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21.
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
22.
aneta Polkowska Jacek Namienik Jacek Czerwiski & Bogdan Zygmunt 《International Journal of Food Science & Technology》1996,31(5):387-395
Applicability of thin-layer headspace (TLHS) procedure giving an aqueous concentrate and also classical purge and trap (PT) in off-line mode to isolate and enrich volatile organohalogen compounds in common beverages was tested. Both enrichment tech-niques were used in combination with gas chromatography – electron capture detection (GC-ECD). TLHS, combined with direct aqueous injection (DAI)-GC-ECD, proved applicable in the determination of volatile organohalogen compounds in all studied beverages, while the PT in a version with no preliminary sample pre-treatment was of limited applicability. Detection limits of the TLHS-based procedure were in the order of 1 ppt. Content of volatile organohalogen compounds in a number of beverages available on the Polish market including mineral waters, beers, juices, carbonated and non-carbonated soft drinks, etc. was determined by means of TLHS-DAI-GC-ECD. 相似文献
23.
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
24.
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
25.
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
26.
In this paper an analytical method for determining the permeability of nonwoven filter fabrics is presented. The derived formula shows that the intrinsic permeability, fully characterizing the porous medium, depends on fabric porosity, n, fibre diameter, d, and a shape factor determined experimentally. 相似文献
27.
Maciej W. Rogoziski 《Systems & Control Letters》1989,12(5):449-453
An optimal predictor is developed for a singular random process generated by a known system driven by a white noise sequence. The properties of the predictor are compared with those of the optimal predictor for a nonsingular random process. 相似文献
28.
Studies on the influence of anthracene coal extracts on the carbonization process of medium- and high-rank coals were undertaken. Extracts from flame coal (Int. Class. 900) and gas-coking coal (Int. Class. 632) were used as additives. The blends prepared from the examined coals and the extracts exhibited better coking properties than the parent coals. The addition of extract to the coals gave an increase in the microstrength of the resultant cokes. The effects of co-carbonization of coking coals with extracts were increases in the size of the optical texture as well as in the degree of structural ordering of cokes. In the co-carbonization of semicoking coal with addition of coal extracts, a reduction in the size of the anisotropic units and a decrease in the crystallite height of cokes were observed. No modification of the basic anisotropy of coke from anthracite by coal extract was observed. With increasing extract content in anthracite/extract blends there was an increase in the degree of structural ordering of co-carbonization products. Extract addition was unable to modify the behaviour of fusinite. Based on the results of investigation of the influence of coal extracts on the carbonization of different-rank coals, a division of coals according to the modification of the optical texture of coke is given. 相似文献
29.
The article presents a review of most important research results as well as opinions about the role and importance of body image disturbances in the development and the course of eating disorders. It also contains a review of definitions of body image, and techniques used in the evaluation of this type of disorders. 相似文献
30.
A Gregor E Kostrzewska S Tarczyńska-Nosal H Stachurska 《Canadian Metallurgical Quarterly》1994,49(12-13):284-286
Fluorescence spectra of plasma porphyrin were measured in 6 patients with the acute intermittent porphyria (AIP), 30 patients with variegate porphyria (PV), 2 patients with hereditary coproporphyria, 2 patients with porphyria cutanea tarda, and in 6 patients with erythropoietic protoporphyria (EPP). It was found that the excitation and emission wavelengths at which maximum fluorescence is seen may help to diagnose and differentiate PV and EPP. In patients with AIP spectrum characteristic for porphyria of such a type was noted in all patients during the attack of disease and in only 33% of patients in remission. Fluorescence spectrum was normal in asymptomatic family members. In variegate porphyria spectrum with a characteristic maximum of fluorescence was noted in all patients during an attack and remission, and 62% of the asymptomatic family members. 相似文献