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251.
Populations of Arabidopsis thaliana (L.) Heynh., and Pinus sylvestris L., growing within 30 km of Chernobyl and Bryansk region have been analyzed for the frequency of embryonic lethal mutations on Arabidopsis and frequency of chlorophyll mutations and chromosome aberrations by pine. On pine also have been analyzed rate of mutations at enzyme loci in endosperms of seeds. Dose dependence of the value genetic damage on level of radioactive pollution was observed.  相似文献   
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Parts of katG and rpoB from 27 Russian Mycobacterium tuberculosis isolates were sequenced to detect mutations causing resistance to isoniazid (INH) and rifampin (RMP), respectively. All 24 INH-resistant isolates had a mutated katG, and 22 of them (91.7%) carried a mutation coding for a Ser315Thr shift. An rpoB mutation was noted for each of the 21 RMP-resistant isolates, with Ser531Leu being the most prevalent change encoded. Only two isolates had identical IS6110 fingerprints.  相似文献   
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Adjuvant use of enterosorbents in combined therapy of gastroduodenal ulcers (158 patients), nonspecific ulcerative colitis with intestinal dysbacteriosis was assessed. Enterosorption in combined therapy of gastrointestinal diseases with dysbacteriosis potentiated positive effect. The highest benefit of enterosorption occurs in intestinal affections (nonspecific ulcerative colitis, irritable bowel-syndrome, chronic enteritis, colitis). In gastroduodenal ulcer lignin sorbent (polyfepan) is preferable. Polyfepan acted positively on intestinal dysbacteriosis through eliminating Escherichia with hemolyzing properties and enterococci, by reducing lack of bifidobacteria.  相似文献   
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A 5-year-old girl with an asymptomatic posterior mediastinal cyst from birth was followed with repeated echocardiograms. The cyst developed communication with the bronchus spontaneously around 8 months of age without clinical symptoms. This was detected from the sudden disappearance of the mass on echocardiogram, and an unusual air-pocket on chest roentgenogram. Computed tomography (CT) of the chest confirmed the diagnosis of communicating bronchogenic cyst (BC). She was treated successfully with complete surgical excision of the cyst and closure of the defect in the bronchus. We emphasize that surgery is indicated in all mediastinal BCs because of potential complications.  相似文献   
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Exposure to a brief, stressful event is reported to facilitate classical eyeblink conditioning in the male rat (Rattus norvegicus) by use of a delay paradigm in which the conditioned stimulus (CS) and unconditioned stimulus (US) overlap and coterminate. This study examined the effects of stress on trace conditioning, a task in which the CS and US were separated by 500 ms. Experiment 1 showed that exposure to brief (1 s), low-intensity (1 mA) tailshocks facilitated acquisition 24 hr later. Experiment 2 showed that stressor exposure did not affect retention or extinction of trace conditioning in rats that were stressed after acquisition. Experiment 3 showed that exposure to the same stressor opposed acquisition of inhibitory conditioning. These results suggest that exposure to a stressful event persistently facilitates acquisition of trace conditioning and enhances a bias toward acquiring positive versus negative associations.  相似文献   
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Small-flow membranous oxygenation of the blood was used in 45 patients with peritonitis in the multiple organ failure phase. In ten cases blood oxygenation was combined with hemofiltration. MOCT 19-03 (Kvant Research and Production Unit) and Gambro FH hemofilters (Sweden) were employed. Combination of small-flow membranous oxygenation of the blood combined with hemofiltration appreciably improved the oxygen-transporting function of the blood in adult patients with the respiratory distress syndrome, which was due to mutual potentiation of the two methods' effects. Small-flow membraneous oxygenation alone improved cellular immunity and decreased the laboratory manifestations of endogenous intoxication due to biotransformation of toxic products.  相似文献   
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