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61.
The activity of 63 neurones of the dorsal hippocampus field CA1 was studied in unrestrained rabbits in different behaviour and in the course of repetitive afferent stimulation. It has been found that changes in the mean frequency of spontaneous activity of most neurones (90%) correlate with the kind of the animal's behaviour. Replacement of calm alertness by an active state is primarily attended with enhanced mean frequency of firing. Two types of response dynamics to a repetitive stimulation were revealed: 1) successive decrease of reaction and 2) gradual augmentation and subsequent drop. As stimulation went on most of the neurones revealed a change in the nature of responses: diffuse phasic and tonic reactions were replaced by structured responses of a specific type. The data obtained are regarded as proof of the hippocampus involvement in the organization of integrated orienting behaviour.  相似文献   
62.
Diffuse myocarditis with alteation and proliferation was described in adult BALB/c mice infected with Coxsacke A13 virus. A marked tendency to sclerotic processes 30 to 60 days after the infection was noted; this can underly the reduction of the functional activity of the myocardium and lead to the development of cardiomyopathy.  相似文献   
63.
It was investigated the influence of food diet supplements with chromium on dynamic of glycaemia, lipid profile, blood pressure and weight in type 2 diabetic patients. Traditional hypocaloric diet was supplemented with chromium-spirulina (50 mcg chromium per day). The results investigations indicated that a chromium-enriched diet has beneficial effects on basal and postprandial glycaemia, the content of cholesterol and triglycerides in serum in compared with a traditional hypocaloric diet.  相似文献   
64.
The antioxidant properties of the carotenoid lycopene were compared in three different model oxidative systems. In egg yolk liposomes, in the presence of 2.5 mM FeSO4 and 200 mM ascorbate, lycopene, alpha-tocopherol, and beta-carotene inhibited the accumulation of lipid peroxidation products reacting with 2-thiobarbituric acid (TBARS) in a dose-dependent mode, with the concentration of half-inhibition being 80, 30 and 130 mM, respectively. In the liposomes subjected to illumination with a He-Ne laser (632.8 nm) at a dose of 10.5 J/cm2, in the presence of 32.5 micrograms/ml hematoporphyrin derivatives (Fotogem, NIOPIC, Russia) TBARS accumulated, and this effect was inhibited by lycopene, alpha-tocopherol, and dihydroquercetin with approximately equal efficiencies (the half-inhibition concentrations were 10(-5) mM). In both systems studied, sodium azide at a concentration of 10 mM inhibited the TBARS accumulation by no more than 20%. Apparently, the inhibitory action of not only alpha-tocopherol, but also beta-carotene and lycopene was the result of their antiradical action, rather than quenching of the singlet oxygen in an aqueous medium. The introduction of lycopene, as well as beta-carotene in liposomes subjected to Fe(2+)-induced lipid peroxidation decreased the chemiluminescence (CL) intensity at the stage of CL slow flash, with no essential influence on the lag period. These data suggest that the effect of lycopene on lipid peroxidation was the result of its interaction with free radicals rather than chelating ferrous ions. The antiradical activity of lycopene was also confirmed by the method of luminol photochemiluminescence (PCL). Lycopene increased the PCL lag period (L) and decreased the PCL amplitude (A), which implies its antiradical and SOD-like activity in this system.  相似文献   
65.
66.
Chronic cystitis (CC) in females is annually encountered now in 15,000-20,000 per 1,000,000. Etiological and pathogenetic factors in CC are closely related. Bacteriologically, CC is represented primarily by Enterobacter. The infection, as a rule, ascends the lower urinary tracts. The contributing factors are: weak local antibacterial mechanisms of the urogenital system, anatomical variants and anomalies of the urethra and introitus, sexual activity, impaired urodynamics of the lower urinary tracts. The diagnosis of chronic inflammation of the bladder is made mainly endoscopically, with obligatory endovesical multifocal biopsy of the bladder followed by histological examination. The treatment of CC includes antibacterial, general and local antiinflammatory therapy, measures to normalize urodynamics of the lower urinary tracts, correction of hygienic and sexual factors, immunostimulation. 16 nonresponders to conservative treatment of interstitial cystitis with progressive contraction of the bladder were subjected to supratrigonal or subtotal resection of the bladder with one-stage ileocystoplasty.  相似文献   
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68.
An experimental method of laser heating making it possible to simulate the first crisis of heat emission from fuel element cladding with pulsed energy input into the fuel core is described. The results of experiments for stationary saturated coolant (water) at atmospheric pressure are presented. A model of boiling under pulsed heating that makes it possible to calculate the dynamics of heat emission at the stage before onset of crisis is presented. The predictions of the model agree with the experimental data.  相似文献   
69.
BACKGROUND: Both dermabrasion and high-energy pulsed carbon dioxide (CO2) laser resurfacing can improve the appearance of surgical scars. Although the results of these two procedures have been compared using historical data, a prospective evaluation has never been performed in humans. OBJECTIVE: To prospectively compare the clinical effects of dermabrasion and high-energy pulsed CO2 laser resurfacing in the revision of surgical scars. METHODS: Facial surgical scars in four patients were prospectively revised using a split scar model. One half of the scar was dermabraded and the other half was resurfaced with the high-energy pulsed CO2 laser. Comparisons of the two treatment modalities were performed through clinical assessment, photographic evaluation, and textural analysis of the scars. RESULTS: The high-energy pulsed CO2 laser-resurfaced halves of the scar were bloodless with less postoperative crusting in comparison with the dermabraded halves. Reepithelialization time and degree and duration of postoperative erythema were similar for both treatment halves. Photographic evaluation and textural analysis showed comparable improvement in the clinical appearance and surface texture of the scars with both treatment modalities. CONCLUSIONS: Both the high-energy pulsed CO2 laser and dermabrasion can achieve comparable clinical improvement in the revision of surgical scars. The high-energy pulsed CO2 laser offers the advantage of a bloodless field and a more precise method of tissue ablation. Postoperative erythema, however, is an expected finding with both treatment modalities.  相似文献   
70.
The influence of serotonin adipinate on the mechanisms of development of tissue hypoxia, disturbances of the microcirculatory bed and smooth muscles before, during and after operative interventions was studied in experiments and clinical practice. The syndrome of serotonin insufficiency is described including smooth muscle insufficiency which can be abolished by serotonin adipinate administered at the early postoperative period irrespective of the cause of surgery, age and sex of the patient. Good results were obtained in treatment of patients after operations on the liver, pancrease, heart, in patients with the diabetic foot and in other diseases. No complications or lethal outcomes resulting from using serotonin adipinate were noted.  相似文献   
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