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101.
摘要 目的:探讨脑电双频指数(BIS)监测下右美托咪定联合七氟醚对颅内动脉瘤介入栓塞术患者苏醒质量、血清氧化应激指标和神经损伤标志物的影响。方法:采用随机数字表法,将我院2019年3月-2021年6月期间收治的80例颅内动脉瘤介入栓塞术患者分为研究组(BIS监测下右美托咪定联合七氟醚,n=40)和对照组(BIS监测下七氟醚,n=40),观察两组血流动力学、苏醒质量、血清氧化应激指标和神经损伤标志物水平变化。记录两组围术期间不良反应发生状况。结果:气管插管后1 min(T1)~拔管后10 min(T4)时点,两组平均动脉压(MAP)、心率(HR)升高后下降,但研究组低于对照组同时点(P<0.05)。与对照组比较,研究组苏醒时间、恢复呼吸时间、拔管时间较短(P<0.05)。T1~T4时点,两组超氧化物歧化酶(SOD)、过氧化氢酶(CAT)水平下降后升高,但研究组较对照组同时点高(P<0.05)。术后1 d,两组人脑髓鞘碱性蛋白(MBP)、神经元特异性烯醇化酶(NSE)、S100?茁水平升高,但研究组低于对照组同时点(P<0.05)。对照组、研究组的不良反应发生率组间对比无显著性差异(P>0.05)。结论:BIS监测下七氟醚联合右美托咪定应用于颅内动脉瘤介入栓塞术患者中,可提高苏醒质量,减轻氧化应激水平和神经损伤程度,稳定血流动力学波动。 相似文献
102.
摘要 目的:探讨自体输血与异体输血对创伤性颅脑损伤(TBI)开颅手术患者凝血功能、细胞免疫功能和神经损伤标志物的影响。方法:回顾性分析2019年4月~2022年5月期间在本院行开颅手术的120例TBI患者的临床资料。根据输血方式的不同将患者分为异体输血组(n=58,异体输血)和自体输血组(n=62,自体输血),观察两组临床指标、细胞免疫功能、凝血功能、神经损伤标志物和不良反应发生率情况。结果:两组患者手术出血量、输血量、输注含凝血成分血制品比例对比,差异无统计学意义(P>0.05)。自体输血组出院时CD3+、CD4+、CD4+/CD8+高于异体输血组,CD8+低于异体输血组(P<0.05)。两组出院时凝血酶原时间(PT)、凝血酶时间(TT)、纤维蛋白原(FIB)、活化部分凝血活酶时间(APTT)组间对比无统计学差异(P>0.05)。自体输血组出院时S100钙结合蛋白B(S100B)、神经胶质原纤维酸性蛋白(GFAP)、神经元特异性烯醇化酶(NSE)低于异体输血组(P<0.05)。两组不良反应发生率组间比较无差异(P>0.05)。结论:自体输血用于TBI开颅手术患者,对患者的凝血功能影响较小,同时还可改善机体细胞免疫功能,降低神经损伤标志物水平。 相似文献
103.
《遗传学报》2023,50(2):63-76
The phenomenon of planar cell polarity is critically required for a myriad of morphogenetic processes in metazoan and is accurately controlled by several conserved modules. Six “core” proteins, including Frizzled, Flamingo (Celsr), Van Gogh (Vangl), Dishevelled, Prickle, and Diego (Ankrd6), are major components of the Wnt/planar cell polarity pathway. The Fat/Dchs protocadherins and the Scrib polarity complex also function to instruct cellular polarization. In vertebrates, all these pathways are essential for tissue and organ morphogenesis, such as neural tube closure, left–right symmetry breaking, heart and gut morphogenesis, lung and kidney branching, stereociliary bundle orientation, and proximal–distal limb elongation. Mutations in planar polarity genes are closely linked to various congenital diseases. Striking advances have been made in deciphering their contribution to the establishment of spatially oriented pattern in developing organs and the maintenance of tissue homeostasis. The challenge remains to clarify the complex interplay of different polarity pathways in organogenesis and the link of cell polarity to cell fate specification. Interdisciplinary approaches are also important to understand the roles of mechanical forces in coupling cellular polarization and differentiation. This review outlines current advances on planar polarity regulators in asymmetric organ formation, with the aim to identify questions that deserve further investigation. 相似文献
104.
L. Romo-Parada L.-P. Vézina P. M. Charest F. Castaigne C. Willemot 《Physiologia plantarum》1991,83(4):664-674
Differences in mitochondrial membrane composition and ultrastructure were studied after storage of cauliflower ( Brassica oleracea , L., Botrytis group) for 5 days at 25°C in air or under controlled atmospheres: 3% O2 , 21% O2 + 15% CO2 or 3% O2 + 15% CO2 . In air, postharvest senescence involved a 20% decrease in mitochondrial phospholipid content. A large reduction in the relative abundance of phosphati-dylcholine (PC) and in the degree of unsaturation of PC and phosphatidyl ethanolamine (PE) was observed. However, the degree of unsaturation increased in cardiolipin (CL). Storage under 3% O2 did not prevent phospholipid breakdown. Low O2 prevented the relative decrease in PC observed during storage in air and the loss of linoleic acid from PC, but not from PE. This relative protection offered by the low O2 atmosphere was lost under 3% O2 + 15% CO2 . The high CO2 atmospheres caused twice as much loss in phospholipids as that observed during storage in air. Extensive loss of mitochondrial protein, a marked decrease in phospholipid to protein ratio, and electron micrograph observations suggest structural alterations in the presence of high CO2 . 相似文献
105.
Ectopic ion channels developed locally at the injury site after nerve damage by light ligation around common sciatic nerve of the rats. Different channel types have different processes of formation, accumulation and degeneration. During the first three days after injury, mechanically activated channels that are modulated by Ca++ channel activities first appeared. As the nerve fibers begin to be excited by TEA, a blocker of K+ channels, suggesting that the accumulation of K+ channels, the responsibility of mechanically activated channels was declining. Onset of K+ channels was from the 3rd postoperative day and lasted up to the fiftieth day. This time course of K+ channel development was closely related to allodynia and hyperalgesia of neuropathic animal behaviour. The results suggest that chronic contraction injury induces a dynamic change in the ectopic mechanically activated channels and K+ channels at the injury site of nerve and there is an interchange in the development time courses of the mechanic 相似文献
106.
Crystal structures of the Ser/Thr phosphatase calcineurin (protein phosphatase 2B) have recently been solved by X-ray crystallography, both in the free-protein state, and complexed with the immunophilin/immunosuppressant FKBP12/FK506. Core elements of the calcineurin phosphatase have been found to be similar to the corresponding elements of Ser/Thr phosphatase 1 and purple acid phosphatase. The structures provide a basis for understanding calcineurin inhibition by a ternary complex of immunophilin and immunosuppressant proteins. 相似文献
107.
为了解决高氧预适应(HyperoxicpreconditioningHOP)对大鼠心肌缺血再灌注时自由基的影响,本实验将实验组大鼠放入高压氧舱内,每日吸80-85%氧气(1atm)6h,连续7d。利用Langendorf装置做成心肌缺血再灌注模型,采用电子自旋共振技术测定自由基含量。实验动物随机分为二组,第一组为对照组:缺血10min,再灌注60min。第二组为HOP组:缺血10min,再灌注60min。实验观察冠脉回流液中自由基PBN加合物含量。结果表明:在再灌注过程中,1、5、10min3个时间点,HOP组PBN加合物含量较对照组明显减少。提示:HOP能减少缺血再灌注时自由基的产生。 相似文献
108.
本实验采用D-氨基半乳糖(D-GalN)诱导的大鼠急性肝损伤模型,观察大鼠肝脏组织化学的变化,探讨肝炎平对急性肝损伤的保护作用。实验分为四组,即正常对照组、模型组、肝炎平及肝得健保护组。结果表明:肝炎平对肝细胞膜系统有一定的保护作用。肝炎平组和肝得健组SDH、CCO及ChE活性明显高于模型组,且与正常对照组相近。本实验模型组ACP的活性明显高于正常组,而肝炎平组ACP的活性明显低于模型组,与正常对照组无显著性差异。提示:肝炎平可显著改善因D-氨基半乳糖所致肝损害的作用。且其对肝细胞的保护作用与肝得健一致。 相似文献
109.
D. J. Morré R. Merriman L. R. Tanzer L. -Y. Wu D. M. Morré W. C. MacKellar 《Protoplasma》1995,184(1-4):203-208
Summary Inhibition of NADH oxidase activity of plasma membranes isolated from a series of human xenografts and cell lines by the antitumor sulfonylurea, N-(4-methylphenylsulfonyl)-N-(4-chlorophenyl) urea (LY 181984), correlated with the ability of the sulfonylurea to inhibit cell growth. Growth of rat kidney cells either untransformed or transformed with Kirsten-ras (K-ras) were unaffected by the sulfonylurea. Similarly, the NADH oxidase activity of isolated plasma membranes from K-ras transformed cells was unaffected by LY 181984. In contrast, when transformed with Harvey-ras (H-ras), both growth and NADH oxidase activity were inhibited. With the inactive but structurally related LY 181985 (N-4-methylphenyl-sulfonyl)-N-(phenyl)urea), neither growth nor plasma membrane NADH oxidase activity of either sulfonylurea-susceptible or -resistant tissues or cell lines was inhibited. Both sulfonylureas were inactive with rat liver plasma membranes but NADH oxidase activity of plasma membranes and growth with HeLa cells was inhibited by the active (LY 181984) but not by the inactive (LY 181985) sulfonylurea. The findings suggest a possible correlation between inhibition of plasma membrane NADH oxidase activity by the antitumor sulfonylureas and their oncolytic action. 相似文献
110.
The Second Messenger, Cyclic AMP, Is Not Sufficient for Myelin Gene Induction in the Peripheral Nervous System 总被引:1,自引:0,他引:1
Joseph F. Poduslo Randall S. Walikonis Marie-Christine Domec Carole T. Berg Carrie J. Holtz-Heppelmann 《Journal of neurochemistry》1995,65(1):149-159
Abstract: The adenylyl cyclase-cyclic AMP (cAMP) second messenger pathway has been proposed to regulate myelin gene expression; however, a clear correlation between endogenous cAMP levels and myelin-specific mRNA levels has never been demonstrated during the induction or maintenance of differentiation by the myelinating Schwann cell. Endogenous cAMP levels decreased to 8–10% of normal nerve by 3 days after crush or permanent transection injury of adult rat sciatic nerve. Whereas levels remained low after transection injury, cAMP levels reached only 27% of the normal values by 35 days after crush injury. Because P0 mRNA levels were 60% of normal levels by 14 days and 100% by 21 days after crush injury, cAMP increased only well after P0 gene induction. cAMP, therefore, does not appear to trigger myelin gene induction but may be involved in myelin assembly or maintenance. Forskolin, an activator of adenylyl cyclase, increased endoneurial cAMP levels only in the normal nerve, and in the crushed nerve beginning at 16 days after injury, but at no time in the transected nerve. Only by treating transected nerve with 3-isobutyl-1-methylxanthine (IBMX), an inhibitor of cAMP phosphodiesterases, in combination with forskolin was it possible to increase cAMP levels. No induction of myelin genes, however, was observed with short- or long-term treatment with IBMX and forskolin in the transected nerve. A three-fold increase in phosphodiesterase activity was observed at 35 days after both injuries, and a nonmyelinated nerve was shown to have even higher activity. These experiments, therefore, suggest an important role for phosphodiesterase in the inactivation of this second messenger-dependent stimuli when Schwann cells are non-myelinating, such as after sciatic nerve injury or in the nonmyelinated nerve, which again implies that cAMP may be required for the maintenance of the myelin sheath. 相似文献