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61.
62.
Living organisms ranging from bacteria to human beings exhibit 24-h rhythms in various behaviours and physiological processes. Matching of the period of such rhythms with that of the daily environmental cycles gives an impression that they are mere passive responses to environmental changes. Here, we discuss the change in our perception about daily biological rhythms, from their identity as rhythmic phenomena occurring as passive response to environmental changes, to the biological clocks. This is the first article in a series of articles on circadian rhythms which will cover discussion on the genetic and molecular basis, circadian organization and its adaptive significance.  相似文献   
63.
Distance education has a history of over four decades in India. There has been a vast growth in the number of learners who need education and thus also the corresponding channels of providing education. Due to the constraints of the traditional educational sector, open and distance learning has been found to be a workable alternative strategy in India. This paper traces the evolution and diversification of open learning in India by examining various factors that led to the growth and success of open learning. This system, as other systems of education, is not free from problems and a critique is provided on the various factors affecting the smooth functioning of India’s open and distance learning system.  相似文献   
64.
To enhance students’ critical thinking in an undergraduate general science course, we designed and implemented active learning modules by incorporating group-based learning with authentic tasks, scaffolding, and individual reports. This study examined the levels of critical thinking students exhibited in individual reports and the students’ critical thinking level change over time. Findings indicated that students’ average critical thinking level fell in the category of “developing”, but students’ scores on individual reports revealed a statistically significant increase. The study suggested that the active learning strategies employed in the study were useful to promote student critical thinking.  相似文献   
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66.
Silver is ingested in India in the form of varak, Ayurvedic bhasm and water contained in silver utensils, but nobody knows their effects. We have examined the effect of interaction of silver ingested in the form of varak (leaf), bhasm (ash) and water (colloidal solution) on some essential elements (Na, K, Ca, Mg, Cu, Fe and Zn) in blood, liver, spleen and kidneys of chicks. The results showed significant rise of silver in all the tissues and significant fall in copper in the blood. The greatest rise was obtained in blood silver by silver sol while it had the lowest amount of silver. Iron significantly increased in tissues but somewhat decreased in blood. Zinc content increased in all the tissues by leaf and ash but decreased by sol. No consistent pattern was seen in case of other elements.  相似文献   
67.
Neural tube defects are congenital structural abnormalities of the brain and vertebral column resulting from improper or non-timely closure of the neural tube. Prevalence of neural tube defects is reported to be higher among women with diabetes mellitus and obesity. This study was designed to investigate the relation between the presence of dyslipidemia in antenatal patients and the risk of fetal neural tube defects. The present study was an observational, cross-sectional study involving 129 pregnant women in 16 to 18 weeks gestation period. Of these, 80 women had normal pregnancies and 49 were clinically high-risk cases for neural tube defects. Fasting blood samples were analyzed for blood sugar and lipid profile by enzymatic assay and alpha-fetoprotein levels using Enzyme Immunoassay. Alpha-fetoprotein (AFP) values were converted to Multiples of Median (MoM) appropriate for the gestational age. Based on AFP values, women were labeled as screen negative (AFP <2 MoM, n= 102) and screen positive (AFP > 2 MoM, n =27). Screen positive women were further evaluated by ultrasound and 21 women were found to carry a neural tube defects positive pregnancy. Statistical analysis was done on SPSS software. Body weight of the women showed a significant positive correlation with serum triglycerides, plasma sugar and AFP MoM values. A significant difference was observed in serum cholesterol levels (p= 0.038), triglycerides (p=0.001) and plasma sugar levels (p=0.002) between normal women and those with neural tube defects positive pregnancy. The Odds ratio for neural tube defects risk in dyslipidemic cases was 24.23 (CI 4.73 − 148.60) with a relative risk of 12.12. Dyslipidemia especially hypertriglyceridemia was found to be significantly associated with fetal neural tube defects.  相似文献   
68.
Premature coronary artery disease (CAD) is common in India. We, therefore, studied oxidative stress, dyslipidemia, and high sensitivity-C reactive protein (hs-CRP) levels in young CAD patients. Present study consisted of male CAD patients below 40 years and age and sex matched healthy controls (n=30 each). Fasting blood samples were analyzed for serum lipid profile, malondialdehyde, antioxidant enzymes and hs-CRP levels. Dyslipidemia was observed in 90% of the young CAD patients, of which 72.2% showed increased serum triglycerides and decreased HDL-cholesterol. LDL-cholesterol levels were high in 77.8%. Serum malondialdehyde and hs-CRP levels were increased significantly (p<0.0001) as compared to controls. hs-CRP levels were in high risk range in all the young patients. However, glutathione peroxidase activity was reduced significantly (p<0.05). Our data suggests that elevated hs-CRP levels along with dyslipidemia and oxidative stress adds to the predictive value of premature CAD in young Indians.  相似文献   
69.
Genomic DNA from a clinical isolate ofMycobacterium avium-intracellulare complex was purified and cloned in PBR 322 at the tetracycline resistance site using Bam HI restriction enzyme. A 16 kb cloned fragment was purified, radiolabeled and used as a probe. Genomic DNA isolated from nineteen MAC strains, threeM. tuberculosis strains and oneM. kansasii strain were digested with Eco RI restriction enzyme, Southern blotted and hybridized with the 16 kb cloned and labeled fragment. Twelve MAC strains showed positive hybridization although five strains gave faint signals. Positive hybridization was noted in two out of the threeM. tuberculosis strains, possibly due to shared DNA homology. No signal was received from the singleM. kansasii strain used in this study.  相似文献   
70.
The purpose of this study is to measure the effects of carbohydrate ingestion during exercise in the heat by measuring markers of gastrointestinal damage and inflammation. Methods: Active subjects (n?=?7) completed two 60-min running trials in a heated environment (70% VO2max, 30°C). At minute 20 of exercise, subjects consumed a carbohydrate gel (Cho) (27?g), or a non-carbohydrate placebo (nCho). Plasma endotoxin, I-FABP, TNF-α, IL-6, IL-1β, IL-10, and MCP-1 were measured pre-exercise, 20-min post-exercise, and again 2-h, and 4-h post-exercise. Results: Endotoxin increased 20-min post-exercise compared to pre in the Cho trial only (p?=?.03). I-FABP levels increased 20-min post-exercise in the Cho trial only compared to pre-exercise (p?=?.003). I-FABP levels were also increased in Cho trial 20-min post-exercise when compared to same time point in the nCho trial (p?=?.032). TNF-α increased 20-min post-exercise in the Cho trial only compared to pre (p?=?.03). Plasma IL-6 concentration increased 20-min post-exercise when compared to pre in both the Cho (p?=?.002) and nCho (p?=?.009), but remained elevated at the 2-h time point in the nCho trial (p?=?.03). I-FABP and several plasma cytokines (TNF-α, MCP-1, Il-6) returned to baseline sooner in the Cho trial. Conclusions: Ingestion of carbohydrate gel during exercise in the heat enhances markers of gastrointestinal wall damage.  相似文献   
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