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51.
Genome-wide association studies have discovered multiple single nucleotide polymorphisms (SNPs) associated with the risk of common diseases. The objective of this study was to demonstrate the replication of previously published SNPs that showed statistical significance for breast cancer in the Malaysian population. In this case–control study, 80 subjects for each group were recruited from various hospitals in Malaysia. A total of 768 SNPs were genotyped and analyzed to distinguish risk and protective alleles. A total of three SNPs were found to be associated with increased risk of breast cancer while six SNPs showed protective effect. All nine were statistically significant SNPs (p ≤ 0.01), five SNPs from previous studies were successfully replicated in our study. Significant modifiable (diet) and non-modifiable (family history of breast cancer in first degree relative) risk factors were also observed. We identified nine SNPs from this study to be either conferring susceptibility or protection to breast cancer which may serve as potential markers in risk prediction.

Electronic supplementary material

The online version of this article (doi:10.1007/s12291-013-0414-0) contains supplementary material, which is available to authorized users.  相似文献   
52.
Despite enormous research in the field of hypertension, its pathophysiology still remains largely unresolved and appears to be multifactorial. In the present communication, we have analyzed the status of nitric oxide (NO) in the patients with essential hypertension and age matched controls. We have found that the levels of NO are lowered in essential hypertension. The normalization of blood pressure by administration of antihypertensive therapy causes rise in the NO level indicating that perturbed NO status in essential hypertension is reversible. Addition of antioxidant to the antihypertensive drugs causes a further, though non significant, rise in the levels of NO, suggesting that antioxidants may be combined with antihypertensive drugs as adjunct in the management of essential hypertension.  相似文献   
53.
This study, employing hierarchical linear modeling (HLM), sought to investigate the student-level and school-level factors associated with the science achievement of immigrant and non-immigrant students among a national sample of 22,646 students from 896 schools in Canada. While student background characteristics such as home language, family wealth, and socioeconomic status were significant predictors of science achievement for non-immigrant students, these factors were not significantly associated with immigrant student science achievement. Student attitudes, engagement, and motivation in science and information and communication technology familiarity were significant predictors of science achievement for both immigrant and non-immigrant students. Whereas teacher shortage was associated with science achievement for immigrant students, school size was associated with science achievement for non-immigrant students. Implications of the findings are discussed.  相似文献   
54.
Background:?Students’ motivation is known to influence academic outcomes. However, there is a paucity of research showing the relative influences of motivational factors on short-term and long-term outcomes.

Purpose:?The study investigates the relative influences of motivational factors – mastery goal orientation, value of schooling, and academic self-concepts (perceived competence in and affect to schoolwork) on four outcomes – rule acceptance, identity, general self-efficacy and achievement.

Sample:?Students in grades 3 to 6 from six primary schools in the Sydney were surveyed (N = 979). The ages of the participants varied from 8 to 13 years (mean = 9.78).

Design and methods:?Students completed a questionnaire and literacy and numeracy achievement tests. Structural equation modelling was used to examine the paths from four predictors to four outcomes.

Results:?Whereas all four predictors were positively associated with all four outcomes, students’ mastery goal had stronger positive influences on self-efficacy and identity. Value, perceived competence and affect were found to influence outcomes in different ways – positive influences were found for value on achievement, rule-acceptance, and identity; for perceived competence on achievement and efficacy; and for affect on rule-acceptance and identity.

Conclusion:?Mastery goal had stronger influences on long-term outcomes while other predictors are stronger for short-term outcomes. To facilitate short-term and long-term outcomes, all four motivational factors need attention.  相似文献   
55.
The study was planned to assess the prevalence of thyroid disorders in type 2 diabetes in North Indian population and to correlate the serum insulin and glycosylated haemoglobin levels with thyroid hormones. It is a case control study. One hundred and twenty patients of type 2 diabetes were included in the study along with 117 adults of the same age group and normal glucose levels as controls. All blood samples were taken from subjects who fasted for at least 12 h before the blood collection. Glycosylated hemoglobin was determined by ion exchange chromatography and serum insulin and thyroid hormones were assessed through enzyme linked immunosorbent assay. Fasting blood glucose and glycosylated haemoglobin levels were significantly higher in diabetics showing a poor glucose control. Serum tri-iodothyronine values were significantly lower in diabetics. There was a significant correlation between glycosylated haemoglobin and thyroid hormones. There was no correlation between serum insulin and thyroid hormones.  相似文献   
56.
Reactive oxygen species (ROS) cause damage to the DNA producing mutations and formation of tumours such as carcinoma of breast. Tumour cells are known to produce ROS at a greater pace than the non-transformed cells. The increased production of reactive oxygen species causes oxidative stress leading to cell proliferation and hence increased inflammatory conditions. The present study was aimed to investigate the role of oxidative stress in the pathogenesis of breast cancer. Females suffering from breast cancer had significantly decreased Superoxide dismutase (SOD) and reduced glutathione (GSH) levels in comparison to normal females. The compromised antioxidant defence system produces the oxidative stress which in turn creates the inflammatory response shown by concomitant increased adenosine deaminase (ADA) activity in female patients. ADA diminishes the protective molecule adenosine. There were significant variations (p < 0.01) in ADA activity with different clinical stages (stage 1–4) of breast cancer suggesting thereby that estimation of ADA activity can be used as a diagnostic tool to detect the stage of cancer along with cytological studies. Mastectomy was performed and post-operatively serum SOD and ADA activity and plasma GSH levels were estimated. There was a statistically significant increase in activity of SOD and levels of GSH while serum ADA activity decreased significantly, suggesting thereby that oxidative stress is responsible for increased cell proliferation and hence the inflammatory conditions in CA breast that got ameliorated post-operatively.  相似文献   
57.
Big Data Analytics (BDA) is increasingly becoming a trending practice that generates an enormous amount of data and provides a new opportunity that is helpful in relevant decision-making. The developments in Big Data Analytics provide a new paradigm and solutions for big data sources, storage, and advanced analytics. The BDA provide a nuanced view of big data development, and insights on how it can truly create value for firm and customer. This article presents a comprehensive, well-informed examination, and realistic analysis of deploying big data analytics successfully in companies. It provides an overview of the architecture of BDA including six components, namely: (i) data generation, (ii) data acquisition, (iii) data storage, (iv) advanced data analytics, (v) data visualization, and (vi) decision-making for value-creation. In this paper, seven V's characteristics of BDA namely Volume, Velocity, Variety, Valence, Veracity, Variability, and Value are explored. The various big data analytics tools, techniques and technologies have been described. Furthermore, it presents a methodical analysis for the usage of Big Data Analytics in various applications such as agriculture, healthcare, cyber security, and smart city. This paper also highlights the previous research, challenges, current status, and future directions of big data analytics for various application platforms. This overview highlights three issues, namely (i) concepts, characteristics and processing paradigms of Big Data Analytics; (ii) the state-of-the-art framework for decision-making in BDA for companies to insight value-creation; and (iii) the current challenges of Big Data Analytics as well as possible future directions.  相似文献   
58.
59.
This article aims to explore the symptoms and characteristics of dyscalculia. This is a qualitative study. Five experts in the field of special education took part in a focus group interview. Each expert had more than ten years of experience in their area of expertise. To determine the content validity of the protocol, three experts in special education, language and qualitative research evaluated each of the eight items. Cohen's kappa analysis was used to assess inter-rater reliability. The findings of this study indicate that 59 items have been developed, based on six constructs in the dyscalculia checklist. The six constructs were subitising, estimating, Arabic numerals, verbal numbers, arithmetic facts and calculating processes. Following the focus group interview, a new construct emerged: math anxiety. The study implies that teachers might utilise this checklist to carry out early detection of students with dyscalculia in primary schools. This will enable appropriate intervention, resulting in significant benefits for the Ministry of Education, for educators and teachers, and for the students themselves. Although this study was based in Malaysia, the results have wider implications because dyscalculia is present everywhere.  相似文献   
60.
Traditionally Friedewald formula has been used to calculate low density lipoprotein cholesterol (LDL-C) concentration though now direct homogenous methods for its measurement are also available. Clinical guidelines recommend the use of calculated LDL-C to guide therapy because the evidence base for cholesterol management is derived almost exclusively from trials that use calculated LDL, with direct measurement of LDL-C being reserved for those patients who are non fasting or with significant hypertriglyceridemia. In this study our aim was to compare calculated and direct LDL and their variation at different cholesterol and triglyceride levels. Fasting lipid profile estimation was done on 503 outpatients in a tertiary hospital. Both direct and calculated LDL were then compared. Mean fasting direct LDL was found to be higher than calculated LDL in 87.1 % of subjects by 8.64 ± 8.35 mg/dl. This difference was seen a all levels of cholesterol and triglyceride. Using 130 mg/dl LDL cholesterol as cut off fewer subjects were classified as high risk by calculated LDL than direct LDL. In conclusion, direct LDL is higher than calculated LDL. Compared with direct measurement, the Friedewald calculation underestimates the risk for ischemic heart disease.  相似文献   
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