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101.
目的:建立液相色谱-串联质谱法(UPLC-MS/MS)同时测定人血浆中头孢哌酮与舒巴坦的浓度,分析头孢哌酮/舒巴坦血药浓度监测结果,为临床合理用药提供参考。方法:以氯唑沙宗为内标,采用Waters BEHC18柱(2.1 mm×100 mm,1.7 μm)进行分离,通过串联质谱仪,负离子检测模式下,以多反应监测(MRM)方式进行定量测定。对某院2018年以不同给药方案进行治疗的73例住院患者测定的头孢哌酮/舒巴坦血药浓度结果进行分析。结果:头孢哌酮与舒巴坦在测定条件下1~200 mg·L-1范围内线性关系良好,两者日内精密度RSD均<10%,基质效应分别为(72.77±0.99)%与(75.72±0.11)%,提取回收率均>90%。73例患者共监测血药浓度96次,其中不同给药方案2 g,q8 h(43例次);2 g,q12 h(26例次);2 g,q6 h(27例次),各组头孢哌酮血药浓度的中位数分别为34.12 mg·L-1(4.12~177.79 mg·L-1)、31.23 mg·L-1(1.89~251.8 mg·L-1)、59.96 mg·L-1(1.77~140.58 mg·L-1),舒巴坦血药浓度的中位数分别为6.3 mg·L-1(0.61~136.01 mg·L-1)、28.83 mg·L-1(0.5~133.69 mg·L-1)、11.17 mg·L-1(0.73~143.53 mg·L-1)。Mann-Whitney U检验显示,头孢哌酮血药浓度结果无统计学差异(P>0.05),舒巴坦有统计学差异(P<0.05)。结论:本检测方法操作简便、快速、重复性好,可满足临床头孢哌酮与舒巴坦浓度的检测;头孢哌酮/舒巴坦在不同给药方案下血药浓度结果与个体差异相关,有必要开展血药浓度监测并依据结果适时调整用药方案,提高治疗效果减少耐药率的发生。 相似文献
102.
《Drug metabolism and pharmacokinetics》2019,34(1):87-94
The purpose of this study was to elucidate the involvement of Mate1 in the tubular secretion of trimethoprim and saturation of Mate1-mediated efflux to address the mechanisms underlying the pharmacokinetic drug interactions with trimethoprim. Trimethoprim is a more potent inhibitor of MATE2-K than MATE1 with Ki values (μM) of 0.030–0.28 and 2.4–5.9, respectively. Trimethoprim is a substrate of human MATE1 and MATE2-K with Km values of 2.3 ± 0.9 and 0.018 ± 0.004 μM, and mouse Mate1, but not human OCT2, mouse Oct1 and Oct2. Pyrimethamine significantly reduced the renal clearance (CLR) of trimethoprim (mL/min/kg) from 40.0 ± 5.1 to 20.1 ± 3.7 (p < 0.05). Trimethoprim was given to mice at three infusion rates (150, 500, and 1500 nmol/min/kg). Together with an increase in the plasma concentrations of trimethoprim, the CLR (mL/min/kg) of trimethoprim decreased to 25.9 ± 3.2, 13.5 ± 5.7, and 8.92 ± 1.50 at the respective rates. Trimethoprim decreased the CLR of rhodamine 123 in an infusion rate-dependent manner: 11.5 ± 1.3 (control), 5.17 ± 1.55, 1.31 ± 0.50, and 0.532 ± 0.180. These results suggest that Mate1 mediates the tubular secretion of trimethoprim, and at therapeutic doses, MATEs-mediated efflux can be saturated, and thereby, cause drug interactions with other MATE substrates. 相似文献
103.
Joshua Manghelli Lisa Brown Hany B. Tadros Nabil A. Munfakh 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(5):491-494
The inflammatory response induced by cardiopulmonary bypass decreases vascular tone, which in turn can lead to vasoplegic syndrome. Indeed the hypotension consequent to on-pump cardiac surgery often necessitates vasopressor and intravenous fluid support. Methylene blue counteracts vasoplegic syndrome by inhibiting the formation of nitric oxide.We report the use of methylene blue in a 75-year-old man who developed vasoplegic syndrome after cardiac surgery. After the administration of methylene blue, his hypotension improved to the extent that he could be weaned from vasopressors. The use of methylene blue should be considered in patients who develop hypotension refractory to standard treatment after cardiac surgery. 相似文献
104.
《Brain stimulation》2020,13(5):1159-1167
BackgroundInhibitory control refers to a central cognitive capacity involved in the interruption and correction of actions. Dysfunctions in these cognitive control processes have been identified as major maintaining mechanisms in a range of mental disorders such as ADHD, binge eating disorder, obesity, and addiction. Improving inhibitory control by transcranial direct current stimulation (tDCS) could ameliorate symptoms in a broad range of mental disorders.ObjectiveThe primary aim of this pre-registered meta-analysis was to investigate whether inhibitory control can be improved by tDCS in healthy and clinical samples. Additionally, several moderator variables were investigated.MethodsA comprehensive literature search was performed on PubMed/MEDLINE database, Web of Science, and Scopus. To achieve a homogenous sample, only studies that assessed inhibitory control in the go-/no-go (GNG) or stop-signal task (SST) were included, yielding a total of 75 effect sizes from 45 studies.ResultsResults of the meta-analysis indicate a small but significant overall effect of tDCS on inhibitory control (g = 0.21) which was moderated by target and return electrode placement as well as by the task. The small effect size was further reduced after correction for publication bias.ConclusionBased on the studies included, our meta-analytic approach substantiates previously observed differences between brain regions, i.e., involvement of the right inferior frontal gyrus (rIFG) vs. the right dorsolateral prefrontal cortex (rDLPFC) in inhibitory control. Results indicate a small moderating effect of tDCS on inhibitory control in single-session studies and highlight the relevance of technical and behavioral parameters. 相似文献
105.
目的 探讨中性粒细胞与淋巴细胞比值(neutrophil to lymphocyte ratio,NLR)对三阴性乳腺癌的临床预后影响及与Ki - 67表达的关系。方法 回顾性分析2006年1月 - 2012年12月于我院乳腺外科住院治疗的134例三阴性乳腺癌患者。NLR最佳临床分界值采用ROC曲线确定,并依此分NLR<2.64组和NLR≥2.64组。临床独立预后因素采用单因素和多因素Cox回归模型分析。术后生存时间和生存曲线比较采用Kaplan - Meier和log - rank方法。Ki - 67的表达采用免疫组织化学方法检测。结果 NLR是三阴性乳腺癌的独立预后因素,最佳临界值为2.64。NLR<2.64组术后中位DFS为39.10月,中位OS为52.30月;NLR≥2.64组术后中位DFS为27.35月,中位OS为37.35月。2组术后DFS和OS比较,差异具有统计学意义(P<0.05)。NLR低组伴Ki - 67表达阴性的三阴性患者术后中位DFS和OS生存时间显著高于其他情况。结论 NLR是三阴性乳腺癌的关键影响预后因素,具有重复性强、非侵袭性、方便实用等特性,可用于预测三阴性乳腺癌临床预后。 相似文献
106.
目的研究丹蛭降糖胶囊对糖尿病肾病大鼠的肾脏病理改变和足细胞自噬水平的影响,初步探讨其相应的作用机制。方法选取GK大鼠40只,采用醋酸脱氧皮质酮-盐皮下注射联合高脂饲料喂养诱导糖尿病肾病模型。造模成功后随机分为模型组、丹蛭降糖胶囊低剂量组[0.54 g/(kg·d)]、高剂量组[1.08 g/(kg·d)]、缬沙坦组[10 mg/(kg·d)],每组10只。另选取10只同周龄正常Wistar大鼠作为正常组。模型组和正常组给予等容积生理盐水。连续灌胃10周后检测空腹血糖(FBG)、血肌酐(SCr)、尿素氮(BUN)和尿微量蛋白(U-mAlb)。Western Blot检测肾小球p-mTOR、p-S6K1、Beclin-1、LC3和Nephrin蛋白的表达,HE染色和PAS染色后于光镜下观察肾脏病理变化,电镜下观察各组亚细胞形态结构变化。结果与正常组比较,模型组FBG、SCr、BUN、U-mAlb水平升高(P<0.01);与模型组比较,丹蛭降糖胶囊低、高剂量组和缬沙坦组U-mAlb水平降低(P<0.01)。模型组可见肾小球基底膜增厚,系膜基质沉积,足细胞损伤,各用药组均有不同程度改善,丹蛭降糖胶囊高剂量组足细胞内有较多自噬体形成。与正常组比较,模型组p-mTOR、p-S6K1的表达增高,Nephrin、Beclin-1和LC3的表达水平降低(P<0.01);与模型组比较,各用药组p-mTOR、p-S6K1的表达下降,Nephrin、Beclin-1和LC3的表达增高(P<0.01)。丹蛭降糖胶囊高剂量组和缬沙坦组Beclin1、LC3Ⅱ/LC3Ⅰ水平较丹蛭降糖胶囊低剂量组升高(P<0.05)。结论丹蛭降糖胶囊具有减轻糖尿病肾病大鼠U-mAIb、足细胞损伤及相关肾脏病理改变的作用,其机制可能与抑制mTOR/S6K1信号通路进而提高足细胞的自噬活性有关。 相似文献
107.
108.
目的探讨负载 IL-4 和 BMP-2 的氧化石墨烯(graphene oxide,GO)-羧甲基壳聚糖(carboxymethyl chitosan,CMC)凝胶诱导巨噬细胞 M2 型分化及对 BMSCs 成骨分化的影响。方法取 CMC、GO 制备混合溶液后,分别添加 PBS、IL-4、BMP-2 或 IL-4+BMP-2,在交联剂作用下制备单纯或负载不同因子的 GO-CMC 凝胶支架;取单纯 GO-CMC 凝胶表征观测,包括大体、扫描电镜及傅里叶变换红外吸收光谱仪(Fourier transform infrared spectroscopy,FTIR)检测,以单纯 CMC 凝胶作为对照;取负载不同因子的 GO-CMC 凝胶行体外缓释实验。取 4~5 周龄 SPF 级 SD 雌性大鼠分离培养巨噬细胞,分别与单纯以及负载不同因子的 GO-CMC 凝胶培养,24 h 后行 CD206 免疫荧光检测巨噬细胞分化情况;取第 3 代大鼠 BMSCs 分别与单纯以及负载不同因子的 GO-CMC 凝胶成骨诱导培养,10 d 后行 ALP 染色观测早期成骨,21 d 行茜素红染色观测晚期成骨。结果大体观察 GO-CMC 凝胶呈棕色、半透明状;扫描电镜观察示,GO-CMC 凝胶孔径及孔壁厚度与单纯 CMC 凝胶相似,但内壁粗糙度增加;FTIR 检测显示 CMC 发生聚合形成凝胶。体外缓释实验示 3 种负载不同因子的 GO-CMC 凝胶缓释性能相似,均呈线性缓慢释放因子。CD206 免疫荧光检测示 GO-CMC 凝胶可诱导巨噬细胞 M2 型分化,ALP 及茜素红染色示 GO-CMC 凝胶可诱导 BMSCs 成骨分化;其中负载 IL-4+BMP-2 的 GO-CMC 凝胶作用最显著(P<0.05)。 结论负载 IL-4 和 BMP-2 的 GO-CMC 凝胶可诱导巨噬细胞 M2 型分化,增强 BMSCs 成骨分化能力,为后期骨缺损修复及骨免疫调节研究提供了新的策略。 相似文献
109.
David Simon Koray Tascilar Sara Unbehend Sara Bayat Andreas Berlin Anna-Maria Liphardt Timo Meinderink Juergen Rech Axel J Hueber Georg Schett Arnd Kleyer 《Journal of bone and mineral research》2020,35(9):1695-1702
The impact of primary hand osteoarthritis (HOA) on bone mass, microstructure, and biomechanics in the affected skeletal regions is largely unknown. HOA patients and healthy controls (HCs) underwent high-resolution peripheral quantitative computed tomography (HR-pQCT). We measured total, trabecular, and cortical volumetric bone mineral densities (vBMDs), microstructural attributes, and performed micro–finite element analysis for bone strength. Failure load and scaled multivariate outcome matrices from distal radius and second metacarpal (MCP2) head measurements were analyzed using multiple linear regression adjusting for age, sex, and functional status and reported as adjusted Z-score differences for total and direct effects. A total of 105 subjects were included (76 HC: 46 women, 30 men; 29 HOA: 23 women, six men). After adjustment, HOA was associated with significant changes in the multivariate outcome matrix from the MCP2 head (p < .001) (explained by an increase in cortical vBMD (Δz = 1.07, p = .02) and reduction in the trabecular vBMD (Δz = −0.07, p = .09). Distal radius analysis did not show an overall effect of HOA; however, there was a gender-study group interaction (p = .044) explained by reduced trabecular vBMD in males (Δz = −1.23, p = .02). HOA was associated with lower failure load (−514 N; 95%CI, −1018 to −9; p = 0.05) apparent in males after adjustment for functional status. HOA is associated with reduced trabecular and increased cortical vBMD in the MCP2 head and a reduction in radial trabecular vBMD and bone strength in males. Further investigations of gender-specific changes of bone architecture in HOA are warranted. © 2020 The Authors. Journal of Bone and Mineral Research published by American Society for Bone and Mineral Research. 相似文献
110.
《中国现代医生》2020,58(14):5-8
目的研究经导管动脉化疗栓塞(TACE)对原发性肝癌患者的疗效及中性粒细胞/淋巴细胞计数比(NLR)、血小板/淋巴细胞计数比(PLR)的影响。方法选择2015年6月~2019年1月我院接诊的原发性肝癌患者80例作为研究对象,采用随机数表法将患者分为两组,每组各40例。对照组予传统肝切除术治疗,观察组采用TACE治疗。对比两组治疗后的临床效果,NLR、PLR、癌胚抗原(CEA)、可溶性B7-H4、可溶性白细胞介素-2受体(sIL-2R)及并发症发生情况。结果治疗后,两组患者的总有效率分别为75.00%和52.50%,观察组高于对照组,差异有统计学意义(P0.05);治疗前,两组患者NLR、PLR水平对比,差异无统计学意义(P0.05);治疗后,患者NLR、PLR水平下降,观察组低于对照组,差异有统计学意义(P0.05);治疗前,两组患者CEA、B7-H4、sIL-2R水平对比,差异无统计学意义(P0.05);治疗后,两组患者CEA、B7-H4、sIL-2R水平下降,观察组低于对照组,差异有统计学意义(P0.05);两组患者并发症发生率分别为17.50%、40.00%,观察组低于对照组,差异有统计学意义(P0.05)。结论在原发性肝癌患者中使用TACE效果显著,可有效改善患者肿瘤标志物水平,减少并发症,值得推广应用。 相似文献