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141.
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   
142.
Hormones play an important role in the development and regulation of reproductive function and the menstrual cycle of women. Extremes of body weight tend to affect the homeostasis of the hypothalamo–pituitary–gonadal axis. This cross-sectional study was carried out in 113 women (57 with primary infertility and 56 with secondary infertility) in the age group 20–35 years, presenting for hormonal evaluation of infertility in a tertiary care hospital. After preliminary clinical evaluation, anthropometric indices (height, weight, BMI, waist circumference and waist hip ratio) were measured in all subjects. Fasting blood sample drawn on second/third day of menstrual cycle was analysed for serum luteinizing hormone, follicle stimulating hormone (FSH), prolactin and thyroid stimulating hormone (TSH). Serum FSH levels showed a significant positive correlation with indicators of central obesity (waist circumference and waist hip ratio in both the study groups). In primary infertility, significant positive correlation was also observed between serum FSH levels and other markers of obesity like body weight, hip circumference and BMI. In secondary infertility, serum prolactin and serum TSH levels demonstrated a significant positive correlation with body weight and BMI. Obesity is associated with hormonal derangements which are responsible for infertility. In overweight women with infertility, weight loss should be considered as a first line treatment.  相似文献   
143.
Reactive oxygen species, as singlet oxygen (1O2), is continuously being generated by aerobic organisms, and react actively with biomolecules. At excessive amounts, 1O2 induces oxidative stress and shows carcinogenic and toxic effects due to oxidation of lipids, proteins and nucleic acids. In our study, immunoglobulin G (IgG) was modified by 1O2 generated by the ultraviolet (UV) irradiation of methylene blue. The modified IgG was characterized by UV spectroscopy, carbonyl content determination, thermal denaturation and electrophoretic study. Oxidation induced by modification of IgG by 1O2 also analyzed by scavenging studies. It was found that ultraviolet absorption spectra of modified IgG shows marked hyperchromicity. The carbonyl content was found to be high in modified IgG as compared to native IgG which confirms its oxidation. Thermal denaturation of modified protein sample shows decrease in Tm value by 3 °C and less intensity banding pattern on polyacrylamide gel electrophoresis. The quenching effect of sodium azide provides clue for modification of IgG by methylene blue, as it is known 1O2 scavenger. Hence, the IgG modified with 1O2 may be one of the etiological pathogenic factors for rheumatoid arthritis and diabetes.  相似文献   
144.
145.
DISASTER RECOVERY PLANNING FOR TELECOMMUNICATIONS by Leo A. Wrobel (Boston: Artech House, 1990—price not given, ISBN 0-89006-460-1,112 pp.)

LONG DISTANCE SERVICES: A BUYER'S GUIDE by Daniel D. Briere (Boston: Artech House, 1990—price not given, ISBN 0-89006-439-3,293 pp.)

ADVANCES IN TELECOMMUNICATIONS MANAGEMENT edited by Jagdish Sheth and Garly Frazier (Greenwich, CT: JAI Press, 1990—$63.50 each, ISBN as listed below)

MANAGING THE R&D/MARKETING INTERFACE FOR PRODUCT SUCCESS: THE TELECOMMUNICATIONS FOCUS edited by Massoud Saghafi and Ashok K. Gupta (1990—ISBN 1-55938-144-2,218 pp.)

PURCHASING IN THE 1990S: THE EVOLUTION OF PROCUREMENT IN THE TELECOMMUNICATIONS INDUSTRY edited by Wesley J. Johnston (1990—ISBN 1-55938-145-0,257 pp.)  相似文献   
146.
The purpose of this paper is to provide concrete illustrations of the efficacy of the multiple regression approach to the analysis of experimental results. A bridge between theoretical and specific applications is provided by parallel multiple regression and analysis of variance solutions for two typical educational designs. Detailed illustrations are given in the techniques of writing linear constraints and determining degrees of freedom. The major advantages of the multiple regression approach are its adaptability to unusual designs and the facilitation of meaningful interpretation afforded by the provision of regression weights in addition to the usual Fratios.  相似文献   
147.
Abstract

The author conducted a study with early childhood educators in New Delhi to understand the teachers’ perceptions of the relationship between their preparation and practice within a theory‐practice framework. The research problem emanated from the observations and experiences of the author, indicating an existing three‐way tension between the design of current Indian teacher education programs, the dominant discourse of early childhood education, and the underlying values of Indian philosophy that defined the construct of the teacher and child in Indian society.  相似文献   
148.
Abstract

The aim of this study was to investigate the convergent and predictive validity of two skill tests that examine the ability of golfers to hit accurate approach-iron shots. Twenty-four high-level golfers (handicap = 2.6 ± 1.7) performed the Nine-Ball Skills Test (assesses the ability to shape/control ball trajectory with high accuracy) and the Approach-Iron Skill Test (assesses the ability to hit straight shots from varying distances with high accuracy). Participants then completed at least eight rounds of tournament golf over the following 90 days and reported an indicator of approach-iron accuracy (per cent error index). A moderate correlation (r = 0.50, P < 0.05) was noted between scores for both tests. Generalised estimating equations, using two covariates (lie of the ball and distance to hole), were used to determine model fit and the amount of variance explained for tournament per cent error index. Results showed that the Approach-Iron Skill Test was the slightly stronger predictor of on-course per cent error index. With both test scores considered together, a minimal amount of additional variance was explained. These findings suggest that either of the tests used individually or combined may be used to predict tournament approach iron performance in high-level golfers.  相似文献   
149.
There is considerable research work on the performance assessment of eGovernment projects, especially on performance assessment measures per se. The point that the authors in this paper make is that while a variety of performance assessment measures are important for evaluation of eGovernment projects, performance itself is intended to relate governance with eGovernment applications. Thus, while developing performance assessment measures, there is a need to be conscious of governance as the ultimate purpose. Taking the Indian Police Administration as its domain, this paper demonstrates how performance assessment can be so conceived as to help capture the impact of eGovernment in regard to implications for governance in the given domain.  相似文献   
150.
This article presents an analysis of the way art is conceptualised in the British primary school curriculum and provides an historical framework that maps an evolution of ideas that have shaped the way art is presented in the modern day primary curriculum. In order to achieve this a Foucauldian style genealogical analysis is utilised to trace the discourses (systems of meaning) surrounding the nature of children's artistic development and how these discourses are used in the present day British primary curriculum to construe art in different ways. The analysis in this article is threefold. It explores the presentation of art in the curriculum as (1) an expressive subject, (2) a skills based subject, (3) a subject which focuses on art history and art appreciation. Second, the teaching positions associated with each approach are identified as follows (a) the facilitator, (b) the expert and (c) the philosopher; as well as the issues teachers face when adopting these positions. Third, attention is given to how these theoretical principles might be linked to practice. In so doing this article contributes to the debate surrounding the value of art in the primary curriculum and the way in which the curriculum serves to shape teaching practice.  相似文献   
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