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Effects of copper laser stimulating doses on biochemical parameters of competent chicken embryo myoblast and neuroblast cultures were studied. It was shown that in both systems biostimulation was characterized by an increase of water-extractable protein level and a considerable rise of total and specific creatine kinase activity. The authors believe that cases of protein drop during myoblast culture exposure to chemical agents described in literature were caused by these agents overdosage and that this drop may be considered as a manifestation of a peculiar biochemical shock induced by overdosage. They suggest to follow up the time course of water-extractable protein levels in the cultures to differentiate between trophic and injurious loading.  相似文献   
486.
38 patients with ischemic heart disease (IHD) and sick sinus syndrome (SSS) received combined therapy with nifedipine (Corinfar-Retard) and talinolol (Cordanum). The former drug had a positive chronotropic effect on the heart, the latter's chronotropic effect was slightly negative. All the patients had sinus bradycardia and ectopic arrhythmia which needed therapeutic correction: supraventricular and ventricular extrasystoles, fibrillation paroxysms or/and atrial flutter, paroxysmal supraventricular tachycardia, ventricular tachycardia. Cordanum was given in a dose 50 mg twice a day, Corinfar-Retard 20 mg twice a day for 16 days. 30 patients responded to the treatment. In addition to good subjective response, episodes of extrasystoles, paroxysms, flutter and fibrillation occurred much less frequently. Side effects resulted in the treatment discontinuation in 3 patients.  相似文献   
487.
The influence of food fibres and plant proteins on microorganisms, bacteriophages, antibiotics and penicillinase was studied in vitro. It was shown that pectin was the only agent that had a bactericidal effect on the most widely distributed pathogenic and opportunistic microorganisms and did not influence indigenic microflora. High concentrations of pectin (> 2 per cent) had an inactivating effect on therapeutic bacteriophages. There was also a decrease in the antimicrobial activity of penicillins. The other agents tested i.e. wheat bran, soya isolate and soybean flour had no influence on microorganisms, bacteriophages and antibiotics. No sorption activity of the food fibres and plant proteins with respect to microorganisms and antibiotics or their effect on penicillinase was observed.  相似文献   
488.
We studied the microbial changes on fresh (still warm) pork carcasses immediately after electrostatic spraying of lactic acid solutions and during chilled storage. Lactic acid decontamination (LAD) included electrostatic spraying of hot (55C) solutions of 1% lactic acid for 90 s and 2%- and 5% lactic acid for 30 and 90 s. The treatments increased the carcass surface temperature from 22C to about 32–43C. The bactericidal activity of lactic acid killed mainly Gram-negative bacteria. Reductions in "total" psychrotrophic Gram-negative and Entero-bacteriaceae counts were found reliable indicators for the efficacy of LAD. Hot 2–5% LAD treatments achieved overall reductions in Gram-negative psychrotrophs ranging from 0.8 to more than 1.4 log10 cfu per cm2. Overall reductions in mesophilic Enterobacteriaceae counts ranged from approximately 1.2 to more than 1.8 log10 cfu per cm2. Treatments with 1% lactic acid achieved marginal 0.5–0.6 overall log10 reductions in these groups of organisms. Bactericidal effects after LAD occurred during a lag period of whose duration increased with the lactic acid concentration of the spray solution. The lag lasted less than 1 day on 1% LAD, 2 days on 2% LAD and 4 days on 5% LAD meat. During these lags the meat surface pH rose from pH 2.7 to 3.2 immediately after LAD to pH 4.8 to 5.2. During aerobic chilled storage after LAD the growth of Gram-negative psychrotrophs was controlled only temporarily. These organisms became the dominant group of organisms. The practical utility of electrostatic spraying of fresh pork carcasses with hot 1–5% LAD to improve the keeping quality is questionable .  相似文献   
489.
The cytopathogenic action of P. mallei on macrophages of golden hamsters and transplantable Hep-2 cell culture was studied. It was shown that the culture test systems may be efficient in estimation of the P. mallei virulent properties. The effect of antibacterial drugs on intracellular P. mallei was also studied.  相似文献   
490.
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