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41.
Adrenergic and dopaminergic response to chronic chair restraint in the rhesus monkey. 总被引:4,自引:0,他引:4
Prolonged chair restraint and social isolation in the rhesus monkey led to a reduction in the urinary excretion of HVA (4-hydroxy-3-methoxyphenylacetic acid), DOPAC (3,4-dihydroxyphenylacetic acid), VMA methoxy-4-hydroxymandelic acid), and MHPG (3-methoxy-4-hydroxyphenylethylglycol) over a 3 week period. This adaptation to a chronically "stressful" situation corresponds to earlier studies on the rhesus monkey indicating a gradual reduction in the urinary excretion of norepinephrine and epinephrine after initiation of restraint. The following basic information on the urinary excretion of catecholamine metabolites was obtained: (1) the rate of excretion of the dopamine metabolites (HVA and DOPAC) is about four times higher than the rate of excretion of adrenergic metabolites (VMA and MHPG): (2) MHPG is the major adrenergic metabolite in the rhesus monkey; and (3) the excretion rates of the urinary metabolites varied considerably between animals. 相似文献
42.
43.
Ch. Ell J. Braun H. J. König S. Domschke W. Domschke 《Journal of molecular medicine (Berlin, Germany)》1985,63(12):572-574
Summary The pharmacokinetics of high-dose metoclopramide (10 mg/kg body wt. in five infusions of 2 mg/kg body wt. each) was studied in 11 patients (5 females, 6 males) in two groups: group A with and group B (consisting of five patients) without forced diuresis. When the drug was infused, forced diuresis had no influence on the pharmacokinetics of metoclopramide (serum level after the 1st infusion was 851±361 ng/ml in group A versus 840±348 ng/ml in group B; after the 5th infusion it was 2,005±588 ng/ml in group A versus 2,463±1,350 ng/ml in group B). There were significant differences in the 24-h serum levels (582±308 ng/ml in group A versus 379±170 ng/ml in group B;P<0.05) and in the elimination half life (8.5±2.6 h in group A versus 6.1±1.1 h in group B;P<0.05). The results demonstrate that the dosage regimen originally suggested by Gralla for cytostatic drugs, with forced diuresis for high-dose metoclopramide therapy, may also be applied, with no dosage reduction, with to other cytostatic drugs which do not require forced diuresis. 相似文献
44.
A. Braun 《Medical microbiology and immunology》1960,147(1):79-93
Zusammenfassung Es wird über Erfahrungen bei der Typenbestimmung von 127 Tuberkelbakterien-Stämmen berichtet, die aus menschlichen Untersuchungsstoffen (95), Organen perlsüchtiger Rinder (15) und Organen tuberkulöser Hühner (17) gezüchtet wurden. Zur Differenzierung zogen wir die kulturmorphologischen Eigenschaften, den Bromkresolpurpur-Nährboden (Wagener u.Mitscherlich), die Feststellung des O2-Bedarfes (Lebek), die Katalase-Aktivität (Middlebrook), den Niacin-Test (Bönicke u.Lisboa), die Testung gegenüber Brenzschleimsäurehydracid (Bönicke u.Lisboa) und Tierversuche heran. Schwierigkeiten entstanden nur bei fermentschwachen und isoniazid-resistenten Stämmen beider Säugetiertypen der Tuberkelbakterien. Dabei verhielt sich keines der Verfahren immer typengerecht. Die Typendiagnose kann also nur unter Auswertung mehrerer Methoden gewonnen werden.Auf den kürzlich vonBönicke empfohlenen Nicotinamidase-Test zur Identifizierung schwierig einzuordnender, auch isoniazidresistenter Stämme wurde hingewiesen.Der Brenzschleimsäurehydrazid-Test und die Methode der Prüfung des O2-Bedarfes eignen sich nach unseren Beobachtungen nicht für die Erkennung von Geflügeltuberkelbakterien. 相似文献
45.
Patient motion occurring during data acquisition in single photon emission computed tomography (SPET) can cause serious reconstruction artefacts. We have developed a new approach to correct for head motion in brain SPECT. Prior to motion, projections are assigned to conventional projections. When head motion occurs, it is measured by a motion monitoring system, and subsequent projection data are mapped to 'virtual' projections. The appropriate position of each virtual projection is determined by applying the converse of the patient's accumulated motion to the actual camera projection. Conventional and virtual projections, taken together, form a consistent set that can be reconstructed using a three-dimensional (3D) algorithm. The technique has been tested on a range of simulated rotational movements, both within and out of the transaxial plane. For all simulated movements, the motion corrected images exhibited better agreement with a motion free reconstruction than did the uncorrected images. This technique may help to overcome one of the major remaining limitations on image quality and quantitative accuracy in SPECT. 相似文献
46.
Boldogköi Zsolt Braun Attila Medveczky István Glávits Róbert Gyúró Bence Fodor István 《Virus genes》1998,17(1):89-98
A recombinant pseudorabies (Aujeszky’s disease) virus (PrV) designated as vE16lac was constructed by deleting a 3-kbp DNA
segment spanning the junction of long and short components of the viral genome, and by replacing the deleted segment with
a lacZ-expression cassette. The aim of constructing this mutant was (a) to determine whether the terminal repeat (Tr) can
serve as a template for the regeneration of the internal repeat (Ir), and (b) whether this deletion causes a reduction in
the neuroinvasiveness of the virus. To analyze the mechanism of equalization, revertant viruses were selected and structurally
characterized from vE16lac infection of PK-15 cells, mice and pigs. Because all revertants acquired Ir sequences identical
to that of the wild-type virus, the equalization process occurred using the Tr as a template to reconstitute the Ir. We also
found that the recombinant virus vE16lac was virulent in both pigs and mice. The data are discussed in view of studies performed
with similar PrV mutants by other authors (Rall et al., 1992, Dean and Cheung, 1995 and Dean et al., 1996).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
47.
Andrzej Bedzki Henri Balard Dietrich Braun 《Macromolecular chemistry and physics.》1981,182(4):1057-1062
The telechelics 1 from methyl methacrylate and 1,1,2,2-tetraphenyl-1,2-diphenoxyethane, can be separated by adsorption chromatography. The structure of the dimers and trimers was identified by 1H NMR-spectroscopy. The free radical oligomerization is a process in which the syndiotactic structure is favoured above the isotactic one. 相似文献
48.
Ohne ZusammenfassungFür die Überlassung des Themas und die wertvollen Anregungen bin ich meinem hochverehrten Lehrer, Herrn Prof. Dr. Dr. R. Lehmensick, zu größtem Dank verpflichtet. 相似文献
49.
Characterization of a Xenopus laevis CXC chemokine receptor 4: implications for hematopoietic cell development in the vertebrate embryo 总被引:3,自引:0,他引:3
Moepps B Braun M Knöpfle K Dillinger K Knöchel W Gierschik P 《European journal of immunology》2000,30(10):2924-2934
Previous reports have shown that the Gi-protein-coupled CXC chemokine receptor 4 is activated by stromal cell-derived factor 1 (SDF-1). The receptor is present in many cell types and regulates a variety of cellular functions, including chemotaxis, adhesion, hematopoiesis, and organogenesis. To examine the role of CXCR4 as a regulator of organogenesis in the vertebrate embryo, we have isolated a cDNA encoding the Xenopus laevis homologue of CXCR4 (xCXCR4). The encoded polypeptide was functionally reconstituted with recombinant Gi2 in baculovirus-infected insect cells. Although xCXCR4 shares only 42% of its extracellular residues with mammalian CXCR4, it is indistinguishable from human CXCR4 in terms of its activation by human SDF-1alpha and SDF-1beta. The fact that only 19 of these residues are specifically present in the extracellular portions of CXCR4 suggests that these residues may be involved in recognizing SDF-1 and/or mediating CXCR4 activation by SDF-1. Xenopus CXCR4 mRNA expression was up-regulated during early neurula stages and remained high during early organogenesis. Whole mount in situ hybridization analysis showed abundant expression of xCXCR4 mRNA in the nervous system, including forebrain, hindbrain, and sensory organs, and in neural crest cells. xCXCR4 mRNA was also detected in the dorsal lateral plate, the first site of definitive hematopoiesis in the amphibian embryo corresponding to aorta-gonad-mesonephros or para-aortic splanchnopleura in mammals. This observation suggests that SDF-1 and CXCR4 are involved in regulating the migratory behavior of hematopoietic stem cells colonizing the larval or fetal liver. The hematopoietic defects observed in mice lacking SDF-1 or CXCR4 may, at least in part, be explained by a disturbance of this migration. 相似文献
50.
New monomers with sterically hindered free or blocked phenolic hydroxyl groups were used as starting compounds for the preparation of stable oxygen polyradicals. In this paper the synthesis of these monomers is described: 2,6-Di-(tert-butyl)-4-vinylphenol was obtained by decarboxylation of 3-[3,5-di-(tert-butyl)-4-hydroxyphenyl]acrylic acid in yields of 80–;90%. 2,6-Di-(tert-butyl)-4-isopropenylphenol was prepared from 3,5-di-(tert-butyl)-4-hydroxyphenyl methyl ketone and methyl iodide by a GRIGNARD reaction followed by the dehydration of 2-[3,5-di-(tert-butyl)-4-hydroxyphenyl]-2-propanol. 2,6-Di-(tert-butyl)-4-isopropenylphenyl methyl ether was obtained with 64% yield from 3,5-di-(tert-butyl)-4-methoxybenzonitrile by two consecutive GRIGNARD reactions with methyl iodide via the unknown compounds 3,5-di-(tert-butyl)-4-methoxyphenyl methyl ketone and 2-[3,5-di-(tert-butyl)-4-methoxyphenyl]-2-propanol, followed by dehydration of the tertiary alcohol with 89% phosphoric acid. 相似文献