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341.
342.
Results obtained prove that respiration stimulation of mitochondria Ca2+, Sr2+, Mn2+ is determined by transport of these cations to the indicated subcellular structures with participation of Ca2(+)-uniporter. Effect of Cd2+ on respiration of mitochondria is of two-phase character. Concentration of Cd2+ being above 100 microM the stimulation phase is accompanied by the further inhibition of mitochondria respiration. La3+ inhibits respiration of mitochondria. However La3+ and Cd2+ stimulate H+ production by mitochondria, that is not blocked by ruthenium red (10 microM). Probably, the effect of La3+ and Cd2+ on respiration of mitochondria is determined by the change of proton conductivity of mitochondrion membrane. Direct inhibiting effect of Cd2+ on the respiration chain of mitochondria has been established.  相似文献   
343.
Experimental studies conducted in cooling environment assessed the features of heat exchange and thermoregulation of head during physical work varying in hardness and type. The studies determined allowable parameters of heat exchange on head (skin temperature and surface heat outflow), which are necessary for construction and evaluation of headgear. The article presents correlations between main heat-proof parameters of headgear (total heat resistance, thickness of materials and their permeability to air). The data of experimental and industrial trials helped to elaborate physiologic and hygienic requirements for heat-proof headgear in various climate conditions.  相似文献   
344.
The effects of daily intraperitoneal injections of alpha-tocopherol (30 mg/kg per day) and synthetic antioxidant IHFAN-30 (30 mg/day) in rats were compared during low-level ionizing radiation (10 days, dose rate 5 mGy/h, total dose 1.2 Gy). There were analysed: (1) amplitude of population spike of hippocampal slices; (2) endogenous phosphorylation in vitro of hippocampal synaptic proteins in the presence of cAMP; (3) formation, manifestation and reduction of food-procuring reflex. The findings showed that antioxidants made some correction of the functional state of hippocampal slices and cAMP-dependent phosphorylation system activity in brain cells from irradiated animals. No influence on training and memory functions was detected.  相似文献   
345.
Antiproteinuria effects of angiotensin-converting enzyme (ACE) inhibitors was studied in 23 patients with chronic nephritis (CN) and 32 patients with diabetic nephropathy (DN). CN patients received Capoten, DN patients were given enalapril. The drugs were also examined for the action on systemic arterial pressure, renal function and intrarenal hemodynamics. Significantly decreased urinary excretion of protein occurred in DN patients on the treatment month 1, in CN subjects on month 3. In both groups ACE inhibitors produced marked hypotensive effect, did not affect renal function, noticeably improved intraglomerular hemodynamics. Hypotensive and antiproteinuria activity of the drugs were unrelated. The mechanism of antiproteinuria action of ACE inhibitors works via normalization of intrarenal hemodynamics. Systemic arterial hypertension seems to be an additional factor aggravating disturbances of intrarenal circulation and provoking proteinuria.  相似文献   
346.
The extinction coefficient at 280 nm of the solution (pH 7,2-7,4) of thyroglobulin from normal thyroid and nodular euthyroid goiter was measured with the values of 0,6-0,7 to 0,9 ml.mg-1.cm-1. The value of E1%280 as function of the iodoamino acid content depends on the morphological state of the thyroid gland. A simple method for determination of the E1%280 value by measuring of the protein absorption spectrum is proposed.  相似文献   
347.
Previous studies found that regular confinement of dogs in an experimental environment preceding onset of an avoidance task was associated with increases in blood pressure and decreases in heart rate and respiration rate that were not prevented by adrenergic antagonists. The present study investigated a) whether divergent changes in blood pressure and heart rate also occur in micropigs preceding onset of an avoidance task, and b) the nature of changes in blood gases, plasma pH, plasma bicarbonate, hematocrit, and plasma electrolytes observed under these conditions. Blood pressure increased and heart rate decreased during 2-h preavoidance periods, whereas both blood pressure and heart rate were elevated during 20-min avoidance periods. During preavoidance periods, pO2, plasma pH, and plasma potassium pCO2 were decreased below home kennel levels during early preavoidance, whereas pCO2 and plasma bicarbonate were persistently increased and hematocrit was persistently decreased for the duration of the preavoidance periods. Each of these changes was reversed during the avoidance sessions. These findings suggest that behaviorally induced hypercapnia might participate in blood pressure regulation via increased renal sodium/hydrogen exchange and renal sodium retention.  相似文献   
348.
Data on the allelic polymorphism at the hypervariable locus 3' to the apolipoprotein B gene (apo B) in seven Turkic and Finno-Ugric human populations of the Volga-Ural region obtained by means of PCR method are presented. Sixteen allelic variants were distinguished, and the frequency distribution of alleles and genotypes across the populations studied were estimated. Alleles 34 and 36 appeared to be more common (from 13 to 45% in different populations); the calculated heterozygosity indices ranged from 59.3 to 73.4%. Comparison of the data with that on other world populations made it possible to deduce some specific features of the alleles frequency distribution associated with geographic position of the population.  相似文献   
349.
We describe an adaptation of competitive RT-PCR to quantitate rat IFN-gamma mRNA expression. An IFN-gamma DNA mimic that shared the same primers and had an identical sequence to the target mRNA except for deletion of 66 nucleotides was created by a simple PCR amplification from target cDNA. To reduce variations of initial RNA concentrations, beta-actin cDNAs from each target RNA sample were normalized using the densitometric data. A known amount of pretitrated DNA competitor was then used to analyze the relative levels of target cDNA in different samples by PCR co-amplification. The amplification efficiency for both target and competitor remained constant throughout the PCR reaction, and the ratio of target to competitor PCR product remained proportional to the initial ratio of target to competitor. Relative mRNA levels among samples determined by this method were comparable to levels determined by northern blot analysis. They were also comparable to levels of IFN-gamma protein estimated by ELISA. We conclude that this method can be used to estimate the relative abundance of the target mRNA. This method is adaptable to quantitation of other cytokines and is particularly valuable if there are numerous samples or if the amount of initial mRNA is limited.  相似文献   
350.
Benzo[a]pyrene (BaP) was dissolved in glyceryl trioctanoate, heated in a glass reaction vessel within temperature range 297.95–361.85 K with heating rate of 1 K/min and simultaneously exposed to UV light at wavelength λ = 365 nm at radiation power 20 mW cm?2 in order to study the decrease of BaP concentration due to its photooxidation. The concentration of BaP was determined by HPLC-FD periodically in 5 min intervals. As observed, the BaP concentration decreased from 62.2 μg L-1 to 19.8 μg L-1. From the experimental results, the parameters characterizing the non-isothermal kinetics of BaP photooxidation have been obtained. The parameters were tested at two various isothermal conditions (290.16 and 323.26 K) to verify a suitability of derived parameters. Comparing calculated and measured data of half-lives of BaP decrease at mentioned temperatures it was found that calculated half-lives are in a good accordance with those experimentally obtained values, when relative standard deviations at 290.16 K were 17.0% and 5.4% at 323.26 K, respectively. The kinetic parameters enable the calculation of the rate constant for any temperature in isothermal regime and make possible to model, in general, the kinetics of such processes without a deeper insight into their mechanisms.  相似文献   
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