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101.
目的:探讨右美托咪定复合罗哌卡因对膝关节置换术后的临床效果。方法:选取2015年2月~2018年12月期间在武警陕西省总队医院择期行膝关节置换术患者103例,根据随机数字表将患者分成对照组(n=51)和研究组(n=52),对照组股神经阻滞时给予罗哌卡因,研究组在对照组基础上联合右美托咪定。比较两组患者镇痛镇静效果、睡眠质量、应激反应以及不良反应。结果:研究组术后12 h、术后24 h、术后48 h视觉模拟评分(VAS)低于对照组(P0.05),Ramsay镇静评分则高于对照组(P0.05)。研究组术后24 h、术后48 h阿森斯失眠量表(AIS)评分均低于术前,且呈先降低后升高趋势(P0.05)。研究组术后24 h、术后48 h AIS评分低于对照组(P0.05)。两组患者手术开始即刻、术毕的去甲肾上腺素(NE)、肾上腺素(E)水平均上升,且呈先升高后降低趋势(P0.05);研究组手术开始即刻、术毕的NE、E水平低于对照组(P0.05)。两组不良反应发生率对比无统计学差异(P0.05)。结论:右美托咪定复合罗哌卡因方案应用于膝关节置换术,镇痛镇静效果确切,可减轻术中应激反应,有效改善睡眠质量,且不增加不良反应发生率,临床应用价值较高。  相似文献   
102.
目的:探讨单切口腹腔镜在结直肠手术中的应用效果及对炎症因子与应激反应的影响。方法:选择2018年1月至2019年10月我院接诊的98例结直肠癌患者,通过随机数表法分为2组,每组49例。观察组使用单切口腹腔镜结直肠癌根治术,对照组使用传统腹腔镜结直肠癌根治术,常规5孔操作法。比较两组围术期相关情况、手术前后血清炎症因子水平的变化、手术后应激反应及并发症的发生情况。结果:两组淋巴结清扫个数、中转开腹例数、术后排气时间比较差异均无统计学意义(P0.05),观察组手术时间明显长于对照组,脐切口长度、住院时间、术中出血量均显著短于或低于对照组;两组术后1 d、3 d、5 d时高敏C反应蛋白(hs-CRP)、肿瘤坏死因子-α(TNF-α)、白细胞介素-6(IL-6)、去甲肾上腺素(NE)、肾上腺素(E)、皮质醇(Cor)水平均明显高于术前(P0.05);且观察组术后1d、3d、5d时hs-CRP、TNF-α、IL-6、NE、E、Cor较对照组显著降低(P0.05);两组吻合口瘘、吻合口狭窄、吻合口出血、小肠穿孔、肠梗阻、感染的总发生率比较差异无统计学意义(P0.05)。结论:和传统5孔操作法相比,单切口腹腔镜结直肠癌根治术治疗结直肠癌患者的手术时间更长,但术后炎症因子表达更低,应激反应更小,有利于患者术后恢复。  相似文献   
103.
目的:探讨持续颅内压(ICP)监测对大面积脑梗死外科治疗预后的应用价值。方法:选取2013年3月至2018年3月期间在我院接受治疗的大面积脑梗死患者100例作为研究对象,所有患者经去骨瓣减压术后行ICP监测和生命体征监测,通过结果分为:低压组62例(2.70kPa≤ICP5.30kPa),高压组38例(ICP≥5.30 kPa)。记录患者ICP监测数值,接收者操作特征(ROC)曲线分析患者预后情况,对患者进行术后3个月内随访,了解患者平常活动能力进行判断预后的状况。观察ICP与预后的相关性。结果:两组患者性别、年龄、室速、室性早搏、糖尿病、高血压病、脑卒中、高脂血症、风心病、冠心病、扩张性心肌病、既往心肌梗死、肥厚性心肌病、甲亢性心脏病等资料比较差异无统计学意义(P0.05)。低压组患者中预后良好的ICP监测值显著低于预后不良者(P0.05),高压组中预后良好的ICP监测值显著低于预后不良者(P0.05)。ICP预测大面积脑梗死外科治疗预后的ROC曲线面积0.704,采用最大约等指数计算得出ICP预测大面积脑梗死外科治疗预后的最大AUC面积相应参数截止值为4.89,其中敏感度为0.435,特异性为0.896。结论:持续ICP监测结果显示ICP值越小,患者的预后就越好,ICP值越高,患者的预后越差。ICP监测对大面积脑梗死外科治疗的预后具有预测价值,对判断和改善预后能起到有效帮助,值得在临床推广应用。  相似文献   
104.
目的:分析程序性死亡因子-1(PD-1)、程序性死亡1-配体(PD-L1)的表达与肺癌临床病理特征及预后的相关性。方法:回顾性分析我院2015年3月~2016年6月收治的73例肺癌患者的临床资料,取距离切除肿瘤边缘3cm内的非癌组织作为癌旁组织。比较两组PD-1、PD-L1的表达,分析其和肺癌患者临床病理特征和预后的关系,采用COX比例回归分析肺癌患者预后的影响因素。结果:肺癌组织PD-1、PD-L1阳性表达率均显著高于癌旁组织(P0.05)。不同性别、年龄、病理类型、吸烟情况、EGFR表达、肿瘤大小肺癌患者PD-1、PD-L1的阳性表达率比较差异无统计学意义(P0.05);低分化程度、临床分期Ⅲ及Ⅳ期、有淋巴结转移肺癌患者PD-1、PD-L1阳性表达率分别高于中分化程度、临床分期Ⅲ期、无淋巴结转移患者,差异有统计学意义(P0.05)。PD-1、PD-L1阳性表达及阴性表达组无疾病进展生存期比较均有统计学差异(P0.05)。COX比例风险回归模型显示分化程度、临床分期、淋巴结转移、PD-1、PD-L1的表达是影响肺癌患者预后的危险因素(P0.05)。结论:肺癌组织PD-1、PD-L1呈高表达,可能参与肺癌的发生发展,有助于病情严重程度的评价和预后预测。  相似文献   
105.
Xia  Siyu  Wu  Ming  Chen  Si  Zhang  Tao  Ye  Lina  Liu  Jun  Li  Hui 《中国病毒学》2020,35(3):311-320
The mechanism of how SARS-CoV-2 causes severe multi-organ failure is largely unknown. Acute kidney injury(AKI) is one of the frequent organ damage in severe COVID-19 patients. Previous studies have shown that human renal tubule cells could be the potential host cells targeted by SARS-CoV-2. Traditional cancer cell lines or immortalized cell lines are genetically and phenotypically different from host cells. Animal models are widely used, but often fail to reflect a physiological and pathogenic status because of species tropisms. There is an unmet need for normal human epithelial cells for disease modeling. In this study, we successfully established long term cultures of normal human kidney proximal tubule epithelial cells(KPTECs) in 2 D and 3 D culture systems using conditional reprogramming(CR) and organoids techniques.These cells had the ability to differentiate and repair DNA damage, and showed no transforming property. Importantly, the CR KPTECs maintained lineage function with expression of specific transporters(SLC34 A3 and cubilin). They also expressed angiotensin-converting enzyme 2(ACE2), a receptor for SARS-CoV and SARS-CoV-2. In contrast, cancer cell line did not express endogenous SLC34 A3, cubilin and ACE2. Very interestingly, ACE2 expression was around twofold higher in 3 D organoids culture compared to that in 2 D CR culture condition. Pseudovirion assays demonstrated that SARS-CoV spike(S) protein was able to enter CR cells with luciferase reporter. This integrated 2 D CR and 3 D organoid cultures provide a physiological ex vivo model to study kidney functions, innate immune response of kidney cells to viruses, and a novel platform for drug discovery and safety evaluation.  相似文献   
106.
为了探讨Rh type C glycoprotein (RHCG)对非小细胞肺癌(non-small cell lung cancer,NSCLC)细胞增殖的影响及可能的作用机制,本研究使用荧光定量PCR法检测12对NSCLC及癌旁组织样本中RHCG mRNA的表达水平及pcDNA3.1-RHCG质粒对A549细胞RHCG m RNA的表达;采用CCK-8法检测细胞增殖能力;运用PI染色法检测细胞周期;使用免疫印迹法检p-PI3K、PI3K、p-AKT以及AKT蛋白表达水平。本研究发现,与癌旁组织比较,NSCLC中RHCG m RNA表达水平明显降低。RHCG过表达能抑制NSCLC细胞系A549细胞增殖能力。此外,RHCG过表达使A549细胞周期G1/S期转化发生阻滞。本研究还发现,RHCG过表达可下调A549细胞p-PI3K/PI3K和p-AKT/AKT水平。本研究表明,RHCG抑制NSCLC细胞增殖的作用与其抑制PI3K/AKT信号通路有关。  相似文献   
107.
Species concept and delimitation are fundamental to taxonomic and evolutionary studies. Both inadequate informative sites in the molecular data and limited taxon sampling have often led to poor phylogenetic resolution and incorrect species delineation. Recently, the whole chloroplast genome sequences from extensive herbarium specimen samples have been shown to be effective to amend the problem. Stachyuraceae are a small family consisting of only one genus Stachyurus of six to 16 species. However, species delimitation in Stachyurus has been highly controversial because of few and generally unstable morphological characters used for classification. In this study, we sampled 69 individuals of seven species (each with at least three individuals) covering the entire taxonomic diversity, geographic range, and morphological variation of Stachyurus from herbarium specimens for genome‐wide plastid gene sequencing to address species delineation in the genus. We obtained high‐quality DNAs from specimens using a recently developed DNA reconstruction technique. We first assembled four whole chloroplast genome sequences. Based on the chloroplast genome and one nuclear ribosomal DNA sequence of Stachyurus, we designed primers for multiplex polymerase chain reaction and high throughput sequencing of 44 plastid loci for species of Stachyurus. Data of these chloroplast DNA and nuclear ribosomal DNA internal transcribed spacer sequences were used for phylogenetic analyses. The phylogenetic results showed that the Japanese species Stachyurus praecox Siebold & Zucc. was sister to the rest in mainland China, which indicated a typical Sino‐Japanese distribution pattern. Based on diagnostic morphological characters, distinct distributional range, and monophyly of each clade, we redefined seven species for Stachyurus following an integrative species concept, and revised the taxonomy of the family based on previous reports and specimens, in particular the type specimens. Furthermore, our divergence time estimation results suggested that Stachyuraceae split from its sister group Crossosomataceae from the New World at ca. 54.29 Mya, but extant species of Stachyuraceae started their diversification only recently at ca. 6.85 Mya. Diversification time of Stachyurus in mainland China was estimated to be ca. 4.45 Mya. This research has provided an example of using the herbarium specimen‐based phylogenomic approach in resolving species boundaries in a taxonomically difficult genus.  相似文献   
108.
绵马贯众是中国传统常用中药,本研究以温度、时间、超声功率、液料比为影响因子,多糖得率为评价指标,通过响应面法优化超声辅助提取绵马贯众多糖的工艺条件,同时测定其基本理化性质及抗氧化活性。研究结果表明,绵马贯众多糖的最佳提取工艺条件为:温度64℃、时间60 min、超声功率210 W、液料比27 mL/g。此时多糖得率为9.57%,与预测值接近。理化性质分析表明绵马贯众多糖为含少量蛋白的酸性多糖。体外抗氧化研究表明绵马贯众多糖具有很强的DPPH自由基清除活性,IC50值为0.29 mg/mL;较好的羟基自由基清除活性,其IC50值为1.10 mg/mL;对DNA的氧化损伤有显著的保护作用。绵马贯众多糖可以作为一种潜在的抗氧化剂应用于食品和化妆品等领域。  相似文献   
109.
Understanding the interplay between bacterial fitness, antibiotic resistance, host immunity and host metabolism could guide treatment and improve immunity against antibiotic-resistant pathogens. The acquisition of levofloxacin (Lev) resistance affects the fitness of Vibrio alginolyticus in vitro and in vivo. Lev-resistant (Lev-R) V. alginolyticus exhibits slow growth, reduced pathogenicity and greater resistance to killing by the host, Danio rerio (zebrafish), than Lev-sensitive (Lev-S) V. alginolyticus, suggesting that Lev-R V. alginolyticus triggers a weaker innate immune response in D. rerio than Lev-S V. alginolyticus. Differences were detected in the metabolome of D. rerio infected with Lev-S or Lev-R V. alginolyticus. Maltose, a crucial metabolite, is significantly downregulated in D. rerio infected with Lev-R V. alginolyticus, and exogenous maltose enhances the immune response of D. rerio to Lev-R V. alginolyticus, leading to better clearance of the infection. Furthermore, we demonstrate that exogenous maltose stimulates the host production of lysozyme and its binding to Lev-R V. alginolyticus, which depends on bacterial membrane potential. We suggest that exogenous exposure to crucial metabolites could be an effective strategy for treating and/or managing infections with antibiotic-resistant bacteria.  相似文献   
110.
Phosphorus is a macronutrient that is essential for plant survival. Most land plants have evolved the ability to form a mutualistic symbiosis with arbuscular mycorrhizal (AM) fungi, which enhances phosphate (Pi) acquisition. Modulation of Pi transporter systems is the master strategy used by mycorrhizal plants to adapt to ambient Pi concentrations. However, the specific functions of PHOSPHATE TRANSPORTER 1 (PHT1) genes, which are Pi transporters that are responsive to high Pi availability, are largely unknown. Here, we report that AsPT5, an Astragalus sinicus (Chinese milk vetch) member of the PHT1 gene family, is conserved across dicotyledons and is constitutively expressed in a broad range of tissues independently of Pi supply, but is remarkably induced by indole-3-acetic acid (auxin) treatment under moderately high Pi conditions. Subcellular localization experiments indicated that AsPT5 localizes to the plasma membrane of plant cells. Using reverse genetics, we showed that AsPT5 not only mediates Pi transport and remodels root system architecture but is also essential for arbuscule formation in A. sinicus under moderately high Pi concentrations. Overall, our study provides insight into the function of AsPT5 in Pi transport, AM development and the cross-talk between Pi nutrition and auxin signalling in mycorrhizal plants.  相似文献   
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