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  • 1
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    German Medical Science GMS Publishing House; Düsseldorf
    In:  Deutscher Kongress für Orthopädie und Unfallchirurgie (DKOU 2017); 20171024-20171027; Berlin; DOCPO27-390 /20171023/
    Publication Date: 2017-10-23
    Keywords: os femoris ; parathyroid hormone ; osteoprotegerin ; sRANKL ; alkaline phosphatase ; osteocalcin ; TP1NP ; TRAP5b ; ICTP ; coxarthrosis ; bone fracture ; ddc: 610
    Language: English
    Type: conferenceObject
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  • 2
    ISSN: 0378-4347
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Springer
    Biological cybernetics 22 (1976), S. 181-188 
    ISSN: 1432-0770
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Computer Science , Physics
    Notes: Abstract The technique of subthreshold addition of sinusoidal gratings was used to analyse the visual system of man during the perception of edges, lines, and bars. The experimentally obtained sensitivity function varies in close relationship to the test pattern, and can be factorized into the conjugate complex spectrum of the test pattern at threshold and a pattern-invariant function of spatial frequency. Interpreting the sensitivity function as transfer function, which is possible under certain conditions, we can describe the visual system as a matched filter which extracts an input signal contaminated with noise of specified spectral energy density. Questions discussed refer to the spatial operations occurring in matched filters, the relationship between the modulation transfer function for sine-wave gratings and the pattern-invariant transfer component, the exact determination of elements within the theoretical concept, and the realization of matched filters by the nervous system.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1432-1106
    Keywords: Acetylcholine release ; Cholinergic neurons ; Dopamine release ; Dopaminergic transplants ; In vitro release ; Neuronal transplantation ; Nigrostriatal system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary The aim of the study was to examine the influence of intrastriatal dopaminergic grafts on the functioning of striatal cholinergic neurons using an in vitro superfusion method. Rats bearing unilateral 6-hydroxydopamine lesion of the nigrostriatal dopaminergic system received a cell suspension obtained from ED 14 rat embryonic mesencephali which was injected into the denervated striatum. Lesioned animals displayed an ipsilateral rotation in response to amphetamine (5 mg/kg i.p.). This rotational response disappeared following grafting and there was even a significant contralateral rotation in response to the drug. Apomorphine (0.1 mg/kg s.c.) induced a contralateral rotation following the lesion. This latter response was attenuated in the grafted group. Three months after grafting 350 μm thick slices were prepared from striata from the control and experimental sides of lesioned and graft-bearing animals. The slices were preincubated either with 3H-dopamine (10-7 M) or 3H-choline (10-7 M) and then superfused with an oxygenated Krebs-Ringer solution. Stimulation with electrical pulses following preincubation with 3H-dopamine elicited a marked increase of tritium outflow from control slices. Stimulation-evoked overflow was of similar magnitude from slices from striata containing the graft, while it was much reduced in slices from lesioned striata. Amphetamine markedly potentiated the effect of electrical stimulation in slices obtained from control and graft-containing striata. Nomifensine (a dopamine uptake blocker) led to a significant decrease of the overflow of 3H-acetylcholine evoked by electrical stimulation from control striatal slices. This inhibition was antagonized by domperidone, a D2 dopamine receptor blocker, a finding which indicates that the action of nomifensine was indeed due to a potentiation of the action of endogenous dopamine released by the electrical stimulation. A similar, although somewhat attenuated, action of nomifensine and domperidone was observed for striatal slices containing the graft. Amphetamine inhibited the stimulation evoked overflow of 3H-acetylcholine in a dose-dependent manner from striatal slices obtained both from the intact and experimental sides of graft-bearing animals, while it had no action on slices from denervated striata. Finally, the dose-response curve for the inhibition of 3H-acetylcholine release by apomorphine was significantly shifted to the left for slices from the lesioned striata as compared with control slices. This leftward shift was totally abolished in the slices from the graft-containing striatum. These results indicate that the dopaminergic inhibition of the striatal cholinergic interneurons, abolished by the lesion, is restored by intrastriatal dopaminergic grafts both in vitro and in vivo. On the other hand the lack of correlation between the in vivo and the in vitro effects (rotational response vs. inhibition of 3H-acetylcholine release) suggest that the effect of such grafts on rotational behavior cannot be explained solely by their action on the striatal cholinergic neurons.
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Biological cybernetics 14 (1973), S. 185-185 
    ISSN: 1432-0770
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Computer Science , Physics
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 449 (2007), S. 803-803 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] More than a century ago, Robert Koch established that infectious diseases are caused by microbes, a discovery that won him the Nobel Prize in Physiology or Medicine in 1905. At around the same time, Ilya Mechnikov, one of the pioneers of cellular immunology, was the first to recognize that microbes ...
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  • 7
    ISSN: 1365-2958
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology , Medicine
    Notes: Bacterial quorum sensing using acyl-homoserine lactones (acyl-HSLs) as cell-density dependent signalling molecules is important for the transcriptional regulation of many genes essential in the establishment and the maintenance of bacteria–host associations. Vibrio fischeri, the symbiotic partner of the Hawaiian bobtail squid Euprymna scolopes, possesses two distinct acyl-HSL synthase proteins, LuxI and AinS. Whereas the cell density-dependent regulation of luminescence by the LuxI-produced signal is a well-described phenomenon, and its role in light organ symbiosis has been defined, little is known about the ain system. We have investigated the impact of the V. fischeri acyl-HSL synthase AinS on both luminescence and symbiotic colonization. Through phenotypic studies of V. fischeri mutants we have found that the AinS-signal is the predominant inducer of luminescence expression in culture, whereas the impact of the LuxI-signal is apparent only at the high cell densities occurring in symbiosis. Furthermore, our studies revealed that ainS regulates activities essential for successful colonization of E. scolopes, i.e. the V. fischeri ainS mutant failed to persist in the squid light organ. Mutational inactivation of the transcriptional regulator protein LuxO in the ainS mutant partially or completely reversed all the observed phenotypes, demonstrating that the AinS-signal regulates expression of downstream genes through the inactivation of LuxO. Taken together, our results suggest that the two quorum-sensing systems in V. fischeri, ain and lux, sequentially induce the expression of luminescence genes and possibly other colonization factors.
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  • 8
    ISSN: 1471-4159
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Abstract: Slices from human neocortex preincubated with [3H]serotonin ([3H]5-HT) were superfused and stimulated electrically to investigate whether the α2-adrenoceptors on serotonergic terminals can be stimulated by endogenous noradrenaline (NA) released from neighboring noradrenergic fibers. The stimulation-evoked 3H overflow, representing action potential-induced, exocytotic release of 5-HT, was depressed by the NA uptake blocker (+)-oxaprotiline. Rauwolscine (a mixed α2-adrenoceptor antagonist/5-HT autoreceptor agonist) or phentolamine [a combined α- adrenoceptor/5-HT autoreceptor antagonist; the latter drug in the presence of (+)-oxaprotiline] enhanced the release when the 5-HT autoreceptors had previously been blocked by metitepine. Under hypothermia the release of 5-HT was found to be decreased and that of NA to be increased; under these conditions idazoxan (an α2-adrenoceptor antagonist) enhanced the release of 5-HT. In neocortex slices from rats (+)-oxaprotiline similarly depressed the release of 5-HT (measured with the same methods) as in human tissue. When rats were pretreated with 6-hydroxydopamine, the inhibitory effect of exogenous NA on 5-HT release was increased, and in slices from rats pretreated with desipramine, it was decreased. In conclusion, α2-heteroreceptors can be activated by endogenous NA released from neighboring noradrenergic fibers. Because regulatory processes analogous to those in rats probably occur in humans as well, an up- or down-regulation of α2- heteroreceptors in depressed patients with a (pathological) decrease or a (therapeutic) enhancement of the noradrenergic neurotransmission may also be assumed to occur.
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  • 9
    ISSN: 1432-2072
    Keywords: Caudate nucleus ; Hippocampus ; Serotonin ; Dopamine ; Chlorimipramine ; Fluvoxamine ; 6-Nitroquipazine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Slices of rabbit hippocampus or caudate nucleus were incubated with [3H]-5-HT (0.1 µM, 60 min) or with [3H]-DA. In hippocampal tissue, the 5-HT uptake blockers chlorimipramine, fluvoxamine, and 6-nitroquipazine (0.1, 1, 10 µM) reduced the percentage content of [3H]-5-HT in a concentration dependent manner. The degree of inhibition of [3H]-5-HT content produced by the 5-HT uptake inhibitors was not affected by the MAO inhibitors pargyline or amezinium (which by themselves enhanced [3H] loading) or the catecholamine uptake inhibitor nomifensine (which by itself did not affect [3H] loading). In caudate nucleus tissue, however, the [3H]-5-HT accumulation was reduced only at the highest concentration of the 5-HT uptake blockers (10 µM). In the additional presence of the MAO inhibitors or nomifensine (which by themselves increased or diminished, respectively, the [3H] labelling) the 5-HT uptake inhibitors became more potent in reducing the percentage [3H]-5-HT accumulation of caudate nucleus slices. These results indicate (1) that a false labelling of [3H]-5-HT into dopaminergic terminals in the caudate nucleus can be prevented by nomifensine, (2) that the 5-HT uptake blockers seem to accumulate within the dopaminergic terminals, where they may display a MAO inhibitory property. The 5-HT uptake blockers were ineffective on the percentage tritium accumulation of caudate nucleus slices incubated with [3H]-DA, regardless of the presence of pargyline or nomifensine. Tritiated DA and deaminated [3H]-metabolites were separated in the superfusate of [3H]-DA-release experiments in caudate nucleus tissue. In the presence of 6-nitroquipazine the percentage efflux of unmetabolized [3H]-DA was significantly enhanced in a concentration and time dependent manner. In comparison to 6-nitroquipazine, fluvoxamine was less potent in that respect. 6-Nitroquipazine inhibited the electrically evoked [3H]-DA and [3H]-ACh release from caudate nucleus slices in a concentration dependent manner. The effects on [3H]-DA release were abolished in the presence of pargyline. The inhibition of [3H]-ACh release was significantly diminished by the D2-receptor antagonist domperidone. In conclusion, some 5-HT-related drugs may diminish the release of ACh from caudate nucleus slices via an enhanced dopaminergic transmission due to inhibition of MAO within the dopaminergic terminals.
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  • 10
    ISSN: 0170-2041
    Keywords: Chemistry ; Organic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Strukturaufklärung der Peptidantibiotika Herbicolin A und BDie Struktur der amphiphilen Peptidantibiotika Herbicolin A und B konnte mit physikalischen Methoden sowie durch chemischen Abbau und Partialsynthesen identifiziert werden. Herbicolin B ist ein Lipodepsipeptid der Sequenz DH-Abu-L-Thr-D-aThr-D-Leu-Gly-D-Gln-Gly-N-Me-L-aThr-L-Arg (DH-Abu = 2,3-Dehydro-α-aminobuttersäure), dessen C-terminaler Argininrest mit der Hydroxygruppe von L-Thr lactonisiert und dessen N-Terminus durch (R)-3-Hydroxytetradecansäure acyliert ist. In der Hauptkomponente Herbicolin A ist im Unterschied zu Herbicolin B zusätzlich ein Molekül D-Glucose 1-α-glycosidisch mit der 3-Hydroxytetradecansäure verknüpft. Somit ist Herbicolin A das erste bekannte Glycolipodepsinonapeptid-Antibiotikum.
    Notes: The structures of the amphiphilic peptide antibiotics herbicolin A and B were determined by application of physical methods, chemical degradation, and partial syntheses. Herbicolin B is a lipodepsinonapeptide with the sequence DH-Abu-L-Thr-D-aThr-D-Leu-Gly-D-Gln-Gly-N-Me-L-aThr-L-Arg (DH-Abu = 2,3-dehydro-α-aminobutyric acid). The C-terminal Arg residue forms a lactone ring with the hydroxy group of L-Thr, while the N-terminus is acylated by an (R)-3-hydroxytetradecanoic acid residue. The main component herbicolin A differs from herbicolin B in an additional D-glucose moiety linked in an 1-α-glycosidic bond to the 3-hydroxytetradecanoic acid residue. Thus herbicolin A constitutes the first glycolipodepsinonapeptide antibiotic known so far.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
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