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161.
Purpose: To compare the efficacy and safety of sildenafil 25?mg qd, 25?mg bid or 50?mg qd – on treating lower urinary tract symptoms with benign prostatic hyperplasia (LUTS/BPH).Materials and methods: Men aged?>?45 years with LUTS/BPH were randomly assigned to receive sildenafil 25?mg qd (n?=?42), bid (n?=?41), 50?mg qd (n?=?38) or placebo (n?=?41) for 8 weeks. Changes from baseline in International Prostate Symptom Score (I-PSS), maximum urinary flow rate (Qmax) and postvoid residual urine volume (PVR) were assessed at week 4 and week 8.Results: Sildenafil 25?mg qd (-7.3?±?5.8) and 25?mg bid (-7.0?±?5.7) exhibited significant improvements of I-PSS compared to placebo (-5.2?±?6.4) (p?=?0.020, 0.025, respectively). In particular, voiding domain was more affected than storage domain. Only sildenafil 50?mg qd improved nocturia significantly (versus placebo, p?=?0.027). Quality of life score was improved in all treatment groups. Qmax and PVR did not change significantly in all groups. All regimens were well tolerated.Conclusions: Sildenafil 25?mg qd, 25?mg bid and 50?mg qd are safe and effective to improve LUTS/BPH in long term, along with coexisting ED. In particular, nocturia is most well-controlled by 50?mg qd. 相似文献
162.
163.
Covariate measurement error problems have been extensively studied in the context of right‐censored data but less so for current status data. Motivated by the zebrafish basal cell carcinoma (BCC) study, where the occurrence time of BCC was only known to lie before or after a sacrifice time and where the covariate (Sonic hedgehog expression) was measured with error, the authors describe a semiparametric maximum likelihood method for analyzing current status data with mismeasured covariates under the proportional hazards model. They show that the estimator of the regression coefficient is asymptotically normal and efficient and that the profile likelihood ratio test is asymptotically Chi‐squared. They also provide an easily implemented algorithm for computing the estimators. They evaluate their method through simulation studies, and illustrate it with a real data example. The Canadian Journal of Statistics 39: 73–88; 2011 © 2011 Statistical Society of Canada 相似文献
164.
Death ideation and death anxiety represent the cognitive and affective dimensions of death attitudes, respectively. General beliefs about the world are proposed to be useful defensive mechanisms protecting persons against the death anxiety provoked by death ideation. SEM is employed to test the proposed mediation model, using a sample of 133 Hong Kong Chinese university students. Results showed that death ideation was significantly and inversely linked to belief in social cynicism, reward for application, and fate control. Moreover, higher levels of belief in fate control and lower levels of religiosity predicted greater death anxiety. Only belief in fate control partially mediated the relationship between death ideation and death anxiety. Discussion focused on how social axioms serve as useful defensive mechanisms against death anxiety. 相似文献
165.
Hahn (1977) suggested a procedure for constructing prediction intervals for the difference between the means of two future samples from normal populations having equal variance, based on past samples selected from both populations. In this paper, we extend Hahn's work by constructing simultaneous prediction intervals for all pairwise differences among the means of k ≥ 2 future samples from normal populations with equal variances, using past samples taken from each of the k populations. For K = 2, this generalization reduces to Hahn's special case. These prediction intervals may be used when one has sampled the performance of several products and wishes to simultaneously as- sess the differences in future sample mean performance of these products with a predetermined overall coverage probability. The use of the new procedure is demonstrated with a numerical example. 相似文献
166.
Ying-Chao Hung 《Journal of statistical planning and inference》2012,142(1):86-94
We consider the bandit problem with an infinite number of Bernoulli arms, of which the unknown parameters are assumed to be i.i.d. random variables with a common distribution F. Our goal is to construct optimal strategies of choosing “arms” so that the expected long-run failure rate is minimized. We first review a class of strategies and establish their asymptotic properties when F is known. Based on the results, we propose a new strategy and prove that it is asymptotically optimal when F is unknown. Finally, we show that the proposed strategy performs well for a number of simulation scenarios. 相似文献
167.
This article proposes a bivariate generalization of the noncentral negative binomial distribution which arises as a model in photon and neural counting. This bivariate generalization is derived as a mixed shifted bivariate negative binomial distribution. Various properties and parameter estimation, especially by a minimum distance method based on the probability generating function, are considered. To show the practical usefulness of the bivariate distribution proposed, an application to model low-flux astronomical images is discussed and a real data set has been analyzed. 相似文献
168.
In this paper the rank method for forced discrimination in two population problems, introduced by Randies, Broffitt, Ramberg and Hogg (1978), is extended to cover settings involving more than two populations. Several methods of ranking are compared to the normal theory procedure in a Monte Carlo study. Asymptotic theory is included which confirms that the rank method does balance the limiting probabilities of misclassification in a two population setting. 相似文献
169.
In this paper, we introduce a precedence-type test based on Kaplan–Meier estimator of cumulative distribution function (CDF) for testing the hypothesis that two distribution functions are equal against a stochastically ordered hypothesis. This test is an alternative to the precedence life-test proposed first by Nelson (1963). After deriving the null distribution of the test statistic, we present its exact power function under the Lehmann alternative, and compare the exact power as well as simulated power (under location-shift) of the proposed test with other precedence-type tests. Next, we extend this test to the case of progressively Type-II censored data. Critical values for some combination of sample sizes and progressive censoring schemes are presented. We then examine the power properties of this test procedure and compare them to those of the weighted precedence and weighted maximal precedence tests under a location-shift alternative by means of Monte Carlo simulations. Finally, we present two examples to illustrate all the test procedures discussed here, and then make some concluding remarks. 相似文献
170.
Yung Sik Kim 《East Asian Science, Technology and Society: An International Journal》2010,4(2):207-228
In this essay, I will provide a preliminary overview of the relation between the Confucian scholars and the specialized scientific
and technical knowledge in traditional China. I will begin by analyzing various elements in the historical background of traditional
China that had various different effects on the scholars' attitudes to the specialized knowledge—classical Confucian ideas
and phrases, practical reasons, etc. I will then look at the actual examples showing the varying relations between the Confucian
scholars and the specialized knowledge. I will end with a comparative look at the situation in the West, where there were
developments both for separation and for convergence between general scholars and specialized scientific and technical knowledge.
I will show that the relation, on the whole, was ambivalent in traditional China. Although there was some kind of separation
of scholars from the specialized scientific and technical knowledge, the separation was not clear cut, and there was no solid
ground for such separation; at times, there were convergences between the two. There was a wide spectrum of attitude among
the Confucian scholars toward the specialized knowledge, varying according to different individuals, different periods, and
different subjects. 相似文献