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211.
This study evaluates the validity of claims that Working Memory (WM) training is an effective and legitimate school-based maths intervention. By analysing the current developments in WM in the fields of neurology and cognitive psychology, this study seeks to analyse their relevance to the classroom. This study analyses memory profiles of children and maths performance previous to, and after a 3 week school-based, teacher led, intervention programme. Results indicate that although WM improved, it also improved for the control group, who did not undergo training. No significant far-transfer to maths results were demonstrated during the study.  相似文献   
212.
In this pedagogical article, we elucidate the direct derivation of total power emitted by an accelerating charged particle, known as Liénard’s generalisation, using differentiation under integral sign technique.  相似文献   
213.
The research reported in this article investigated the effect of manufacturing strategy on organizational performance in the Malaysian electrical and electronic sector. It was revealed that a cost‐based strategy greatly affected the performance of organizations participating in this study. This result implied that a cost‐based strategy is still a dominant concern for manufacturing firms. The information gathered through this study is useful for strategy formulation and for understanding how a strategy can lead to improved organizational performance in general.  相似文献   
214.
After administration, ethanol and its metabolites go through the kidneys and are excreted into urine. The kidney seems to be the only vital organ generally spared in chronic alcoholics. Therefore, we investigated the multiple effects of chronic ethanol exposure on renal function tests and on oxidative stress related parameters in the kidney. Chronic ethanol (1.6 g ethanol/ kg body weight/ day) exposure did not show any significant change in relative weight (g/ 100g body weight) of kidneys, serum calcium level or glutathione s-transferase activity. However, urea and creatinine concentration in serum, and TBARS level in kidney elevated significantly, while reduced glutathione content and activities of glutathione peroxidase, glutathione reductase and superoxide dismutase diminished significantly after 12 weeks of ethanol exposure. Catalase activity showed increased activity after 4 weeks of ethanol exposure and decreased activity after 12 weeks of ethanol exposure. Genesis of renal ultrastructural abnormalities after 12 weeks of ethanol exposure may be important for the development of functional disturbances. This study revealed that chronic ethanol exposure for longer duration is associated with deleterious effects in the kidney.  相似文献   
215.
Antitryptic, antichymotryptic and alpha 2- macroglobulin activities were measured in sera of normal nonpregnant and normal pregnant women and women with tubal ectopic pregnancy and molar pregnancies in the first 5 to 7 weeks of pregnancy calculated from the last menstrual period. While alpha 2-macroglobulin decreased in early normal pregnancy compared to nonpregnant state (p<0.001), in ectopic and molar pregnancies there was an increase in alpha 2- macroglobulin activity (p < 0.001), as compared to nonpregnant and normal pregnant women. Antitryptic activity did not increase in normal and ectopic pregnancy, however was increased in molar pregnancy (p < 0.01). Antichymotryptic activities did not show a change either in normal pregnancy or in cases of ectopic and molar pregnancy. Drop in alpha 2- macroglobulin activity to near normal levels in ectopic, 6 weeks post surgery, correlated well with the decrease in β-hCG. However, in molar pregnancy, alpha 2- macroglobulin remained elevated even when the β-hCG levels in serum returned to zero 10 weeks after surgery. The studies suggest a major role for circulating proteinase inhibitors especially alpha 2-macroglobulin in regulating proteinase activity in normal, ectopic and molar pregnancy.  相似文献   
216.
The present study deals with the evaluation of glycemic profile of aqueous extract of Cajanus cajan leaves in streptozotocin induced type 2 diabetic rats. Single oral administration of graded doses of aqueous extract of Cajanus cajan leaves showed significant increment of 14.3 % in fasting blood glucose levels of normal rats. The sub diabetic and mild diabetic models have also shown hyperglycemic effect from the same variable doses of the extract. The dose of 1000 mg/kg showed the maximum rise of 17.1, 71.2 and 50.7 % in Blood glucose levels of normal, sub and mild diabetic rats respectively during glucose tolerance test. The study of leaves was taken into consideration on the basis of earlier reported hypoglycemic activity of Cajanus cajan seeds. However the results observed were found just opposite and therefore it may be useful in controlling hypoglycemia, occasionally caused due to excess of insulin and other hypoglycemic drugs.  相似文献   
217.
Extremozymes that function in the extreme environmental conditions of temperature, pressure, pH, and salinity are of great importance for industrial processes and scientific research. Apart from understanding the principle behind the stability of such enzymes, there has been considerable effort to isolate enzymes from extremophiles (organisms that live in extreme environmental conditions) as well as modify enzymes from mesophiles (organisms that live in normal environmental conditions) to convert them into extremozymes.  相似文献   
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A mycobacterial excretory-secretory protein fraction ESAS-7 purified by 50% ammonium sulphate precipitation followed by SDS-PAGE fractionation was evaluated by penicillinase enzyme linked immuno-sorbent assay (ELISA) for its sensitivity and specificity in the diagnosis of pulmonary tuberculosis. At a “cut off” serum dilution of 600, 38 (90%) of 42 sera from bacteriologically confirmed tuberculosis cases, 15 (100%) of 15 sera from bacteriogically negative but anti tubercular therapy (ATT) responded cases, 3 (7%) of 43 sera from normal healthy subjects and 4 (8%) of 48 sera from non tuberculous disease control cases gave positive reaction for tubercular antibody to ESAS-7 antigen fraction containing predominantly 33-kDa protein with a sensitivity of 90% in bacteriologically confirmed cases and specificity of 92%. Further, this diagnostic assay using the ESAS-7 antigen is more sensitive requiring as little as one nanogram antigen per test compared to use of 100 nanogram EST-6 antigen reported earlier. Thus use of ESAS-7 antigen for antibody detection has good diagnostic potential with improved specificity in pulmonary tuberculosis.  相似文献   
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