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21.
One of the fundamental interests in neuroscience is to understand the integration of excitatory and inhibitory inputs along the very complex structure of the dendritic tree, which eventually leads to neuronal output of action potentials at the axon. The influence of diverse spatial and temporal parameters of specific synaptic input on neuronal output is currently under investigation, e.g. the distance-dependent attenuation of dendritic inputs, the location-dependent interaction of spatially segregated inputs, the influence of GABAergig inhibition on excitatory integration, linear and non-linear integration modes, and many more.With fast micro-iontophoresis of glutamate and GABA it is possible to precisely investigate the spatial and temporal integration of glutamatergic excitation and GABAergic inhibition. Critical technical requirements are either a triggered fluorescent lamp, light-emitting diode (LED), or a two-photon scanning microscope to visualize dendritic branches without introducing significant photo-damage of the tissue. Furthermore, it is very important to have a micro-iontophoresis amplifier that allows for fast capacitance compensation of high resistance pipettes. Another crucial point is that no transmitter is involuntarily released by the pipette during the experiment.Once established, this technique will give reliable and reproducible signals with a high neurotransmitter and location specificity. Compared to glutamate and GABA uncaging, fast iontophoresis allows using both transmitters at the same time but at very distant locations without limitation to the field of view. There are also advantages compared to focal electrical stimulation of axons: with micro-iontophoresis the location of the input site is definitely known and it is sure that only the neurotransmitter of interest is released. However it has to be considered that with micro-iontophoresis only the postsynapse is activated and presynaptic aspects of neurotransmitter release are not resolved. In this article we demonstrate how to set up micro-iontophoresis in brain slice experiments.  相似文献   
22.
Microwave-assisted synthetic techniques were used to quickly and reproducibly produce silica nanoparticle sols using an acid catalyst with nanoparticle diameters ranging from 30-250 nm by varying the reaction conditions. Through the selection of a microwave compatible solvent, silicic acid precursor, catalyst, and microwave irradiation time, these microwave-assisted methods were capable of overcoming the previously reported shortcomings associated with synthesis of silica nanoparticles using microwave reactors. The siloxane precursor was hydrolyzed using the acid catalyst, HCl. Acetone, a low-tan δ solvent, mediates the condensation reactions and has minimal interaction with the electromagnetic field. Condensation reactions begin when the silicic acid precursor couples with the microwave radiation, leading to silica nanoparticle sol formation. The silica nanoparticles were characterized by dynamic light scattering data and scanning electron microscopy, which show the materials'' morphology and size to be dependent on the reaction conditions. Microwave-assisted reactions produce silica nanoparticles with roughened textured surfaces that are atypical for silica sols produced by Stöber''s methods, which have smooth surfaces.  相似文献   
23.
An RNA-Seq strategy was used to obtain the complete set of protein-coding mitochondrial genes from two rodent taxa. Thanks to the next generation sequencing (NGS) 454 approach, we determined the complete mitochondrial DNA genome from Graphiurus kelleni (Mammalia: Rodentia: Gliridae) and partial mitogenome from Pedetes capensis (Pedetidae), and compared them with published rodent and outgroup mitogenomes. We finished the mitogenome sequencing by a series of amplicons using conserved PCR primers to fill the gaps corresponding to tRNA, rRNA and control regions. Phylogenetic analyses of the mitogenomes suggest a well-supported rodent phylogeny in agreement with nuclear gene trees. Pedetes groups with Anomalurus into the clade Anomaluromorpha, while Graphiurus branches within the squirrel-related clade. Moreover, Pedetes + Anomalurus branch with Castor into the mouse-related clade. Our study demonstrates the utility of NGS for obtaining new mitochondrial genomes as well as the importance of choosing adequate models of sequence evolution to infer the phylogeny of rodents.  相似文献   
24.
目的:探讨右美托咪定对老年恶性肿瘤全麻手术患者术后细胞免疫功能、认知功能及炎症因子水平的影响。方法:选取2017年2月~2019年6月期间到我院择期行手术治疗的老年恶性肿瘤患者119例,根据随机数字表法将患者分为对照组(n=59)和研究组(n=60),研究组麻醉中输注右美托咪定,对照组麻醉中输注同容量等速率的生理盐水,比较两组患者围术期指标、细胞免疫功能、不良反应、炎症因子指标、简易智力状态量表(MMSE)评分。结果:两组患者术后第3 d的CD4~+/CD8~+、CD3~+、CD4~+较术前下降,CD8~+较术前升高(P0.05);研究组术后第3 d的CD4~+/CD8~+、CD3~+、CD4~+高于对照组,CD8~+则低于对照组(P0.05)。两组术后第3 d的血清高迁移率族蛋白1(HMGBl)、白介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平均升高,但研究组低于对照组(P0.05)。两组手术时间、术中出血量、麻醉时间比较无差异(P0.05)。两组患者术前、术后第1 d、术后第3 d的MMSE评分呈先下降后升高趋势(P0.05),且研究组术后第1 d、第3 d的MMSE评分高于对照组(P0.05)。两组不良反应发生率比较无统计学差异(P0.05)。结论:老年恶性肿瘤全麻手术患者术中输注右美托咪定,可减轻细胞免疫抑制及炎症反应,对术后早期的认知功能下降有一定预防作用。  相似文献   
25.
Esophageal carcinoma, with a increasing incidence, is one of the most aggressive carcinomas in gastrointestinal tract. Epidemiologic studies demonstrate an association of oral pathogens with multiple diseases, including rheumatoid arthritis, cardiovascular diseases, diabetes, and gastrointestinal malignancies. Nevertheless, a causal relationship between oral pathogens and esophageal squamous cell carcinoma (ESCC) has not been elucidated. Here, we found that Porphyromonas was significantly enriched in the saliva of patients with ESCC, compared with that in normal human. In vitro studies showed that Porphyromonas gingivalis (P. gingivalis) promoted the proliferation and motility of ESCC cells, as evidenced by up regulated expression of key molecules implicated in NF-κB signaling pathway. These findings, for the first time, demonstrated a role of oral pathogens in inducing ESCC tumorigenesis and metastasis, which might involve regulation of NF-κB signaling pathway.  相似文献   
26.
A growing literature identifies associations between subjective and biometric indicators of wellbeing. These associations, together with the ability of subjective wellbeing metrics to predict health and behavioral outcomes, have spawned increasing interest in wellbeing as an important concept in its own right. However, some social scientists continue to question the usefulness of wellbeing metrics. We contribute to this literature in three ways. First, we introduce a biometric measure of wellbeing – pulse – that hs been little used. Using nationally representative data on 165,000 individuals from the Health Survey for England and Scottish Health Surveys we show that its correlates are similar in a number of ways to those for happiness, and that it is highly correlated with wellbeing metrics, as well as self-assessed health. Second, we examine the determinants of pulse rates in mid-life (age 42) among the 9000 members of the National Child Development Study, a birth cohort born in a single week in 1958 in Britain. Third, we track the impact of pulse measured in mid-life (age 42) on health and labor market outcomes at age 50 in 2008 and age 55 in 2013. The probability of working at age 55 is negatively impacted by pulse rate a decade earlier. The pulse rate has an impact over and above chronic pain measured at age 42. General health at 55 is lower the higher the pulse rate at age 42, while those with higher pulse rates at 42 also express lower life satisfaction and more pessimism about the future at age 50. Taken together, these results suggest social scientists can learn a great deal by adding pulse rates to the metrics they use when evaluating people’s wellbeing.  相似文献   
27.
摘要 目的:观察全身麻醉下不同脑电双频指数(BIS)对老年胃肠道恶性肿瘤患者应激反应、炎性因子和术后认知功能的影响。方法:选择2020年10月-2021年4月在新疆医科大学附属肿瘤医院初诊的住院老年胃肠道恶性肿瘤患者,共98例。据随机数字表法分为浅麻醉组(n=49,BIS值45~55)和深麻醉组(n=49,BIS值30~40)。对比两组苏醒质量、应激反应、炎性因子、术后认知功能、血流动力学及不良反应。结果:浅麻醉组的苏醒时间、定向力恢复时间、气管拔管时间短于深麻醉组(P<0.05)。插管后即刻(T1)~术毕(T5)时间点,两组心率(HR)、平均动脉压(MAP)均下降后升高(P<0.05)。深麻醉组T1~T5时间点HR、MAP高于浅麻醉组(P<0.05)。手术开始2 h(T4)、拔管后60 min(T6)时间点,两组皮质醇(Cor)、促肾上腺皮质激素(ACTH)水平呈升高趋势,且浅麻醉组高于深麻醉组(P<0.05)。T4、T6时间点,两组白介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平持续升高,但浅麻醉组低于深麻醉组(P<0.05)。深麻醉组的术后3 d、术后7 d 简明精神状态量表(MMSE)评分低于浅麻醉组(P<0.05)。两组不良反应发生率组间对比无差异(P>0.05)。结论:全身麻醉下老年胃肠道恶性肿瘤患者BIS值范围30~40可维持更平稳的血流动力学,应激反应低,但是其对认知功能影响相对较大;BIS值在45~55之间时,患者苏醒快,炎性因子水平更低;临床应结合实际情况合理调控BIS值。  相似文献   
28.
摘要 目的:研究全身麻醉联合椎旁神经阻滞在胸腔镜下肺叶切除术患者的应用效果,探讨其对患者术后认知功能和炎 症反应的影响。方法:选取2017年-2021年在我院接受胸腔镜下肺叶切除术治疗的患者100例,根据其麻醉方式的不同分为对照组(50例)和研究组(50例),对照组给予全身麻醉,研究组给予全身麻醉联合椎旁神经阻滞。比较两组患者手术时间、麻醉时间、术中出血量、舒芬太尼和瑞芬太尼用量、术后疼痛情况、简易智力状态检查量表(MMSE)评分和血清C-反应蛋白(CRP)、白介素-6(IL-6)水平。结果:两组患者手术时间、麻醉时间和术中出血量比较无显著差异(P>0.05),而研究组患者舒芬太尼用量和瑞芬太尼用量均低于对照组(P<0.05);研究组患者术后6、12、24和48小时疼痛评分均较对照组患者低(P<0.05);两组患者术前MMSE评分无差异(P>0.05),研究组患者术后6、12、24和48小时MMSE评分均较对照组高(P<0.05);两组患者术前血清CRP和IL-6水平无显著差异,但研究组患者术后24小时血清CRP和IL-6水平均显著低于对照组(P<0.05)。结论:全身麻醉联合椎旁神经阻滞用于胸腔镜下肺叶切除术患者可有效减少手术中麻醉药物用量,术后镇痛效果更好,对患者认知功能损伤更低,并且术后炎症更低。  相似文献   
29.
摘要 目的:探讨术前超声引导下腰方肌阻滞(QLB)联合全身麻醉对肾移植患者术后血清应激反应和疼痛相关指标的影响。方法:选择我院2019年9月~2021年8月期间收治的行肾移植手术的患者82例作为观察对象。根据随机数字表法分为A组和B组,分别为41例。A组给予全身麻醉,B组给予术前超声引导下QLB联合全身麻醉,对比两组静息视觉疼痛模拟(VAS)评分、自控静脉镇痛中的舒芬太尼使用量、有效按压次数,对比两组术后血清应激反应和疼痛相关指标变化,对比两组不良反应发生情况。结果:B组术后6 h、12 h、24 h、48 h静息VAS评分低于A组(P<0.05)。B组自控静脉镇痛中的舒芬太尼使用量少于A组,有效按压次数少于A组(P<0.05)。B组拔管后、术后24 h血糖(Glu)、皮质醇(Cor)低于A组(P<0.05)。两组术后24 h P物质(SP)、前列腺素E2(PGE2)及5-羟色胺(5-HT)均升高,但B组低于A组(P<0.05)。两组的不良反应发生率对比无差异(P<0.05)。结论:术前超声引导下QLB联合全身麻醉用于肾移植手术患者,可有效减轻疼痛和应激反应,减少自控静脉镇痛中的舒芬太尼使用量、有效按压次数,且不增加不良反应发生率。  相似文献   
30.
摘要 目的:观察超声引导下髂筋膜神经阻滞联合全麻对老年股骨近端骨折患者术后血清疼痛介质前列腺素E2(PGE2)、P物质(SP)和认知功能及睡眠质量的影响。方法:选取2018年8月~2021年9月期间我院收治的择期行手术治疗的老年股骨近端骨折患者80例,根据随机数字表法分为对照组(40例,常规全麻方案)和观察组(40例,超声引导下髂筋膜神经阻滞联合全麻方案),对比两组麻醉效果、血流动力学、疼痛情况、认知功能和睡眠质量,观察不同模式麻醉下的安全性。结果:观察组的苏醒及拔管时间均短于对照组,丙泊酚使用量少于对照组(P<0.05)。两组置入喉罩时(T1)~术毕时(T3)心率(HR)先升高后下降,平均动脉压(MAP)先下降后升高(P<0.05);观察组T1~T3时点HR低于对照组,MAP高于对照组(P<0.05)。两组术后24 h血清PGE2、SP水平和视觉疼痛模拟量表(VAS)评分均升高,但观察组低于对照组(P<0.05)。两组术后1 d、2 d、3 d 蒙特利尔认知评估量表(MoCA)评分较术前先下降后升高(P<0.05);观察组术后2 d、3 d MoCA评分高于对照组(P<0.05)。两组术后1 d、2 d、3 d匹兹堡睡眠质量评估量表(PSQI)评分较术前先升高后下降(P<0.05);观察组术后1 d、2 d、3 d PSQI评分低于对照组(P<0.05)。两组不良反应发生率对比无差异(P>0.05)。结论:老年股骨近端骨折患者术中选用超声引导下髂筋膜神经阻滞联合全麻,镇痛效果显著,可稳定机体血流动力学,减少对认知功能和睡眠质量的影响,且安全性良好。  相似文献   
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