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61.
Yeldose Sonu S. S. Avinash Sreekantha K. Arun Kumar M. Malathi A. R. Shivashankara 《Indian journal of clinical biochemistry : IJCB》2016,31(3):326-331
Given the paucity of studies conducted to know the effect of suddenness and earlier onset of endocrinological changes associated with hysterectomy, on the serum and urinary levels of calcium, magnesium and phosphate the present study was conducted to compare the levels of calcium, magnesium and phosphate in serum and urine of hysterectomised and natural menopausal south Indian women. This is a cross-sectional observational study. The study included three groups of 30 healthy premenopausal, 30 early surgical menopausal and 30 natural post menopausal women. Women suffering from any endocrine disease were excluded. Analysis was performed in serum and urine sample. The levels of calcium, magnesium and phosphate in serum and calcium/creatinine, magnesium/creatinine and phosphate/creatinine ratio were estimated in urine by spectrophotometric method. Hysterectomised women (serum calcium: 8.7 ± 0.09 mg/dl; urine calcium/creatinine: 0.16 ± 0.02) have significantly low serum calcium (p < 0.001) and high urinary calcium/creatinine (p = 0.002) ratio and post menopausal women (serum magnesium: 2.1 ± 0.03; serum phosphate: 4.4 ± 0.16; urinary calcium/creatinine: 0.17 ± 0.02; urinary magnesium/creatinine: 0.09 ± 0.01) have significantly high serum magnesium (p = 0.016), serum phosphate (p = 0.043) and high urinary calcium/creatinine (p = 0.002), magnesium/creatinine ratio (p = 0.025) compared to healthy pre menopausal women. Post menopausal women (serum calcium: 9.1 ± 0.08) have significantly high serum calcium and phosphate compared to hysterectomised women (serum phosphate: 3.93 ± 0.11). Hysterectomised women have significantly low serum calcium, oestrogen and high urinary calcium/creatinine ratio compared to healthy premenopausal women and low serum calcium and low serum phosphate compared to natural postmenopausal women. Natural postmenopausal women had low serum oestrogen and high serum magnesium, serum phosphate, urinary calcium creatinine ratio and urinary magnesium creatinine ratio compared to healthy premenopausal women. 相似文献
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63.
Dipanjan Ghosh 《Resonance》2006,11(10):69-77
Index fossils are commonly found, widely distributed fossils that are limited in time span. They are used for the determination
of the age of organic rocks and other fossil assemblages and also help to establish relationships be-tween rock units. Index
fossils of plant origin are very rare. In this article, I describe many of their important features, uses, and some of their
limitations. 相似文献
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键级和化合价的分子轨道理论 总被引:1,自引:0,他引:1
本文译自美国《Journal of chemical Education》1988年第8期.作者简介了密立根布居数分析法,并以此为基础讨论了键级和化合价,应用了别致的原子轨道线性组合分子轨道理论(LCAO—MO)的矩阵公式.最后给出了一些简单分子的计算结果,以说明这个理论的应用. 相似文献
66.
Fang-Ying Yang Kaushal Kumar Bhagat Chia-Hui Cheng 《International Journal of Science Education》2019,41(10):1347-1365
The purpose of this study was to compare the associations of epistemic beliefs in science, performance of scientific reasoning in university students from Taiwan and India, and the relations with their science learning experiences. A total of 126 university students including 67 from Taiwan and 59 from India who had science and mathematics backgrounds were involved in the study. Students’ epistemic beliefs in science were assessed by the SEV questionnaire, while their reasoning performance and learning experiences were prompted by open-ended questions and survey items. Content analysis was performed to analyze their scientific reasoning, and correlation analysis, t tests and ANOVA were applied to reveal the associations between variables. The results showed that students from both countries differed in epistemic beliefs in the dimensions of certainty, development and justification. While few students from either country performed successfully in identifying genuine evidence and giving full rebuttals, Taiwanese participants seemed to demonstrate slightly better scientific reasoning. It was found that the Indian students were more balanced in receiving structured and engaged learning experiences. Varying associations for the students from the different countries were found between epistemic beliefs and scientific reasoning performance, and between epistemic beliefs and science learning experiences. 相似文献
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Amartya Kumar Dutta 《Resonance》2004,9(1):61-63
Inadvertently, an earlier draft of this article got printed in the November 2003 issue and, since the new draft clarified
some of the points, the section ‘Brahmagupta’s lemma and modern algebra’ of the final draft and a few small remarks are being
reprinted for the reader’s convenience. The error is regretted. 相似文献
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70.
Amartya Kumar Dutta 《Resonance》2006,11(3):51-68
Āryabhata (born 476 CE) is regarded as a pioneer of mathematical astronomy in ancient India. In this three-part article, I
shall discuss one important contribution of Āryabhata in astronomy involving the least technical background —the principle
of axial rotation (Part 1) and computations on the sidereal day (Part 2). Portions of 4 verses, pertaining to Earth’s rotation,
from his famous treatise Āryabhatīya will be quoted. In Part 3, I shall give a brief historical account on the concept of
axial rotation of Earth. 相似文献