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41.
Zusammenfassung Autoradiographie von Gliazellen, welche regenerierende motorische Nervenzellen umgeben, ergab eine stark erhöhte DNA-Synthese in den Gliazellen zwischen dem zweiten und sechsten Tag nach dem Nervenschaden. Morphologisch erscheinen typische Gliaveränderungen mit hochgradiger Hypertrophie der Astrocyten in der zweiten und dritten Woche nach der Operation.  相似文献   
42.
Summary The penile artery of the bull contained significant amounts of acetylcholine, noradrenaline and dopamine, and its axon profiles contained either numerous small granular or agranular vesicles, as well as some large granular vesicles. In the dorsal metatarsal artery, only noradrenaline and dopamine were detectable, and the axon profiles observed contained numerous small granular vesicles. In the penile artery, the axons with small agranular vesicles, probably cholinergic axons, were in close contact with axons containing small granular vesicles. It is suggested that, in the penile artery of the bull, one of the functions of the cholinergic nerves is suppression of excitatory adrenergic neurotransmission.This study has been supported by grants from the Sigrid Jusélius Foundation (to O.E.), from the Medical Research Council of the Academy of Finland (to E.K.) and from the Magnus Bergvall Memorial Fund (to N.O.S.). Excellent technical assistance by Mrs Paula Hasenson and Miss Seija Ovaskainen is gratefully acknowledged.  相似文献   
43.
Résumé La prostaglandine E1 diminue les potentiels de jonction excitateurs du muscle lisse du vas deferens de cobaye en réponse à une stimulation nerveuse, mais provoque aussi une dépolarisation modérée de ce tissu. L'effet inhibiteur de la drogue sur la réponse motrice de cet organe à une stimulation nerveuse est attribué à la 1e de ces actions. L'effet stimulant sur la réponse motrice parfois constaté, est attribué à la seconde action.

The generous hospitality of ProfessorEdith Bülbring F. R. S. is gratefully acknowledged. The investigation was supported by a grant to ProfessorBülbring from the Medical Research Council.  相似文献   
44.
Summary Three types of axon profiles were observed in the smooth muscle of the retractor penis and the penile artery of the bull: 1. profiles containing small granular vesicles, presumably representing adrenergic axons; 2. profiles containing small agranular vesicles, presumably representing cholinergic axons; 3. profiles containing numerous large and small granular vesicles. The third type of profile was not found in the vas deferens or the metatarsal artery. It is therefore possible that this type of profile represents the non-adrenergic, non-cholinergic inhibitory nerves, the presence of which has previously been pharmacologically indicated in these tissues.This study has been supported by grants from the Sigrid Jusélius Foundation (to O. E.), from the Medical Research Council of the Academy of Finland (to E. K.) and from the Magnus Bergvall Memorial Fund (to N. O. S.). Excellent technical assistance by Mrs.Paula Hasenson is gratefully acknowledged.  相似文献   
45.
The mapping of the human genome is an important basis for the development of new medicals and medical treatments.Consequently,it has attracted tremendous research funding over the last decade.On June2011,the Materials Genome Initiative was announced by the US President Obama as collaboration on modeling and advanced materials databases.Unfortunately,the materials genome was given a rather vague definition in the announcement.However,the materials genome should be defined in analogy with biological genomes and one may then conclude that:at any moment,the performance of a specific material depends on its chemical composition(inherent property stored in its genome)and its environment(external interactions–processing–conditions during usage).The materials genome should thus be defined as a set of information encoded in the language of thermodynamics obtained by careful assessment of experimental data and quantum mechanical calculations from which certain conclusions about the material can be drawn.The CALPHAD databases contain the thermodynamic and kinetic properties of a materials system.Such databases allow the prediction of materials structure as well as its response to processing and usage conditions,and are major parts of integrated computational materials engineering.  相似文献   
46.
Molecular coupling of Tsix regulation and pluripotency   总被引:1,自引:0,他引:1  
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47.
Macrophage migration inhibitory factor (MIF), a small conserved protein, is abundant in the immune- and central nervous system (CNS). MIF has several receptors and binding partners that can modulate its action on a cellular level. It is upregulated in neurodegenerative diseases and cancer although its function is far from clear. Here, we report the finding of a new binding partner to MIF, the serine protease HTRA1. This enzyme cleaves several growth factors, extracellular matrix molecules and is implicated in some of the same diseases as MIF. We show that the function of the binding between MIF and HTRA1 is to inhibit the proteolytic activity of HTRA1, modulating the availability of molecules that can change cell growth and differentiation. MIF is therefore the first endogenous inhibitor ever found for HTRA1. It was found that both molecules were present in astrocytes and that the functional binding has the ability to modulate astrocytic activities important in development and disease of the CNS.  相似文献   
48.
The introduction of virtual reality (VR)-models in the city planning process will cause changes in the traditional roles of the involved parties. In order to better understand some of these changes, the events involving the use of VR-models in an architectural competition concerning rebuilding-proposals for the city library in a Swedish city were analyzed. The study shows that VR was introduced into the competition as an extra add-on and that the VR-presentation was experienced as useful by the jury. The transformation of the architects’ contributions into VR was experienced as problematic by the architects, partly because they lost full control over the presentation. In the future architects are likely to have to produce the VR-models for their proposals themselves. This may make it more difficult for smaller architectural firms to enter the market but their proposals will be more accessible to a wider group of stakeholders.  相似文献   
49.
This paper examines the efficiency and predictive power of implied forward shipping charter rates. In particular, we examine whether implied forward 6‐month time‐charter rates, which are derived through the difference between time‐charters with different maturities based on the term structure model, are efficient and unbiased predictors of actual future time‐charter rates. Using a dataset for the period January 1989 to June 2003, results of different statistical tests, including the cointegration approach, suggest that implied forward rates are in fact unbiased predictors of future time‐charter rates in the dry bulk freight market. In addition, it is found that implied forward rates yield superior forecasts compared to alternative univariate and multivariate time series models. However, while the unbiasedness hypothesis is found to hold, on average, we find that chartering strategies based on simple trend‐following trading rules in this cyclical market are able to generate economic profits even out‐of‐sample. This highlights how standard tests for unbiasedness do not always capture cyclical predictable components in the market behaviour. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
50.
Summary Plasminogen activator produced in organ culture of human kidney, i.e. in the histotypical arrangement of the tissue, was partially purified by affinity chromatography on para-aminobenzamidine coupled to Sepharose by a 6-carbon spacer, followed by gel chromatography on Sephadex G-100. The molecular weight of 2 active peaks were 27,000 and 52,000 daltons respectively. It was inhibited by DFP and by IgG antiurokinase.This study was supported by grant from the Swedish Medical Research Council (B77-17X-04523-03B).  相似文献   
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