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41.
42.
This study was carried out to investigate the effect of oral feeding of water extract of fresh leaves ofAzadirachta indica (Fam:Meliaceae) in streptozotocin induced diabetes and its associated retinopathy in rats. Treatment of the diabetic rats with aqueous extract of leaves ofA. indica at a dose of 250 mg/kg body weight for 16 weeks resulted in gradual but significant fall in blood glucose and improvement in serum total, LDL and HDL cholesterol and triacylglycerol which increased in diabetic rats. It also showed improvement in body weight and reversed retinopathy.  相似文献   
43.
Pleural effusion is one of the commonest presentations of tuberculosis, the clinical manifestations being typically abrupt resembling bacterial pneumonia. Since delayed hypersensitivity is the underlying immune response, bacterial load is very low. Owing to these facts, tuberculous pleurisy as an extra-pulmonary disease poses a diagnostic dilemma. The conventional bacteriological methods rarely detect Mycobacterium tuberculosis in pleural fluid and are of limited use in diagnosis of tuberculous pleurisy. We evaluated the efficacy of polymerase chain reaction (PCR) in the diagnosis of tuberculous pleurisy by targeting the gene segment coding for MPB64 protein specific forMycobacterium tuberculosis. Based on the clinical criteria, 82 patients with lymphocytic exudative pleural effusion were included in the study. Patients were analyzed in two groups; one group consisting of 48 patients of tubercular pleural effusion confimed by various diagnostic procedures and another group of 34 patients comprising of non-tubercular pleural effusion. There were no false positive results by PCR and the specificity worked out to be 100%. Twenty two patients tested positive for Mantoux with a sensitivity of 45%. ZN-staining for AFB was found in samples from 15 patients (20% sensitivity). ADA was positive for 28 patients with a sensitivity of 53%. PCR was positive for 32/48 patients (67% sensitivity). Thus, PCR was found to be more sensitive than any other conventional method in diagnosis of clinically suspected tubercular pleurisy.  相似文献   
44.
Effect of oral administration of 200 mg/Kg body weight of the aqueous extract ofOcimum sanctum (Tulsi) mixed with diet for eight weeks to diabetic (streptozotocin induced) rats was studied. There was significant reduction in fasting blood glucose, serum lipid profile, lipid peroxidation products, (LPO) and improvement in glucose tolerance. The aqueous extract also decreased LPO formation (thiobarbituric acid reactive substances TBARS) and increased antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPX), glutathione transferase (GT) and one antioxidant reduced glutathione (GSH) in plasma and rat liver, lung, kidney and brain. The decrease in TBARS and increase in GSH, SOD, CAT, GPX, and GT clearly shows the antioxidant property ofOcimum sanctum.  相似文献   
45.
Tocopherols (Tocs) are vital scavengers of reactive oxygen species (ROS) and important seed oil quality indicators. Nitrogen (N) is one of the most important fertilizers in promoting biomass and grain yield in crop production. However, the effect of different sources and application rates of N on seed Toc contents in oilseed rape is poorly understood. In this study, pot trials were conducted to evaluate the effect of two sources of N fertilizer (urea and ammonium nitrate). Each source was applied to five oilseed rape genotypes (Zheshuang 72, Jiu-Er-1358, Zheshuang 758, Shiralee, and Pakola) at three different application rates (0.41 g/pot (N1), 0.81 g/pot (N2), and 1.20 g/pot (N3)). Results indicated that urea increased α-, γ-, and total Toc (T-Toc) more than did ammonium nitrate. N3 was proven as the most efficient application rate, which yielded high contents of γ-Toc and T-Toc. Highly significant correlations were observed between Toc isomers, T-Toc, and α-/γ-Toc ratio. These results clearly demonstrate that N sources and application rates significantly affect seed Toc contents in oilseed rape.  相似文献   
46.
Recent advance in medical education is in correlation with the advances in information technology and thus computer-based learning is being increasingly employed. The objective of the present study was to design and evaluate an e-learning module in anatomy and assess the perceptions of students and faculty about this e-learning module. The participating students were randomized into three groups by block stratified randomization and Google groups were created for each of the three groups. The e-learning module was implemented in three sessions by rotating the three groups. Validated questionnaires were sent to faculty and participating students via Google forms to obtain feedback. The results of ANOVA showed that there was a significant difference among the groups in terms of marks obtained with conventional (F = 2.403, P = 0.103), online (F = 6.050, P = 0.005), and blended (F = 5.801, P = 0.006). Post hoc comparisons using the Tukey HSD test, about the gain of knowledge, indicated that the results were insignificant when comparing the conventional group with the online group, but were significant when comparing the blended group with the conventional and online group. The qualitative data regarding the perception of students toward e-learning were analyzed using thematic analysis. The introduction of an interactive e-learning module in anatomy was effective and well received by the students and faculty. The study showed that blended learning has a positive impact on the students' learning by improving cognitive gain and receptive perception for e-learning.  相似文献   
47.
Textbooks play an important part in the design of instruction. This study analyzed the presentation of fractions in textbooks designed for the elementary grades in Kuwait, Japan, and the USA. The analysis focused on the physical characteristics of the books, the structure of the lessons, and the nature of the mathematical problems presented. Findings showed USA and Kuwaiti mathematics textbooks are larger than Japanese textbooks; this larger size is consistent with a great deal of repetition. The Japanese texts do not address fractions until the third grade; they use linear models and connect fractions with measurement. In the USA and Kuwait, fractions are introduced in the first grade. The Harcourt text uses concrete material to help students learn fraction procedures. For the Kuwaiti series, the lessons depend on using some pictorial representation of the area model to illustrate fraction ideas. All these textbooks focus on standard algorithms as the main computational methods.  相似文献   
48.
Despite the critical role of individuals’ perceived security in an online environment, previous research has not attempted to comprehensively study the influences and interrelations between the determinants of online individuals’ perceived security. This research employs five theories to examine the interrelations that might exist between the antecedents of individuals’ perceived security in online environment in Malaysia. It is the first attempt to empirically examine the interrelations of the confidentiality related factors identified in the literature which is a significant original contribution. A questionnaire was the primary research methodology and structural equation modeling was employed to test the hypotheses. The findings suggest that individuals’ perceptions about security are significantly influenced by their perceived technical protection while technical protection was found to be influenced by website design features. Moreover, it was found that individuals’ perceptions toward internally provided assurances are highly influenced by externally provided assurances. However, the results found no significant relations between internally and externally provided assurances about a website's security. The findings imply that e-retailers should launch well-designed websites and communicate the technical protection capabilities of their websites to address individuals’ security concerns. The results also suggest that e-traders should consider the factors influencing individuals’ security perceptions when designing/developing their websites.  相似文献   
49.
Plants encounter a variety of stresses in natural environments. One-year-old pot-grown trees of pear (Pyrus pyrifolia Nakai cv. Cuiguan and Wonhwang) were exposed to two heat stress regimes. Under constant short-term heat stress, chloroplasts and mitochondria were visibly damaged. Relative chlorophyll content and maximum photochemical efficiency of photosystem II were significantly decreased, which indicated that the leaf photosynthetic capability declined. Under chronic heat stress, mesophyll cell ultrastructure was not obviously damaged, but leaf photosynthetic capability was still restrained. As chronic heat stress was a simulation of the natural environment in summer, further study of the responses under this stress regime was undertaken. Ascorbate peroxidase (APX) activity was increased in ‘Cuiguan’, but not in ‘Wonhwang’. Inducible expression of PpAPX genes in the cytoplasm, chloroplasts and peroxisomes was consistent with increased APX activity in ‘Cuiguan’, whereas only weak induction of PpAPX genes was observed in ‘Wonhwang’. The isoenzymes cytosolic APX1 (cAPX1) and stromal APX (sAPX) were confirmed to be localized in the cytoplasm and chloroplasts, respectively.  相似文献   
50.
Former Director of the International Bureau of Education of Unesco in Geneva. Author of numerous publications in international and comparative education as well as in the fields of literacy, educational reform and planning.  相似文献   
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