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Yan-Hong Zhang Vydianathan Ravi Geng Qin He Dai Hui-Xian Zhang Feng-Ming Han Xin Wang Yu-Hong Liu Jian-Ping Yin Liang-Min Huang Byrappa Venkatesh Qiang Lin 《国家科学评论(英文版)》2020,7(6):964
Syngnathids (seahorses, pipefishes and seadragons) exhibit an array of morphological innovations including loss of pelvic fins, a toothless tubular mouth and male pregnancy. They comprise two subfamilies: Syngnathinae and Nerophinae. Genomes of three Syngnathinae members have been analyzed previously. In this study, we have sequenced the genome of a Nerophinae member, the Manado pipefish (Microphis manadensis), which has a semi-enclosed brood pouch. Comparative genomic analysis revealed that the molecular evolutionary rate of the four syngnathids is higher than that of other teleosts. The loss of all but one P/Q-rich SCPP gene in the syngnathids suggests a role for the lost genes in dentin and enameloid formation in teleosts. Genome-wide comparison identified a set of 118 genes with parallel identical amino acid substitutions in syngnathids and placental mammals. Association of some of these genes with placental and embryonic development in mammals suggests a role for them in syngnathid pregnancy. 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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D'souza HS Dsouza SA Menezes G Venkatesh T 《Indian journal of clinical biochemistry : IJCB》2011,26(2):197-201
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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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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K. C. Vasudha A. Nirmal Kumar T. Venkatesh 《Indian journal of clinical biochemistry : IJCB》2006,21(1):116-120
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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The practical viability of performance-based pay programs for teachers depends critically on the extent of support the idea will receive from teachers. We present evidence on teacher opinions with regard to performance-based pay from teacher interviews conducted in the context of an experimental evaluation of a program that provided performance-based bonuses to teachers in the Indian state of Andhra Pradesh. We report four main findings in this paper: (1) over 80% of teachers had a favorable opinion about the idea of linking a component of pay to measures of performance, (2) exposure to an actual incentive program increased teacher support for the idea, (3) teacher support declines with age, experience, training, and base pay, and (4) the extent of teachers’ stated ex ante support for performance-linked pay (over a series of mean-preserving spreads of pay) is positively correlated with their ex post performance as measured by estimates of teacher value addition. This suggests that teachers are aware of their own effectiveness and that implementing a performance-linked pay program could not only have broad-based support among teachers but also attract more effective teachers into the teaching profession. 相似文献