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91.
92.
Xiurong Kang Qinghu Wang Suriguga Ao Moxiyele Wenlin Bao Chaoliang zhao a 《中草药(英文版)》2023,15(2):337-342
Objective: To establish a high-performance liquid chromatographic method (HPLC) for the simultaneous determination of sixteen compounds from Artemisia ordosica.
Methods: HPLC was used to analyze 16 quality indicators of A. ordosica. The HPLC conditions were as follows: Agilent Eclipse Plus C18 column (250 mm × 4.6 mm, 5 μm) with acetonitrile (A)-water (B) as mobile phase, gradient elution: 0?10 min, 75%?65% B; 10?30 min, 65%?35 % B; and finally 30?40 min, 35%?15% B. The flow rate was 1.0 mL/min, the column temperature was 40 °C, the injection volume was 10 μL, and monitored by absorbance at 285 nm for compounds 1?10, 12 and 225 nm for compounds 11, 13?16.
Results: Under the selected experimental chromatographic conditions, compounds 1?16 showed good linearity (r > 0.9993) in a wide concentration range. Their average recoveries were 99.50%, 95.38%, 97.75%, 96.00%, 98.20%, 97.50%, 95.50%, 99.33%, 96.75%, 96.50%, 98.50%, 97.83%, 99.20%, 95.33%, 97.33% and 96.30%, respectively, and the RSD were 1.99%, 1.81%, 1.63%, 1.98%, 1.67%, 1.92%, 1.74%, 1.67%, 1.90%, 1.72%, 1.88%, 1.83%, 1.79%, 1.76%, 1.81% and 1.96%, respectively.
Conclusion: Based on the results of the HPLC analysis, it was concluded that p-hydroxycinnamic acid (1), O-hydroxycinnamic acid (2), coniferyl alcohol (5), 5,4''-dihydroxy-7,3''-dimethoxyflavanone (8), 5,4''-dihydroxy-7-methoxyflavanone (9), 5-hydroxy-7,4''-dimethoxyflavanone (12), dehydrofalcarindiol (13), arteordoyn A (14), dehydrofalcarinol (15) and capillarin (16) are best suited for the role of quality indicators of A. ordosica grown in different ecological environments. 相似文献
93.
目的 研究卡氏乳香Boswellia carterii中的化学成分及其抗骨质疏松活性。方法 运用硅胶柱色谱、ODS柱色谱和制备高效液相色谱等方法进行化学成分分离,通过波谱数据及文献对比对其进行结构解析。结果 卡氏乳香的95%乙醇提取物中分离得到11个化合物,分别鉴定为 (1R,2E,8S,9R)-1,9-环氧-8-乙酰氧基-4,5-二氧代降西松烷型-2-烯(1)、rel(1S,3R,7E,11S,12R)-1,12-epoxy-4-methylenecembr-7-ene-3,11-diol(2)、boscartin F(3)、boscartene K(4)、fidmansumbin-13(17)-en-3,16-diene(5)、3α-acetoxyl-7-oxo-tirucalla-8,24-dien-21-oic acid(6)、boscartene N(7)、3β-hydroxy-tirucallic acid(8)、α-boswellic acid(9)、boscarterol O(10)、boscarterol F(11)。结论 化合物1是新化合物,命名为卡氏乳香素,化合物5为首次从乳香中分离得到,化合物2和10首次从该属植物中分离得到。对11个化合物进行抗骨质疏松活性筛选,发现化合物1、3、6和10具有良好的抑制破骨细胞活性。 相似文献
94.
探讨建立涵盖慢性乙型病毒性肝炎(CHB)诊断与鉴别诊断、治疗、药物选择及毒副作用预测、疗效监测、预后评估等全过程的疾病临床检验诊断路径的教学模式。根据CHB临床诊疗指南, 制订与疾病不同阶段相关的实验室检查检测策略, 建立CHB临床检验诊断路径, 以武汉大学第一临床学院2016级和2017级八年制本科生为研究对象, 通过随堂问卷比较其课堂教学效果。本研究首先建立了获得临床医生认可的CHB临床检验诊断路径, 其涵盖CHB疾病的诊断与鉴别诊断、治疗、药物选择及毒副作用预测、疗效监测、预后评估等全过程。该路径应用于2017级临床医学本科生课堂教学后, 教学质量评估指标均有较大程度的提升。此外, 随堂测验得分也有显著提高。综上, 基于CHB临床检验诊断路径的实验诊断学教学模式, 实现了实验诊断学与临床医学的融合, 提升了学生对CHB诊疗中各种实验室检查检测的整体认识, 教学质量得到了提高。 相似文献
95.
Qingpeng Song Bao Hai Wenkui Zhao Xin Huang Kaixi Liu Bin Zhu Xiaoguang Liu 《Orthopaedic Surgery》2021,13(2):659
To (i) introduce the technical notes of a novel full‐endoscopic foraminotomy with a large endoscopic trephine for the treatment of severe degenerative lumbar foraminal stenosis at L5S1 level; (ii) assess the primary clinical outcomes of this technique; (iii) compare the effectiveness of this full‐endoscopic foraminotomy technique and other previous techniques for lumbar foraminal stenosis. From January 2019 to August 2019, a retrospective study of L5S1 severe degenerative lumbar foraminal stenosis was performed in our center. All patients who were diagnosed with severe foraminal stenosis at L5S1 level and failed conservative treatment for at least 6 weeks were identified. Patients with segmental instability or other coexisting contraindications were excluded. A total of 21 patients were enrolled in the study. All patients were treated by full‐endoscopic foraminotomy using large endoscopic trephine. The visual analogue scale (VAS) and Oswestry disability index (ODI) were evaluated preoperatively and at 1, 3, 6 months, and 1 year after the surgery, and the modified MacNab criteria were used to evaluate clinical outcomes at the last follow‐up. There were 10 males and 11 females with a mean age of 66.38 ± 9.51 years. Five patients had a history of lumbar surgery. The mean operative time was 63.57 ± 25.74 min. The mean follow‐up time was 13.29 ± 1.38 months. The mean postoperative hospital stay time was 1.29 ± 0.56 days. The mean preoperative VAS score significantly decreased from 7.38 ± 1.02 to 2.76 ± 1.09 (t = 19.759, P < 0.01), 2.25 ± 1.02 (t = 21.508, P < 0.01), 1.60 ± 1.05 (t = 31.812, P < 0.01), and 1.45 ± 1.10 (t = 25.156, P < 0.01) at 1 month, 3 months, 6 months, and 1 year after the operation. The mean preoperative ODI score significantly decreased from 64.66% ± 4.91% to 30.69% ± 4.59% (t = 33.724, P < 0.01), 29.44% ± 4.50% (t = 32.117, P < 0.01), 24.22% ± 4.14% (t = 33.951, P < 0.01), and 22.44% ± 4.94% (t = 30.241, P < 0.01) at 1 month, 3 months, 6 months, and 1 year after the operation. At the last follow‐up, 19 patients (90.48%) got excellent or good outcomes. One patient suffered postoperative dysesthesia, and the symptoms were controlled by conversion treatment. One patient took revision surgery due to the incomplete decompression. There were no other major complications. Percutaneous endoscopic decompression is minimally invasive spine surgery. However, the application of endoscopic decompression for L5S1 foraminal stenosis is relatively difficult due to the high iliac crest and narrow foramen. Full‐endoscopic foraminotomy with the large endoscopic trephine is an effective and safe technique for the treatment of degenerative lumbar foraminal stenosis. 相似文献
96.
Jian Qian Qian Zhang Qiang Cao Jie Jiang Pu Li Meiling Bao Chao Qin Zengjun Wang Lixin Hua Pengfei Shao 《Translational andrology and urology》2021,10(3):1030
BackgroundThis study investigated a comfortable suture angle (CSA) with optimized trocar position for closing the defect during renorrhaphy in retroperitoneal laparoscopic partial nephrectomy (LPN). The feasibility, usefulness, and safety of achieving the CSA with modified trocar position were determined for different tumor types.MethodsTwo optimized trocar positions were introduced for different tumor types. A suture angle was based on the tumor plane of the superficial parenchyma defect and the line formed by the needle holder. Preliminary surgical simulations determined a CSA that combined the least suture time with the greatest ease of performance. Achieving the CSA was attempted during renorrhaphy of 106 enrolled patients undergoing retroperitoneal LPN. Patients’ characteristics, operative features, and follow-up information were collected and analyzed.ResultsFor 89 (83.96%) patients, a CSA was successfully reached and parenchyma recovered. The remaining 17 patients were successfully sutured, but the attempt to achieve a CSA failed. For the CSA group, the suture, clamping, and overall operative times were significantly less than that of the non-CSA patients. The groups were similar regarding estimated blood loss, positive surgical margin, and rates of glomerular filtration reduction and complications. Univariable analyses determined that tumor location, growth pattern, and R.E.N.A.L. nephrometry score (RNS) may influence the success of this approach. Multivariable analyses indicated that only tumor location and RNS were independent factors affecting successful achievement of the CSA.ConclusionsThrough different kidney position changes, the CSA could be used to ease the suture process. It is feasible and safe to perform a CSA with optimized trocar position during LPN. Tumor location and RNS may influence the approach to get a CSA. 相似文献
97.
目的 了解我国≥40岁吸烟人群烟草依赖情况及其影响因素,为我国广泛开展戒烟干预提供科学数据。方法 本研究数据来源于2014-2015年中国居民慢性阻塞性肺疾病监测,覆盖31个省(自治区、直辖市)的125个监测点,以面对面询问调查的方式收集≥40岁居民吸烟和烟草依赖的相关变量。应用复杂抽样加权估计我国≥40岁现在吸烟和现在每日吸烟人群烟草依赖率及其95%CI并分析其影响因素。结果 纳入分析现在吸烟者22 380人,现在每日吸烟者19 999人。≥40岁现在吸烟人群的重度烟草依赖率为31.1%(29.3%~32.9%),其中男性为32.0%(30.2%~33.9%),高于女性17.6%(13.4%~21.7%);乡村为32.7%(30.2%~35.2%),高于城镇;40~59岁年龄组重度烟草依赖率较高,为33.3%(31.3%~35.2%)。≥40岁现在每日吸烟人群的重度烟草依赖率为35.0%(33.0%~37.0%),男性为35.8%(33.8%~37.8%),女性为22.0%(16.8%~27.2%)。在现在吸烟人群和每日吸烟人群中,文化程度越低,重度烟草依赖率越高;18岁以前开始吸烟者重度烟草依赖率明显高于18岁及以后开始吸烟者;有慢性呼吸道症状者的重度烟草依赖率明显高于无症状吸烟者;慢性呼吸系统疾病患者和非患者的重度烟草依赖率差异无统计学意义(P>0.05);患有糖尿病、心脑血管疾病和高血压的吸烟者的重度烟草依赖率略低于非患者(P<0.05)。多因素logistic回归分析结果显示,男性、中部和东部地区、40~59岁年龄组、从事农林牧渔水利、生产运输和商业服务职业、文化程度低、18岁以前开始吸烟者患重度烟草依赖的风险高。结论 我国≥40岁吸烟人群的重度烟草依赖水平较高,戒烟干预服务客观需求巨大,应采取有效措施推动我国戒烟干预工作的开展。 相似文献
98.
目的 采用廉价的CaCO_3和CaHPO_4·2H_2O作为原料,在激光的作用下通过反应制备HA生物陶瓷涂层。方法 利用X射线衍射仪和电子探针分析仪对涂层进行相分析、组织观察和成分分析。结果CaCO_3和CaHPO_4·2H_2O按20:80的质量比混合时,在功率为600W、扫描速度为3.5mm/s的激光作用下可一步合成钙磷生物陶瓷涂层。结论 在一定实验条件下,CaCO_3和CaHPO_4·2H_2O可合成组织致密、结合状态良好的钙磷生物陶瓷涂层。 相似文献
99.
利用旋转壁式生物反应器(Rotating wall vessel,RWV)体外培养脐带血干细胞,使其大量扩增,以满足临床应用对造血干/祖细胞的数量与质量要求。从脐带血分离得到的单个核细胞(Mononuclear cells,MNC)在T-flask中培养24h,之后接种到RWV反应器中,培养200h。每24h细胞计数,测量培养基的pH和渗透压变化;在144h和197h测CD34 细胞含量并做CFU-GM半固体培养。有核细胞(Nucleated cells,NC)与CD34 细胞在第197h,分别扩增了435.5±87.6倍和32.7±15.6倍,CFU-GM(Colony-forming unit-granulocyte/macrophage)细胞扩增了21.7±4.9倍。整个培养过程中,RWV反应器中的pH和渗透压都保持在造血细胞最佳的扩增条件内,pH基本保持在7.2~7.4之间,渗透压基本保持在290~310mmol/kg之间。由于旋转壁式生物反应器(RWV)结构上的特殊性,可以保证细胞在悬浮流动的状态下生长,很好地模拟了脐带中的造血微环境,使脐带血造血干细胞在该反应器中短期内得到大量扩增。 相似文献
100.
实验用荧光素Bb逆行追踪方法,研究了褐云玛瑙螺支配大触角肌肉活动的神经元在中枢的分布,结果表明,Bb标记神经元大多分布于同侧脑节,少量分布于侧脑节,同侧口球节,足节和侧节,Bb标记神经元大多为中小型神经元,个别属于大型神经元。 相似文献