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991.
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   
992.
In this study the effect of thiazide diuretic compound on the protein and cholesterol contents in the testes of albino rats as the experimental model. The drug thiazide was administered orally daily for 10,20 and 30 days at the dose of 100mg/kg body weight. Total protein decrease in the testes of rats were evidenced may be due to the side effects of thiazide drug compound which is linked with the hyponatremia and protein metabolism. An elevated level of cholesterol contents observed in thiazide treated rats also revealed that the side effect of drug compound thiazide and also may be due to the stimulation of catecholamine which is stimulated therefore, the biochemical estimation such as protein and cholesterol in the testes after the thiazide treatment determined the effectiveness of diuretic drug compound would provide clinical evidences of their side effects.  相似文献   
993.
Surveillance of drinking water is essentially a health measure intended to protect the public from water borne diseases. Hydride generator accessory coupled with atomic absorption spectrophotometer was used to analyze arsenic level in 49 ground water samples collected from different areas of Delhi. Arsenic level in ground water samples was in the range of 0.0170 to 0.100 ppm (Mean-0.0431, Standard Deviation-0.0136, Std. error of Mean-0.00194) with minimum concentration at Raney Well No. 7 (0.0170 ppm) and maximum at Kotla Mubarak Pur (0.100 ppm). Arsenic containing sediments and percolation of chemicals into soil as the result of dumping of garbage rich in chemicals into open landfills could be the possible source of arsenic in ground water of Delhi. Extensive survey and continuous monitoring is required to be made to assess the magnitude of problem and earlier intervention.  相似文献   
994.
Rolling dice and tossing coins can still be used to teach probability even if students know (or think they know) what happens in these experiments. This article considers many simple variations of these experiments which are interesting, potentially enjoyable and challenging. Using these variations can cause students (and teachers) to think again about the statistical issues involved – and learn in the process.  相似文献   
995.
In this article we briefly review the application of electrons in the field of microscopy. Two types of microscopes are discussed, the electron microscope and the tunneling microscope. It is emphasized that in both the applications the electron behaves as a quantum mechanical object.  相似文献   
996.
Conclusion The pursuit of meaning through reflection is an ultimate goal of teacher education. The reading reaction sheet strategy is one way to help methods students construct meaning about science teaching and learning, and is applicable to other college courses where considerable reading is expected. Furthermore, through instructor modeling (Kyle, Abell, & Shymansky, 1989; Yeany & Padilla, 1986), preservice teachers are more likely to employ techniques for reading in the content area in their own teaching. Thus the reading reaction sheet strategy illustrates the integration of research in reading, writing, and science education and its application to classroom practice.  相似文献   
997.
The capacity of newborn infants to smooth-pursuit eye movements in single-target tracking and in optokinetic nystagmus to a moving striped field was examined utilizing DC electrooculography. Smooth-pursuit movements were observed in all infants who were alert during testing, but they occupied less than 15% of viewing time during single-target tracking. The velocity of smooth-pursuit segments in single-target tracking increased linearly to a target velocity of 19 degrees/sec and deteriorated rapidly at faster speeds. No smooth pursuit occurred above 32 degrees/sec in single-target tracking. By contrast, optokinetic nystagmus was observed at all field velocities to 40 degrees/sec, but the speed of the mean slow component increased linearly to 25 degrees/sec and diminished above that field velocity. Infant optokinetic nystagmus differed strikingly from that of adults in that tonic ocular deviation was in the direction of field movement rather than away from it. This feature of neonatal optokinetic nystagmus is consistent with deficient foveal function and suggests that the relatively poor smooth-pursuit performance of newborns may be related to foveal immaturity.  相似文献   
998.
News interviews are contexts in which political responsibilities are articulated and negotiated. Although the accountability interview is recognized as a commonsense practice in journalism, and the research on political interviews is substantial, it partly remains to explore how responsibilities are negotiated in different forms of questioning in journalism. This study investigates three generic forms of questioning: accountability questioning, the clarifying of promises, and the principal assessments. Key features of the different forms are specified. The empirical study investigates how the questionings are performed in news on industrial crises in Sweden, in the different political regimes in the 1970s and the 2000s. The data consist of 27 news interviews with the formally responsible Ministers. The method is based on Conversation Analysis and includes detailed analyses of questions and answers. The study shows (1) how the forms of questioning differ when it comes to the action agenda and in how responsibilities are invoked and negotiated; (2) how the questionings tend to reproduce particular expectations of Governmental interventions; (3) how increased assertiveness and adversarialness in interviewing coincide with reduced expectations of political responsibilities.  相似文献   
999.
麦克玛斯特大学"问题学习法"   总被引:51,自引:0,他引:51  
本文从麦克玛斯特大学“问题学习法”(problern-based learning)实施过程的各个方面:教育目标、教学安排、教学活动、教学评价、教学资源等方面介绍了PBL的教学过程,总结了麦克玛斯特大学PBL课程设置以学生为本,培养学生的学习态度和终身学习的能力以及在教学过程中倡导以生物—心理—社会医学模式培养适合社会发展需要的医生的经验。  相似文献   
1000.
Holder (1988) has raised several objections to our work on the role of exteroceptive contextual stimuli in taste-aversion learning by rats. Our main conclusion from that work is that tongue-tactile stimuli from the drinking spout constitute the likely basis for findings of contextual bottle control over learned taste aversions. Holder suggests that our results are confounded by taste cues from the fluid containers. We refute this suggestion by presenting data from two experiments showing contextual bottle control, even though potential taste cues from the drinking bottles were eliminated. We also point to the fact that some of Holder’s criticisms are based on misreadings of our various reports.  相似文献   
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