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31.
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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Discrimination and memory for video films of women performing different activities was investigated in 5.5 month-old infants. In Experiment 1, infants (N = 24) were familiarized to the faces of one of three women performing one of three repetitive activities (blowing bubbles, brushing hair, and brushing teeth). Overall, results indicated discrimination and memory for the actions but not the faces after both a 1-min and a 7-week delay. Memory was demonstrated by a visual preference for the novel actions after the 1-min delay and for the familiar actions after the 7-week delay, replicating prior findings that preferences shift as a function of retention time. Experiment 2 (N = 12) demonstrated discrimination and memory for the faces when infants were presented in static poses at the 1-min delay, but not the 7-week delay. In Experiment 3 (N = 18), discrimination of the actions was replicated, but no discrimination among the objects embedded in the actions (hairbrush, bubble wand, toothbrush) was found. These findings demonstrate the attentional salience of actions over faces in dynamic events to 5.5 month-olds. They highlight the disparity between results generated from moving versus static displays in infancy research and emphasize the importance of using dynamic events as a basis for generalizing about perception and memory for events in the real world. 相似文献
34.
A healthy civil society has long been held as vital to a healthy democracy and there is interest in whether the Internet affects this linkage. This paper explores the relationships between offline and online modes of associational life and also analyzes offline and online interactions with local governments in the US context. Based on our empirical analyses of 1,203 respondents, we show that online participation is not simply an extension of offline participation, but can be distinguished in important ways. First, we find that political and community-oriented engagements cluster separately from more private-regarding engagements. Second, participants of online democratic engagement are not characterized by the SES markers associated with offline democratic engagement who are older, have higher incomes, and have lived in the community longer. Finally, we find significant links between democratic engagement with the political system and involvement with political associations (but not social and community-oriented associations). 相似文献
35.
Recently, the model of adoption of technology in households (MATH) was developed and tested in the context of household personal computer (PC) adoption. In this study, we apply MATH to predict personal computer (PC) use. We conducted a nationwide survey including 370 households that owned at least one PC. Results indicate that attitudinal beliefs are extremely important in determining use of a PC in the household. In contrast to previous work examining adopters, normative and control beliefs were not significant in predicting use. Furthermore, several determinants of adoption that were important at different stages of the household life cycle were found nonsignificant in predicting use for the same stages of the household life cycle. Overall, the results demonstrate that the belief structure for household PC use is different from that of household PC adoption. Further, the results provide additional evidence regarding the importance of including household life cycle in studies of household technology adoption and use. 相似文献
36.
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
37.
Pradeep Venkatesh Garg Satpal Lalit Verma Tewari Hem Kumar Sheena Garg 《Indian journal of clinical biochemistry : IJCB》2001,16(1):9-14
Antioxidants are a small group of substances that protect living cells from the destructive consequences of powerful oxidizing
intermediates that can be formed from oxygen. Situations in which pro-oxidant mechanisms within the body are more active than
the antioxidant mechanisms (oxidative stress) predispose and contribute to the pathogenesis of several ailments in various
organs of the body. In the eye, pro-oxidant factors have been blamed for the causation of diseases such as age related macular
degeneration and senile cataract. The role of pro-oxidants in the genesis of certain diseases is well established however,
the effectivity of antioxidants provided to the body by dietary supplementation is inconclusive. In this article we provide
a review on the basic concepts of antioxidant-pro-oxidant interaction in relation to its effects on the eye. 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
40.
LIU Ai-jun FURUSATO Bungo RAVINDRANATH Lakshmi CHEN Yong-mei SRIKANTAN Vasanta MCLEOD David G. PETROVICS Gyorgy SRIVASTAVA Shiv 《Journal of Zhejiang University. Science. B》2007,8(12):853-859
Objective: To investigate molecular alterations associating with prostate carcinoma progression and potentially provide information toward more accurate prognosis/diagnosis. Methods: A set of laser captured microdissected (LCM) specimens from 300 prostate cancer (PCa) patients undergoing radical prostatectomy (RP) were defined. Ten patients representing "aggressive" PCa, and 10 representing "non-aggressive" PCa were selected based on prostate-specific antigen (PSA) recurrence, Gleason score, pathological stage and tumor cell differentiation, with matched patient age and race between the two groups. Normal and neoplastic prostate epithelial cells were collected with LCM from frozen tissue slides obtained from the RP specimens. The expressions of a panel of genes, including NPY, PTEN, AR, AMACR, DD3, and GSTP1, were measured by quantitative real-time RT-PCR (TaqMan), and correlation was analyzed with clinicopathological features. Results: The expressions of AMACR and DD3 were consistently up-regulated in cancer cells compared to benign prostate epithelial cells in all PCa patients, whereas GSTP1 expression was down regulated in each patient. NPY, PTEN and AR exhibited a striking difference in their expression patterns between aggressive and non-aggressive PCas (P=0.0203, 0.0284, and 0.0378, respectively, Wilcoxon rank sum test). The lower expression of NPY showed association with "aggressive" PCas based on a larger PCa patient cohort analysis (P=0.0037, univariate generalized linear model (GLM) analysis). Conclusion: Despite widely noted heterogeneous nature of PCa, gene expression alterations ofAM,4CR, DD3, and GSTP1 in LCM-derived PCa epithelial cells suggest for common underlying mechanisms in the initiation of PCa. Lower NPY expression level is significantly associated with more aggressive clinical behavior of PCa; PTEN and AR may have potential in defining PCa with aggressive clinical behavior. Studies along these lines have potential to define PCa-associated gene expression alterations and likely co-regulation of genes/pathways critical in the biology of PCa onset/progression. 相似文献