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241.
阻塞性睡眠呼吸暂停综合征(obstructive sleep apnea hypopnea syndrome,OSAHS)是一种常见的睡眠呼吸紊乱性疾病,以睡眠时反复发作的上气道部分或完全阻塞为特征。近年发现OSAHS与2型糖尿病之间有着明显的相关性,二者均为心血管疾病的高危因素,合并存在能够严重影响生命质量与预期寿命...  相似文献   
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The aim of this study was to examine the effects of histaminergic antagonists on memory upon injection into the region of the nucleus basalis magnocellularis (NBM). In experiment 1, rats with chronically implanted cannulae were trained on the uphill avoidance task, which involves a punishment of a high-probability turning response on a tilted platform (negative geotaxis). Immediately after the training trial, that is, after a tail shock was administered upon performing the response, rats received one microinjection (0.5 microliter) of H1-receptor blocker chlorpheniramine (dose range 0.1 to 20 microgram) or the H2-receptor blocker ranitidine (same dose range) or saline into the NBM region. When tested 24 h later, rats treated with chlorpheniramine (20 micrograms) had significantly longer uphill latencies than vehicle controls and ranitidine-treated animals, indicative of superior learning of the avoidance response. In experiment 2, a test for possible proactive effects of posttrial chlorpheniramine on performance during the retention trial was performed. Animals were injected with either 20 micrograms chlorpheniramine or saline immediately after the training trial of the uphill task. One chlorpheniramine control group was treated with a delay of 5 h. Additional groups which received chlorpheniramine or vehicle after the training trial but no trail shock were included. When tested 24 h later, rats injected with 20 micrograms chlorpheniramine again exhibited significantly longer uphill latencies than did vehicle-injected rats. Retention latencies for the rats of the chlorpheniramine 5-h delayed group did not differ from those of the vehicle-injected rats, ruling out proactive effects of chlorpheniramine on performance. In summary, the histaminergic H1-blocker chlorpheniramine can enhance mnemonic functioning in addition to its reinforcing effects upon NBM injection as reported previously.  相似文献   
245.
采用事件相关电位技术(ERPs),用条件性习得范式探讨厌恶与恐惧情绪习得的性别差异。行为结果表明,在成功习得厌恶、恐惧和中性情绪之后,男女性在唤醒度维度上,性别差异显著;脑电结果表明,在早期N1和P2成分,厌恶情绪与恐惧情绪的习得无显著性别差异;但男女不同性别在N2成分上差异显著,主要表现为女性在厌恶、恐惧、中性这三类CS的N2成分均差异显著,但男性仅厌恶与中性情绪的CS差异显著。结果表明在负性情绪的习得中,女性比男性更敏感。  相似文献   
246.
Jordi Valor Abad 《Synthese》2008,160(2):183-202
Proponents of the explanatory gap claim that consciousness is a mystery. No one has ever given an account of how a physical thing could be identical to a phenomenal one. We fully understand the identity between water and H2O but the identity between pain and the firing of C-fibers is inconceivable. Mark Johnston [Journal of philosophy (1997), 564–583] suggests that if water is constituted by H2O, not identical to it, then the explanatory gap becomes a pseudo-problem. This is because all “manifest kinds”—those identified in experience—are on a par in not being identical to their physical bases, so that the special problem of the inconceivability of ‘pain = the firing of C-fibers’ vanishes. Moreover, the substitute relation, constitution, raises no explanatory difficulties: pain can be constituted by its physical base, as can water. The thesis of this paper is that the EG does not disappear when we substitute constitution for identity. I examine four arguments for the EG, and show that none of them is undermined by the move from constitution to identity.  相似文献   
247.
William Craig 《Synthese》2008,164(3):321-332
A common aim of elimination problems for languages of logic is to express the entire content of a set of formulas of the language, or a certain part of it, in a way that is more elementary or more informative. We want to bring out that as the languages for logic grew in expressive power and, at the same time, our knowledge of their expressive limitations also grew, elimination problems in logic underwent some change. For languages other than that for monadic second-order logic, there remain important open problems.  相似文献   
248.
This article defends a regulative ethics of voluntary belief. In order to determine the occasion and the scope of such an ethics, the article begins with an examination of the concept of belief in conversation with the view of J. L. Schellenberg. Next, against the dominant position in contemporary epistemology, it argues that some beliefs can be voluntary, in the sense that they are under the immediate control of the believer, and replies to William Alston’s influential objections to doxastic voluntarism. If some beliefs are subject to the immediate control of the believer, then in these cases believers are ethically responsible not only for how they investigate those beliefs, but also for the choice of whether or not to believe them. The article concludes by formulating and defending two types of regulative ethical principles governing voluntary belief.  相似文献   
249.
为了探讨MMP-2、TIMP-1在DMEH和DN发病中的意义,随机收集T2DM患者146例,其中SDM 57例,DMEH 38例,DN 51例,健康对照38例。用ELISA法测定MMP-2、TIMP-1的含量。结果显示,DM患者尤其是DMEH和DN患者血清MMP-2明显低于健康对照组,P均〈0.01,且随病情发展呈逐渐降低趋势。而血清TIMP-1随病情的发展则呈现明显的上升趋势,SDM、DMEH组和DN组与健康对照组比较,分别为P〈0.05,P〈0.01和P〈0.01。因此,MMP-2和TIMP-1可能参与了DMEH和DN的发生发展过程,定期检测DM患者血清MMP-2和TIMP-1的含量变化有助于DM并发症的早期诊断和疗效观察。  相似文献   
250.
Four experiments were conducted to examine social and emotional memory in the R6/2 transgenic mouse model of Huntington’s disease. First, R6/2 mice were tested in a social transmission of food preference task where they had to acquire a preference for a flavoured food (acquisition) and subsequently to learn a preference for a different flavour (shifted reinforcement). R6/2 mice performed well in the acquisition trial. However, they were impaired in the shifted reinforcement trial and perseverated on the first preference learned. Second, mice were trained in an inhibitory avoidance paradigm, with either one or two footshocks delivered during the training. WT mice given one footshock showed retention levels lower than those of mice trained with two footshocks. By contrast, there was no difference in retention levels of R6/2 mice given either one or two footshocks. Third, mice were tested in an active avoidance task that paired a mild footshock with a warning light. R6/2 mice had a strong age-dependent deficit in this task. Finally, mice were tested in a conditioned taste aversion task that paired a saccharine solution with a nausea-inducing agent (LiCl). R6/2 mice displayed normal aversion, however this was not extinguished following repeated exposure to saccharine solution alone. Our data show that while R6/2 mice have functional hippocampus-based memory, they have deficits in striatum-based memory skills. Further, social and emotional memories appear to be encoded in a rigid way that is not influenced by subsequent learning or by arousal levels.  相似文献   
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