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81.
A microorganism capable of degrading DL-mandelic acid was isolated from sewage sediment of enrichment culture and was identified as Pseudomonas convexa. It was found to metabolize mandelic acid by a new pathway involving 4-hydroxymandelic acid, 4-hydroxybenzaldehyde, 4-hydroxybenzoic acid, and 3,4-dihydroxybenzoic acid as aromatic intermediates. All the enzymes of the pathway were demonstrated in cell-free extracts. L-Mandelate-4-hydroxylase, a soluble enzyme, requires tetrahydropteridine, nicotinamide adenine dinucleotide phosphate, reduced form, and Fe2+ for its activity. The next enzyme, L-4-hydroxymandelate oxidase (decarboxylating), a particulate enzyme, requires flavine adenine dinucleotide and Mn2+ for its activity. A nicotinamide adenine dinucleotide-dependent, as well as a nicotinamide adenine dinucleotide phosphate-dependent, benzaldehyde dehydrogenase has been resolved and partially purified. 相似文献
82.
HM Agrama JM Blackwood CS Brown GW Machiedo BF Rush 《Canadian Metallurgical Quarterly》1976,132(3):418-421
Various types of drains were inserted into the peritoneal cavity of twenty-eight dogs. After one to seven days, all drains failed to show the presence of 200 cc of colored fluid injected intraperitoneally. On autopsy, all tubes were surrounded and occluded by omentum. 相似文献
83.
1 Ephedrine plasma levels have been measured in ten asthmatic patients given a singel dose of ephedrine hydrochloride (22 mg) along and in combination with theophylline and a barbiturate. 2 Pharmacokinetic assessment of the data indicated no significant intra-subject changes in kinetic parameters before or after chronic treatment with ephedrine HCl (11 mg three times a day) alone or in combination. 3 Tolerance to these therapeutic doses, if it occurs, is therefore not disposition-related but rather to pharmacodynamic changes. 相似文献
84.
Mouse dorsal, ear, tail and foot epidermis are compared according to their tissue architecture and cell kinetics. Cell proliferation is expected in terms of the daily volume of keratin replaced. The stratum corneum may be organized into vertical columns of squames, which may have minimal overlap as in dorsum and ear, or maximal overlap as in tail. Individual areas are adapted to their function both in squame fine structure and rate of cell replacement. The surface keratin loss/replacement rate is at its highest in foot and tail, and lowest in ear and dorsum. Observations on hairless mouse dorsum are also included. 相似文献
85.
86.
A generalized correlation for saturated liquid densities of pure compounds, based on the Guggenheim equation, has been extended for applications to mixtures. The method employs a mole-average acentric factor and scaling volume, and a weighted average critical temperature for the mixture. The method was tested on twenty-four binary and two ternary systems comprising hydrocarbons and non-hydrocarbons. Overall average absolute deviation in predicted densities is less than two percent for a total of 1,096 data points. 相似文献
87.
P Katsikis G Harris T Page E Paleolog M Feldman MR Dalesandro CS Kinney SA Siegel JN Woody PE Daddona 《Canadian Metallurgical Quarterly》1993,5(4):348-353
When the projecting point of saphenous nerve in second somatosensory cortex (S II) of cat was stimulated, the evoked potentials elicited by C-fiber inputs of saphenous nerve recorded in the primary somatosensory cortex (C-CEP) might be either inhibited or facilited according to whether the superficial and/or the deeper layer of the cortex was stimulated. The inhibition was expressed as a decrease of amplitude and prolongation of latency of C-CEP; while the facilitation, as an increase of amplitude and duration of C-CEP. When the superfaicial layer of S II was stimulated by weaker current, both inhibitory and facilitatory effects could be observed, but only inhibitory effect was observed, when the deep layer was stimulated. With the same intensity of stimulation, inhibitory effect was more pronounced when the deep layer rather than the superficial layer was stimulated. It is suggested that S II may play a role in the modulation of C-CEP of S I. 相似文献
88.
Coronary vasodilator and hemodynamic profiles of JTV-506, a newly synthesized 2,2-bis-methoxymethyl benzopyran-derivative potassium channel opener, were evaluated in conscious dogs. JTV-506 (2.5-10 microg/kg, i.v.) elicited dose-dependent increases in coronary blood flow (CBF) and heart rate (HR) but only slight changes in mean blood pressure (MBP). Other vasodilators such as levcromakalim, nicorandil, diltiazem, and nitroglycerin, when administered intravenously, elicited increases in CBF and HR and a decrease in MBP. When dosed orally JTV-506 (0.01-0.1 mg/kg), levcromakalim (0.01-0.1 mg/kg), nicorandil (1-10 mg/kg), and nifedipine (3-30 mg/kg) also elicited increases in CBF and HR and a decrease in MBP. JTV-506 caused a marked increase in CBF with slight changes in HR and MBP. In contrast to JTV-506, however, the changes caused by levcromakalim, nicorandil, and nifedipine were accompanied by a marked increase in HR and a marked decrease in MBP. These results suggest that the action of JTV-506 on hemodynamics is different from that of other vasodilators, including reference potassium channel openers, and that the profile of cardiovascular action of JTV-506 may be useful in the treatment of angina pectoris. 相似文献
89.
CL Franklin CS Beckwith RS Livingston LK Riley SV Gibson CL Besch-Williford RR Hook 《Canadian Metallurgical Quarterly》1996,34(12):2952-2958
A filamentous, gram-negative, motile bacterium with a single polar sheathed flagellum was isolated from gallbladders of hamsters with cholangiofibrosis and centrilobular pancreatitis. Bacteria grew under microaerophilic conditions at 37 and 42 degrees C, were oxidase, catalase, arginine aminopeptidase, and L-arginine arylamidase positive, reduced nitrate to nitrite, were resistant to cephalothin, and exhibited intermediate susceptibility to nalidixic acid. Sequence analysis of the 16S rRNA gene indicated that the bacterium was a novel member of the Helicobacter genus, most closely related to Helicobacter pametensis. We propose to name this bacterium Helicobacter cholecystus. In epidemiologic studies, isolation of H. cholecystus correlated strongly with the presence of cholangiofibrosis and centrilobular pancreatitis; however, further studies are needed to define the role of this bacterium in pathogenesis. 相似文献
90.
OBJECTIVE: The aims of this investigation were to measure corticotropin-releasing hormone (CRH), corticotropin (ACTH) and cortisol before, during and after delivery searching for an endocrine intercorrelation of the hypothalamic-pituitary-adrenal (HPA) axis and to correlate these findings with obstetrical variables. METHODS: Blood was sampled from 50 women with singleton pregnancies at term without uterine contractions, during delivery (after full cervical dilatation) and on the 4th postnatal day. Hormones were measured by radioimmunoassay (RIA). The correlation between obstetric variables, sociodemographic and endocrine data were evaluated using the Spearman rank coefficient. Group comparisons for continuous variables were calculated using the Mann-Whitney U test and Kruskal-Wallis test. RESULTS: Maternal plasma ACTH and cortisol increased significantly during labor, declining toward the 4th postnatal day (p < 0.001) and showing a significant intercorrelation (p < 0.01). Compared to women without uterine contractions CRH rose during labor (p < 0.05) and decreased rapidly to the 4th postnatal day (p < 0.001). No correlations between CRH and ACTH or cortisol were observed. None of the obstetrical variables (parity, newborn's weight, duration of delivery) revealed any significant correlation with ACTH. Analgetic medication (pethidine hydrochloride) was not able to influence the endocrine response to labor stress. CONCLUSIONS: Stressful experience during childbirth has an impact on endocrine response. However, this is not fully evident along the HPA axis in a simple biological model with monocausal dependencies. This 'biological stress model' is not sensitive enough to detect different childbirth conditions and the hormones in the maternal compartment have partially fetal (placental) origin. 相似文献