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71.
Onder Canguven Raidh A. Talib Walid El-Ansari Ahmed Shamsoddini Mahmoud Salman Abdulla Al-Ansari 《The aging male》2016,19(4):215-220
Background: Late-onset hypogonadism (LOH) presents with low serum testosterone (TT) levels and sexual and nonsexual symptoms. Erectile dysfunction affects a man’s self-esteem and as a result partner relationship and quality of life.Objectives: To investigate the andrological clinical profile outcomes of testosterone therapy (TTh) in men (n?=?88) with symptomatic LOH complaints and symptoms.Main outcome measures: Erectile function was assessed using the International Index of Erectile Function-5 questionnaire at baseline and at 6 and 12 months of TTh. In addition, penile length was measured at baseline and 12 months. We also evaluated nocturnal penile tumescence (NPT, using RigiScan) and blood flow of cavernous arteries (penile Doppler ultrasonography) at baseline and 12 months of TT.Materials and methods: Eighty-eight LOH men (Mage 51.1 years) with erectile dysfunction, all with serum TT?<10.4?nmol/L before TTh. Patients received intramuscular long-acting testosterone undecanoate for 12 months.Results: Following TTh, in all patients, serum TT levels were restored within 3 months to normal levels. Compared with baseline values, erectile function significantly improved at 6 (mean score increase 1.95) and 12 months (mean score increase 2.16). No significant changes in penile length were observed. NPT significantly improved at 12 months in terms of both the frequency (mean increase 1.27 times) and duration of rigidity (mean increase 5.12?min). As regards the blood flow of the cavernous arteries, we observed a significant improvement (decrease of 1.16?cm/s) and end diastolic velocity of the penile arteries.Conclusion: TTh in men with LOH resulted in improvement of the erectile function, NPT, and to some extent the blood flow of the cavernous arteries. 相似文献
72.
Joseph A. Schwartz Mohammed Said Al-Ghamdi Ahmed Nezar Kobeisy Fathiyah H. Alqurashi Eric J. Connolly Kevin M. Beaver 《International Journal of Social Welfare》2017,26(3):263-275
Relatively few studies have attempted to identify factors that contribute to variation in parental behavior. The literature has revealed associations between both internal and external factors in the variation in parenting behaviors. In addition, the vast majority of the existing literature has focused almost exclusively on Western cultures (e.g., the USA). The current study addresses these limitations by examining direct and indirect pathways involving both internal and external sources of influence on parenting behaviors in a sample of adults from Saudi Arabia (N = 196). The employed statistical models revealed robust and consistent direct associations between the examined internalizing sources of influence (self-control and psychopathy) and parenting behaviors. Subsequent models revealed some evidence of mediation stemming from external sources of influence (namely, aggression). However, the resulting indirect effects were inconsistent, indicating that other, unmeasured mechanisms ultimately connect the examined internalizing problems and parenting behaviors. 相似文献
73.
Ahmed Shafik M.D. 《Journal of sex research》2013,50(2):153-157
A recently identified reflex, termed the “cervico‐motor reflex,” was studied in 15 healthy women (mean age 36.6 years). The response of levator ani (LA) and puborectalis (PR) muscles to electrical and mechanical stimulation of the cervix uteri (CU) was determined. One concentric needle electrode was inserted into the CU (stimulating), a second into the LA (recording), and a third into the PR (recording). The vaginal pressure was measured at rest and on cervical stimulation by balloon‐tipped catheters. Electrical stimulation of the CU led to a reduction in pressure in the upper portion of the vagina (p < .05) and an increase in pressure in the middle and lower portions (p < .001). Stimulation also caused an increase in the electromyographic (EMG) activity of the LA and PR muscles (p < .01). Mechanical stimulation induced the same effects but to a lesser degree. Stimulation of the anesthetized CU, LA, or PR did not evoke the response. The data suggested the presence of a reproducible reflex relationship between the CU and both the LA and PR. During the sexual act and penile buffeting of the CU, levator contraction “balloons” the upper vagina, which acts as a “receptacle” for the semen. Meanwhile, PR contraction narrows the lower vagina, which may effect an increase of penile erection and rigidity. The cervico‐motor reflex may be incorporated as an investigative tool in sexual act disorders. 相似文献
74.
Ahmed Bawa Kuyini Abdul Razak Alhassan Inga Tollerud† Hanne Weld† Iddi Haruna† 《Child & Family Social Work》2009,14(4):440-449
Surveys were employed to explore the experiences of children in care and their carers about traditional fostering. They also examined the perspectives of randomly selected adults in the community about the practice of traditional foster care in the Tamale area of northern Ghana. The 74 participants responded to closed- and open-ended interview questions about traditional foster care. Frequencies and thematic grouping of qualitative responses showed that the need to keep family ties alive was the key reason for placement of children with family and kin. Majority of the children expressed satisfaction with living in foster care, even though they had experienced physical and emotional abuse and intimidation. Although most carers were not formally employed and had little personal income, they were positive about having the care role, but faced challenges in providing for many children in a difficult economic situation. The report highlights the role of reciprocity, altruistic and socio-cultural factors in quality of care, and the potential for the traditional kinship foster care to provide suitable avenues of placement for children as recommended by the Ghana child rights law. It also identifies the need for education for carers around children's needs and Ghana's child rights law. 相似文献
75.
The estimation of the reliability function of the Weibull lifetime model is considered in the presence of uncertain prior information (not in the form of prior distribution) on the parameter of interest. This information is assumed to be available in some sort of a realistic conjecture. In this article, we focus on how to combine sample and non-sample information together in order to achieve improved estimation performance. Three classes of point estimatiors, namely, the unrestricted estimator, the shrinkage estimator and shrinkage preliminary test estimator (SPTE) are proposed. Their asymptotic biases and mean-squared errors are derived and compared. The relative dominance picture of the estimators is presented. Interestingly, the proposed SPTE dominates the unrestricted estimator in a range that is wider than that of the usual preliminary test estimator. A small-scale simulation experiment is used to examine the small sample properties of the proposed estimators. Our simulation investigations have provided strong evidence that corroborates with asymptotic theory. The suggested estimation methods are applied to a published data set to illustrate the performance of the estimators in a real-life situation. 相似文献
76.
Ahmed A. Soliman Ahmed H. Abd Ellah Naser A. Abou-Elheggag Abdullah A. Modhesh 《Journal of Statistical Computation and Simulation》2013,83(12):2270-2290
In this paper, a new life test plan called a progressively first-failure-censoring scheme introduced by Wu and Ku? [On estimation based on progressive first-failure-censored sampling, Comput. Statist. Data Anal. 53(10) (2009), pp. 3659–3670] is considered. Based on this type of censoring, the maximum likelihood (ML) and Bayes estimates for some survival time parameters namely reliability and hazard functions, as well as the parameters of the Burr-XII distribution are obtained. The Bayes estimators relative to both the symmetric and asymmetric loss functions are discussed. We use the conjugate prior for the one-shape parameter and discrete prior for the other parameter. Exact and approximate confidence intervals with the exact confidence region for the two-shape parameters are derived. A numerical example using the real data set is provided to illustrate the proposed estimation methods developed here. The ML and the different Bayes estimates are compared via a Monte Carlo simulation study. 相似文献
77.
This article considers the shrinkage estimation procedure in the Cox's proportional hazards regression model when it is suspected that some of the parameters may be restricted to a subspace. We have developed the statistical properties of the shrinkage estimators including asymptotic distributional biases and risks. The shrinkage estimators have much higher relative efficiency than the classical estimator, furthermore, we consider two penalty estimators—the LASSO and adaptive LASSO—and compare their relative performance with that of the shrinkage estimators numerically. A Monte Carlo simulation experiment is conducted for different combinations of irrelevant predictors and the performance of each estimator is evaluated in terms of simulated mean squared error. Simulation study shows that the shrinkage estimators are comparable to the penalty estimators when the number of irrelevant predictors in the model is relatively large. The shrinkage and penalty methods are applied to two real data sets to illustrate the usefulness of the procedures in practice. 相似文献
78.
S.E. Ahmed 《统计学通讯:理论与方法》2013,42(3):771-789
The problem of estimating the Poisson mean is considered based on the two samples in the presence of uncertain prior information (not in the form of distribution) that two independent random samples taken from two possibly identical Poisson populations. The parameter of interest is λ1 from population I. Three estimators, i.e. the unrestricted estimator, restricted estimator and preliminary test estimator are proposed. Their asymptotic mean squared errors are derived and compared; parameter regions have been found for which restricted and preliminary test estimators are always asymptotically more efficient than the classical estimator. The relative dominance picture of the estimators is presented. Maximum and minimum asymptotic efficiencies of the estimators relative to the classical estimator are tabulated. A max-min rule for the size of the preliminary test is also discussed. A Monte Carlo study is presented to compare the performance of the estimator with that of Kale and Bancroft (1967). 相似文献
79.
The heteroscedasticity consistent covariance matrix estimators are commonly used for the testing of regression coefficients when error terms of regression model are heteroscedastic. These estimators are based on the residuals obtained from the method of ordinary least squares and this method yields inefficient estimators in the presence of heteroscedasticity. It is usual practice to use estimated weighted least squares method or some adaptive methods to find efficient estimates of the regression parameters when the form of heteroscedasticity is unknown. But HCCM estimators are seldom derived from such efficient estimators for testing purposes in the available literature. The current article addresses the same concern and presents the weighted versions of HCCM estimators. Our numerical work uncovers the performance of these estimators and their finite sample properties in terms of interval estimation and null rejection rate. 相似文献
80.
Ahmed El Ghini 《统计学通讯:理论与方法》2013,42(21):4651-4661
For the class of autoregressive-moving average (ARMA) processes, we examine the relationship between the dual and the inverse processes. It is demonstrated that the inverse process generated by a causal and invertible ARMA (p, q) process is a causal and invertible ARMA (q, p) model. Moreover, it is established that this representation is strong if and only if the generating process is Gaussian. More precisely, it is derived that the linear innovation process of the inverse process is an all-pass model. Some examples and applications to time reversibility are given to illustrate the obtained results. 相似文献