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1.
The expression of a Helicobacter pylori colony in an asymptomatic carrier of the infection is found to vary significantly with time in the absence of pharmacological treatment. Characteristics of the bacteria expression in different subjects are shown using the chromatographic mass spectrometric 13C urease breath test.  相似文献   
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Amyloid oligomers, protofibrils, and fibrils of various amyloidogenic proteins are known to induce cell death. Tetracycline prevents the formation of fibrils of Aβ peptide and other amyloidogenic proteins and decomposes mature fibrils. It was previously shown that sarcomeric cytoskeletal proteins of the titin family (protein X, protein C, and protein H) in vitro form amyloid fibrils and tetracycline decomposes them. In this work, the concentration and time dependence of the survival of polymorphonuclear leukocytes in the presence of protein X amyloid fibrils is demonstrated. It is also shown that the survival rate increases as fibrils are decomposed by tetracycline. The antibiotic itself is found to be nontoxic. The results obtained show that this approach can be used to evaluate the efficiency of drugs that prevent or rectify amyloidoses.  相似文献   
4.
The effect of the liposomal form formed by taxifolin and metals of variable valency was investigated. It was shown that the application of preparations based on the free flavonoid and its complexes with Fe(II/III) and Cu(II) ions after chemical burns results in a more effective skin regeneration and the repair of hair follicles and sebaceous glands. A tendency for a more effective wound healing after the applications of taxifolin-Cu(II) and taxifolin-Fe(III) liposomal complexes versus control was observed. It was assumed that the mechanism of action of these preparations is based on the oxidative polymerization and conjugation of the flavonoid, which results in the utilization of toxic metabolites and lipid peroxidation products.  相似文献   
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Taxonoprint (a modification of DNA restrictase analysis) allows to distinguish sympatric species, that do not mate or produce hybrid offspring that are sterile or not viable. It is shown that taxonoprints of whitefish are very similar of identical. Sympatric whitefish are continuing to be separate despite they easily mate in experiments and in nature (up to 30% of individuals in nature are hybrids) and hybrids offspring have some features of heterosis. However it appears that hybrids of the second generation are not viable and can exist only because of back crossing with parents. In allows to keep a species independence in the process of gene exchange and to use heterosis of the first generation. Similar isolation mechanism is determined for other fish families (Acipensepidae, Clupeidae, Cyprinidae, Percidae) and some mammals (camels, sheep, bulls).  相似文献   
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The beta-lactamase activity of staphylococci isolated from the nasopharynx and skin of children with destructive affections of the lungs and from blood of patients with cardiovascular diseases subjected to surgical operations was determined with acidometric and microbiological procedures. Interrelation between synthesis of beta-lactamase by the staphylococcal strains and their resistance to beta-lactam antibiotics was demonstrated. No correlation of the antibiotic resistance and the taxonomic position of the staphylococcal strains was observed.  相似文献   
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Repeated (over 7 days) intranasal introduction of the Pro-Gly-Pro-Leu peptide into animals at a dose of 1 mg/kg before injection of the diabetogenic metabolite alloxan provided effective protection of an organism against development of insulin-dependent diabetes mellitus and prevented development of hyper-coagulating alterations in the system of hemostasis. An increasing in the anticoagulating and fibrinolytic activities in rat blood plasma was detected. The peptide under study also showed antidiabetogenic action: repeated intranasal introduction of the Pro-Gly-Pro-Leu peptide into animals for 7 days inhibited development of diabetes symptoms in rats pretreated with alloxan.  相似文献   
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A 25-year-old previously asymptomatic pregnant woman at 36 weeks'' gestation was noticed to have repetitive monomorphic ventricular tachycardia. A dilated left ventricle with moderately reduced systolic function was found on echocardiographic examination. This is a very rare presentation of peripartum cardiomyopathy (PPCMP) presenting with repetitive monomorphic ventricular tachycardia.  相似文献   
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The effect of neurotensin on submaximally-stimulated hepatobiliary and pancreatic secretion was studied in 6 healthy subjects. An intravenous infusion of neurotensin 1.4 ± 0.3 pmol/kg/min, designed to reproduce plasma neurotensin immunoreactivity levels within the physiological range, produced a significant increase in pancreatic bicarbonate output. Plasma concentrations of pancreatic polypeptide rose by 83 ± 16 pmol/l and were associated with a small reduction in trypsin, but no significant change in bilirubin outputs.  相似文献   
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The influence of a low dose (1 microM, 2 microl) of nonselective agonist of cannabinoid CB1 receptor WIN 55.212-2 on seizure activity in different brain structures was investigated in waking guinea pigs. Changes in spontaneous local field potentials and seizure afterdischarges evoked by the electrical stimulation of the perforant path were recorded simultaneously in the hippocampus, entorhinal cortex, medial septal region, and amygdala after a preliminary intraventricular injection of WIN 55.212-2. It was found that WIN 55.212-2 blocked the stimulation-elicited seizures in 80% of tests. A repeated injection of the agonist within 30 days caused an increase in the amplitude of local field potentials and the power of the theta rhythm in all the structures under study. The infusion of kainic acid provoked the onset of status epilepticus in control animals, whereas guinea pigs injected with the agonist (daily, during 25-30 days) did not develop the status. Possible mechanisms of the protective influence of WIN 55.212-2 are discussed.  相似文献   
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