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991.
Ionic liquid modified silicas with high adsorption capacity for phenols prompt us to deeply explore the contribution of interactions between the adsorbent and adsorbate, with a particular focus on hydrophobicity, π–π, electrostatic and acid–base interactions. Herein, by introducing a series of typical substituent groups including N,N-dimethylaminopropyl (A), benzyl (B), dodecyl (D) and naphthylmethyl (N) in an imidazole ring (Im), three mono-immobilized and two co-immobilized imidazolium ionic liquid modified silicas, namely SilprAImCl, SilprBImCl, SilprNImCl, SilprDBImCl and SilprDAImCl, werre synthesized for removal and recovery of 2,4-dinitrophenol (2,4-DNP) from aqueous solutions. Adsorption kinetics, isotherms, thermodynamic analysis and desorption experiments have been carried out. The experimental results reveal that the substituent groups such as N,N-dimethylaminopropyl, benzyl and naphthylmethyl on the imidazole ring can significantly enhance the adsorption of 2,4-DNP via the acid–base interaction or π–π interaction and the adsorption capacity of 2,4-DNP follows the order: SilprNImCl > SilprAImCl > SilprBImCl. Furthermore, SilprDBImCl exhibits the largest adsorption capacity and SilprDAImCl has the lowest among the five adsorbents. These interesting finds indicate that the combination of hydrophobicity and π–π interactions lead to enhanced adsorption performance towards 2,4-DNP, while the combination of the hydrophobicity and acid–base interactions can restrain greatly adsorption of 2,4-DNP from aqueous medium. Adsorption mechanisms of 2,4-DNP on the five adsorbents have been clarified. These results will provide a deeper insight for efficient removal of phenols from water environments.Ionic liquid modified silicas with high adsorption capacity for phenols prompt us to deeply explore the contribution of interactions between the adsorbent and adsorbate, with a particular focus on hydrophobicity, π–π, electrostatic and acid–base interactions. 相似文献
992.
目的探讨自然周期IVF结合未成熟卵母细胞IVM(自然周期IVF/IVM)和IVM技术与控制性促排卵技术(COH)相比,在不孕症治疗中的临床价值。方法根据筛查标准,将患者治疗方案分为以下3种类型:(A)自然周期IVF/IVM;(B)IVM;(C)COH。结果在1686个移植周期中,31.3%的周期(528个)应用自然周期IVF/IVM技术,12.8%实施IVM技术,55.9%通过COH方案治疗。自然周期IVF/IVM、IVM和COH的临床妊娠率分别为33.9%、39.8%和31.1%,IVM组高于其他两组但各组之间无显著差异,胚胎着床率也无显著差异。而IVM组的流产率(36.0%)高于其他两组(31.3%和25.9%),无显著统计学差异。结论从本研究可以看出,自然周期IVF/IVM和IVM方案可以解决近一半周期的不孕症患者,并且可以获得与COH相近的临床妊娠率。 相似文献
993.
目的探究超高龄(≥80岁)原发性脑出血患者的临床特点和预后情况。方法回顾性分析本院2011年1月至2013年1月期间收治170例原发性脑出血患者临床资料(超高龄者45例,对照组125例),对比超高龄患者(≥80岁)和对照组(〈80岁)在临床症状、体征、影像学表现、疾病治疗等的差异,比较分析两组患者的生存情况。结果超高龄组中,女性所占的比例高于对照组,既往有高血压病史者、起病时有明确诱因或处于活动状态、入院时收缩压、舒张压低于对照组(P〈0.05)。超高龄组脑叶出血的情况多于对照组(31.1%比12.0%,P〈0.05),基底节出血的情况则少于对照组(37.8%比62.4%,P〈0.05);超高龄组采用手术治疗低于对照组,在住院时间上长于对照组,中位累积生存时间低于对照组(P〈0.05)。结论超高龄原发性脑出血可能是一种特殊类别的脑出血,脑血管淀粉样变性极有可能是其发病的重要病因。 相似文献
994.
995.
Regenerative responses after mild heart injuries for cardiomyocyte proliferation in zebrafish
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Junji Itou Ryutaro Akiyama Steve Pehoski Xiaodan Yu Hiroko Kawakami Yasuhiko Kawakami 《Developmental dynamics》2014,243(11):1477-1486
Background: The zebrafish heart regenerates after various severe injuries. Common processes of heart regeneration are cardiomyocyte proliferation, activation of epicardial tissue, and neovascularization. In order to further characterize heart regeneration processes, we introduced milder injuries and compared responses to those induced by ventricular apex resection, a widely used injury method. We used scratching of the ventricular surface and puncturing of the ventricle with a fine tungsten needle as injury‐inducing techniques. Results: Scratching the ventricular surface induced subtle cardiomyocyte proliferation and responses of the epicardium. Endothelial cell accumulation was limited to the surface of the heart. Ventricular puncture induced cardiomyocyte proliferation, endocardial and epicardial activation, and neo‐vascularization, similar to the resection method. However, the degree of the responses was milder, correlating with milder injury. Sham operation induced epicardial aldh1a2 expression but not tbx18 and WT1. Conclusions: Puncturing the ventricle induces responses equivalent to resection at milder degrees in a shorter time frame and can be used as a simple injury model. Scratching the ventricle did not induce heart regeneration and can be used for studying wound responses to epicardium. Developmental Dynamics 243:1477–1486, 2014. © 2014 Wiley Periodicals, Inc. 相似文献
996.
STK11 Domain XI Mutations: Candidate Genetic Drivers Leading to the Development of Dysplastic Polyps in Peutz–Jeghers Syndrome
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Zhiqing Wang Baoping Wu Rebecca A. Mosig Yulan Chen Fei Ye Yali Zhang Wei Gong Lanbo Gong Fei Huang Xinying Wang Biao Nie Haoxuan Zheng Miao Cui Yadong Wang Juan Wang Chudi Chen Alexandros D. Polydorides David Y. Zhang John A. Martignetti Bo Jiang 《Human mutation》2014,35(7):851-858
Peutz–Jeghers syndrome (PJS) is a rare hereditary disorder resulting from mutations in serine/threonine kinase 11 (STK11) and characterized by gastrointestinal (GI) hamartomatous polyps, mucocutaneous pigmentation, and an increased risk for specific cancers. Little is known about the genetic implications of specific STK11 mutations with regard to their role in dysplastic and malignant transformation of GI polyps. Peripheral blood genomic DNA samples from 116 Chinese PJS patients from 52 unrelated families were investigated for STK11 mutations. Genotype–phenotype correlations were investigated. The mutation detection rate was 67.3% (51.9% point mutations, 15.4% large deletions). Fourteen out of the 25 point mutations identified were novel. Nearly one‐third of all mutations, 8/27 (29.6%), were in exon 7, the shortest out of the nine exons. Strikingly, mutations affecting protein kinase domain XI, encoded in part by exon 7, correlated with a 90% (9/10) incidence of GI polyp dysplasia. In contrast, only two out of 17 (11.8%) nondomain XI mutations were linked to polyp dysplasia (P = 0.0001). The extent of the association between dysplasia and the development of GI‐related cancers is currently unknown but our results highlight a novel STK11 genotype–phenotype association as the basis for future genetic counseling and basic research studies. 相似文献
997.
Leibin Shen Jun Wang Yongdong Yi Chenmin Ye Rongrong Wang Guojun Xia Chengyang Yu Fuyang Tu Jingxuan Xu Zhiqiang Zheng 《Drug testing and analysis》2019,11(4):595-600
The aim of this study was to investigate the possible effect of orally administered isavuconazole, ketoconazole, or voriconazole on the pharmacokinetics of methadone in rats. Twenty Sprague–Dawley (SD) rats were divided randomly into four groups: Group A (control), group B (5 mg/kg isavuconazole), group C (5 mg/kg ketoconazole), and group D (5 mg/kg voriconazole). A single dose of methadone was administrated half an hour later. Methadone in plasma concentrations and its metabolite EDDP in microsomes were determined by ultra‐high‐performance liquid chromatography–tandem mass spectrometry method (UPLC–MS/MS), and pharmacokinetic parameters were calculated by DAS version 3.0. The Cmax of methadone in groups C and D increased to 2.7‐fold and 5‐fold, respectively. While AUC increased in three groups and group D increased the most. Also, isavuconazole, ketoconazole, and voriconazole showed inhibitory effect on human and rat microsomes. The inhibition ratios of isavuconazole, ketoconazole, and voriconazole in rat liver microsome were 97.87%, 96.74% and 78.9%, respectively (p < 0.01), while in human liver microsome, inhibition ratios were 86.97%, 96.46%, and 53.11%, respectively. And the IC50 for inhibition activity of isavuconazole, ketoconazole, and voriconazole in rat microsomes were 7.76 μM, 8.33 μM, and 4.45 μM, respectively. Our study indicated that taking methadone combine with ketoconazole, isavuconazole, or voriconazole could reduce the metabolism rate of methadone and prolong the pharmacological effects in vivo and in vitro. 相似文献
998.
目的 评价内镜下组织牵拉夹联合金属夹在闭合内镜黏膜下剥离术(endoscopic submucosal dissection,ESD)术后创面中的效果和安全性。
方法 收集2020年6月1日—2020年6月30日期间因消化道病变于江苏省人民医院消化科行ESD治疗并使用组织牵拉夹联合金属夹夹闭手术创面的患者的资料,观察患者缝合时间、术中和术后并发症及术后住院时间等指标。
结果 本研究共纳入6例患者,其中男1例、女5例,年龄(59.2±9.0)岁,胃病变4例,结肠病变2例。ESD术后创面直径(2.7±0.9)cm,缝合时间(8.8±1.8)min。患者均使用1枚组织牵拉夹,使用金属夹3~11枚,平均7枚;除1例升结肠病变患者出现术中穿孔,余无术中或术后出血;患者术后住院(4.2±1.5)d。
结论 内镜下组织牵拉夹联合金属夹能有效、安全地闭合ESD术后创面。 相似文献
999.
目的初步探讨外周血 Th17细胞亚群的比例以及 IL-17的表达水平在 RA 和 AS 患者接受 TNF-α拮抗剂治疗前后的改变及其意义。方法选择 RA 患者27例和 AS 患者22例,2种疾病中各有14例患者接受 TNF-α拮抗剂治疗40周。对照组24名来源于健康献血者。采用流式细胞术检测外周血 CD4+T 细胞中 Th17细胞亚群的比例,ELISA 检测外周血 IL-17表达水平。符合正态分布数据采用2个独立样本 t 检验,不符合正态分布则采用 Wilcoxon 秩和检验,患者治疗前后的比较采用配对 t 检验。结果治疗前,RA 和 AS 患者外周血 CD4+ T 细胞中 Th17细胞亚群的比例显著高于健康对照组[RA 1.03%(0.66%,1.78%)与健康对照0.50%(0.43%,0.67%),Z=-3.236,P<0.01;AS(1.16±0.09)%与健康对照(0.59±0.06)%,t=5.226,P<0.01]。同样,IL-17的表达水平在2组疾病中也显著升高[RA(32.3±2.5) pg/ml,健康对照(14.3±2.5) pg/ml,t=5.070,P<0.01;AS 28.98(23.84,36.14) pg/ml,健康对照11.84(5.33,22.12) pg/ml,Z=-4.103,P<0.01]。 TNF-α拮抗剂治疗后,2组疾病 CD4+T 细胞中 Th17细胞亚群比例无明显变化[RA 驻(0.1045±0.2126)%;AS 驻(0.0025±0.1838)%],但 IL-17表达水平则明显下降[RA 驻(-13.5±5.0) pg/ml;AS 驻(-16.0±1.9) pg/ml]。结论 Th17细胞及其分泌的细胞因子 IL-17在 RA 和 AS 的发病机制中起重要作用,TNF-α拮抗剂对 AS 和 RA 患者 Th17细胞亚群炎症细胞因子的分泌功能有明显的抑制作用,但40周的治疗仍不能降低 Th17细胞比例,这可能是 TNF-α拮抗剂短期治疗后疾病复发的原因之一。 相似文献
1000.
目的通过动态对比增强(dynamic contrast-enhanced,DCE)MRI定量评估血脑屏障(blood-brain barrier,BBB)的通透性,探讨急性缺血性脑卒中患者BBB通透性的变化及相关影响因素。方法将50例急性缺血性脑卒中患者根据不同治疗方案,分为常规药物组12例,静脉溶栓组19例和取栓组19例,患者在发病72 h内完成DCEMRI(基线时),8例患者发病14 d复查影像检查,发病3个月随访时行改良的Rankin量表(mRS)评分,将mRS评分0~2分为预后良好。使用T1DCE-MRI Extend模型计算BBB通透性指标容积转运常数(Ktrans)值,并计算脑梗死侧与脑梗死对侧Ktrans值的比值(Ki/c)。比较所有患者脑梗死侧与脑梗死对侧、发病14 d复查与基线时、3组Ktrans值和Ki/c值差异,用多因素线性回归分析lg(Ki/c)值的相关影响因素。结果所有患者脑梗死侧Ktrans值较脑梗死对侧明显增高[0.0047(0.0019,0.0087)/min vs 0.0011(0.0003,0.0016)/min,P=0.000];发病14 d复查Ki/c值较基线时明显增高[70.77(13.43,399.43)vs 5.31(3.58,12.64),P=0.012]。常规药物组lg(Ki/c)值为0.42±0.49,静脉溶栓组lg(Ki/c)值为0.77±0.32,取栓组lg(Ki/c)值为0.85±0.41,静脉溶栓组和取栓组lg(Ki/c)值较常规药物组明显升高(P=0.021,P=0.005),静脉溶栓组与取栓组lg(Ki/c)值比较,差异无统计学意义(P=0.534)。常规药物组、静脉溶栓组和取栓组发病3个月预后良好比例比较,差异无统计学意义(66.7%vs 52.6%vs 52.6%,P=0.695)。多因素线性回归分析显示,lg(Ki/c)值与治疗方案(P=0.017)和脑梗死病史(P=0.030)有关。结论急性缺血性脑卒中患者BBB通透性与不同治疗方法、既往脑梗死病史有关,并且发病14 d BBB通透性较72 h内明显增高。 相似文献