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11.
The effect of a novel flavonoid, venoruton (a mixture of mono-, di-, tri- and tetrahydroxyethylrutosides) has been investigated in healthy rat lenses and compared with diabetic cataract modelled in vitro. One mM venoruton was added to medium simulating healthy and diabetic conditions for the incubated lenses; damage was followed by either stereoscopic photography of the lenses under a Cooperative Cataract Research Group operating microscope or with our recently developed method: the leakage of lactate dehydrogenase (LDH) into the lens culture media. The increased LDH activity in the medium and observable development of the opacity were correlated with cell damage, which has been found to be associated with globular degeneration and cataract formation. The extent of opacification and LDH release is reduced if 1 mM venoruton is included in the medium. The protective effect may be related to antioxidant activity against reactive oxygen species: decreased luminol luminescence was shown after venoruton addition to either superoxide-generating hypoxanthine plus xanthine oxidase, or hydrogen peroxide. 相似文献
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13.
The development of porosity in the course of carbonization of a flame coal, original and pre-oxidized, was studied by means of the adsorption of benzene and carbon dioxide. The results were compared with corresponding data for cokes from a xylitic brown coal. The influence of coal oxygen content on the formation of coke porosity and its thermal dependence is discussed. 相似文献
14.
The effect of drying and atomization conditions on the physical properties of powders for agglomerate-like materials and skin-forming material are studied in this article. A neural model is used for powder bulk and tapped density predictions. 相似文献
15.
Textured milk proteins were tested in a meat model system with an exchange level of 34-87% of the meat proteins. The correlation between the substitution index and the calcium and phosphorus content was statistically significant. 相似文献
16.
Victor Chabanenko Roman Puźniak Adam Nabiałek Sergei Vasiliev Vladimir Rusakov Loh Huanqian Ritta Szymczak Henryk Szymczak Jan Jun Janusz Karpiński Vitaly Finkel 《Journal of Low Temperature Physics》2003,130(3-4):175-191
We present a study of magneto-thermal instabilities in polycrystalline MgB2 superconductor, by magnetic hysteresis loop measurements and by investigations of magnetic flux dynamics with a miniature Hall probe. Temperature and magnetic field ranges where the flux jumps may be observed have been determined. On the basis of measurements of the magnetic flux dynamics, an average magnetic diffusivity describing the process of the flux jump is estimated. This parameter is compared with the thermal and magnetic diffusivities calculated on the basis of available data for thermal conductivity, heat capacity and resistivity. It is shown that the estimated value of the field of the first flux jump is influenced significantly by the field dependence of specific heat. In order to explain the observed phenomenon, the temperature reached by the sample during the flux jump at different magnetic fields is calculated. 相似文献
17.
AK Ma?ek O Rowiński T Ostrowski L Hilgertner M Januszewicz M Szostek 《Canadian Metallurgical Quarterly》1995,50(40-44):19-22
Subclavian steal syndrome (SSS) appears when the origin of the subclavian artery (SA) is occluded or stenosed. Introduction of transcranial Doppler sonography (TCD) provided an opportunity to evaluate parameters of the blood flow in the vertebral (VA) and basilar artery (BA). Measurements of blood flow velocities performed at rest and after the brachial hyperemia test allow one to classify hemodynamic types of SSS. The aim of the study was to categorize types of steal and to compare the differences of flow patterns before and after percutaneous transluminal SA balloon angioplasty (SA-PTA). Fourty-eight patients with angiographically confirmed SSS (aged from 27 to 68 years, mean 53; 2/1 f/m ratio) were examined with 2 MHz range-gated, pulsed transcranial Doppler device (TC 2-64B EME). Both VA and BA were evaluated by the transoccipital approach at rest and during the brachial hyperemia. In 5 cases (10.4%) permanent reversal blood flow in the BA was observed (complete basilar steal). In flow in the BA blood flow was in the normal direction at rest and altered (reversed or decreased) when induced with brachial hyperemia test (transient basilar steal). In the next 14 patients (29.2%) permanently reversed VA blood flow was observed with only a slight or no alterations of the BA flow after the hyperemia test (complete vertebral steal). In the last 19 cases (39.6%) alterations of the VA blood flow without changes in BA flow were observed (latent vertebral steal). Between 1991 and 1994 twenty seven symptomatic patients with different hemodynamic types of SSS were treated with SA-PTA. TCD evaluation of VA's and BA using the hyperemia test was performed before, 3 to 7 days and 3 months after morphologically and hemodynamically successful subclavian artery balloon PTA. Normal results of vertebrobasilar examinations were obtained in 26 cases after this procedure. In one case the latent vertebral steal was detected. The 28 months mean follow-up revealed no significant changes in TCD flow patterns recorded from VA's and BA. After collecting data of about 60 patients with SSS we examined with TCD we conclude that: in patients with a hemodynamically significant SA stenosis the presence of reversed ipsilateral VA blood flow (a radiologic steal) its not a good determinant of either the presence or type of presenting symptoms and after successful PTA or recanalisation and PTA of SA in almost all cases we examined close to normal TCD recordings in BA and VA. 相似文献
18.
J Ma?olepszy J Patkowski E Liebhart M Kraus-Filarska B Panaszek A Wolańczyk-Medrala 《Canadian Metallurgical Quarterly》1993,61(3-4):107-114
Clinical study on efficiency of the nedocromil sodium (Tilade, Fisons) was performed in 20 patients with atopic and nonatopic bronchial asthma. The drug was administrated in dose of 8 mg per day for 2 months which allowed to renounce regular using of Beclocort forte after 7 days of the treatment. In both types of bronchial asthma the positive effect of nedocromil sodium was confirmed, causing increase of pulmonary ventilation and decrease of bronchial hyperactivity. Especially profitably effect was noticed in atopic bronchial asthma in which statistically important increase of peak expiratory flow (PEF) was obtained and decrease of bronchial hyperreactivity by PC20 for histamine was observed (p < 0.05). Mentioned above spirometric parameters did not differ in statistically important pattern in patients with nonatopic bronchial asthma, when Beclocort forte group with Tilade group compared. Neither important differences in general number of cells nor percentage composition of cell smears were observed in bronchoalveolar lavage fluid. 相似文献
19.
Serum and urinary activity of alpha-amylase and isoamylase salivary was assessed in 40 patients with different types of ovarian cancer. The measurements were performed before surgical procedure and the 7th day after surgical removal of the tumor. Significant increases activity was found in patients with serosal ovarian cancer p < 0.001. On the 7th day after operation the activity of alpha-amylase and her of isoenzyme salivary reached control values. 相似文献
20.
K Zó?towska J Dziekońska-Rynko H Olender Z Jab?onowski 《Canadian Metallurgical Quarterly》1995,41(4):421-428
Hybrid chickens Astra S fed vitamin A deficiency diet containing 11 or 19% protein were infected with 500 invasive eggs of Ascaridia galli. One part of them received vitamin A in a dose corresponding to daily requirement, other part in double dose. After 7 weeks the extensity and intensity of ascaridiosis were determined. In pancreas and intestinal contents the activities of alpha-amylase, lipase and trypsin were measured. The invasion index was the highest in the group of chickens fed the protein and vitamin A deficiency diet. Vitamin A in a requirement dose lowered the parasite index. The results with double dose of vitamin A were worse in comparison with single dose. The activities of digestive enzymes were lower in infected animals than in the control groups. Vitamin A acted as moderator of the enzymatic changes during ascaridiosis. 相似文献