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101.
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103.
The Dama de Elche (4th–5th century B.C.), an emblematic piece of the ancient Iberian culture, was first sculpted in fossiliferous limestone of Tertiary
Age. In this first systematic study, two classic pigments have been identified: Egyptian blue, prepared with a potassium flux,
and natural vermilion applied over a preparation layer of gypsum, mixed with calcium carbonate, that migrated and recrystallized
on the polychrome surface of the bust, process favoured by the change suffered after its disinterment. No anachronisms have
been found on the identified polychromy, the existing coating surface nor any other element that might suggest it to be a
modern forgery.
Editorial note The “Eduardo Torroja” Institute (CSIC) is a RILEM Titular Member. Dra. M.P. de Luxán participates in RILEM TCs CUA ‘Concrete use of additions’ and RHM, ‘Repair mortars for historic buildings’. Dr. F. Dorrego also participates in RILEM TC RHM. 相似文献
Résumé La Dama de Eleche, sculpture emblématique de la culture ibère, fut taillée en pierre calcaire avec des fossiles de l'ère tertiaire. Dans cette première investigation systématique, on a identifié deux pigments classiques: le bleu égyptien, préparé avec un fondant potassique, et le vermillon naturel, appliqués sur une couche de préparation en platre, mélangé avec de la chaux, qui a migré et a recristallisé sur la surface polychrome du buste. Ce procédé a été aidé pour les changements subis après son déterrement. On n'a pas trouvé d'anachronisme en ce qui concerne les pigments et la couche de préparation. Aucun élément ne permet, de déduire que la sculpture puisse être un faux moderne.
Editorial note The “Eduardo Torroja” Institute (CSIC) is a RILEM Titular Member. Dra. M.P. de Luxán participates in RILEM TCs CUA ‘Concrete use of additions’ and RHM, ‘Repair mortars for historic buildings’. Dr. F. Dorrego also participates in RILEM TC RHM. 相似文献
104.
105.
Experimental evidence suggests a pathogenetic role for lipids in focal glomerulosclerosis (FGS) analogous to atherosclerosis. As foam cells (FC) are an important factor in atherosclerosis, a retrospective comparative study was done to evaluate the significance of intraglomerular FC in human FGS. Glomerular FC infiltration was evaluated in 115 biopsies of FGS, 120 biopsies of membranous glomerulonephritis (MGN) and 50 biopsies of minimal-change disease (MCD). Selected clinical and laboratory data collected at about the time of biopsy were reviewed. The proportion of biopsies showing glomerular FC was much higher in FGS (70%) than in either MGN (12%) or MCD (0%) p less than 0.001. The mean percent (+/- SD) of glomeruli with FC per biopsy was significantly greater in FGS (7.9 +/- 9.9) than in MGN (2.0 +/- 7.8; p less than 0.0001). Of the 14 MGN biopsies with FC, 13 showed superimposed FGS. Mean serum total cholesterol and triglyceride were not significantly higher in FGS than in either MGN or MCD. The results demonstrate a close association of glomerular FC infiltration with FGS. 相似文献
106.
HJ Schmitz A Hagenmaier HP Hagenmaier KW Bock D Schrenk 《Canadian Metallurgical Quarterly》1995,99(1-2):47-54
Among the polychlorinated biphenyls (PCBs), a family of widespread environmental pollutants, the most toxic non-ortho-substituted coplanar (non-ortho coplanar) congeners are thought to act as strong dioxin (aryl hydrocarbon) receptor agonists leading to adverse effects, such as body weight loss, immunosuppression, thymic atrophy, hepatotoxicity, tumor promotion, and disturbances of steroid hormone action. Since PCBs are present in environmental and tissue samples as complex mixtures, we investigated the possible interaction of non-ortho coplanar congeners with other major PCBs, which are less active or inactive as dioxin receptor agonists. As a parameter for dioxin receptor activation, induction of CYP1A-catalyzed 7-ethoxyresorufin O-deethylase (EROD) was determined in rat hepatocytes in primary culture and in the rat hepatoma cell line H4IIE. In rat hepatocytes, individual EC50-values and 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) equivalency factors (TEFs) for the non-ortho and mono-ortho coplanar PCBs 126, 169, 105, 118 and 156, were in good agreement with published data from in vivo experiments, while in H4IIE cells coincidence was lower. However, in both cell systems TEFs for PCB 77 were significantly higher than reported from experiments in rats. In an approximately equipotent mixture the six potent PCB congeners showed perfect additive behaviour in both cell systems. In contrast, addition of a tenfold surplus of abundant mono- and di-ortho PCBs (28, 52, 101, 138, 153 and 180) led to an almost threefold higher TEF than predicted. This finding suggests a moderate synergistic enhancement of the inducing potency of potent PCBs by less potent congeners, present in abundance in environmental and tissue samples. 相似文献
107.
Using an immunohistochemical approach we have characterized the in vivo developmental distribution of myelin oligodendrocyte glycoprotein within the rat CNS. Myelin oligodendrocyte glycoprotein expression emerged in a non-uniform manner during the first 3 postnatal weeks. Although it was absent throughout the CNS of the newborn rat at postnatal day 0(P0), it had appeared in the spinal cord and brainstem by P7. The forebrain and cerebellum remained devoid of immunoreactivity until after P14. Myelin oligodendrocyte glycoprotein emerged at different times within the closely associated fasciculi of the dorsal funiculus. It appeared in the fasciculus cuneatus during the first postnatal week and in the fasciculus gracilis and corticospinal tracts during weeks 2 and 3 respectively. Myelin oligodendrocyte glycoprotein expression developed along a caudo-rostral gradient from spinal cord to forebrain and along an antero-posterior gradient within the CNS in general. The relationship between the onset of myelin oligodendrocyte glycoprotein expression and myelinogenesis was also investigated. In most regions, myelin oligodendrocyte glycoprotein expression lagged behind the initial appearance of myelin basic protein and Luxol Fast Blue-stained myelin by at least 1 week. These observations support the idea that myelin oligodendrocyte glycoprotein is the latest myelin protein to appear in development, only being expressed during the final stages of oligodendrocyte differentiation. Furthermore, the pattern of staggered expression within the dorsal columns indicates that localized, region-specific interactions may comprise a key element in the control of the terminal phases of oligodendrocyte differentiation. 相似文献
108.
Nebulized Gadolinium‐Based Nanoparticles: A Theranostic Approach for Lung Tumor Imaging and Radiosensitization
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Sandrine Dufort Andrea Bianchi Maxime Henry François Lux Géraldine Le Duc Véronique Josserand Cédric Louis Pascal Perriat Yannick Crémillieux Olivier Tillement Jean‐Luc Coll 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(2):215-221
Lung cancer is the most common and most fatal cancer worldwide. Thus, improving early diagnosis and therapy is necessary. Previously, gadolinium‐based ultra‐small rigid platforms (USRPs) were developed to serve as multimodal imaging probes and as radiosensitizing agents. In addition, it was demonstrated that USRPs can be detected in the lungs using ultrashort echo‐time magnetic resonance imaging (UTE‐MRI) and fluorescence imaging after intrapulmonary administration in healthy animals. The goal of the present study is to evaluate their theranostic properties in mice with bioluminescent orthotopic lung cancer, after intrapulmonary nebulization or conventional intravenous administration. It is found that lung tumors can be detected non‐invasively using fluorescence tomography or UTE‐MRI after nebulization of USRPs, and this is confirmed by histological analysis of the lung sections. The deposition of USRPs around the tumor nodules is sufficient to generate a radiosensitizing effect when the mice are subjected to a single dose of 10 Gy conventional radiation one day after inhalation (mean survival time of 112 days versus 77 days for irradiated mice without USRPs treatment). No apparent systemic toxicity or induction of inflammation is observed. These results demonstrate the theranostic properties of USRPs for the multimodal detection of lung tumors and improved radiotherapy after nebulization. 相似文献
109.
Ultrasmall Nanoplatforms as Calcium‐Responsive Contrast Agents for Magnetic Resonance Imaging
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Albert Moussaron Sandip Vibhute Andrea Bianchi Serhat Gündüz Shady Kotb Lucie Sancey Vincent Motto‐Ros Silvia Rizzitelli Yannick Crémillieux Francois Lux Nikos K. Logothetis Olivier Tillement Goran Angelovski 《Small (Weinheim an der Bergstrasse, Germany)》2015,11(37):4900-4909
The preparation of ultrasmall and rigid platforms (USRPs) that are covalently coupled to macrocycle‐based, calcium‐responsive/smart contrast agents (SCAs), and the initial in vitro and in vivo validation of the resulting nanosized probes (SCA‐USRPs) by means of magnetic resonance imaging (MRI) is reported. The synthetic procedure is robust, allowing preparation of the SCA‐USRPs on a multigram scale. The resulting platforms display the desired MRI activity—i.e., longitudinal relaxivity increases almost twice at 7 T magnetic field strength upon saturation with Ca2+. Cell viability is probed with the MTT assay using HEK‐293 cells, which show good tolerance for lower contrast agent concentrations over longer periods of time. On intravenous administration of SCA‐USRPs in living mice, MRI studies indicate their rapid accumulation in the renal pelvis and parenchyma. Importantly, the MRI signal increases in both kidney compartments when CaCl2 is also administrated. Laser‐induced breakdown spectroscopy experiments confirm accumulation of SCA‐USRPs in the renal cortex. To the best of our knowledge, these are the first studies which demonstrate calcium‐sensitive MRI signal changes in vivo. Continuing contrast agent and MRI protocol optimizations should lead to wider application of these responsive probes and development of superior functional methods for monitoring calcium‐dependent physiological and pathological processes in a dynamic manner. 相似文献
110.
Bacterial strains of Aeromonas salmonicida included in the recognized subsp. acromogenes, subsp. masoucida, and subsp. smithia in addition to the large number of strains not included in any of the described subspecies are referred to as atypical A. salmonicida. The atypical strains form a very heterogeneous group with respect to biochemical characteristics, growth conditions, and production of extracellular proteasess. Consequently, the present taxonomy of the species A. salmonicida is rather ambiguous. Atypical A. salmonicida has been isolated from a wide range of cultivated and wild fish species, non-salmonids as well as salmonids, inhabiting fresh water, brackish water and marine environments in northern and central Europe, South Africa, North America, Japan and Australia. In non-salmonid fish species, infections with atypical strains often manifest themselves as superficial skin ulcerations. The best known diseases associated with atypical A. salmonicida are carp Cyprinus carpio erythrodermatitis, goldfish Carassius auratus ulcer disease, and ulcer disease of flounder Platichthys flesus, but atypical strains are apparently involved in more disease outbreaks than previously suspected. Macroscopical and microscopical studies of ulcerated fish indicate internal organs are infrequently invaded by atypical A. salmonicida. This view is supported by the fact that atypical strains are irregularly isolated from visceral organs of ulcerated fish. High mortality caused by atypical A. salmonicida has been observed in populations of wild non-salmonids and farmed salmonids, although the association between the mortality in the wild fish stocks and atypical A. salmonicida has not always been properly assessed. In injection experiments the pathogenicity of the atypical strains examined showed large variation. An extacellular A-layer has been detected in different atypical strains, but virulence mechanisms different from those described for (typical) A. salmonicida subsp. salmonicida, for example an extracellular metallo-protease and a different iron utilization mechanism, have been described. Limited information is available about the ecology, spread and survival of atypical strains in water. The commonly used therapeutic methods for the control of diseases in farmed fish caused by atypical A. salmonicida are generally effective against the atypical strains. Resistance to different antibiotics and transferable plasmid encoding multiple drug resistance have been observed in atpical A. salmonicida. Studies aimed at producing a vaccine against atypical strains are in progress. 相似文献