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Veerappan Muthuviveganandavel Inho Hwang Vanattayen Anita Pattabiraman S. Malarani Chandrasekar Selvam Moorthy Hemalatha Muthuraman Pandurangan 《International journal of experimental pathology》2013,94(2):104-108
Alpha‐cypermethrin is an isoform of cypermethrin; it is an active pyrethroid used extensively to control a wide range of pests in agriculture and animal breeding. In this study four groups of six fish were examined. The first group served as a control in fresh water alone, with no pyrethroid. The second, third and fourth groups were exposed to alpha‐cypermethrin for 4, 8 and 96 h respectively. At the end of the each exposure period, the fish were sacrificed, and the required muscle tissues were collected for histological examination. The blood was drawn with heparinized needles and processed for serum enzymatic studies. Serum enzymes such as aspartate transaminase (AST), alanine transaminase (ALT), amylase, acid phosphatase (ACP) and gamma‐glutamyl transpeptidase (GGT) were measured at 4, 8 and 96 h. AST enzyme activity was significantly increased at 4 h, whereas ALT and amylase enzyme activities were significantly reduced at all the time points. ACP enzyme activity was significantly reduced at 4 and 8 h, whereas GGT enzyme activity was significantly increased at all the time points. Hepatocyte cytoplasmic vacuolisation and degeneration, rupture of blood vessels, and necrosis was found at all time points. Congestion of blood vessels, bulging, distortion of filaments, erosion and disintegration of blood corpuscles and hyperplasia of epithelium were found in treated gills at 4, 8 and 96 h. Breakdown of muscle fibres, vacuolation and accumulation of lipids and melanin in white muscle were observed in treated fish muscle at 4, 8 and 96 h. 相似文献
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Anita Saxena 《Global Heart》2013,8(3):203-212
Rheumatic heart disease continues to be a significant public health problem in many developing countries and in some of the aboriginal populations in developed countries. Echocardiography has become indispensable in the assessment of valve lesions secondary to rheumatic heart disease. It confirms the rheumatic etiology of valvular abnormality as the features are quite typical in most cases. It also helps to exclude nonrheumatic causes of valve lesions. M-mode and cross-sectional echo helps to assess the severity of valve abnormality and its hemodynamic effects on the heart. Further, color flow imaging evaluates the flow across a valve, both qualitatively and quantitatively. Serial echocardiography plays a crucial role in the follow-up of patients with rheumatic heart disease and is very helpful for determining the timing of intervention. Recently, addition of real-time 3-dimensional echocardiography has further improved imaging of cardiac valves, especially the mitral valve. 相似文献
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Jonathan L. Berliner Kushagra Verma Baron S. Lonner Phedra U. Penn Neil J. Bharucha 《The spine journal》2013,13(2):127-133
Background contextPrevious studies of the Scoliosis Research Society (SRS) 22 discriminative validity have lacked sufficiently matched study groups and were limited to a comparison with three or fewer subgroups of disease severity.PurposeTo evaluate the discriminative validity of SRS-22 by assessing the questionnaire's ability to discriminate among five groups of pretreatment adolescent idiopathic scoliosis (AIS) patients with increasing curve severity.Study designRetrospective review of prospectively administered surveys.MethodsTwo hundred eighty-six SRS-22 questionnaires were issued to two AIS pretreatment patient populations: 67 nonoperative and 219 preoperative. Study subjects were separated into five subgroups depending on the major Cobb angle (nonoperative 0°–19° and 20°–40° and preoperative 41°–50°, 51°–60°, and >60°). Each group (n=31) was matched for age (within 1 year) and sex (23 females and 8 males), resulting in a total of 155 study subjects. Analysis of variance was used to determine statistically significant differences (p<.05) between the five subgroups' domains and total scores.ResultsSignificant differences between study groups were found within two of the four domains (pain and image) and the total score. Both nonoperative groups (0°–19° and 20°–40°) demonstrated significantly less pain than the preoperative group (41°–50°) and significantly better self-image than all three preoperative groups. Both nonoperative groups' total scores were significantly higher than all three preoperative groups' scores, with the exception of the 20° to 40° subgroup versus the >60° subgroup. No significant differences were found between groups within the same planned treatment category.ConclusionsThe SRS-22 questionnaire demonstrated good discriminative validity between small nonoperative curves and larger surgical curves within the pain, image, and total domains. However, SRS-22 lacked the ability to differentiate between small intervals of curve magnitude, suggesting a limitation to the questionnaire's discriminative capacity. The discriminative validity of the Scoliosis Research Society (SRS) 22 has not been clearly defined. Our analysis of 155 adolescent idiopathic scoliosis patients evaluates the instrument's discriminative validity among five age- and sex-matched curve-severity subgroups. The SRS-22 questionnaire lacked the ability to differentiate between small intervals of curve magnitude, suggesting a limit to the questionnaire's discriminative capacity. 相似文献
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