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Healthcare can be maintained well, when diagnosis is quick, accurate, cost-effective and painless. DNA and RNA based diagnosis may not reveal the right information for certain diseases. Identification and quantification of proteins and their folding mechanism are very important in diagnosis of diseases. Small quantities of proteins, which generally escape from detection and are responsible for the diseases, now can be quantified by protein nanotechniques which aids in the diagnosis. In this review, we have summarized the recent developments in nanotechnologies such as protein microarrays, biosensors etc. and their application in diagnosis of diseases at proteomics level have also been discussed.  相似文献   
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Young children's causal inferences   总被引:1,自引:0,他引:1  
We report 2 experiments that show a striking development between the ages of 3 and 4 years in children's ability to make causal inferences about sequences of events. The task in the first experiment was to work out what had caused the change to an object that started out as odd (noncanonical) in 1 way and ended up as odd in 2 ways--starting, for example, as a broken cup and ending as a wet and broken cup. When asked to choose the instrument that had caused the change, 3-year-olds often selected the instrument that could have caused the initial state (a hammer, in our example) and not the instrument that would produce the change. 4-year-olds hardly ever made this mistake. In the second experiment, the 3-year-olds were able to make the correct choice when the change was from a canonical to a noncanonical state (cup-wet cup) but had much more difficulty when the change was from noncanonical to canonical (wet cup-dry cup). The difference was much smaller in the older group. The first of these tasks can be solved simply on the basis of knowledge that a particular instrument can cause a particular effect without reference to the initial state. The second task requires attention to the differences between initial and final state. We conclude that the ability to make genuine causal inferences develops between the ages of 3 and 4 years.  相似文献   
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Tuberculosis remains major health problem in India and developing countries Immunodiagnosis has important role in screening, diagnosis and management of tuberculosis. SEVA TB ES-31 antigen has shown potential in detecting tuberculous IgG antibody in earlier studies from our laboratory. In the present study we have analysedSEVA TB ES-31 antigen specific immunoglobulinsIgM, IgA and IgG in clinically and bacteriologically confirmed pulmonary tuberculosis cases to determine the usefulness of specific immunoglobulin class in the diagnosis of patients attending the hospital. Of the 30 cases of pulmonary tuberculosis 25 (83.3%) were positive for IgG, 19 (63.3%) for IgM and 16 (53.3%) for IgA. On combining IgG and IgM positivity, sensitivity was increased to 93.3%. While combining IgG and IgA positivity, sensitivity increased to 90%. However specificity was decreased to 66.6% and 70% for both of these combinations respectively. It could be envisaged from this study that IgG antibody detection against ES-31 antigen showed acceptable sensitivity (83.3%) and specificity (86.6%) compared to IgM or IgA alone or in combination. When immune responses were analysed according to degree of sputum positivity, IgG response was observed to be predominant in all grades, compared to IgM or IgA antibody. The addition of IgM or IgA as an adjunct test increases the sensitivity but at the cost of specificity. Hence the detection of IgG alone is more useful compared to IgM or IgA assay, in detecting tuberculosis disease cases coming to the hospital.  相似文献   
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Serum (200.6±64.8 mg/dl) and urinary zinc (1186.0±265.5 mg/l.) of zinc miners at Zawar were significantly higher as compared to zinc smelter workers (Serum 89.7±9.9. mg/dl; Urine 590.0±32.1 mg/l.). Debari and Udaipur residents (Serum 104.0±18.6 mg/dl; Urine 735.0±180.2 mg/l.). This was most likely attributable to higher dietary zinc intake by zinc miners due to higher zinc content of foodstuffs grown in Zawar areas as compared to Debari and Udaipur.  相似文献   
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Urinary excretion of beta-aminoisobutyric acid (BAIB), was determined in 28 active and 12 inactive bladder cancer patients. Mean excretion of BAIB was higher in active cancer patients-187.8 mg/24 hours whereas it was 120.4 mg/24 hours in inactive cancer patients. The increased BAIB excretion in both disease groups was independent of tumour stage. BAIB appears to be a useful diagnositic aid in the assessment of bladder cancer patients.  相似文献   
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With the growing interest in the concept of free radicals in the pathogenesis of myocardial ischemia, it was thought worthwhile to study the changes in lipid peroxides and antioxidant enzyme glutathione peroxidase (GPx) in ischemic heart disease (IHD). The study was carried out on 76 patients of IHD-38 of acute myocardial infarction (AMI) and 38 of stable ischemic heart disease (SIDH). They were age and sex matched with 38 normal healthy controls. A significant increase (p<0.001) in lipid peroxides as malondialdehyde (MDA) (5.9±0.7 mmol/L) and a decrease in GPx (24.6±2.2 U/gmHb) was found in patients of AMI when compared with controls. There was no significant difference in these values in SIHD. Thus this study confirms the earlier findings that MDA and GPx are useful parameters in IHD and their magnitude is dependent on severity and/or duration of ischemia. We suggest that these tests would be of use in smaller institutions with limited facilities.  相似文献   
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Electricity     
In the early years of power generation the alternating voltage from a single coil (with 2 or more parallel paths) wascommutated to convert it to DC. Commutation essentially means reversing the negative polarity of the AC voltage so that the voltage produced does not alternately change, its sign and the current delivered by the generator flows in one direction. The purpose of producing direct current was that it could be used to run motors available in those days and light electric bulbs. AC motors which constitute more than 80% of today’s motors had not been invented at that time.  相似文献   
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