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61.
Introduction: The aim of this study is to evaluate prostate-specific antigen decline pattern including prostate-specific antigen kinetics following androgen deprivation therapy on prostate-specific antigen progression in the patients with advanced prostate cancer.

Materials and methods: Ninety-seven advanced prostate cancer patients receiving maximum androgen deprivation therapy were enrolled in case–control study. Baseline prostate-specific antigen, Gleason Score, bone metastase, nadir prostate-specific antigen, time to nadir prostate-specific antigen, declining slope to nadir prostate-specific antigen, estimated baseline prostate-specific antigen half-time, current prostate-specific antigen, post-nadir prostate-specific antigen time, estimated prostate-specific antigen, estimated decline of baseline prostate-specific antigen as quantitative, and ratio were recorded and calculated.

Results: The ratio of prostate-specific antigen progression was significantly lower at the patients who had slower declining slope to prostate-specific antigen, longer time to nadir prostate-specific antigen, and lower estimated decline ratio of baseline prostate-specific antigen (p: .016, p: .020, and p: .026, respectively).

Conclusions: The shorter time to nadir prostate-specific antigen following androgen deprivation therapy, faster declining slope to nadir prostate-specific antigen and higher estimated decline ratio of baseline prostate-specific antigen are associated with higher risk of disease progression in patients with hormone-sensitive prostate cancer.  相似文献   

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In this study, classical and robust principal component analyses are used to evaluate socioeconomic development of regions of development agencies that give service on the purpose of decreasing development difference among regions in Turkey. Due to the high differences between development levels of regions outlier problem occurs, hence robust statistical methods are used. Also, classical and robust statistical methods are used to investigate if there are any outliers in data set. In classic principal component analyse, the number of observations must be larger than the number of variables. Otherwise determinant of covariance matrix is zero. In Robust method for Principal Component Analysis (ROBPCA), a robust approach to principal component analyse in high-dimensional data, even if the number of variables is larger than the number of observations, principal components are obtained. In this paper, firstly 26 development agencies are evaluated with 19 variables by using principal component analysis based on classical and robust scatter matrices and then these 26 development agencies are evaluated with 46 variables by using the ROBPCA method.  相似文献   
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Previous research focuses on preventive maintenance strategies which minimize the costs of break downs and of maintenance activities. Deteriorating machine conditions with the consequence of rising scrap rates and declining productivity are mostly neglected. This paper investigates simultaneous optimization of production and maintenance planning by applying the condition-based maintenance strategy with parallel machines and overlapping capabilities. The presented model allows exploitation of machine wear considering optimal order assignments to machines which is illustrated by a numerical example.  相似文献   
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Many companies are increasingly making use of coaching as an instrument of human resources development. The selection of the a suitable coach is more often based on intuition of the selecting human resources employees than it is objective. This underscores the need for a more systematic approach to the selection of coaches, which is based on the useable competencies of a coach and is also scientifically supported. Through a multiparadigm literature review and an explorative study, this article identifies seven base competencies of coaches, which can serve as a foundation for the selection of a coach.  相似文献   
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The aim of this study was to assess the quality of occupational history information obtained via retrospective interview questions by comparison with occupational information for the same individuals obtained via a number of censuses. Moreover, morbidity patterns were investigated for different occupational exposure categories that were constructed either on occupational data gathered retrospectively or on data gathered longitudinally through censuses. The study population consisted of 6764 men and 2104 women who were interviewed within the Swedish Survey on Living Conditions. Census data on occupation from 1960, 1970 and 1975 were used for comparison. There was high level of agreement between the two data bases for occupational categories containing workers who were stable in their occupations. The correspondence was better for women. Prevalence rates for different long-term illnesses were almost the same for the categories, no matter which of the data bases was used for constructing the categories. Thus, we have found that self-reported work histories might be a useful way of controlling for occupational exposures in the past.  相似文献   
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AStA Advances in Statistical Analysis - We investigate the potential occurrence of change points—commonly referred to as “momentum shifts”—in the dynamics of football...  相似文献   
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Large pharmaceutical companies maintain a portfolio of assets, some of which are projects under development while others are on the market and generating revenue. The budget allocated to R&D may not always be sufficient to fund all the available projects for development. Much attention has been paid to the selection of optimal subsets of available projects to fit within the available budget. In this paper, we argue the need for a forward-looking approach to portfolio decision-making. We develop a quantitative model that allows the portfolio management to evaluate the need for future inflow of new projects to achieve revenue at desired levels, often aspiring to a certain annual revenue growth. Optimisation methods are developed for the presented model, allowing an optimal choice of number, timing and type of projects to be added to the portfolio. The proposed methodology allows for a proactive approach to portfolio management, prioritisation, and optimisation. It provides a quantitatively based support for strategic decisions regarding the efforts needed to secure the future development pipeline and revenue stream of the company.  相似文献   
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