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81.
莎拉·布莱曼是当代著名跨界音乐女高音歌唱家之一。她以独特的演唱风格和舞台艺术魅力风靡世界,推动了西方古典音乐传播。文章着眼于她独特的演唱风格和舞台艺术表演,从跨界音乐的角度入手,分析并诠释了诸多西方古典声乐作品。这些声乐作品在她的演唱下由本位的高深难懂,转为通俗化被广大听众所接受。在西方古典音乐传播的过程和流行音乐商业化不断发展的当代环境下,她的演唱形式开拓了一条大众审美和社会音乐需求的西方古典音乐传播道路。  相似文献   
82.

Background:

Inducible or neuronal nitric oxide synthase gene deletion increases or decreases anxiety-like behavior in mice, respectively. Since nitric oxide and endocannabinoids interact to modulate defensive behavior, the former effect could involve a compensatory increase in basal brain nitric oxide synthase activity and/or changes in the endocannabinoid system. Thus, we investigated the expression and extinction of contextual fear conditioning of inducible nitric oxide knockout mice and possible involvement of endocannabinoids in these responses.

Methods:

We evaluated the effects of a preferential neuronal nitric oxide synthase inhibitor, 7-nitroindazol, nitric oxide synthase activity, and mRNA changes of nitrergic and endocannabinoid systems components in the medial prefrontal cortex and hippocampus of wild-type and knockout mice. The effects of URB597, an inhibitor of the fatty acid amide hydrolase enzyme, which metabolizes the endocannabinoid anandamide, WIN55,212-2, a nonselective cannabinoid agonist, and AM281, a selective CB1 antagonist, on contextual fear conditioning were also evaluated.

Results:

Contextual fear conditioning expression was similar in wild-type and knockout mice, but the latter presented extinction deficits and increased basal nitric oxide synthase activity in the medial prefrontal cortex. 7-Nitroindazol decreased fear expression and facilitated extinction in wild-type and knockout mice. URB597 decreased fear expression in wild-type and facilitated extinction in knockout mice, whereas WIN55,212-2 and AM281 increased it in wild-type mice. Nonconditioned knockout mice showed changes in the mRNA expression of nitrergic and endocannabinoid system components in the medial prefrontal cortex and hippocampus that were modified by fear conditioning.

Conclusion:

These data reinforce the involvement of the nitric oxide and endocannabinoids (anandamide) in stress-related disorders and point to a deregulation of the endocannabinoid system in situations where nitric oxide signaling is increased.  相似文献   
83.
Many factors interact to influence threat perception and the subsequent experience of pain. This study investigated the effect of observing pain (extrinsic threat) and intrinsic threat of pain to oneself on pressure pain threshold (PPT). Forty socially connected pairs of healthy volunteers were threat-primed and randomly allocated to experimental or control roles. An experimental pain modulation paradigm was applied, with non-nociceptive threat cues used as conditioning stimuli. In substudy 1, the extrinsic threat to the experimental participant was observation of the control partner in pain. The control participant underwent hand immersion in noxious and non-noxious water baths in randomized order. Change in the observing participant's PPT from baseline to mid- and postimmersion was calculated. A significant interaction was found for PPT between conditions and test time (F2,78?=?24.9, P?<?.005). PPT increased by 23.6%?±?19.3% between baseline and during hand immersion (F1,39?=?43.7, P?<?.005). Substudy 2 investigated threat of imminent pain to self. After a 15-minute break, the experimental participant's PPT was retested (“baseline 2”). Threat was primed by suggestion of whole arm immersion in an icier, larger water bath. PPT was tested immediately before anticipated arm immersion, after which the experiment ended. A significant increase in PPT between “baseline 2” and “pre-immersion” was seen (t?=??7.6, P?=?.005), a pain modulatory effect of 25.8?±?20.7%. Extrinsic and intrinsic threat of pain, in the absence of any afferent input therefore influences pain modulation. This may need to be considered in studies that use noxious afferent input with populations who show dysfunctional pain modulation.

Perspective

The effect on endogenous analgesia of observing another's pain and of threat of pain to oneself was investigated. Extrinsic as well as intrinsic threat cues, in the absence of any afferent input, increased pain thresholds, suggesting that mere threat of pain may initiate analgesic effects in traditional noxious experimental paradigms.  相似文献   
84.
通过对以麻黄和石膏为主要配伍的经方进行分析,归纳麻黄与石膏的主要配伍规律。认为麻黄与石膏既可相互制约,又可相互为用,通过剂量的调整和方中其他辅助药物的加减变化,二者配伍应用可以实现发汗清热兼顾、以发汗为主和以清热为主等不同治疗目的。  相似文献   
85.
痛风是嘌呤代谢异常致使尿酸合成增加而导致的代谢性疾病,西药如秋水仙碱等用于痛风的治疗临床疗效确实可靠,但伴有一定的副作用而使其使用受到了限制,中药和天然药物用于治疗痛风具有疗效确切,安全,不良反应小等优势。笔者通过查阅近年来国内外的有关文献,重点从单方和经方、经验方等方面阐述中医药治疗痛风的研究进展,以期为抗痛风新药的开发提供科学依据。  相似文献   
86.
Although allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a curative approach for patients with acute myeloid leukemia (AML), relapse is a common occurrence. Several strategies, such as choice of conditioning regimen, donor lymphocyte infusions, pharmacologic agents, and cellular therapy approaches, are currently being developed to improve transplantation outcomes. This review outlines some important interventions and considerations to lower the burden of post-transplantation relapse in AML.  相似文献   
87.
Allogeneic hematopoietic stem-cell transplantation (HSCT) for chronic granulomatous disease (CGD) with a reduced-intensity conditioning regimen can be expected to lead to less therapy-related mortality and late-onset impairment, whereas it has also been reported to increase the risk of unsustained mixed donor chimerism and late rejection after transplantation. Herein, we report a 4-year-old boy with CGD who was successfully treated with unrelated bone marrow transplantation with a reduced-intensity conditioning regimen (RIC). Fludarabine-based RIC, 4 Gy of total body irradiation, 120 mg/kg of cyclophosphamide, and 125 mg/m2 of fludarabine, was adopted for transplantation, followed with 8.9 × 108/kg mononucleated donor cells infused without T-cell depletion. Although hematopoietic engraftment was rapidly obtained by day +17, he developed unstable donor chimerism. After tacrolimus withdrawal, the patient showed grade III acute graft-versus-host disease (GVHD), and subsequently reached full donor chimerism by day +61. Twelve months post-transplant, the patient has remained well with stable and durable engraftment, 100% donor chimerism, and normal superoxide production, without the requirement of donor lymphocyte infusions (DLI).  相似文献   
88.
Two experiments examined competition between an instrumental avoidance response and a Pavlovian safety signal for association with omission of electric shock in a human fear conditioning paradigm. Self-reported shock expectancies and skin conductance responses were consistent with blocking of learning of the instrumental contingency by prior training of the Pavlovian contingency, and vice versa. The results support the idea that a common learning mechanism underlies both Pavlovian and instrumental conditioning. The expectancy data suggest that this learning mechanism is cognitive in nature, and that Pavlovian and instrumental learning involve external and internal attributions, respectively. The procedure may thus serve as a laboratory model for attributional processes involved in the acquisition of threat expectancies in anxiety and anxiety disorders.  相似文献   
89.
Previous studies have shown that individuals with anxiety disorders exhibit deficits in fear inhibition and excessive generalization of fear, but little data exist on individuals at risk from these disorders. The present study examined the role of trait anxiety in the acquisition and generalization of fear in 126 healthy participants selected on the basis of their trait-anxiety scores. Measures of conditioning included fear-potentiated startle, skin conductance response and online risk ratings for the unconditioned stimulus. Contrary to our hypotheses, trait anxiety did not have any effect either on the acquisition or the generalization of fear. Our results suggest that these fear conditioning processes are not impaired in individuals at risk from anxiety.  相似文献   
90.
Trait anxiety, a stable personality trait associated with increased fear responses to threat, is regarded as a risk factor for the development and maintenance of anxiety disorders. Although the effect of trait anxiety has been examined with regard to explicit threat cues, little is known about the effect of trait anxiety on contextual threat learning. To assess this issue, extreme groups of low and high trait anxiety underwent a contextual fear conditioning protocol using virtual reality. Two virtual office rooms served as the conditioned contexts. One virtual office room (CXT+) was paired with unpredictable electrical stimuli. In the other virtual office room, no electrical stimuli were delivered (CXT−). High-anxious participants tended to show faster acquisition of startle potentiation in the CXT+ versus the CXT− than low-anxious participants. This enhanced contextual fear learning might function as a risk factor for anxiety disorders that are characterized by sustained anxiety.  相似文献   
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