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951.
Józefowicz-Korczyńska M Łukomski M Starska K Rózalska M 《Medycyna do?wiadczalna i mikrobiologia》2000,52(4):397-403
Finding of the a etiologic factors and participation of bacteria flora in wound healing in laryngeal cancer treatment was the purpose of our study. Investigations were performed in 27 patients. Swabs were taken from the postoperative wounds. Detailed identifications of the bacteria flora and antibiotic susceptibility of bacteria were performed. Wound healing was estimated according to extension of the carcinoma, applied antibiotics, state of the oral cavity, the kind of bacteriological flora isolated after surgical treatment from postoperative wounds. It was found that wound healing depended on the extension of carcinoma, as well as, type of isolated bacteria and antibiotic therapy used. The proper healing of postoperative wounds was not dependent on the state of the oral cavity and the dentition. The main cause of postoperative complication of wounds was methicillin-resistant Staphylococcus aureus (MRSA). 相似文献
952.
Chromatographic separation of ethanolic root extracts of Taraxacum laevigatum and Taraxacum disseminatum afforded a total of eight germacrane- and eudesmane-type sesquiterpenoids. including new compounds, 1beta,3beta,6alpha-trihydroxy-4alpha( 15)-dihydrocostic acid methyl ester and its 1-O-beta-glucopyranoside. Their structures were established by spectroscopic analyses. In addition, the structure of 4alpha(15), 11beta(13)-tetrahydroridentin B-1-O-beta-glucopyranoside was elucidated by extensive NMR studies. 相似文献
953.
From the roots of Crepis mollis, one new and two known guaianolides were isolated together with eight known guaianolide glycosides, one known germacranolide glycoside and two known phenylpropanoids. The structure and relative configuration of the new compound were established as 9alpha-hydroxy-4beta, 15, 11beta, 13-tetrahydro-dehydrozaluzanin C by spectral methods. 相似文献
954.
A molecular mechanics and molecular dynamics approach was used to examine the structure of complexes formed between the d(CGCGAATTCGCG)2 duplex and netropsin, distamycin, and four carbocyclic analogues of netropsin and distamycin (1-4). The resulting structures of the ligand-DNA model complexes and their energetics were examined. It is predicted that the compounds 1-4 should have a decreased affinity for the minor groove of AT-rich regions in comparison to netropsin and distamycin. From the energetic analysis it appears that van der Waals and electrostatic interactions are more important than specific hydrogen bonds in stabilizing the ligand-duplex complexes. We predict that compounds 1 and 2 are effectively isohelical with the DNA minor groove. The superior DNA-binding afforded by 1 and 2 in comparison to 3 and 4 results from their more effective penetration into the minor groove and smaller perturbation of molecular structure upon complex formation. 相似文献
955.
The regulation exerted by ammonium and other nitrogen sources on amino acid utilization was studied in swollen spores of Penicillium chrysogenum. Ammonium prevented the L-lysine, L-arginine and L-ornithine utilization by P. chrysogenum swollen spores seeded in complete media, but not in carbon-deficient media. Transport of L-[14C]lysine into spores incubated in presence of carbon and nitrogen sources was fully inhibited by ammonium ions (35 mM). However, in carbon-derepressed conditions (growth in absence of sugars, with amino acids as the sole carbon source) L-[14C]lysine transport was only partially inhibited. Competition experiments showed that L-lysine (1 mM) inhibits the utilization of L-arginine, and vice versa, L-arginine inhibits the L-lysine uptake. High concentrations of L-ornithine (100 mM) prevented the L-lysine and L-arginine utilization in P. chrysogenum swollen spores. In summary, ammonium seems to prevent the utilization of basic amino acids in P. chrysogenum spores by inhibiting the transport of these amino acids through their specific transport system(s), but not through the general amino acid transport system that is operative under carbon-derepression conditions. 相似文献
956.
It is generally accepted that connexin43 (Cx43) is a major constituent of heart and myometrial gap junctions. However, the presence of Cx43 gap junctions in non-pregnant myometrium is still poorly documented. Tissue sections of porcine heart and non-pregnant uterus and myometrial smooth muscle cell cultures were immunostained with monoclonal antibody against Cx43. In the heart, intensive immunostaining was confined to the intercalated discs as previously reported. In the non-pregnant uterus, punctuate immunostaining of Cx43 was seen throughout the myometrium along cell interfaces between myocytes. The expression of Cx43 was sustained in cultured smooth muscle cells isolated from non-pregnant myometrium. Western blotting has detected single isoform of Cx43 in both, cardiac and myometrial tissues. The electrophoretic mobility of porcine heart Cx43 was similar to that of myometrial isoform but different from the pattern of mobility of Cx43 of the rat heart. Hence, porcine myometrium may provide attractive model for studying cellular mechanisms triggering expression of gap junction protein in normal (non-pregnant) uterus. 相似文献
957.
To examine the role of glycineB receptors in the stimulus effects induced by psychostimulants, separate groups of rats were trained to discriminate amphetamine (AMPH; 1 mg/kg) from saline (SAL), or cocaine (COC; 10 mg/kg) from SAL, using a two-lever operant procedure. Substitution studies showed that neither 1-aminocyclopropanecarboxylic acid (ACPC; 200 mg/kg) nor 7-chloro-4-hydroxy-3-(3-phenoxy)phenyl-(H)quinolone (L-701,324; 3 mg/kg), being a partial agonist or an antagonist at glycineB receptors, respectively, generalized for the training drugs. Combination tests of glycineB ligands demonstrated that injection of a fixed dose of ACPC (200 mg/kg) or L-701,324 (3 mg/kg) together with different doses of AMPH or COC practically did not modify dose-response curves of the psychostimulants, nor did it affect their ED50 values. Our results indicate that glycineB receptors do not play a role in the discriminative effects of AMPH and COC. 相似文献
958.
The successful use of hay extract medium for growth of Verticillium marquandii in the presence of toxic black slag, resulted in selective and efficient Zn2+ recovery. An alkaline black waste slag originating from short rotary furnace, contained Zn2+ and Pb2+ (20% and 3.5%, respectively) in a form of compounds only slightly soluble in water. After 90 h of the culturing in bioreactor on hay extract medium with starch (50 g l–1) and black waste (5 g l–1) supplements, 80% of zinc and 0.5% of lead were bound by the mycelium. The pH value of the culture medium played a crucial role for limitation of the waste inhibitory effect on mycelium growth and for heavy metal recovery by the fungus. 相似文献
959.
Yildirim G Baştuğ M Akçil IE Fiçicilar H Koç E Zaloğlu N 《Biological trace element research》2000,78(1-3):7-12
The platelet-activating factor (PAF) is an inflammatory mediator and it may exert some of its effects by reactive oxygen species
(ROS). We investigated the effects of PAF and hyperbaric oxygenation (HBO) on copper (Cu) and zinc (Zn) levels in plasma and
the intracellular antioxidant enzyme activities of rats. PAF administration caused a decrease in erythrocyte catalase (CAT)
and glutathione peroxidase (GPx) activities and in the plasma zinc level. Following PAF administration, exposure to HBO also
caused a decrease in erythrocyte GPx activity. These results support the hypothesis that PAF may produce free oxygen radicals
and HBO enhances this effect. The enzyme activities of the antioxidant defense system were found to be affected by these oxidative
processes. This is likely to be the result of excessive production of ROS or overutilization and/or inhibition of the antioxidant
enzymes. 相似文献
960.