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41.
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   
42.
CD40-CD40L interaction plays a significant role in the pathogenesis of atherosclerosis and coronary artery disease. The clinical predictive value of Soluble CD40 Ligand (sCD40L) was evaluated in patients with Acute Coronary Syndrome (ACS) and Non-Cardiac Chest Pain (NCCP). The levels of serum soluble CD 40 ligand were measured by ELISA in 485 patients admitted to emergency care unit, of which 89 patients were diagnosed as NCCP. The levels of sCD40L were significantly increased in patients with ACS when compared to controls and NCCP. Receiver Operator Characteristic (ROC) Curve analysis showed sCD40L to be a good discriminator between patients with ischemic heart disease and patients without ischemic heart disease. The area under the curve was found to be 0.940 with 95% CI (0.915 to 0.960) (P<0.0001). The cut off value from the ROC curve was 2.99 ng/ml, above which sCD40L was considered to be positive. Combined assessment of sCD40L, Troponin I and CK-MB enhanced the risk prediction and early classification of patients. sCD40L seems to be a promising biomarker for identification and risk stratification for patients with acute coronary syndrome.  相似文献   
43.
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   
44.
Metaphor is ubiquitous as a persuasion device although the process by which its effects are achieved is still not yet fully understood. The study proposes that the trope's persuasive outcomes derive from an emergent structural match between linguistic and conceptual metaphor that produces coherence among the structural components of attitude; a literal-only message offers no such match and hence by comparison less attitude coherence. To test this proposition, four hypotheses related to metaphor's effect on attitude and intra-attitudinal structural coherence were tested by manipulating message type (metaphor vs. literal), knowledge of metaphor target/attitude object (low vs. high), and placement of metaphor/literal equivalent (message introduction vs. conclusion). Results provided moderate support for the predictions.  相似文献   
45.
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   
46.
Antibodies against human leucocyte antigens (HLA) in sera from uni and multiparous women are the potential source of HLA reagent. The present study was undertaken to screen 169 sera from pregnant women for the presence of HLA antibodies employing 26 panel cells (Peripheral blood lymphocytes) having known HLA phenotypes. 20.7% (35/169) sera were found to be positive for HLA class-1 antibodies. Present study generated one monospecific, (r=0.6 for A32) the duospecific sera (r=0.5 for A2 B35, r=0.47 A1 DR6 and r=0.7 A28 B51), and rest multispecific sera (r=below 0.4). These positive sera will be utilized as HLA reagents in future studies for tissue typing.  相似文献   
47.
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   
48.
Routine investigations of a 70 year old male led to provisional diagnosis of anemia. However further investigations suggested the possibilities of carcinoma of stomach associated with pernicious anemia, multiple myeloma and megaloblastic anemia. Finally serum protein electrophoresis supported by the clinical suspicion confirmed multiple myeloma.  相似文献   
49.
Medical schools have reduced the time allotted to anatomy instruction. Consequently, schools engage students in more independent settings using information and communication technologies (ICT). There has been limited research in the use of video aids, a type of ICT, to enhance anatomy examination performance. The objective of this study is to describe the design, usage, and effect on examination performance of eight locally developed instructional anatomy videos. First‐year UCSF medical students (n = 141) had access to the videos. They reported their video usage, reason for usage, and satisfaction. The prior year students (n = 141) served as a historical control group. Anatomy and radiology examination performance was compared between groups while controlling for prior performance. The students with and without access to the videos did not differ in examination performance. Sixty‐one (43%) students in the experimental group responded to the survey. Of these, 79% reported using at least one video, viewing an average of 4.75 of the eight videos. They watched 3.27 (SD = 1.57, range 1–5) of the five anatomy videos and 1.48 (SD = 1.35; range 0–3) of the three radiology videos. In a regression analysis controlling for age and MCAT scores, using the anatomy videos at least once improved anatomy examination performance by 3.4% (P‐value = 0.007). There was no relationship between radiology video usage and radiology exam score. Video resource availability did not enhance student performance in anatomy and radiology. However, when analyzing performance for those whom we knew level of video use, there was a statistically different and higher anatomy achievement. Anat Sci Ed, 2008. © 2008 American Association of Anatomists.  相似文献   
50.
Liver transplantation is an accepted therapy for chronic liver disease patients. These patients generally have low levels of fat soluble vitamins, which have important antioxidant roles. Therefore, this study was undertaken to investigate whether such patients had evidence of antioxidant depletion and increased lipid peroxidation before transplant and whether the subsequent ischemia and reperfusion encountered during liver transplantation have any effect on antioxidant levels and lipid peroxidation. We assessed plasma total antioxidant capacity and serum lipid peroxide in 12 patients undergoing liver transplantation and equal numbers of healthy subjects. We found that before reperfusion, antioxidant levels were significantly decreased along with significantly elevated lipid peroxidation levels as compared with healthy controls (P<0.001). On reperfusion of the liver graft, further declined values of total antioxidant accompanied with highly elevated lipid peroxidation were seen than those of pre-reperfusion samples (P<0.001). This data shows that patients undergoing liver transplant have lowered antioxidant defenses and evidence of free radical damage, which compound the additional insult of reperfusion injury. Therefore antioxidant therapy in these patients before transplantation may ameliorate the effects of reperfusion.  相似文献   
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