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91.
Summary Both thermal and nociceptive stimulation in the periphery were shown to influence the neuronal activity recorded in the striatal area. Both the thermal and nociceptive sensitivity of the striatal neurons were closely related.The authors are grateful to the Alexander von Humboldt-Stiftung (Bad Godesberg, Bonn, Federal Republic of Germany) for donations of the necessary equipment for the present study. The research reported here was supported by grants from the National Science Council (Taipei, Taiwan, Republic of China) 相似文献
92.
根据入口区域长度的定义,应用解析法研究了一个界定血管入口长度的方法.分析了刚性的及弹性的等截面圆直血管和圆锥形直血管的定常流动、非定常振荡流动等多种流动情况下的入口区域长度 相似文献
93.
对血管脉动流模拟实验提出了一种新型的计算机控制系统和数据处理系统.着重论述了这一系统的原理、功能和实施控制的各种软件处理方法. 相似文献
94.
在挤出机上安装自行设计的毛细管口模,对PP,HDPE和PS熔体采用挤出物胀大法在较高剪切速率下测量第一法向应力差N_1,发现:由于N_1受胀大比B和剪切应力τ_W的双重影响,因此弹性测试比粘性测试所需的毛细管口模长径比要大;将挤出物胀大法与其他测量N_1的方法进行综合的分析比较,结果表明,挤出物胀大法所测N_1值比较合理,并可满足一般工程计算的要求。 相似文献
95.
L. Yin C. M. Chung R. Huo H. Liu C. Zhou W. Xu H. Zhu J. Zhang Q. Shi H. Y. C. Wong J. Chen Y. Lu Y. Bi C. Zhao Y. Du M. Ma Y. Cai W. Y. Chen K. L. Fok L. L. Tsang K. Li Y. Ni Y. W. Chung Z. Zhou J. Sha H. C. Chan 《Cellular and molecular life sciences : CMLS》2009,66(5):900-908
The acrosome reaction has long been thought to be induced by the zona pellucida. Here we report the identification and function
of a novel human sperm glycosylphosphatidylinositol (GPI)-anchored membrane protein, NYD-SP8. The release of the protein during
sperm-egg interaction and its binding to the cumulus, the first layer of egg investment, elicits cross-talk between the gametes
and produces calcium dependant release of progesterone, which lead to the acrosome reaction. An in vivo mouse model of NYD-SP8 immunization is also established showing a reduced fertility rate. Thus, contrary to accepted dogma,
our study demonstrates for the first time that, prior to reaching the zona pellucida, sperm may release a surface protein
that acts on the cumulus cells leading to the acrosome reaction, which may be important for determining the outcome of fertilization.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Received 11 August 2008; received after revision 18 December 2008; accepted 22 December 2008 相似文献
96.
以3-氯丙烯、苯酚、甲醛和苯胺为原料,制备了烯丙基苯并噁嗪及其中间体烯丙基苯基醚、邻烯丙基苯酚.探讨了原料比、反应温度、反应时间对产物收率的影响.结果表明,邻烯丙基苯酚与苯胺、甲醛反应物质的量之比为1∶1∶2、反应温度为80℃、反应6 h时,烯丙基苯并噁嗪的收率可达到98.8%. 相似文献
97.
The study of endophenotypes may be a viable strategy to tackle the genetic complexity and phenotypic heterogeneity of psychosis, but this research direction is relatively under-developed in China as compared to Western countries. We have recently initiated one of the first family studies of endophenotypes for psychosis in China. Patients entering an established early psychosis intervention service are recruited into this research project for phenotyping, endophenotyping and genotyping. At the endophenotypic... 相似文献
98.
A mean square error criterion is proposed in this paper to provide a systematic approach to approximate a long‐memory time series by a short‐memory ARMA(1, 1) process. Analytic expressions are derived to assess the effect of such an approximation. These results are established not only for the pure fractional noise case, but also for a general autoregressive fractional moving average long‐memory time series. Performances of the ARMA(1,1) approximation as compared to using an ARFIMA model are illustrated by both computations and an application to the Nile river series. Results derived in this paper shed light on the forecasting issue of a long‐memory process. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
99.
There has been growing interest in exploiting potential forecast gains from the nonlinear structure of self‐exciting threshold autoregressive (SETAR) models. Statistical tests have been proposed in the literature to help analysts check for the presence of SETAR‐type nonlinearities in observed time series. However, previous studies show that classical nonlinearity tests are not robust to additive outliers. In practice, time series outliers are not uncommonly encountered. It is important to develop a more robust test for SETAR‐type nonlinearity in time series analysis and forecasting. In this paper we propose a new robust nonlinearity test and the asymptotic null distribution of the test statistic is derived. A Monte Carlo experiment is carried out to compare the power of the proposed test with other existing tests under the influence of time series outliers. The effects of additive outliers on nonlinearity tests with misspecification of the autoregressive order are also studied. The results indicate that the proposed method is preferable to the classical tests when the observations are contaminated with outliers. Finally, we provide illustrative examples by applying the statistical tests to three real datasets. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
100.
It is easy to apply lines in design drawings to create different styles, however, there is no guarantee that all the style lines drawn are able to be manufactured. In this paper, we focus on one undeliverable style to enhance our understanding of the relationship between the design sketch and the pattern design process. In order to evidence that such style is unworkable, a systematic display of pattern development, and to be reinforced by mathematical evaluation, will be introduced and addressed. When one can easily detect design fault, waste of product development time can be minimized. 相似文献