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排序方式: 共有10000条查询结果,搜索用时 62 毫秒
1.
目的 制定刺梨药材质量标准,用于刺梨的生产、监督、流通及使用等各环节的质量控制。方法 参照《中国药典》通用检测方法及相关指导原则分别制定刺梨的水分、总灰分、浸出物限度;采用特征图谱以及薄层色谱法控制刺梨整体质量。结果 刺梨特征图谱中应呈现6个特征峰,并应与对照药材参照物色谱峰中的5个特征峰保留时间相对应,另有1峰应与加入的异槲皮苷对照品参照物峰保留时间相对应。水分不得过14.0%,总灰分不得过5.0%,醇溶性浸出物不少于20.0%。结论 实验所建立的刺梨质量标准符合国家有关中药质量标准制定要求,能够以标准的形式对刺梨的质量进行控制。  相似文献   
2.
目的 建立细叶亚菊的质量标准,为其质量控制和合理开发利用提供科学参考。方法 采用性状鉴别、显微鉴别、薄层色谱法(TLC)对细叶亚菊进行定性分析;参照《中国药典》(2020年版)通则方法对细叶亚菊水分、总灰分、酸不溶性灰分、水溶性浸出物进行含量检查;利用高效液相色谱法(HPLC)测定细叶亚菊中绿原酸、异绿原酸A的含量。结果 确定了细叶亚菊的药材性状及显微特征。TLC鉴别显示,供试品(细叶亚菊药材)与对照品(绿原酸、异绿原酸A)在相应位置上均显示相同颜色的荧光斑点。13批细叶亚菊水分、总灰分、酸不溶性灰分、浸出物的含量分别为8.55%-13.07%、6.81%-12.68%、1.11%-3.53%、8.41%-11.64%;绿原酸、异绿原酸A的含量范围分别为0.072%-0.440%、0.283%-1.324%(n=3)。结论 本研究建立的方法准确稳定,可为细叶亚菊的质量控制提供参考。暂规定细叶亚菊水分不得过12.0%,总灰分不得过10.0%,酸不溶性灰分不得过2.5%,水溶性浸出物不得少于8.0%,绿原酸不得少于0.2%,异绿原酸A不得少于0.6%。  相似文献   
3.
Mass characteristic frequency (fmass) is a novel shear wave (SW) parameter that represents the ratio of the averaged minimum SW speed within the regions of interest to the largest dimension of the mass. Our study objective was to evaluate if the addition of fmass to conventional 2-D shear wave elastography (SWE) parameters would improve the differentiation of benign from malignant thyroid nodules. Our cohort comprised 107 patients with 113 thyroid nodules, of which 67 (59%) were malignant. Two-dimensional SWE data were obtained using the Supersonic Imagine Aixplorer ultrasound system equipped with a 44- to 15-MHz15-MHz linear array transducer. A receiver operating characteristic curve was generated based on a multivariable logistic regression analysis to evaluate the ability of SWE parameters with/without fmass and with/without clinical factors to discriminate benign from malignant thyroid nodules. The addition of fmass to conventional SW elasticity parameters increased the area under the curve from 0.808 to 0.871 (p = 0.02). The combination of SW elasticity parameters plus fmass plus clinical factors provided the strongest thyroid nodule malignancy probability estimate, with a sensitivity of 93.4% and specificity of 91.1% at the optimal threshold. In summary, fmass can be a valuable addition to conventional 2-D SWE parameters.  相似文献   
4.
PurposeTo assess the safety and tolerability of a vandetanib-eluting radiopaque embolic (BTG-002814) for transarterial chemoembolization (TACE) in patients with resectable liver malignancies.Materials and MethodsThe VEROnA clinical trial was a first-in-human, phase 0, single-arm, window-of-opportunity study. Eligible patients were aged ≥18 years and had resectable hepatocellular carcinoma (HCC) (Child-Pugh A) or metastatic colorectal cancer (mCRC). Patients received 1 mL of BTG-002814 transarterially (containing 100 mg of vandetanib) 7–21 days prior to surgery. The primary objectives were to establish the safety and tolerability of BTG-002814 and determine the concentrations of vandetanib and the N-desmethyl vandetanib metabolite in the plasma and resected liver after treatment. Biomarker studies included circulating proangiogenic factors, perfusion computed tomography, and dynamic contrast-enhanced magnetic resonance imaging.ResultsEight patients were enrolled: 2 with HCC and 6 with mCRC. There was 1 grade 3 adverse event (AE) before surgery and 18 after surgery; 6 AEs were deemed to be related to BTG-002814. Surgical resection was not delayed. Vandetanib was present in the plasma of all patients 12 days after treatment, with a mean maximum concentration of 24.3 ng/mL (standard deviation ± 13.94 ng/mL), and in resected liver tissue up to 32 days after treatment (441–404,000 ng/g). The median percentage of tumor necrosis was 92.5% (range, 5%–100%). There were no significant changes in perfusion imaging parameters after TACE.ConclusionsBTG-002814 has an acceptable safety profile in patients before surgery. The presence of vandetanib in the tumor specimens up to 32 days after treatment suggests sustained anticancer activity, while the low vandetanib levels in the plasma suggest minimal release into the systemic circulation. Further evaluation of this TACE combination is warranted in dose-finding and efficacy studies.  相似文献   
5.
6.
Background and aimsIntermittent fasting reduces risk of interrelated cardiometabolic diseases, including type 2 diabetes and heart failure (HF). Previously, we reported that intermittent fasting reduced homeostasis model assessment of insulin resistance (HOMA-IR) and Metabolic Syndrome Score (MSS) in the WONDERFUL Trial. Galectin-3 may act to reduce insulin resistance. This post hoc evaluation assessed whether intermittent fasting increased galectin-3.Methods and resultsThe WONDERFUL Trial enrolled adults ages 21–70 years with ≥1 metabolic syndrome features or type 2 diabetes who were not taking anti-diabetic medication, were free of statins, and had elevated LDL-C. Subjects were randomized to water-only 24-h intermittent fasting conducted twice-per-week for 4 weeks and once-per-week for 22 weeks or to a parallel control arm with ad libitum energy intake. The study evaluated 26-week change scores of galectin-3 and other biomarkers. Overall, n = 67 subjects (intermittent fasting: n = 36; control: n = 31) completed the trial and had galectin-3 results. At 26-weeks, the galectin-3 change score was increased by intermittent fasting (median: 0.793 ng/mL, IQR: ?0.538, 2.245) versus control (median: ?0.332 ng/mL, IQR: ?0.992, 0.776; p = 0.021). Galectin-3 changes correlated inversely with 26-week change scores of HOMA-IR (r = ?0.288, p = 0.018) and MSS (r = ?0.238, p = 0.052). Other HF biomarkers were unchanged by fasting.ConclusionA 24-h water-only intermittent fasting regimen increased galectin-3. The fasting-triggered galectin-3 elevation was inversely correlated with declines in HOMA-IR and MSS. This may be an evolutionary adaptive survival response that protects human health by modifying disease risks, including by reducing inflammation and insulin resistance.Trial registrationClinicaltrials.gov, NCT02770313 (registered on May 12, 2016; first subject enrolled: November 30, 2016; final subject's 26-week study visit: February 19, 2020).  相似文献   
7.
目的 调查住院患者接受达格列净治疗的情况,了解该药的应用现状和不良反应并分析其危险因素,为规范其临床合理应用提供依据。方法 检索PubMed、中国知网、万方和维普数据库,汇总国内外达格列净相关指南、文献和专家共识,形成达格列净临床应用的合理性评价标准。回顾性调查广州医科大学附属第二医院2021年3月1日—2022年2月28日住院患者使用达格列净的情况,按照已制定的评价标准进行合理性和安全性分析,并提出合理化用药建议。结果 共有201例患者应用了达格列净,其中有效病例198例,不合理用药病例共27例,不合理使用率为13.64%,以用药时机不适宜、禁忌证用药和特殊人群用药不合理为主要原因。不良反应共6例,发生率为3.03%,以泌尿系感染、糖尿病酮症和糖尿病酮症酸中毒等不良反应为主。结论 达格列净降低血糖和改善心力衰竭预后的作用越来越受到临床医生重视,临床用药期间应多关注患者的血β-羟基丁酸和肝肾功能指标,关注达格列净的用药时机、特殊人群用药和不良反应等方面。针对其不合理应用情况和不良反应,临床药师应结合达格列净新修订的说明书、临床指南和专家共识等最新信息,制定合理性评价标准和用药建议,做到实时点评,进一步促进钠–葡萄糖共转运蛋白2抑制剂(SGLT2i)的合理使用。  相似文献   
8.
目的:观察临床循证护理对颅内动脉瘤手术后患者睡眠质量的影响。方法:选取2018年12月至2019年3月期间在联勤保障部队第909医院进行了颅内动脉瘤手术治疗的76例患者,采用双盲法将患者随机分为对照组和观察组,每组38例。对照组使用常规护理,观察组使用临床循证护理,比较2组患者的睡眠质量、生命质量以及不良情绪评分。结果:对照组患者的入睡时间、夜间苏醒、比期望的时间早睡、总睡眠时间、白天情绪、白天身体功能以及白天思睡评分均高于观察组(P<0.05)。对照组患者总体健康、生理功能、生理职能、躯体疼痛、活力、社会功能、情感职能以及情感健康在内的八项评分均低于观察组(P<0.05)。护理后,对照组患者SAS、SDS评分均高于观察组(P<0.05)。结论:临床循证护理措施可以改善颅内动脉瘤手术后患者的睡眠质量、增加生命质量并有效缓解患者不良情绪,值得推广。  相似文献   
9.
PurposeTo compare the characteristics of polidocanol (POL) and ethanolamine oleate (EO) sclerosing foams produced by a Shirasu porous glass membrane (SPGM) device with those made using a 3-way stopcock (3WSC).Materials and MethodsFoam half-life times were measured in an ex-vivo benchtop study. Computed tomography (CT) images of each foam were obtained over the time course, and a CT texture analysis was conducted. The bubble size in each foam was measured by an optical microscope.ResultsMedian foam half-life times were longer in the SPGM group than in the 3WSC group (POL: 198 vs 166 s, P = .02; EO: 640 vs 391 s, P < .01). In the CT texture analysis, median standard deviation (SD) and entropy (randomness) were lower, and median energy (uniformity) and gray-level cooccurrence matrix (GLCM) homogeneity were higher in the SPGM group than in the 3WSC group (POL SD: at 30 s and 50–300 s; POL entropy: at 0–60 s; EO SD: at 0–600 s; EO entropy: at 0–460 s; POL energy: at 0–40 s; POL GLCM homogeneity: at 0–250 s; EO energy: at 0–360 s; EO GLCM homogeneity: at 0–480 s; all P < .05). Median bubble diameters in the SPGM group and in the 3WSC group were 69 and 83 μm (P < .01), respectively, in the POL foam; and 36 and 36 μm (P = .45), respectively, in the EO foam.ConclusionsPOL and EO foams had greater uniformity and longer foam half-life time when prepared with an SPGM device than with a 3WSC.  相似文献   
10.
《Saudi Dental Journal》2022,34(5):346-354
BackgroundLipopolysaccharides (LPS) stimulate production of inflammatory cytokines. Chrysin is flavonoid beneficial for treatment of inflammatory conditions. Bone marrow mesenchymal stem cell (BM-MSC) exosomes have regenerative ability in different tissues.ObjectiveTo assess potential role of chrysin and BM-MSC exosomes on ultra-structure, viability and function of human dermal fibroblasts-adult (HDFa) stimulated by LPS.MethodsHDFa cells were divided into: Group I: Cells received no treatment. Group II: Cells were stimulated with LPS. Group III: LPS stimulated cells were treated with chrysin. Group IV: LPS stimulated cells were treated with exosomes.ResultsAfter 48 h, ultrastructural examination of HDFa cells in Group I revealed intact plasma membrane and numerous cytoplasmic organelles. Group II displayed destructed plasma membrane and apoptotic bodies. Group III showed intact plasma membrane with loss of its integrity at some areas. Group IV demonstrated intact plasma membrane that showed fusion with exosomes at some areas. Statistical analysis of MTT represented highest mean value of cell viability% in Group IV followed by Groups III, I and II respectively. Statistical analysis of enzyme-linked immunosorbent assay (ELISA) showed the highest mean value of interleukin-1β (IL-1β) was in Group II followed by Groups III, IV and I, while highest mean values of interleukin-10 (IL-10), nuclear factor-erythroid 2-related factor 2 (Nrf2) and heme oxygenase-1 (HO-1) proteins were in Group I, followed by Groups IV, III and II respectively.ConclusionsLPS have harmful consequences on ultra-structure, viability and function of HDFa cells. BM-MSC exosomes have better regenerative action on inflamed fibroblasts in comparison to chrysin.  相似文献   
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