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41.
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We present a heterogeneous non-competitive immunological detection assay for peptide and protein antigens from crude extracts of biological sources. This time-resolved fluoroimmunoassay (TR-FIA) has been designed in a solid-phase mode using 96-well microtiter plates. Using the rare-earth metal europium as a fluorescent marker, a highly sensitive, selective and efficient procedure was developed. This technique prevents from interferences of intrinsic protein fluorescence which is highly important for antigen measurement in complex matrices. The TR-FIA has been applied for the detection of circulating forms of the potential anti-tumor agent endostatin, a C-terminal fragment of collagen XVIII, and its close homolog collagen XV (restin) from hemofiltrate. Endostatin was detected with a limit of detection of 3 ng (150 fmol/well) and a broad dynamic range from 10-1000 ng/well.  相似文献   
43.
The authors add to the literature a case report of a 32-year-old man with an intramedullary epidermoid cyst at the level of D 3/4, that was successfully operated on. There are several previous reports in the literature, but only five of these include MRI studies.  相似文献   
44.
Zusammenfassung. Die Klonierung, Sequenzierung und Produktion von hochreinen Allergenen bietet die Möglichkeit, perfekt standardisierte Allergenpräparate herzustellen. Die Entwicklung eines neuen Klonierungssystems, das auf filamentösen Phagen basiert, führte zu einer schnellen Isolierung und Charakterisierung von Aspergillus fumigatus-Allergenen. Die auf diesem Weg rekombinant hergestellten Proteine wurden serologisch und klinisch geprüft und ihr routinemä-ßiger Einsatz im ImmunoCAP-System evaluiert. Es gelang eine quantitative Übereinstimmung zwischen Hauttestergebnissen und Serologie nachzuweisen, welche das Potential rekombinanter Allergene in der Diagnostik allergischer Krankheiten aufzeigt. Darüber hinaus trägt die Charakterisierung der Pilzallergene wesentlich zum Verständnis der moiekularen Natur der allergieauslösenden Komponenten bei Zum jetzigen Zeitpunkt können, abgesehen von Proteinen mit unbekannten biologischen Funktionen, die Pilzallergene in zwei Klassen eingeteilt werden: 1. Spezies-spezifische sezcrnierte Allergene und 2. cytoplasmatische, hoch konservierte Proteine. Diese letztgenannten Pilzallergene zeigen auch zu Proteinen aus phylogenetisch weit entfernten Organismen weitreichende Sequenzhomologien. Neben der daraus zu erwartenden IgE-Kreuzreaktivität findet man in einigen Fällen auch eine Kreuzreaktivität mit den homologen humanen Proteinen, was auf Autoimmunreaktionen, bei Pilzalleigien hindeutet. Summary. Cloning, sequencing and production of highly pure recombinant allergens allows to produce perfectly standardised allergen preparations. The development of a new cloning system based on filamentous phage allowed the fast isolation and characterisation of allergens from the fungus Aspergillus fumigatus. The produced recombinant allergens were tested in serological and clinical studies as well as for their performance for routine assessments in the ImmunoCAP-system. Thereby, a perfect correlation between skin test results and serology was found showing the potential of recombinant allergens for the diagnosis of allergic diseases. Moreover, the characterisation of fungal allergens substantially contributes to our understanding of the molecular nature of proteins involved in the elication of allergic reactions. Apart from allergenic proteins with unknown biological function, fungal allergens can be subdivided into two classes: 1. Species-specific, secreted proteins and 2. cytoplasmic, even in phylogenetically distant organisms, well conserved proteins. These fungal allergens show extended sequence similarity, a high level of IgE cross-reactivity and in some cases also cross-reactivity with homologous human proteins indicating autoimmune reactions involved in fungal allergy.  相似文献   
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Transcorneal in vitro permeation studies of ophthalmic drugs are normally performed with either excised animal corneas or latterly corneal cell culture models. A good correlation between these models and excised animal corneas regarding permeation behaviour of drugs has already been shown. However, comparisons between corneal in vitro models containing human cells and excised human corneas do not exist yet. Therefore in the present study the transcorneal permeation of six different model drugs (pilocarpine hydrochloride, befunolol hydrochloride, hydrocortisone, diclofenac sodium, clindamycin hydrochloride and timolol maleate) across our previously described three-dimensional organotypic human cornea construct (HCC) was tested using Franz diffusion cells and compared with permeation data obtained from human donor corneas. The HCC showed a similar permeation behaviour compared with human donor cornea for all substances. The permeabilities (permeation coefficients P) of the human cornea equivalent versus the human donor cornea were the same in the case of diclofenac, clindamycin, timolol, but marginally decreased for hydrocortisone and slightly increased for pilocarpine and befunolol. These small differences of permeation coefficients were expressed as factors and only varied from 0.8 to 1.4. The results indicate that the HCC may be an alternative for in vitro permeation studies and appropriate for predicting drug absorption into the human eye.  相似文献   
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The field of chemical rodent control has seen no major developments in the last decades, even though anticoagulant rodenticides (AR), the mainly used substances to manage mice and rats, are known environmental pollutants and candidates for substitution under the European Biocidal Products Regulation 528/2012. Moreover, recent political developments in Europe and the USA demand more safety and sustainability in the management of chemicals, reinforcing the need for environmentally friendly substances. In this concept study, we present a step-by-step approach to improve the environmental properties of rodenticides. Repurposing of existing pharmaceuticals, the use of enantiomerically pure rodenticides, or the improvement of the formulation by microencapsulation can help to alleviate environmental problems caused by AR in the short term. Modification of the chemical structures or the development of prodrugs as medium-term strategies can further improve environmental properties of existing compounds. Ultimately, the development of new substances from scratch enables the utilisation of so far ignored modes of actions and the application of modern safe and sustainable-by-design principles to improve target specificity and reduce the negative impact on non-target organisms and the environment. Overall, our concept study illustrates the great potential for improvement in the field of chemical rodent control when applying available techniques of green and sustainable chemistry to known or potential rodenticides. Most promising in the medium term is microencapsulation that would allow for the use of acutely acting substances as it could circumvent bait shyness. On a longer timescale the de novo design of new rodenticides, which is the only method that can combine a high target specificity with good environmental properties, is the most promising approach.  相似文献   
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Conflict monitoring and motor inhibition are engaged in the performance of complex tasks. The midcingulate cortex (MCC) has been suggested to detect conflicts, whereas the right inferior frontal cortex (IFC) seems to be of relevance for the inhibition process. The current experiment investigates the neural underpinnings of their interplay via a modified flanker paradigm. Conflict was manipulated by the congruency of flanking stimuli relative to a target (congruent vs. incongruent) and motor inhibition by a within‐trial response change of the initiated response (keep response vs. stop‐change). We used event‐related functional magnetic resonance imaging, decomposition with high model order ICA, and single trial analysis to derive a functional parcellation of the whole‐brain data. Results demonstrate the segmentation of the MCC into anterior and posterior subregions, and of the IFC into the pars opercularis, pars triangularis, and pars orbitalis. The pars opercularis and pars triangularis of the right IFC constituted the foundation of inhibition‐related networks. With high conflict on incongruent trials, activity in the posterior MCC network, as well as in one right IFC network was observed. Stop‐change trials modulated both the MCC as well as networks covering extended parts of the IFC. Whereas conflict processing and inhibition most often are studied separately, this study provides a synopsis of functionally coupled brain regions acting in concert to enable an optimal performance in situations involving interference and inhibition. Hum Brain Mapp, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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