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21.
目的:探讨经皮穴位电刺激(TEAS)对老年髋关节置换术患者脑氧代谢以及术后认知功能、镇痛效果的影响。方法:选取2016年1月~2018年7月期间我院收治的行髋关节置换术患者91例为研究对象,将研究对象根据随机数字表法分为对照组(n=45)和研究组(n=46),对照组给予常规麻醉处理,研究组在对照组基础上给予TEAS,比较两组脑氧代谢、术后认知功能以及镇痛效果,记录两组术后的不良反应发生情况。结果:在降压开始后20 min(T1)、降压开始后40 min(T2)、停止降压后20 min(T3)时间点时,两组静脉血氧含量(Cjv O2)较降压前即刻(T0)时间点升高,且研究组高于对照组(P0.05),两组脑动-静脉血氧含量差(Da-jvO2)、脑氧摄取率(CERO2)较T0时间点降低,且研究组低于对照组(P0.05)。两组患者术后72h简易智能量表(MMSE)评分均较术前24h降低,但研究组高于对照组(P0.05),研究组术后认知功能障碍(POCD)发生率低于对照组(P0.05)。与术前比较,两组患者术后8h、术后24h、术后48h视觉疼痛模拟量表(VAS)评分均升高(P0.05),但研究组术后8h、术后24h、术后48h等时间点VAS评分均低于对照组(P0.05)。两组患者不良反应总发生率比较无差异(P0.05)。结论:TEAS对老年髋关节置换术后患者的镇痛效果确切,可有效改善脑氧代谢情况,提高术后认知功能,临床应用价值较高。  相似文献   
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目的:探讨右美托咪定对腹腔镜下子宫恶性肿瘤手术患者炎症因子以及认知功能的影响,为右美托咪定在腹腔镜下子宫恶性肿瘤手术的临床应用提供参考。方法:选择武汉科技大学附属普仁医院2015年7月至2017年6月收治的100例行腹腔镜下子宫恶性肿瘤手术患者作为研究对象,根据不同麻醉方式分为观察组和对照组两组,各50例,其中观察组患者在给予麻醉诱导前30 min,负荷剂量1.0μg/kg的右美托咪定静脉输注10 min,之后给予患者0.5μg/kg的右美托咪定持续性静脉输注至手术结束前30 min为止,对照组患者按照上述给药方法静脉输注同等容量的生理盐水。然后分别于麻醉诱导前(T0)、手术结束时(T1)、手术结束后4 h(T2)以及手术结束后1天(T3)取患者的外周静脉血,测定比较两组患者各相应时间点的血清C反应蛋白(CRP)、肿瘤坏死因子(TNF-α)、白细胞介素(IL-6)等炎症因子水平,外周血皮质醇(cor)、肾上腺素(E)、去甲肾上腺素(NE)等应激水平,MMSE评分、TMT完成时间等认知功能;并分析两组患者术后的不良反应发生情况。结果:两组患者T0时间的血清IL-6、TNF-α、CRP、cor、E、NE水平以及TMT、MMSE认知功能评分差异不具有统计学意义(P0.05),具有可比性;而观察组患者T1、T2、T3各相应时间点的血清IL-6、TNF-α、CRP、cor、E以及NE水平明显低于对照组(P0.05);观察组患者T2、T3各相应时间点的MMSE评分明显高于对照组,TMT评分值明显低于对照组(P0.05);且术后观察组患者的不良反应发生率明显低于对照组(P0.05)。结论:右美托咪定可以明显降低腹腔镜下子宫恶性肿瘤手术患者血清应激反应以及炎症因子水平,改善术后认知功能,减少术后不良反应的发生,效果显著,值得临床推广使用。  相似文献   
23.
From fine‐scale foraging to broad‐scale migration, animal movement is shaped by the distribution of resources. There is mounting evidence, however, that learning and memory also guide movement. Although migratory mammals commonly track resource waves, how resource tracking and memory guide long‐distance migration has not been reconciled. We examined these hypotheses using movement data from four populations of migratory mule deer (n = 91). Spatial memory had an extraordinary influence on migration, affecting movement 2–28 times more strongly than tracking spring green‐up or autumn snow depth. Importantly, with only an ability to track resources, simulated deer were unable to recreate empirical migratory routes. In contrast, simulated deer with memory of empirical routes used those routes and obtained higher foraging benefits. For migratory terrestrial mammals, spatial memory provides knowledge of where seasonal ranges and migratory routes exist, whereas resource tracking determines when to beneficially move within those areas.  相似文献   
24.
The dipeptidyl peptidase 4 inhibitor vildagliptin (VLD), a widely used anti‐diabetic drug, exerts favourable effects on vascular endothelium in diabetes. We determined for the first time the improving effects of VLD on mitochondrial dysfunction in diabetic mice and human umbilical vein endothelial cells (HUVECs) cultured under hyperglycaemic conditions, and further explored the mechanism behind the anti‐diabetic activity. Mitochondrial ROS (mtROS) production was detected by fluorescent microscope and flow cytometry. Mitochondrial DNA damage and ATP synthesis were analysed by real time PCR and ATPlite assay, respectively. Mitochondrial network stained with MitoTracker Red to identify mitochondrial fragmentation was visualized under confocal microscopy. The expression levels of dynamin‐related proteins (Drp1 and Fis1) were determined by immunoblotting. We found that VLD significantly reduced mtROS production and mitochondrial DNA damage, but enhanced ATP synthesis in endothelium under diabetic conditions. Moreover, VLD reduced the expression of Drp1 and Fis1, blocked Drp1 translocation into mitochondria, and blunted mitochondrial fragmentation induced by hyperglycaemia. As a result, mitochondrial dysfunction was alleviated and mitochondrial morphology was restored by VLD. Additionally, VLD promoted the phosphorylation of AMPK and its target acetyl‐CoA carboxylase in the setting of high glucose, and AMPK activation led to a decreased expression and activation of Drp1. In conclusion, VLD improves endothelial mitochondrial dysfunction in diabetes, possibly through inhibiting Drp1‐mediated mitochondrial fission in an AMPK‐dependent manner.  相似文献   
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Advanced glycation end-products (AGEs) trigger multiple metabolic disorders in the vessel wall that may in turn lead to endothelial dysfunction. The molecular mechanisms by which AGEs generate these effects are not completely understood. Oxidative stress plays a key role in the development of deleterious effects that occur in endothelium during diabetes. Our main objectives were to further understand how AGEs contribute to reactive oxygen species (ROS) overproduction in endothelial cells and to evaluate the protective effect of an antioxidant plant extract. The human endothelial cell line EA.hy926 was treated with native or modified bovine serum albumin (respectively BSA and BSA-AGEs). To monitor free radicals formation, we used H2DCF-DA, dihydroethidium (DHE), DAF-FM-DA and MitoSOX Red dyes. To investigate potential sources of ROS, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase and mitochondrial inhibitors were used. The regulation of different types of ROS by the polyphenol-rich extract from the medicinal plant Doratoxylon apetalum was also studied for a therapeutic perspective. BSA-AGEs exhibited not only less antioxidant properties than BSA, but also pro-oxidant effects. The degree of albumin glycoxidation directly influenced oxidative stress through a possible communication between NADPH oxidase and mitochondria. D. apetalum significantly decreased intracellular hydrogen peroxide and superoxide anions mainly detected by H2DCF-DA and DHE respectively. Our results suggest that BSA-AGEs promote a marked oxidative stress mediated at least by NADPH oxidase and mitochondria. D. apetalum plant extract appeared to be an effective antioxidant compound to protect endothelial cells.  相似文献   
28.
The vascular endothelium is an important regulator of vascular reactivity and preserves the balance between vasoconstrictor and vasodilator tone during normal physiologic conditions. Example endothelial-derived vasoconstrictors include endothelin-1 and thromboxane A2; example vasodilators include nitric oxide and prostacyclin. A growing body of evidence points to the existence of a non-nitric oxide, non-prostacyclin endothelium-derived vasodilatory factor of currently unclear identity, often referred to as endothelium-derived hyperpolarizing factor (EDHF). Recent research testifies to the significance of EDHF in endothelium-dependent vascular smooth muscle relaxation. Special emphasis has been placed on the role of small conductance calcium-activated potassium channels (SK) in facilitating the endothelial and vascular responses to EDHF across the microcirculation, including coronary, mesenteric, and pulmonary vascular beds. Meanwhile, decreased activity of endothelial SK channel activity has been implicated in the pathology of a variety of disease states that alter the balance between vasodilator and vasoconstrictor tone. Hence the primary goal of this review is to characterize the physiology of endothelial SK channels in the microvasculature under normal and pathological conditions. Themes of regulation and dysregulation of SK channel activity through the action of protein kinases, reactive oxygen species, and byproducts of intermediary metabolism provide unifying principles to tie together vascular pathology in altered metabolic states ranging from hypertension to diabetes, to ischemia-reperfusion. A comprehensive understanding of SK channel pathophysiology may provide a foundation for development of new therapeutics targeting SK channels, particularly SK channel potentiators, that may have widespread application for many chronic disease states.  相似文献   
29.
Background and objectivesThe ageing population and the increasing dependency associated with it, makes the caregiver a highly relevant figure nowadays. The present study analyzes the socio-demographic differences between family and professional caregivers and their satisfaction and implication in a training program for caregivers.MethodsThe sample consisted of 59 caregivers of older people (37 were family caregivers and 22 professional caregivers) which received and implemented a caregivers training program in their daily care functions. These caregivers were trained in communication skills and cognitive stimulation strategies so they could use them in their daily care activities with the older adults under their care during a period of 3 months. All the participants were assessed with a socio-demographic questionnaire, 2 questionnaires to analyze their satisfaction with their work and the training received and one questionnaire to analyze their ability to detect and react to memory and behavior problems in the older adults they attended.ResultsThe results showed socio-demographic differences, improvements in satisfaction in family caregivers and a greater commitment in their daily work after the treatment in both groups although these effects could be due to different reasons.ConclusionsThe research shows the benefits of carrying out training programs for caregivers as they significantly increase the quality and satisfaction with caregiving. The study also displays the need to adjust such programs taking into account that the socio-demographic characteristics and training needs are different depending on whether de caregiver is a family member or a professional.  相似文献   
30.
IntroductionRecent evidence of a causal link between Phosphodiesterase-5-inhibitor (PDE-5i) use and melanoma has caused concern in PDE-5i use and was even addressed in the 2018 American Urological Association guideline on erectile dysfunction (ED). Given that several studies have affirmed this low probability but statistically significant association, one might expect a shift in melanoma diagnoses since PDE-5is were introduced in 1998. We sought to determine if the introduction of PDE-5i drugs for ED treatment increased incidence of melanoma.MethodsThe Surveillance, Epidemiology, and End Results (SEER) database was used to compare the incidence of melanoma diagnosis in American men between 1973 and 2015, providing over a decade of data before and after PDE-5i introduction in 1998. Interrupted time-series and logistic regression were used to assess this relationship.ResultsOver 43 years, the SEER database has reported 292,166 cases of Melanoma, with males accounting for 53.7% of cases (Standard deviation [SD] 3%, Range 47.5–58.3%). After the introduction of PDE-5i, there was no proportional increase in melanoma diagnoses, in fact demonstrating a 2% lower incidence from prediction models (p < 0.05).ConclusionOur analysis of the SEER database demonstrates that the trend in incidence of melanoma has fallen in the era of PDE-5i use for ED. These findings may be of value in counseling patients anxious about the potential association between PDE-5i use and skin cancer; however, continued research analyzing individual-level risk are needed.  相似文献   
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