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181.
Pain is a complex biological phenomenon that encompasses intricate neurophysiological, behavioural, psychosocial and affective components. Protracted or chronic pain alerts an individual to a possible pathological abnormality and is the main reason why patients visit a primary care physician. Despite the pervasiveness of chronic pain in the population, the effectiveness of current pharmacological therapies remains woefully inadequate and prolonged treatment often leads to the development of undesirable side-effects. Since the vast majority of chronic pain originates in a specific tissue or group of tissues, it may be advantageous to target pain control in the periphery and thereby circumvent the known risks associated with non-specific systemic treatments. This review spotlights a number of promising targets for peripheral pain control including the transient receptor potential (TRP) family of neuronal ion channels, the family of proteinase activated receptors (PARs), cannabinoids, and opioids. A critical appraisal of these targets in preclinical models of disease is given and their suitability as future peripheral analgesics is discussed.  相似文献   
182.
Placebo analgesic effects appear to be related to patients' perception of the therapeutic intervention. In this paper, we review quantitative findings of how the relationship with the physician and the verbal suggestions given for relief may influence patients' perception of a treatment and how patients' expectations and emotional feelings may affect treatment outcome. We also present qualitative data from interviews with patients who have experienced pain relief following a placebo or an active treatment. A special focus is given to the temporal development of placebo analgesia at psychological and neurophysiological levels. Finally, we discuss the extent to which the quantitative and qualitative findings supplement or contrast with each other, and we touch upon possible implications of patients' direct experience as central for placebo analgesia.  相似文献   
183.
184.
The field of placebo research has made considerable progress in the last years and it has become a major focus of interest. We know now that the placebo effect is a real neurobiological phenomenon and that the brain's 'inner pharmacy' is a critical determinant for the occurrence of psychobiological and behavioural changes relevant to healing processes and well-being. However, harnessing the advantages of placebo effects in healthcare is still a challenge. The first part of the theme issue summarizes and discusses the various kinds of placebo mechanisms across medical fields, thereby not only focusing on two main explanatory models-expectation and conditioning theory-but also taking into account empathy and social learning, emotion and motivation, spirituality and the healing ritual. The second part of the issue focuses on questions related to transferring knowledge from placebo research into clinical practice and discusses implications for the design and interpretation of clinical trials, for the therapeutic settings in daily patient care, and for future translational placebo research.  相似文献   
185.
Methods for the visualization of RNAs are urgently needed for studying a wide variety of cellular processes. Here we report on-bead screening of RNA libraries and its application to the isolation of specific fluorescence-enhancing RNA sequences. A one-bead-one-compound combinatorial RNA library with over one million different sequences was synthesized using the split-and-mix method. Solid-phase synthesis of 30 mer RNAs was performed on 15 ??m and 60 ??m diameter polystyrene beads bearing a non-cleavable linker. The RNA-derivatized beads were incubated with the well-established FlAsH pre-fluorophore and then screened for fluorescence enhancement, either by manually picking the brightest beads under a fluorescence microscope or by sorting with a FACS instrument. A protocol was established for sequence determination from single beads. While numerous RNA sequences showed increased fluorescence when immobilized, only few of them influenced the fluorescence properties of the FlAsH dye when detached from the beads. One of these sequences was found to induce a bathochromic shift in the excitation (from 492 to 510 nm) and emission (from 512 to 523 nm) maxima. This shift was accompanied by a 3.6-fold fluorescence enhancement of FlAsH fluorescence intensity. Mutation studies on the sequence revealed a rather robust structural motif.  相似文献   
186.
目的研究留置针联合镇痛泵在外科病人术后的镇痛护理。方法采用留置针联合镇痛泵在外科病人术后给药的镇痛方法。结果留置针联合镇痛泵在外科病人术后的优点:操作简单、容易掌握、危险小、并发症少,大大减少经济支出,可保留7天。结论留置针联合镇痛泵在外科病人术后的镇痛取得较好效果。  相似文献   
187.
目的:探讨重组干扰质粒pshRNA-COX-2对人肝癌细胞Hep3B裸鼠皮下移植瘤生长和肿瘤血管生成的抑制作用。方法:重组干扰质粒pshRNA-COX-2转染Hep3B细胞并筛选后,RT-PCR和Western blot检测COX-2mRNA和蛋白表达,RT-PCR检测VEGFmRNA表达。将被成功转染的Hep3B细胞种植于裸鼠皮下,测量肿瘤大小,4周后处死裸鼠,免疫组织化学法检测肿瘤组织中COX-2蛋白表达和肿瘤微血管密度(MVD)。结果:与未转染细胞相比,干扰组COX-2mRNA和蛋白表达抑制率分别为65.3%和52.8%(P<0.05),干扰组VEGFmRNA表达抑制率为56.5%(P<0.05)。干扰组瘤体大小明显小于阴性组和空白组(P<0.01)。干扰组COX-2得分和MVD均明显低于阴性组和空白组(P<0.01)。结论:pshRNA-COX-2通过抑制COX-2表达明显抑制人肝癌细胞Hep3B裸鼠皮下移植瘤生长和肿瘤血管生成。  相似文献   
188.
摘要 目的:探讨经皮穴位电刺激联合常规镇痛对无痛人流术后宫缩痛镇痛效果及机制。方法:选择来我院行无痛人流患者100例。根据随机数字表法分为两组。对照组行术后常规镇痛治疗,同时在内关、合谷、三阴交最酸胀处黏贴电极但是不进行穴位刺激。观察组在术后常规镇痛基础上行经皮穴位电刺激治疗。对比不同时间点两组患者的机体一般情况、不同时间点两组患者的宫缩痛疼痛情况、T3时正性负性情绪量表评分、T3时血清P物质、前列腺素、5-羟色胺、β-内啡肽、强啡肽水平、T4点时的心理状态评分及满意度评分。结果:对照组T1、T2点时的BP、HR、RR、SpO2明显较同组T0点低,对照组T3点与观察组T1、T2、T3点时BP、HR、RR、SpO2与同组T0点对比无统计学意义(P>0.05);对照组T1、T2点时的BP、HR、RR、SpO2明显较观察组同时间点低(P<0.05)。T0点,两组VAS评分对比无统计学意义(P>0.05);T1、T2、T3点时间,观察组的VAS评分明显较对照组低(P<0.05);对照组T1、T2点的VAS评分明显较同组T0点高,观察组T1、T2、T3点的VAS评分明显较T0点低(P<0.05)。观察组的正性情绪明显较对照组高,负性情绪明显较对照组低(P<0.05)。观察组的血清P物质、前列腺素、5-羟色胺、β-内啡肽、强啡肽水平明显较对照组低(P<0.05)。观察组的心理状态评分明显较对照组低,满意度评分明显较对照组高(P<0.05)。结论:经皮穴位电刺激联合常规镇痛可明显改善无痛人流术后宫缩痛镇痛效果、患者心理状态及满意度,可能与其可降低血清P物质、前列腺素、5-羟色胺、β-内啡肽、强啡肽水平有关。  相似文献   
189.
摘要 目的:探讨在胸腔镜肺大疱切除术中应用肋间神经阻滞复合全麻联合静脉自控镇痛的术后镇痛效果及患者恢复情况。方法:研究对象选取进行胸腔镜肺大疱切除术的80例患者,依据简单数字表法分为对照组和观察组,每组各40例。对照组接受全麻联合静脉自控镇痛,观察组在此基础上复合肋间神经阻滞,比较两组术后镇痛效果及恢复情况。结果:与术前比,术后12 h、24 h两组患者的CD4+、CD4+/CD8+均先降低后升高,且观察组各时间点均高于对照组;两组患者的CD8+均先升高后降低,且观察组各时间点均低于对照组(P<0.05)。术后24 h、48 h,观察组比对照组在镇痛泵按压次数和输注镇痛药物总量有减少(P<0.05)。与对照组比,观察组患者的术毕到拔管时间、下床活动时间、住院时间均更短(P<0.05)。与对照组(22.50%、20.00%)比,观察组患者的并发症、不良反应总发生率(2.50%、5.00%)更低(P<0.05)。结论:在胸腔镜肺大疱切除术中应用肋间神经阻滞复合全麻联合静脉自控镇痛,取得了显著的镇痛成效,不仅能够减轻患者的术后疼痛,还能减轻机体免疫抑制,同时不增加并发症和不良反应发生风险,临床应用安全性较高。  相似文献   
190.
目的:探讨地佐辛用于神经外科患者术后镇痛的效果和安全性。方法:将64例ASAⅠ~Ⅱ级行神经外科手术患者随机分为两组,术后均以静脉自控镇痛(PCIA),其中A组(34例)用地佐辛,B组(30例)用舒芬太尼,观察两组镇痛、镇静效果及不良反应。结果:术后4 h、8 h、12 h、24 h视觉模拟评分(VAS)和不良反应发生率A组明显低于B组(P〈0.05),Ramsay评分明显高于B组(P〈0.05)。结论:地佐辛用于神经外科患者术后镇痛确切,不良反应少。  相似文献   
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