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Forty paediatric cases of A.R.F. (Acute Renal Failure) of various aetiology were included in the study. 60% of patients were less than 4 years of age with male predominance. 80% cases reported to us very late with oligoanuria of more than 24 hours (2-7 days). Diarrhoea, vomiting and fever were other dominant symptoms. Maximum cases were severely anaemic (87.5%) with mean Hb 7.73 +/- 1.9 gm%. 40% cases were of underweight while only one case (2.5%) was of over weight, inspite of volume excess in 40% cases. All 24 cases, who were estimated for serum albumin, found to have marked hypoalbuminemia. Mortality was found to be as high as 65% inspite of effective peritoneal dialysis in all cases. High mortality seems to be due to profound anuria of many days (because of marked delay in reaching the hospital), fever and malnutrition besides other factors as aetiology. 相似文献
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Thermochemical analyses of interfacial reactions in titanium, zirconium, and hafnium diboride reinforced oxidematrix composites have been carried out to evaluate the chemical compatibility. The chemical reactivity of these diborides with oxygen and the high volatility of B2 O3 ( l ) at reduced oxygen pressures are concerns during processing and operating conditions. The thermochemical stability and the vaporization behavior of B2 O3 ( l ) are discussed in terms of partial pressures of dominant gaseous species of the boron-oxygen system at 1700 and 2300 K. The TiB2 /ZrO2 and TiB2 /HfO2 systems are thermodynamically stable in a limited oxygen pressure range. The TiB2 /Al2 O3 system is stable, but the reactions in this system may apparently be accompanied by formation of gaseous products (B2 O3 , AlO, Al2 O, and lower boron oxides) in the presence of elemental oxygen. These thermochemical considerations are very useful in evaluating the effectiveness of oxides as diffusion barrier coatings on diboride reinforcements. 相似文献
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P. K. Khare J. M. Keller M. S. Gaur Ranjeet Singh S. C. Datt 《Polymer International》1994,35(4):337-343
The electrical conductivity of solution-grown ethyl cellulose (EC) films, 5–30 μm thick, has been studied in the sandwich configuration (metal–EC–metal) as a function of iodine concentration from 0.5 to 5.0 wt% ratio. The studies were conducted in the temperature range 333–383 K, while the field was varied over the range (3.0–5.5) × 104V/cm. Aluminium was used as the lower electrode, while the upper electrode was of Al, Ag, Cu, Au or Sn. Certain transient effects such as a large burst of current immediately after the application of field were observed. An attempt was made to identify the nature of the current by comparing the observed dependence on electric field, electrode material and temperature with the respective characteristic features of the existing theories of electrical conduction. The results show that the electrical conduction follows Ohm's law at lower fields, while at higher fields, space-charge limited current (SCLC) was observed. It was also found that Richardson–Schottky emission was responsible, to some extent, for the transport of charge carriers in the polymer. The conductivity of the films increased on doping with iodine. The dopant molecules are considered to act as additional trapping centes and provide links between the polymer molecules in the amorphous region, thus resulting in the formation of charge transfer complexes. 相似文献
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Evidence is presented showing that body fat distribution as measured by waist-to-hip ratio (WHR) is correlated with youthfulness, reproductive endocrinologic status, and long-term health risk in women. Three studies show that men judge women with low WHR as attractive. Study 1 documents that minor changes in WHRs of Miss America winners and Playboy playmates have occurred over the past 30–60 yrs. Study 2 shows that college-age men find female figures with low WHR more attractive, healthier, and of greater reproductive value than figures with a higher WHR. In Study 3, 25- to 85-yr-old men were found to prefer female figures with lower WHR and assign them higher ratings of attractiveness and reproductive potential. It is suggested that WHR represents an important bodily feature associated with physical attractiveness as well as with health and reproductive potential. A hypothesis is proposed to explain how WHR influences female attractiveness and its role in mate selection. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
30.
Girendra N. Kulsrestha Uma Shankar Jaipal S. Sharma Jasvinder Singh 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1991,50(1):57-65
Liquid-phase oxidation of cyclohexane with Co(III) catalyst and gaseous oxygen was found to be influenced by reaction temperature, catalyst concentration and the duration. Maximum adipic acid product selectivity (77%) with about 85% cyclohexane conversion was attained at 100°C using catalyst: cyclohexane molar ratio 0·08. Under these conditions more than 80% cyclohexane was converted in the first hour, although selectivity to adipic acid continued to increase for the next 5 h. Cyclohexyl acetate and cyclohexyl monoadipate were identified as important intermediates. This study supports the mechanism proposed by Schultz, J. G. D. and Opchenko, A., J. Org. Chem., 38 (21) (1973) 3729. 相似文献