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21.
T. Pradeep 《Resonance》1999,4(1):53-62
In recent years, a number of systems have been shown to spontaneously assemble on appropriate solid surfaces to form films with thicknesses of molecular dimensions. The special techniques needed to prepare, characterise and study such monolayers are described. The potential applications of these systems as catalysts, sensors, electrooptic and other materials are summarized.  相似文献   
22.
Osteoarthritis of knee joints is a disease of old age in both sex. It is very common after the age of 40 years in elderly females or in postmenopausal phase of females. It is characterized by narrowing of space in joints due to inflammation. The exact mechanism of inflammation in this disease is not yet clear. Tumor necrosis factor alpha (TNF-α) may involve in onset of disease. The present study is being carried out in 130 female subject of age group 40–60 years suffering from osteoarthritis of knee joints and 50 normal healthy control female subjects. A correlation is made between TNF-α and estrogen and found significant inverse correlation (r<0.001), between TNF-α and estrogen hormone in osteoarthritic female patients as compared to normal healthy control female group.  相似文献   
23.
Catechol-O-methyl transferase (COMT) enzyme catalyzes the metabolism of dopamine and other catechols in the brain. Several articles investigated catechol-O-methyltransferase (COMT) Val158Met polymorphism as risk factor for alcohol dependence (AD) but the results were inconclusive. The aim of present meta-analysis was to evaluate the association of Val158Met (COMT) polymorphism with AD. Authors performed keyword search of the 4 electronic databases—Pubmed, Google Scholar, Springer Link and Science Direct databases up to December 31, 2019. Total eighteen studies that investigated the association of Val158Met polymorphism with AD were retrieved. The pooled results from the meta-analysis (2278 AD cases and 3717 healthy controls) did not show association with AD using all 5 genetic models (allele contrast model: OR = 1.02, 95% CI = 0.90–1.14, p = 0.03; homozygote model: OR = 1.06, 95% CI = 0.81–1.38, p = 0.69; dominant model: OR = 0.99, 95% CI = 0.85–1.14, p = 0.87; co-dominant model: OR = 0.97, 95% CI = 0.86–1.11, p = 0.71; recessive model: OR = 1.05;95% CI = 0.85–1.29, p = 0.61). Results of subgroup analysis showed that Val158Met is not risk for AD in Asian and Caucasian population. In conclusion, COMT Val158Met is not a risk factor for alcohol dependence.  相似文献   
24.
Research Findings: This study explored the relationship between play and child development at the Grade 1 level. As previous research has noted a sudden curtailment of classroom play during this period, the relationship between play at home and children's school grades, behavior, and creativity scores was examined using correlational and regression analyses. In particular, this study sought to assess whether particular types of play (pretend play, active physical play, construction play, etc.) and social arrangements during play (play with siblings, with parents, alone, with friends) predicted any of the outcome measures. A total of 56 children ages 6 and 7 from suburban areas outside of Montreal, as well as their parents and teachers, participated in the study. Practice or Policy: Findings indicated that children spent between 1 and 2 hr playing after school each day and that the most common form of play was active physical play. The most common social arrangement during play was play with siblings. Children's free time in the morning and freedom to choose their play activities in the afternoon were predictive of children's academic progress. Watching others play and the ability to choose their own activities in the afternoon predicted positive adaptive behaviors at school. Play with commercial toys and playing alone were predictive of creativity scores.  相似文献   
25.
Three species of Mansonioides vectors viz.,Ma. annulifera, Ma. uniformis andMa. indiana were found in Cherthala taluk, Kerala which is one of the endemic areas due toB. malayi. The immatures of Mansonioides thrive mainly in association with macrophytic hydrophytes such asP. stratiotes, S. molesta andE. crassipes in perennial habitats (ponds, channels/ canals etc.,) andI. miliaceae in seasonal habitats (fallow lands etc.) Breeding potential was higher (130.19) in clean ponds withP. stratiotes, compared to that of polluted ones (40.69). However, the polluted habitats infested with the same host plants were found to be the most productive forMa. annulifera, with an average daily adult emergence rate of 601/100 sq.m.). The clean habitats played a major role in the contribution ofMa. uniformis, whereS. molesta in the perennial habitats and I. miliaceae in the seasonal fallow lands were the favourable plants contributing a daily output of 12.5/100 sq.m and 221.81/100 sq.m. respectively.E. crassipes infested polluted habitats formed the major source forMa. indiana, the emergence rate being 13.89/100 sq.m. The perennial habitats supported mainly the breeding ofMa. annulifera (70.82%), whereas the seasonal habitats contributed the major chunk ofMa. uniformis (92.54%) andMa. indiana (71.43%). The bionomics of Mansonioides mosquitoes are thus shown to be greatly influenced by the community structure of hydrophytes and also the nature of breeding habitats.  相似文献   
26.
Lead poisoning is well documented in persons occupationally exposed to lead. What is less known is, that even in persons working in lead based industries, the effect of lead and the appearance of signs and symptoms of lead poisoning is genetically determined. Three genes related to lead metabolism, exhibiting polymorphism have already been demonstrated-δALA-dehydratase, Vitamin D receptor gene and Hemochromatosis gene. These alleles determine the susceptibility of the individuals to lead. We present here a case of a lead acid battery worker, who presented without any signs and symptoms of lead poisoning except for a very high level of blood lead (82.8μg/dl and 47.5μg/dl 9 months later)  相似文献   
27.
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   
28.
Lipid abnormalities remain to be a major cause of early mortality in patients with chronic renal failure (CRF). In present study, 114 (one hundred fourteen) CRF patients without any additional cause of dyslipidemia were divided into groups on the basis of etiologies of CRF. Blood samples from each group were analyzed for total cholesterol, triglyceride and HDL cholesterol along with blood urea nitrogen and serum creatinine. 25 healthy individuals without any obvious disease were taken as control. Patients from all the groups showed a marked hypertriglyceridemia of 232 (SD±77) mg/dl (P<0.001) as compared to control. Levels of HDL cholesterol were found to be significantly low 20 (±11) mg/dl (p<0.001) in all the groups. LDL cholesterol showed an increase 104 (±30) mg/dl as compared to control group which is not statistically significant. Present study reveals that, CRF patients show an uniform dyslipidemia irrespective of etiologies leading to CRF. This dyslipidemia is also independent of serum creatinine levels. Although, these lipid abnormalities may not solely cause mortality in CRF patients, they may act as modulators in accelerating atherogenesis which in turn cause early mortality in CRF patients.  相似文献   
29.
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   
30.
Heavy metals are important toxicants known to exert adverse effects in humans and animals, given sufficient exposure and accumulation in the body. This has a great concern both at personal and public health risk. Heavy metals are also known to interact with the essential trace minerals at the level of absorption and also during the metabolism. The adverse effects of the absorbed and accumulated heavy metals include neurological, reproductive, renal and hematological systems. Children are more sensitive than adults to the effects of lead. Efforts are made to understand the mechanism of the interactions of heavy metals with essential trace minerals at the level of absorption. With available sensitive and specific methodologies like Anodic Stripping Voltammetry for the evaluation of the levels of toxic heavy metals such as lead, cadmium, mercury etc., better understanding of heavy metal absorption is made possible. Due to the poor nutritional standards, risk of heavy metal exposure is still a major concern in developing countries. Studies carried out by the author have provided evidence towards the understanding of the prevailing mechanisms of metal-metal interaction at the intestinal level. During growth and development the demand for the essential minerals being at higher level, differentiation of various essential metals and heavy metals pose an inherent problem due to certain common properties shared by them. With this approach to the problem of heavy metal toxicity, it is preventable not only with environmental intervention but also by the nutritional management.  相似文献   
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