS Patients 总被引:2,自引:0,他引:2
Enterocytozoon was 1st described in 1985, in an AIDS patient with intestinal malabsorption and diarrhea. Since then, additional cases of infection with this organism have been observed, but only in individuals with AIDS and malabsorption. Intestinal tissue biopsies were obtained from a 45-year-old man prior to AIDS diagnosis, again nine months later and then at autopsy two months later. When the biopsies were examined electron microscopically, both sets contained the microsporidian parasite. However, the 2nd intestinal biopsy, when wasting was much more severe, contained infection in almost every small intestinal enterocyte examined. The parasite was actively developing, allowing us to detail its life cycle. The parasite is apansporoblastic, polysporous and has characteristics not previously reported in the Microsporida: (1) an electron lucent inclusion not usually seen in Microsporida is prominent and always present; (2) extremely elongated sausage-shaped nuclei occur in the proliferative phase of parasite development; (3) the polar tube development uniquely involves the production of electron dense discs, yet results in the formation of a typical spore; and (4) polar tube development occurs prior to the final division of the multi-nucleate sporont. On the basis of these characteristics, we are placing this genus in a new family, Enterocytozoonidae, n. fam. 相似文献
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K. Yoshikawa 《Journal of biological physics》2002,28(4):701-712
The mechanism of the self-regulation of gene expression in living cells is generally explained by considering complicated networks of key-lock relationships, and in fact there is a large body of evidence on a hugenumber of key-lock relationships. However, in the present article we stress that with the network hypothesis alone it is impossible to fully explain the mechanism of self-regulation in life. Recently, it has been established that individual giant DNA molecules, larger than several tens of kilo base pairs, undergo a large discrete transition in their higher-order structure. It has become clear that nonspecific weak interactions with various chemicals, suchas polyamines, small salts, ATP and RNA, cause on/off switching in the higher-order structure of DNA. Thus, the field parameters of the cellular environment should play important roles in the mechanism of self-regulation, in addition to networks of key and locks. This conformational transition induced by field parameters may be related to rigid on/off regulation, whereas key-lock relationships may be involved in a more flexible control of gene expression. 相似文献
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DNA replication is a fundamental process of the cell that ensures accurate duplication of the genetic information and subsequent transfer to daughter cells. Various pertubations, originating from endogenous or exogenous sources, can interfere with proper progression and completion of the replication process, thus threatening genome integrity. Coordinated regulation of replication and the DNA damage response is therefore fundamental to counteract these challenges and ensure accurate synthesis of the genetic material under conditions of replication stress. In this review, we summarize the main sources of replication stress and the DNA damage signaling pathways that are activated in order to preserve genome integrity during DNA replication. We also discuss the association of replication stress and DNA damage in human disease and future perspectives in the field. 相似文献