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Among the heavy metals, lead still remains the major toxic pollutant of the environment. Human exposure to lead can occur through numerous pathways including air, food, dust, soil, and water. In the present study 14 lead poisoned patients with non-occupational lead exposure were evaluated. They were followed up and compared against the controls with no history of lead exposure. The patients had high blood lead levels and symptoms of weakness, dizziness, abdominal pain, generalized body ache, loss of appetite, and anxiety. Repeated course of chelation therapy helped to bring down their body burden of lead. Alternative sources for lead exposure can cause severe lead poisoning in general population. Screening and medical management of such individuals is very important to identify and eliminate sources of lead. The treatment and management requires a thorough medical evaluation and environmental intervention.  相似文献   
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Output reversibility involves dynamical systems where for every initial condition and the corresponding output there exists another initial condition such that the output generated by this initial condition is a time-reversed image of the original output with the time running forward. Through a series of necessary and sufficient conditions, we characterize output reversibility in linear discrete-time dynamical systems in terms of the geometric symmetry of its eigenvalue set with respect to the unit circle in the complex plane. Furthermore, we establish that output reversibility of a linear continuous-time system implies output reversibility of its discretization. In addition, we present a control framework that allows to alter the system dynamics in such a way that a discrete-time system, otherwise not output reversible, can be made output reversible. Finally, we present numerical examples involving a discretization of a Hamiltonian system that exhibits output reversibility and an example of a controlled system that is rendered output reversible.  相似文献   
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In a perspective study, the ascitic fluid and serum concentration of total cholesterol, total proteins and albumin in a group of 45 patients was studied. Patients with nonmalignant or cirrhotic ascites were compared with patients having malignancy related ascites and it was proved that the ascitic fluid cholesterol and the serum ascites albumin gradient helped to differentiate cirrhotic from malignant ascites. These two parameters showed a remarkable relationship to the presence/absence of malignancy. Non malignant ascites patients had ascitic fluid cholesterol values of 19.41±8.33 mg/dl, as against the malignancy related ascites patients, who showed levels of 95.87±1.24 mg/dl. Similarly, the serum-ascites albumin gradient levels were 2.89±0.65 in non malignant ascites patients, while the malignancy related ascites cases had 0.86±0.50. The discrimination values for cholesterol were taken as 45 mg/dl while that for serum ascites gradient was taken as 1.1. Levels of serum cholesterol, total protein and albumin were not significantly altered.  相似文献   
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Serum Adenosine deaminase (ADA) activity in normal healthy control subjects increases upto 30 years, remains steady between 31–60 years of age and shows a steep increase in the age group of 61–70 years. This was compared with serum aspartate transaminase (AST) and alanine transaminase (ALT) activity which also showed a gradual increase upto 40 years of age and decreased thereafter. The activities of serum ADA, AST and ALT increased in patients with hepatitis of all age groups compared to their respective controls. The degree of increase in the activities of the above enzymes in hepatitis, decreased with age. The present study also shows that while studying serum ADA activity in hepatitis for diagnostic purposes, the value obtained in a particular age group should be compared with normal range of values for the respective age group only.  相似文献   
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Satisfaction is a condition that contributes to the development of intrinsic motivation and a continuing motivation to learn. Research that helps to identify the factors that contribute to learning satisfaction is useful for educators. This paper introduces the Cognitive-Motivational Model of Decision Satisfaction, a model that extends Kruglanski's work on closure and builds on Keller's work on the motivational aspects of instruction and learning. Focusing on decision-making activities in a learning context, this model recognizes the importance of information-processing in judgmental tasks and specifies confidence as a major contributing factor to learning satisfaction. Some potential applications to both classroom and computer-based learning environments are suggested.  相似文献   
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