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101.
RM Zaslavskaia SI Logvinenko AG Logvinenko MM Te?blium 《Canadian Metallurgical Quarterly》1997,(2):23-27
The circadian pattern of hemocoagulation was studied in patients with decompensated rheumatic heart disease (DRHD) concurrent with stages I-II circulatory failure (CF) during complex treatment or medical treatment with disaggregants. Biorhythmological studies demonstrated that in patients with DRHD and CF chronotherapy with curantyl had some advantages over the traditional therapy during complex drug therapy. In these patients, the chronopatterns of circadian rhythms of hemocoagulative parameters tended to normalize under the influence of curantyl chronotherapy, by diminishing the signs of external desynchronization. Advantages of chronotherapy over the traditional treatment found in patients with DRHD and stages I-II CF, as manifested by its clinical effect in shorter periods (on days 4-5) when small daily and course doses of the drug were used. Based on the biorhythmological studies of hemostatic parameters, a method of curantyl chronotherapy was developed for patients with DRHD and stages I-II CF, which may optimize the therapeutical process in patients with this abnormality. 相似文献
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M Dols MR Simeon RM Willemot MR Vignon PF Monsan 《Canadian Metallurgical Quarterly》1997,305(3-4):549-559
The glucooligosaccharides (GOS), produced by Leuconostoc mesenteroides NRRL B-1299 dextransucrase through an acceptor reaction with maltose and sucrose, were purified by reverse phase chromatography. Logarithmic plots of retention time vs. dp of the GOS gave three parallel lines suggesting the existence of at least three families of homologous molecules. The structure (13C and 1H NMR spectroscopy) and reactivity of the purified molecules of the three families were investigated. All the products bear a maltose residue at the reducing end. The GOS in the first family (named OD) contained additional glucosyl residues all alpha-(1-->6) linked. The smallest molecule in this first series was panose or alpha-D-glucopyranosyl-(1-->6)-D-maltose (dp 3). All the OD molecules were shown to be good acceptors for dextransucrase in the presence of sucrose. The second family, named R, was composed of linear GOS containing alpha-(1-->6)-linked glucosyl residues and a terminal alpha-(1-->2)-linked residue at the non-reducing end of the molecule; the smallest molecule in this family was alpha-D-glucopyranosyl-(1-->2)-D-panose (dp 4). The third family, R', was formed of GOS containing additional residues linked through alpha-(1-->6) linkages that constitute the linear chain, and an alpha-(1-->2)-branched residue located on the penultimate element of the chain, near the non-reducing end. The smallest molecule in this series is alpha-D-glucopyranosyl-(1-->6)-[alpha-D-glucopyranosyl-(1-->2)]-alpha-D- glucopyranosyl-(1-->6)-D-panose, dp 6. R and R' GOS are very poor acceptors for L. mesenteroides NRRL B-1299 dextransucrase. This study makes it possible to suggest a rather simple reaction scheme, where molecules Ri, R'i and ODi of the same dp all result from the glucosylation of the same GOS: ODi-l. 相似文献
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Site-specific regeneration of the liver after 70% partial hepatectomy was investigated noninvasively in terms of protein synthesis using PET with L-[methyl-11C]methionine in a living animal. Protein synthesis in rat liver at 24 hr after partial hepatectomy did not occur uniformly in the whole liver but intensely in the middle part of the regenerating organ in comparison with the other parts. The activity was significantly low at the posterior aspect of the liver. On the other hand, site-specific protein synthesis was not observed in normal liver. These results were confirmed by bioimaging analyzer system (BAS) analysis, an invasive method that indicates radioactivities of precise intrahepatic sites. DNA synthesis in regenerating liver was also monitored with [2-14C]thymidine and analyzed by BAS 24 hr after 70% hepatectomy. Site-specific DNA synthesis in regenerating liver corresponding to the protein synthesis was also observed by BAS analysis. These results indicate that liver regeneration occurs intensely in the middle part of the liver and that PET enables noninvasive in vivo biochemical analysis. 相似文献
105.
Structural analogues of ZAPA, Z-3-[(aminoiminomethyl)thio]prop-2-enoic acid, an isothiouronium analogue of GABA, are potent GABAA agonists as seen in the isolated guinea-pig ileum and in the facilitation of [3H]diazepam binding to rat brain membranes. Compounds with guanidino or amidine groups replacing the amino functionality of GABA were also found to be active. The highest activity was displayed by the isothiouronium salts in which the conformational flexibility of the molecule is restricted by a Z-substituted carbon-carbon double bond. A series of bis-isothiouronium compounds was prepared from aliphatic alpha, omega-bis-thioureas as mixtures of E and Z adducts. Maximum GABAA agonist activity for this series was found with a C6-C8 carbon chain, and the results were consistent with an interaction at the GABAA receptor with only one end of the molecule, rather than the more potent effect expected of a molecule bridging two active sites. GABAA antagonist/partial agonist activity was observed on the guinea pig isolated ileum for a number of different analogue types, with the most potent being bis-isothiouronium derivatives. None of the substituted derivatives of ZAPA was as active as ZAPA itself, and maximum GABAA activity was found in the n-pentyl and n-hexyl analogues. 相似文献
106.
DE Anderson G St-Jean DC Richardson RM DeBowes JK Roush SR Lowry PW Toll HM Aberman DC Van Sickle JJ Hoskinson 《Canadian Metallurgical Quarterly》1997,68(6):571-576
The analysis of health state of drivers sent for an extra health examination for the estimation of driving capability for the driving of motor vehicle in alcoholic state was presented. The study included 380 drivers who were found driving drunk by traffic police (studied group) and 180 drivers of control group sent for an extra health examination for some other reason. The disorders in psychomotor sphere were noticed in the drivers of studied group and it was determined that they had caused significantly larger number of traffic accidents in last five-year period compared to the drivers of control group. The alcohol consumption in driving population represents significant medical, social, economic and traffic problem. The control of driver's alcoholism, the sending of alcoholic drivers to an extra health examination for the repeated estimation of driving capability and including in therapeutic and health-educational program can present significant measure of the primary prevention of road traffic traumatism which is on the constant increase. 相似文献
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The mechanisms responsible for long-lasting, activity-dependent decreases in synaptic efficacy are not well understood. We have examined the initial steps required for the induction of long-term depression (LTD) in CA1 pyramidal cells by repetitive low frequency (1 Hz) synaptic stimulation. This form of LTD was synapse specific, was saturable, and required activation of post-synaptic NMDA receptors. Loading CA1 cells with the Ca2+ chelator BAPTA prevented LTD, whereas lowering extracellular Ca2+ resulted in the induction of LTD by stimulation that previously elicited long-term potentiation. Following LTD, synaptic strength could be increased to its original maximal level, indicating that LTD is reversible and not due to deterioration of individual synapses. Induction of homosynaptic LTD therefore requires an NMDA receptor-dependent change in postsynaptic Ca2+ which may be distinct from that required for long-term potentiation. 相似文献