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1.
The synthesis of acute-phase protein serum amyloid A (SAA) is largely regulated by inflammation- associated cytokines and a high concentration of circulating SAA may represent an ideal marker for acute and chronic inflammatory diseases. However, SAA is also synthesized in extrahepatic tissues, e.g. human carcinoma metastases and cancer cell lines. An increasing body of in vitro data supports the concept of involvement of SAA in carcinogenesis and neoplastic diseases. Accumulating evidence suggests that SAA might be included in a group of biomarkers to detect a pattern of physiological events that reflect the growth of malignancy and host response. This review is meant to provide a broad overview of the many ways that SAA could contribute to tumour development, and accelerate tumour progression and metastasis, and to gain a better understanding of this acute-phase reactant as a possible link between chronic inflammation and neoplasia. Received 11 June 2008; received after revision 10 July 2008; accepted 28 July 2008  相似文献   

2.
Summary In this report we present an analysis by atomic absorption spectrometry of some of the transition metals Fe, Zn, Cu, Mn, Co, and Ni in tissues and nuclear fractions in an experimental tumour system.Acknowledgments. The atomic absorption spectroscopic analysis was done at the Health Physics Division, Bhabha Atomic Research Centre, Bombay. The author are indebted to Dr S.D. Soman, Director, Health Physics Division for providing facilities for the said analysis.  相似文献   

3.
人类定义的改变将南方古猿纳入人类的范围,延长了人类历史的记录。70年代延长到300多万年,90年代延长到400多万年。人造石器的历史已达250万年。人类最可能诞生于非洲,大约在200万年前走出非洲。直立人近年最重要的发现还有非洲纳里奥科托姆160万年前的骨架和西班牙78万年前的人骨。人类到达澳洲在6万年前。早期人类进化模式呈树丛状;晚期的模式较可能呈河网状。最近在中国人类进化研究的基础上提出了新的假说:“连续进化附带杂交”。这个假说支持现代人起源的“多地区进化说”,并受到旧石器考古研究的支持,而与“现代人出自非洲说”(夏娃说或替代说)相矛矛盾。近年有人根据对现生中国人28个群体的遗传学研究推测“夏娃”的后代在6万年前到达华南取代原住民,以后再到华北。将非洲和欧亚头骨,西亚和中国旧石器进行对比研究的结果指示“替代  相似文献   

4.
Tenascin-C is an extracellular matrix glycoprotein that is specifically and transiently expressed upon tissue injury. Upon tissue damage, tenascin-C plays a multitude of different roles that mediate both inflammatory and fibrotic processes to enable effective tissue repair. In the last decade, emerging evidence has demonstrated a vital role for tenascin-C in cardiac and arterial injury, tumor angiogenesis and metastasis, as well as in modulating stem cell behavior. Here we highlight the molecular mechanisms by which tenascin-C mediates these effects and discuss the implications of mis-regulated tenascin-C expression in driving disease pathology.  相似文献   

5.
Skin is an organ that is susceptible to damage by external injury, chronic inflammation, and autoimmunity. Tissue damage causes alterations in both the configuration and type of cells in lesional skin. This phenomenon, called tissue remodeling, is a universal biological response elicited by programmed cell death, inflammation, immune disorders, and tumorigenic, tumor proliferative, and cytoreductive activity. In this process, changes in the components of the extracellular matrix are required to provide an environment that facilitates tissue remodeling. Among these extracellular matrix components, periostin, a glycoprotein that is predominantly secreted from dermal fibroblasts, has attracted attention. Periostin localizes in the papillary dermis of normal skin, and is aberrantly expressed in the dermis of lesional skin in atopic dermatitis, scar, systemic/limited scleroderma, melanoma, cutaneous T cell lymphoma, and skin damage caused by allergic/autoimmune responses. Periostin induces processes that result in the development of dermal fibrosis, and activate or protract the immune response. The aim of this review was to summarize recent knowledge of the role of periostin in the pathogenesis of dermatoses, and to explore whether periostin is a potential therapeutic target for skin diseases.  相似文献   

6.
Evolution of bacterial pathogenesis   总被引:6,自引:0,他引:6  
The evolution of bacteria is associated with continuous generation of novel genetic variants. The major driving forces in this process are point mutations, genetic rearrangements, and horizontal gene transfer. A large number of human and animal bacterial pathogens have evolved the capacity to produce virulence factors that are directly involved in infection and disease. Additionally, many bacteria express resistance traits against antibiotics. Both virulence factors and resistance determinants are subject to intrastrain genetic and phenotypic variation. They are often encoded on unstable DNA regions. Thus, they can be readily transferred to bacteria of the same species or even to non-related prokaryotes. This review article focuses on the main mechanisms of bacterial microevolution responsible for the rapid emergence of variants with novel virulence and resistance properties. In addition, processes of macroevolution are described with special emphasis on gene transfer and fixation of adaptive mutations in the genome of pathogens.  相似文献   

7.
Summary Experimental proof that tumour vessels are permeable to humoral agents but impermeable to cellular elements viz. leucocytes. The cause of this impermeability is believed to be the deposition of immunosuppressive alpha globulin on the walls of tumour vessels. This concept is of relevance in organ transplantation and cancer immunotherapy.  相似文献   

8.
S S Ranade  S Shah  P Haria 《Experientia》1979,35(4):460-461
In this report we present an analysis by atomic absorption spectrometry of some of the transition metals Fe, Zn, Cu, Mn, Co, and Ni in tissues and nuclear fractions in an experimental tumour system.  相似文献   

9.
No Abstract. .Received 4 March 2005; received after revision 7 April 2005; accepted 26 April 2005  相似文献   

10.
生物转化具有底物选择性、立构选择性、化学选择性、对映选择性等一般化学反应中不具备的优点,在精细化工中占有很大的优势,其中Baeyer-Villiger氧化反应在生物转化中占有很重要的地位,产生的许多中间体或产物可以被用来生产多种化学产品和药物,在工业生物催化中有很好的应用前景。本文主要对生物转化中的Baeyer-Villiger氧化反应在利用酶或细胞作为催化剂时存在的问题和解决方法以及基因技术的运用近况进行了综述。  相似文献   

11.
12.
Riassunto Dopo una breve introduzione storica, viene dato un quadro delle attuali conoscenze sulla chimica degli ossidi di nitrili con particolare riguardo ai suoi più recenti sviluppi. L'applicazione di metodi già noti e l'introduzione di nuovi metodi di preparazione hanno portato alla cinquantina il numero dei nitrilossidi isolati, oltre a quelli numerosi preparati in situ e utilizzati in reazioni di addizione senza isolarli. Vengono esaminate le reazioni di dimerizzazione e polimerizzazione, le numerose reazioni di addizione nucleofila che mettono in evidenza lo spiccato carattere elettrofilo dei nitrilossidi e, in particolare le addizioni sopra i legami etilenici e acetilenici che portano a isossazoline e isossazoli. Nuove acquisizioni sperimentali, come l'isolamento in rese sostanziali e talvolta preponderanti di ossime acetileniche accanto agli isossazoli, rimettono sul tappeto la questione della via battuta da quest'ultima reazione, suggerendo come possibile alternativa al meccanismo generalmente ammesso di cicloaddizione 1,3-dipolare concertata quello che passa attraverso uno «zwitterione» intermedio, dal quale tanto l'isossazolo che l'ossima possono pren'dere origine. Viene illustrate l'effetto catalitico del BF3 su alcune reazioni di addizione dei nitrilossidi, che consente l'ampliamento del campo di applicazione di queste reazioni. Vengono infine riportati i primi risultati dello studio della reattività dei nitrilossidi verso i radicali liberi al carbonio, studio che appare suscettibile di interessanti sviluppi.

12. Paul-Karrer-Vorlesung in der Aula der Universität Zürich am 24. Juni 1970.  相似文献   

13.
Eosinophils are traditionally thought to form part of the innate immune response against parasitic helminths acting through the release of cytotoxic granule proteins. However, they are also a central feature in asthma. From their development in the bone marrow to their recruitment to the lung via chemokines and cytokines, they form an important component of the inflammatory milieu observed in the asthmatic lung following allergen challenge. A wealth of studies has been performed in both patients with asthma and in mouse models of allergic pulmonary inflammation to delineate the role of eosinophils in the allergic response. Although the long-standing association between eosinophils and the induction of airway hyper-responsiveness remains controversial, recent studies have shown that eosinophils may also promote airway remodelling. In addition, emerging evidence suggests that the eosinophil may also serve to modulate the immune response. Here we review the highly co-ordinated nature of eosinophil development and trafficking and the evolution of the eosinophil as a multi-factoral leukocyte with diverse functions in asthma. Received 6 December 2006; received after revision 11 January 2007; accepted 15 February 2007  相似文献   

14.
Short sequence repeats in microbial pathogenesis and evolution   总被引:10,自引:0,他引:10  
Repetitive DNA is ubiquitous in microbial genomes. Different classes of short sequence repeats (SSRs) have been identified and demonstrated to be generally heterogeneous in a locus-dependent manner, reflected in variation in the number of repeat units present at a given genomic site or by sequence heterogeneity among individual units. Both types of variability can be used to assess intra-species genetic diversity. Repeat variability often affects the coding potential of the region in which the repetitive element is located. This implies that determination of the primary structure of variable numbers of tandem repeats can be used for epidemiological identification purposes, and also for the analysis of gene function. Precise assessment of SSR structure can also generate insight into the regulation of gene expression. Together, DNA repeat analysis in microbial species provides information on both functional and evolutionary aspects of genetic diversity among microbial isolates.  相似文献   

15.
Cardiac fibrosis is characterized by net accumulation of extracellular matrix proteins in the cardiac interstitium, and contributes to both systolic and diastolic dysfunction in many cardiac pathophysiologic conditions. This review discusses the cellular effectors and molecular pathways implicated in the pathogenesis of cardiac fibrosis. Although activated myofibroblasts are the main effector cells in the fibrotic heart, monocytes/macrophages, lymphocytes, mast cells, vascular cells and cardiomyocytes may also contribute to the fibrotic response by secreting key fibrogenic mediators. Inflammatory cytokines and chemokines, reactive oxygen species, mast cell-derived proteases, endothelin-1, the renin/angiotensin/aldosterone system, matricellular proteins, and growth factors (such as TGF-β and PDGF) are some of the best-studied mediators implicated in cardiac fibrosis. Both experimental and clinical evidence suggests that cardiac fibrotic alterations may be reversible. Understanding the mechanisms responsible for initiation, progression, and resolution of cardiac fibrosis is crucial to design anti-fibrotic treatment strategies for patients with heart disease.  相似文献   

16.
M C Horzinek 《Experientia》1987,43(11-12):1193-1196
Although a very wide range of viral diseases exists in vertebrates, certain generalizations can be made regarding pathogenetic pathways on the molecular level. The presentation will focus on interactions of virions and their components with target cells. Using coronaviruses as examples the changes in virulence have been traced back to single mutational events; recombination, however, is likely to be an alternative mechanism by which virus-host interactions (e.g. the cell-, organ- or animal species-spectrum) can dramatically change. Receptor molecules are essential for the early interactions during infection and some of these have been identified. Events in the target cell and the host organism are discussed, and wherever possible, aspects of virus evolution and cooperation between infectious agents are highlighted.  相似文献   

17.
Summary The application of banding techniques on cytological smears from pleural effusion in a case of histiocytic sarcoma has provided direct evidence for correspondence between nuclear projections in tumor cells and extra large chromosome markers observed in the neoplastic karyotype obtained by direct preparations.  相似文献   

18.
19.
红外物理与技术发展   总被引:6,自引:0,他引:6  
经过长期探索,人们掌握了红外辐射的基本规律,不断研制出新型,优质红外探测器件,发展了红外光谱和红外成像等重要技术。并使之在当代许多领域,尤其在遥感,军事及其它高科技领域占据突出地位。  相似文献   

20.
植物形态生长对策研究进展   总被引:7,自引:0,他引:7  
植物在其生长发育的各个阶段的生长行为及生活史策略皆与植物的形态可塑性有很大关系,可在一定程度上决定植物物种在生境中的分布格局及种群行为.植物生活史对策是植物物种维持生长和繁殖的资源最佳分配方式,物种的适应性是物种在进化过程中累积起来的,在形态上有很明显的表现,植物采取不同的形态生长策略就是为了使物种在某些阶段达到最大的适合度.已有的植物形态生长对策研究主要集中在植物繁殖体形态、幼苗形态策略、生长可塑性以及繁殖策略等方面,植物各阶段形态生长策略的权衡以及与植物在群落中的分布关系被认为是今后该方面研究的重要方面.  相似文献   

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