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21.
AIM: To evaluate the validity of cumulative rim/disc area (RA/DA) curve analysis as a clinical tool for the identification of glaucoma induced optic disc pathology. METHODS: 71 normal and 83 glaucomatous eyes were evaluated from a series of 154 subjects recruited for this study. For each eye, the cumulative distribution of RA/DA was calculated from 36 equally spaced rim sectors of each optic disc obtained by the automatic evaluation of simultaneous videographics (Image-net X Rev.3/51b). To increase the sensitivity of this analysis in early glaucoma and in normal eyes, these cumulative curves were subsequently divided into two equal segments and the slopes of their respective regression lines compared. RESULTS: The median RA/DA value obtained from the 36 sectors was significantly different in glaucomatous eyes compared with normals (p < 0.001). Nevertheless, the curves (5th-95th percentile of the cumulative curves distribution) of early glaucomatous eyes fell within the normal range. When the cumulative curve of these marginal cases was then divided into two equal segments, the comparison of the slopes of the regression lines showed a significant difference (p < 0.05) in 100% of early glaucomatous eyes. Furthermore, normal eyes were shown to be true negatives in 93% of the cases in which no significant difference between the two slopes was observed. CONCLUSION: Analysis of the RA/DA cumulative curve from 36 sectors of the optic disc was a valid method for the identification of glaucomatous disc pathology; however, a further calculation of the slopes of the two RA/DA regression lines was needed to identify early glaucomatous damage. 相似文献
22.
A comparative analysis is given of the gastric cancer incidence in the Tjumen Province for a period of 1959--1973. There was noted a direct dependence between the rate and number of risk factors (the complexes of unfavourable factors) in males and females. A conclusion is made that a higher incidence rate (1.7 times more) of gastric cancer among males may be attributed to the complexes of infavourable factors to which they are subject to a greater extent, 1.7 times as often as females, (mainly to bad habits) but not to biological features of the organism. Elimination of these harmful effects on the body would lessen the risk of this affection. 相似文献
23.
Bilateral amyloidosis of the orbit. A case report with pathogenetical considerations 总被引:2,自引:0,他引:2
OA Jensen 《Canadian Metallurgical Quarterly》1976,173(1):70-78
24.
AS Pavlov VS Datsenko MA Fadeeva OA Zamiatin EV Kizhaev 《Canadian Metallurgical Quarterly》1980,26(3):3-8
The authors present an analysis of the causes of radiation induced complications in 383 patients referred to the Chair of Clinical Radiology from different medical institutions of the country. It was found that under distant gamma therapy, to prevent the development of complications the value of TDF-factor should not exceed 105--110, for the associated radiotherapy--130--140, and that for close focal roentgenotherapy--130--150. In vast majority of patients (95.3%) the complications resulted from surpassing the normal tissue tolerance. To prevent radiation injuries it is suggested to take into consideration the TDF-factor values, while in planning radiotherapy to choose such schedules of irradiation, which preclude any surpassing of the tolerance of normal tissues and organs adjacent to the tumor. 相似文献
25.
II Kalachev AN Baídus' OA Ivanova EA Ganina IA Boldyrev EA Svetoch 《Canadian Metallurgical Quarterly》1997,(6):32-37
Unlike the glanders agent, the superficial structures of the melioidosis agent were demonstrated to be responsible for marked was immunosuppressive activity. Some antigenic fractions suppressing the blast transformation of lymphocytes, reducing the count of T helpers and profoundly potentiating the infection in vivo were isolated from P. pseudomallei cells. The immunogenic and immunosuppressive activities of both agents' superficial structures were studied by high performance chromatography. Antigenic complexes that were able to protect immunized laboratory animals against fatal infections and to prevent bacterial carriage due to the activation of T cells and to the bacterial activity of macrophages were identified. A composition comprising several immunogens was found to provide an additive protective action against both causative agents. Therefore, the composition may be considered to be a prototype of a molecular antipseudomonadic vaccine. 相似文献
26.
AA Bakova BD Brondz OA Fedorkina VA Gusev AI Gordienko IuS Krivoshein IuL Krivorutchenko TG Prokopenko IA Popov 《Canadian Metallurgical Quarterly》1994,39(4):187-189
The possibilities of using influenza A (Leningrad) 385/80 (H3N2) virus matrix protein-specific FITC-labeled D8 monoclonal antibodies in immunofluorescence assays were investigated. The virus antigen accumulation was detected in chorioallantoic cells of chick embryos. Exhibiting the type-specific properties, the fluorescent antibodies stain the perinuclear space, cytoplasmic membrane, and granular structures in the cytoplasm of infected cells. The haemagglutination test tires in the corresponding specimens were at least 1:16. 相似文献
27.
Yu. S. Tveryanovich S. V. Fokina A. V. Kurochkin E. N. Borisov M. G. Krzhizhanovskaya M. D. Bal’makov 《Glass Physics and Chemistry》2016,42(2):172-176
Using a method of laser ablation, a number of AgI–chalcogenide glass nanolayered films has been obtained with different thicknesses of the layers (10, 25, 50, and 100 nm). In order to study α ? β phase transition in AgI, X-ray phase analysis has been carried out in the temperature range from 30 to 200°C. A correlation between the layer thickness and the temperature of the α → β phase transition during the lowering of the temperature is found. An explanation of the correlation is proposed. 相似文献
28.
Gold (I)-containing compounds, including aurothioglucose (ATG), are potent in vitro inhibitors of several selenocysteine-containing enzymes. Gold compounds have also been shown to potentiate the virulence of several viruses in mice, including coxsackievirus, implicated as a possible infectious agent in Keshan disease. One possible mechanism by which gold compounds may be increasing the virulence of viral infections in mice is by acting as a selenium antagonist in vivo and inducing oxidative stress. To investigate the possible role of gold compounds in inducing oxidative stress in mice, we assessed the ability of ATG administered in vivo to inhibit the activity of the selenocysteine-containing enzymes thioredoxin reductase (TR) and glutathione peroxidase (GPX1). Doses as low as 0. 025 mg ATG/g body weight caused significant and prolonged inhibition of TR activity in all tissues examined. No such inhibition of GPX1 activity was seen, indicating differential in vivo sensitivity of the enzymes to inhibition by ATG. In liver and heart, some recovery of TR activity was observed after a 7-d period, but no recovery was observed in pancreas or kidney. Because TR is involved in several important cellular redox functions, its inhibition most likely will affect multiple cellular processes. These results indicate that in vivo administration of ATG results in significant and long-lasting inhibition of TR activity. Such inhibition of TR could lead to increased levels of oxidative stress in vivo, thereby increasing the virulence of several viruses including the coxsackievirus. 相似文献
29.
The paper concerns variations in some parameters of humoral immunity in children with phenylketonuria examined at varying time (in the presence of specific dietetics and after its discontinuation). It is concluded that in children over 5 years of age, the hyperphenylalaninemia newly occurring after discontinuation of dietetics does not exert any material effect on the function of the mature enough immune system. 相似文献
30.
Translated from Poroshkovaya Metallurgiya No. 10 (346), pp. 15–17, October, 1991. 相似文献