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Zusammenfassung An Hand von 2jährigen Pfropfversuchen wird die Möglichkeit der Freilandsommerpfropfung bei Koniferen nachgewiesen. Die Erfolge waren bei der Kiefer und Fichte beachtlich hoch und übertreffen die Ergebnisse der Frühjahrspfropfungen beträchtlich. Es wird festgestellt, daß am Pfropftag die Maximaltemperatur, Niederschläge und relative Luftfeuchtigkeit für das Ergebnis der Pfropfungen wichtig sind.Mit 4 Textabbildungen  相似文献   
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In addition to their degradative role in protein turnover, proteases play a key role as positive or negative regulators of signal transduction pathways and therefore their dysregulation contributes to many disease states. Regulatory roles of proteases include their hormone-like role in triggering G protein-coupled signaling (Protease-Activated-Receptors); their role in shedding of ligands such as EGF, Notch and Fas; and their role in signaling events that lead to apoptotic cell death. Dysregulated activation of apoptosis by the caspase family of proteases has been linked to diseases such as cancer, autoimmunity and inflammation. In an effort to better understand the role of proteases in health and disease, a luciferase biosensor is described which can quantitatively report proteolytic activity in live cells and mouse models. The biosensor, hereafter referred to as GloSensor Caspase 3/7 has a robust signal to noise (50–100 fold) and dynamic range such that it can be used to screen for pharmacologically active compounds in high throughput campaigns as well as to study cell signaling in rare cell populations such as isolated cancer stem cells. The biosensor can also be used in the context of genetically engineered mouse models of human disease wherein conditional expression using the Cre/loxP technology can be implemented to investigate the role of a specific protease in living subjects. While the regulation of apoptosis by caspase''s was used as an example in these studies, biosensors to study additional proteases involved in the regulation of normal and pathological cellular processes can be designed using the concepts presented herein.  相似文献   
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Pigment-epithelium-derived factor (PEDF) is a 50-kDa glycoprotein with well-recognised expression in various mammalian organs showing diverse (e.g. anti-angiogenic and neuroprotective) activities. However, at present, no information is available regarding the potential function of this cytokine in the inner ear. As a first approach to investigating whether PEDF is involved in cochlear function, we have explored its protein expression in the rat cochlea by immunocytochemistry. Our results show that PEDF expression in the cochlea is most prominent in the basilar membrane below the organ of Corti, in the lateral wall (especially in the stria vascularis), in ganglion neurons, and in the endothelia of blood vessels. Our findings on its distribution in the cochlea suggest that PEDF in the basilar membrane prevents blood vessel formation that would disturb cochlear micromechanics and would interfere with the mechano-electrical transduction in the organ of Corti. In cochlear ganglion neurons, PEDF might serve a neuroprotective function possibly protecting these neurons from excessive glutamate released by the inner hair cells. Our data constitute the first report on the morphological protein distribution of this multifunctional molecule in the rat cochlea and suggest its role in important functions of the internal ear. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorised users.  相似文献   
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