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81.
Objective: This study set out to assess effects of testosterone replacement therapy (TRT) on parameters of metabolic syndrome and vascular function in obese hypogonadal males with type 2 diabetes mellitus (DM2).

Study design: Fifty-five obese hypogonadal diabetic males on oral hypoglycemic treatment were enrolled into this one-year, double-blind, randomized, placebo-controlled clinical study. Group T (n?=?28) was treated with testosterone undecanoate (1000?mg i.m. every 10?weeks) while group P (n?=?27) received placebo.

Methods: Anthropometrical and vascular measurements – flow-mediated dilatation (FMD) and intima media thickness (IMT) – biochemical and hormonal blood sample analyses were performed at the start of the study and after one year. Derived parameters (BMI, HOMA-IR, calculated free testosterone (cFT) and bioavailable testosterone (BT)) were calculated.

Results: TRT resulted in reduction of HOMA-IR by 4.64?±?4.25 (p?p?p?=?.005).

Conclusion: TRT normalized serum testosterone levels, improved glycemic control and endothelial function while exerting no ill effects on the study population.  相似文献   
82.
Introduction: Tadalafil is a promising phosphodiesterase (PDE) 5 inhibitor prescribed for erectile dysfunction (ED). Daily low dose (5?mg) of tadalafil has also been used for the treatment of male lower urinary tract symptoms (LUTS) associated with benign prostate hyperplasia (BPH). PDE5 inhibitors induce relaxation of smooth muscle cells in the urethra, prostate, bladder neck, and blood vessels. The aim of this study was to investigate the efficacy of tadalafil on vessels endothelial function, in patients with male LUTS symptoms associated with BPH.

Methods: The Institutional Review Board (IRB) approved this clinical study and informed consents had been obtained from 81 BPH patients.

The following male LUTS parameters: international prostate symptom score (IPSS), overactive bladder symptom score (OABSS), voiding volume, max and mean voiding flow on voiding flowmetry examination and post-voiding residual urine (RU) were compared at 0, 1, 3, 6, and 12 months after a daily dose of 5?mg tadalafil.

In addition, erectile function was evaluated by the sexual health inventory for men (SHIM) score and vessels endothelial function and peripheral neuropathy were assessed by the brachial-ankle pulse wave velocity (baPWV), ankle brachial index (ABI), and vibration perception threshold (VPT) at 0, 3, 6, and 12 months after treatment.

Results: The mean age of 81 patients was 66.4?±?11.4 years old. Their prostate size was 30.2?±?22.1?ml.

Male LUTS parameters including IPSS, OABSS, and RU showed significant improvement from 1 to 12 months after tadalafil administration. Max and mean voiding flow was significantly increased at 6 months after tadalafil treatment.

The SHIM score showed significant improvement after 3 months. Whilst, the results of baPWV also showed significant improvement from 3 to 12 months. ABI was also significantly improved at 6 months. However, there was no change in the VPT at any time point.

Conclusions: Tadalafil is effective for both male LUTS and ED. It is also shown that tadalafil improves baPWV, which we can conclude that higher vessels elasticity has been obtained. This major finding of this study shows that tadalafil has the potency to improve vessels endothelial dysfunction in patients with BPH.  相似文献   
83.
In the past few years, the Lindley distribution has gained popularity for modeling lifetime data as an alternative to the exponential distribution. This paper provides two new characterizations of the Lindley distribution. The first characterization is based on a relation between left truncated moments and failure rate function. The second characterization is based on a relation between right truncated moments and reversed failure rate function.  相似文献   
84.
We develop testing procedures which detect if the observed time series is a martingale difference sequence. Furthermore, tests are developed that detect change–points in the conditional expectation of the series given its past. The test statistics are formulated following the approach of Fourier–type conditional expectations first proposed by Bierens (1982 Bierens, H. J. (1982). Consistent model speci?cation tests. J. Econometr. 20:105134.[Crossref], [Web of Science ®] [Google Scholar]) and have the advantage of computational simplicity. The limit behavior of the test statistics is investigated under the null hypothesis as well as under alternatives. Since the asymptotic null distribution contains unknown parameters, a bootstrap procedure is proposed in order to actually perform the test. The performance of the bootstrap version of the test is compared in finite samples with other methods for the same problem. A real–data application is also included.  相似文献   
85.
The paper investigates various nonparametric models including regression, conditional distribution, conditional density and conditional hazard function, when the covariates are infinite dimensional. The main contribution is to prove uniform in bandwidth asymptotic results for kernel estimators of these functional operators. Then, the application issues, involving data-driven bandwidth selection, are discussed.  相似文献   
86.
Statistical inference for the diffusion coefficients of multivariate diffusion processes has been well established in recent years; however, it is not the case for the drift coefficients. Furthermore, most existing estimation methods for the drift coefficients are proposed under the assumption that the diffusion matrix is positive definite and time homogeneous. In this article, we put forward two estimation approaches for estimating the drift coefficients of the multivariate diffusion models with the time inhomogeneously positive semidefinite diffusion matrix. They are maximum likelihood estimation methods based on both the martingale representation theorem and conditional characteristic functions and the generalized method of moments based on conditional characteristic functions, respectively. Consistency and asymptotic normality of the generalized method of moments estimation are also proved in this article. Simulation results demonstrate that these methods work well.  相似文献   
87.
ABSTRACT

This study investigated racial and ethnic differences in home modification use. Data from the 2011 National Health and Aging Trends Study were used (n=6,764). Compared with non-Hispanic Whites, Hispanics were less likely to have a grab bar (odds ratio (OR) = 0.6), bath seat (OR = 0.8), or raised toilet (OR = 0.6). Non-Hispanic Blacks were less likely to have a grab bar (OR = 0.7) or bath seat (OR = 0.7) than non-Hispanic Whites, but more likely to have a raised toilet (OR = 1.3). English proficiency largely explained ethnic differences, while health status partially accounted for racial disparities.  相似文献   
88.
The varying coefficient (VC) model introduced by Hastie and Tibshirani [26 T. Hastie and R. Tibshirani, Varying-coefficient models, J. R. Statist. Soc. (Ser. B) 55 (1993), pp. 757796.[Web of Science ®] [Google Scholar]] is arguably one of the most remarkable recent developments in nonparametric regression theory. The VC model is an extension of the ordinary regression model where the coefficients are allowed to vary as smooth functions of an effect modifier possibly different from the regressors. The VC model reduces the modelling bias with its unique structure while also avoiding the ‘curse of dimensionality’ problem. While the VC model has been applied widely in a variety of disciplines, its application in economics has been minimal. The central goal of this paper is to apply VC modelling to the estimation of a hedonic house price function using data from Hong Kong, one of the world's most buoyant real estate markets. We demonstrate the advantages of the VC approach over traditional parametric and semi-parametric regressions in the face of a large number of regressors. We further combine VC modelling with quantile regression to examine the heterogeneity of the marginal effects of attributes across the distribution of housing prices.  相似文献   
89.
This paper establishes a remarkable result regarding Palm distributions for a log Gaussian Cox process: the reduced Palm distribution for a log Gaussian Cox process is itself a log Gaussian Cox process that only differs from the original log Gaussian Cox process in the intensity function. This new result is used to study functional summaries for log Gaussian Cox processes.  相似文献   
90.
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