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1.
《Anaesthesia and Intensive Care Medicine》2020,21(11):572-577
Phaeochromocytomas and paragangliomas (PPGL) are catecholamine-secreting neuroendocrine tumours. These tumours may be identified incidentally, as part of a work-up for multiple endocrine neoplasia or following haemodynamic surges during unrelated procedures. Advances in preoperative management and improved management of intraoperative haemodynamic instability have significantly reduced surgical mortality from around 40% to less than 3%. Surgery is the definitive treatment in most cases and laparoscopic resection where possible is associated with improved outcomes. Anaesthetic management of PPGL cases represents a unique haemodynamic challenge both before, during and after tumour resection. In this article we describe the physiology of these tumours, their diagnosis, preoperative optimization methods, intraoperative anaesthetic management and management of postoperative complications. 相似文献
2.
Unconditional Positivity-Preserving and Energy Stable Schemes for a Reduced Poisson-Nernst-Planck System
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Hailiang Liu & Wumaier Maimaitiyiming 《Communications In Computational Physics》2020,27(5):1505-1529
The Poisson-Nernst-Planck (PNP) system is a widely accepted model for
simulation of ionic channels. In this paper, we design, analyze, and numerically validate a second order unconditional positivity-preserving scheme for solving a reduced
PNP system, which can well approximate the three dimensional ion channel problem.
Positivity of numerical solutions is proven to hold true independent of the size of time
steps and the choice of the Poisson solver. The scheme is easy to implement without
resorting to any iteration method. Several numerical examples further confirm the
positivity-preserving property, and demonstrate the accuracy, efficiency, and robustness of the proposed scheme, as well as the fast approach to steady states. 相似文献
3.
目的:探讨改良大骨瓣联合软通道微创介入逐渐减压术治疗重型颅脑损伤的疗效。方法方便选择自2009年12月—2014年11月该院收治的重型颅脑损伤病例70例,随机分为改良组和对照组2组,每组35例,改良组施行改良大骨瓣联合软通道微创介入逐渐减压术,对照组按标准大骨瓣开颅、硬脑膜一次性全切开,对比分析两组的并发症发生率及预后。结果改良组发生迟发性颅内血肿、大面积脑梗塞及弥漫性脑肿胀等并发症9例(25.7%,9/35),预后良好者23例(65.7%,23/35),对照组发生并发症19例(54.3%,19/35),预后良好者14例(40.0%,14/35),两组并发症发生率和预后差异具有统计学意义(P<0.05)。结论改良大骨瓣联合软通道微创介入逐渐减压术治疗重型颅脑损伤,效果良好,显著降低死亡率。 相似文献
4.
目的 探究预防性静滴钾离子、镁离子对急性心梗后并发室性心律失常的预防作用。方法 选择2015年1月-2018年1月于西宁市第一人民医院进行治疗的78例急性心肌梗死患者为研究对象,按照随机数字表法将其均分为观察组与对照组,每组各39例患者。对照组患者进行常规急性心梗治疗,观察组患者在对照组基础上加用门冬氨酸钾镁进行治疗,对比两组治疗有效率,对比两组治疗前后血液流变学指标纤维蛋白原(Fib)、凝血酶原时间(PT)、血小板计数(Plt),对比两组治疗期间不良反应发生率及心律失常发生率。结果 治疗后,观察组患者治疗有效率为87.18%,对照组为76.92%,两组对比差异具有统计学意义(P<0.05)。治疗前两组患者Fib、PT以及Plt水平对比差异不具有统计学意义;治疗后,两组患者Plt及Fib水平低于治疗前,PT水平高于治疗前,差异有统计学意义(P<0.05);治疗后观察组患者Plt及Fib水平低于对照组,PT水平高于对照组(P<0.05)。观察组患者不良反应发生率稍高于对照组,但对比差异不具有统计学意义。观察组心律失常发生率为7.69%,对照组为15.38%,两组对比差异具有统计学意义(P<0.05)。结论 预防性静滴钾离子与镁离子能够显著降低急性心梗患者心律失常发生率,同时有利于提高治疗有效率,改善其血流变指标,且安全性较高。 相似文献
5.
Michael M Gezalian Luigi Mangiacotti Padmesh Rajput Nicklaus Sparrow Konrad Schlick Shouri Lahiri 《Journal of cerebral blood flow and metabolism》2021,41(4):693
Adrenoceptor and calcium channel modulating medications are widely used in clinical practice for acute neurological and systemic conditions. It is generally assumed that the cerebrovascular effects of these drugs mirror that of their systemic effects – and this is reflected in how these medications are currently used in clinical practice. However, recent research suggests that there are distinct cerebrovascular-specific effects of these medications that are related to the unique characteristics of the cerebrovascular anatomy including the regional heterogeneity in density and distribution of adrenoceptor subtypes and calcium channels along the cerebrovasculature. In this review, we critically evaluate existing basic science and clinical research to discuss known and putative interactions between adrenoceptor and calcium channel modulating pharmacotherapies, the neurovascular unit, and cerebrovascular anatomy. In doing so, we provide a rationale for selecting vasoactive medications based on lesion location and lay a foundation for future investigations that will define neuroprotective paradigms of adrenoceptor and calcium channel modulating therapies to improve neurological outcomes in acute neurological and systemic disorders. 相似文献
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8.
《Drug metabolism and pharmacokinetics》2019,34(5):308-316
LC-MS quantification of drug metabolites is sometimes impeded by the availability of internal standards that often requires customized synthesis and/or extensive purification. Although isotopically labeled internal standards are considered ideal for LC-MS/MS based quantification, de novo synthesis using costly isotope-enriched starting materials makes it impractical for early stage of drug discovery. Therefore, quick access to these isotope-enriched compounds without chemical derivatization and purification will greatly facilitate LC-MS/MS based quantification. Herein, we report a novel 18O-labeling technique using metabolizing enzyme carboxylesterase (CES) and its potential application in metabolites quantification study. Substrates of CES typically undergo a two-step oxygen exchange with H218O in the presence of the enzyme, generating singly- and doubly-18O-labeled carboxylic acids; however, unexpected hydrolytic behavior was observed for three of the test compounds – indomethacin, piperacillin and clopidogrel. These unusual observations led to the discovery of several novel hydrolytic mechanisms. Finally, when used as internal standard for LC-MS/MS based quantification, these in situ labeled compounds generated accurate quantitation comparable to the conventional standard curve method. The preliminary results suggest that this method has potential to eliminate laborious chemical synthesis of isotope-labeled internal standards for carboxylic acid-containing compounds, and can be developed to facilitate quantitative analysis in early-stage drug discovery. 相似文献
9.
目的建立了一种高效液相色谱-三重四极杆串联质谱法,对氯沙坦钾原料药中遗传毒性杂质N-亚硝基-N-甲基-4-氨基丁酸(NMBA)进行测定。方法色谱柱为岛津Shim-pack XR-ODSⅡ色谱柱(2.0 mm×150 mm,2.2μm),流动相为0.1%甲酸水溶液(A)和甲醇(B),进行梯度洗脱,流速0.3 mL·min^-1,柱温为40℃,采用ESI离子化-三重四极杆质谱多反应监测(MRM)正离子模式检测,碰撞电压分别为-11,-13和-13 V,碰撞气氩气270 kPa,NMBA的离子对分别为m/z 147.15→117.10,147.15→87.10和147.15→44.10。结果该方法中NMBA在1~100 ng·mL^-1内线性关系良好,日内和日间的保留时间和峰面积的重复性良好(RSD均小于1.10%,n=6和n=18),低、中、高3个浓度的平均回收率在94.40%~98.04%之间。结论本方法简单方便,可快速有效的对氯沙坦钾原料药中NMBA进行限度检查并实现定量分析。 相似文献
10.
Bi-Hua BIE Yong CHEN Zhi-Qi ZHAO Institute of Neurobiology Fu-Dan University Shanghai China Institute of Shanghai Physiology Chinese Academy of Sciences Shanghai China 《中国神经科学杂志》2006,(2)
Objective Ligustrazine, also named as tetramethylpyrazine, is a compound purified from Ligusticum chuanxiong hort and has ever been testified to be a calcium antagonist. The present investigation was to determine the antinoci-ceptive effect of ligustrazine and, if any, the peripheral ionic mechanism involved. Methods Paw withdrawal Latency ( PWL) to noxious heating was measured in vivo and whole-cell patch recording was performed on small dorsal root ganglion (DRG) neurons. Results Intraplantar injection of ligustrazine (0.5 mg in 25μl) significantly prolonged the withdrawal latency of ipsilateral hindpaw to noxious heating in the rat. Ligustrazine not only reversibly inhibited high-voltage gated calcium current of dorsal root ganglion (DRG) neuron in dose-dependent manner with IC50 of 1.89 mmol/L, but also decreased tetrodotoxin (TTX) -resistant sodium current in relatively selective and dose-dependent manner with IC50 of 2.49 mmol/L. Conclusion The results suggested that ligustrazine could elevate the threshold of thermal nociception through inhibiting the high-voltage gated calcium current and TTX-resistant sodium current of DRG neuron in the rat. 相似文献