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81.
The paper presents the results of examining 45 persons with sequels of shoulder joint injuries, by applying magnetic resonance imaging (MRI) (100%) and arthroscopy (95.6%). The data of arthroscopy were compared with those of MRI; thereafter the sensitivity, specificity, and accuracy of MRI were calculated. The findings suggested that there was no statistically significant difference in the capacities of the two comparable techniques MRI and arthroscopy to diagnose labral tears with degenerative changes, synovitis, bursitis and tendinitis (McNemar's test; p > 0.05). The capacities of MRI are greater than those of arthroscopy only to detect the structural disintegrity of the joint shoulder.  相似文献   
82.
This paper deals with the results of ultrasound (US) and multislice computed tomography (MSCT) in patients with perforated duodenal ulcer in different periods after the onset of the disease, with varying clinical manifestations, and in the postoperative period. A comparative analysis of the results of radiation studies has indicated that X-ray study is a basic technique that defines treatment policy in the early development periods of perforation; US study (USS) reveals a change in the duodenum, fluid and infiltration outside the duodenum. As circumscribed peritonitis progresses, USS allows the diagnosis of abdominal abscesses and infiltrations. Out of the radiation techniques, MSCT is of most importance in the diagnosis of interintestinal abscesses and in the determination of syntopy of purulent cavities.  相似文献   
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Microbiology - Resistance to biodegradation, which is among the most advantageous features of synthetic polymers, is also the reason for their accumulation in the environment and therefore...  相似文献   
86.
A constitutively expressed thermoactive amidase from the thermophilic actinomycete Pseudonocardia thermophila was purified to homogeneity by applying hydrophobic interaction, anion exchange and gel filtration chromatography, giving a yield of 26% and a specific activity of 19.5 units mg–1. The purified enzyme has an estimated molecular mass of 108 kDa and an isoelectric point of 4.2. The amidase is active at a broad pH range (pH 4–9) and temperature range (40–80°C) and has a half-life of 1.2 h at 70°C. Inhibition of enzyme activity was observed in the presence of metal ions, such as Co2+, Hg2+, Cu2+, Ni2+, and thiol reagents. The amidase has a broad substrate spectrum, including aliphatic, aromatic and amino acid amides. The presence of a double bond or a methyl group near the carboxamide group of aliphatic and amino acid amides enhances the enzymatic activity. Among aromatic amides with substitutions at the o-, m-, or p-position, the p-substituted amides are the preferred substrates. The highest acyl transferase activity was detected with hexanoamide, isobutyramide and propionamide. The Km values for propionamide, methacrylamide, benzamide and 2-phenylpropionamide are 7.4, 9.2, 4.9 and 0.9 mM, respectively. The amidase is highly S-stereoselective for 2-phenylpropionamide; and the racemic amide was converted to the corresponding S-acid with an enantiomeric excess of >95% at 50% conversion of the substrate. In contrast, the d,l-tryptophanamide and d,l-methioninamide were converted to the corresponding d,l-acids at the same rate. This thermostable enzyme represents the first reported amidase from a thermophilic actinomycete.  相似文献   
87.
It is revealed that restriction of protein in nutrition of rat pups in early ontogenesis, at the period of transition from the mixed to the definitive nutrition, produces change of structural parameters and functioning of digestive enzymes in various parts of small intestine (duodenum, jejunum, and ileum) and in large intestine as well as of these hydrolases in liver and kidney in adult life. The disturbance of quality of nutrition in early ontogenesis seems to affect negatively digestive functions of small intestine and trophic-barrier function of large intestine, liver, and kidney, which can promote development of diseases not only of the gastrointestinal tract, but also of other organs.  相似文献   
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A study was made of the effect of ionizing radiation (0.013 C/kg) on Na, K- and Ca, Mg-ATPase activity in membranes of rat organs differing in radiosensitivity. It was shown that radiation mainly caused activation of enzymes that was most pronounced in brain membranes.  相似文献   
90.
The action of ATP/ADP-antiporter inhibitors upon the uncoupling effect of palmitate, detergents and 'classical' uncouplers has been studied. The uncoupling effect was estimated by stimulation of succinate oxidation and of H+ permeability of rat liver mitochondria in the presence of oligomycin. It is shown that carboxyatractylate (CAtr) and pyridoxal 5-phosphate (PLP) suppress the uncoupling induced by palmitate and the anionic detergents SDS and cholate, but do not affect that induced by the cationic detergents CTAB, by the non-ionic detergent Triton X-100, as well as by the 'classical' uncouplers FCCP and DNP. The results are discussed in terms of a concept assuming that the ATP/ADP-antiporter facilitates the electrophoretic export of hydrophobic anions from mitochondria.  相似文献   
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