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991.
动物胶类药物在很多疾病的治疗和保健中发挥重要作用。许多古籍中均有以胶类入方治疗疾病的记载。近年来,胶类药物的相关研究逐渐增多,应用领域也在不断扩大。笔者通过对常用胶类药物的发展变化、药性归经、现代药理作用、临床应用、胶类新药开发前景、质量控制方法等方面的分析总结,整理出胶类中药的发展变迁及现代研究进展,为今后胶类药物的开发利用提供参考。 相似文献
992.
糖尿病(DM)是以慢性高血糖为主要特征的多病因的代谢性疾病,其并发症如冠状动脉粥样硬化、肾病、足病和心脏功能障碍等具有较高的发病率、致残率和致死率。DM及其并发症病程长、易反复,难以根治,严重影响人民生命健康。NOD样受体热蛋白结构域3(NLRP3)炎症小体是炎症反应和先天免疫系统重要组成,其激活后诱发的炎症级联反应通过释放炎症因子、损伤内皮细胞、影响代谢应激等参与DM及其并发症的发生和发展。因此,作为炎症反应的核心,NLRP3炎症小体可能为DM及其并发症疾病的治疗提供新的靶点。中医药作为祖国医学的重要组成部分,在DM及其并发症的治疗中扮演着重要角色,并对NLRP3炎症小体具有调节作用,调控NLRP3炎症小体已成为中药防治DM及其并发症新的研究策略。但目前,从NLRP3炎症小体角度探究中医药治疗DM及其并发症作用报道相对零散,且缺乏系统综述。因此,该文通过分析汇总近年来国内外文献,从NLRP3炎症小体对DM及其并发症发生发展的影响和中医药经NLRP3炎症小体干预DM及其并发症进展两方面进行阐述,为中药对NLRP3炎症小体调控研究提供参考资料,以期为DM及其并发症的治疗提供新的方向。 相似文献
993.
Qiaozhen Wang Xiaolong Tang Ping Dai Chuanxi Wang Weiyang Zhang Guodong Chen Kui Hong Dan Hu Hao Gao Xinsheng Yao 《药学学报(英文版)》2021,11(2):588
Organic carbonates (OCs) are a class of compounds featured by a carbonyl flanked by two alkoxy/aryloxy groups. They exist in either linear or cyclic forms, of which the majority encountered in nature adopt a pentacyclic structure. However, the enzymatic basis for pentacyclic carbonate ring formation remains elusive. Here, we reported that a four-protein metabolon (AlmUII–UV) assembled by a small peptide protein (AlmUV) appends a reactive N-hydroxylcarbamoyl moiety to the decarboxylated aldgamycins followed by a non-enzymatic condensation to give the pentacyclic carbonate ring. Our results have documented an unprecedent mechanism for carbonate formation.KEY WORDS: Aldgamycins, Biosynthesis, N-hydroxylcarbamoyl, Organic carbonate, Protein complex 相似文献
994.
995.
Eitan Prisman Marat Slessarev Takafumi Azami Dan Nayot Michael Milosevic 《International journal of radiation biology》2013,89(7):457-462
Purpose: Carbogen has long been under investigation as an adjuvant to radiotherapy of tumors. A major factor confounding its evaluation is its inconsistency in raising blood partial pressure of CO2 (pCO2). We investigated whether a new partial rebreathing method would provide better control of pCO2 than carbogen.Methods and materials: We compared the efficacy of each method in 10 healthy volunteers. Volunteers breathed 1.5, 3 and 5% carbogen in 5-min stages via the usual non-rebreathing circuit. All the volunteers then breathed 100% O2 through a commercial sequential gas delivery (SGD) circuit modified by attaching a reservoir to its exhalation port. Hypercarbia was induced by step reductions in oxygen flow to the SGD circuit. We monitored minute ventilation and end-tidal pCO2 (ETpCO2) as a surrogate for its arterial value.Results: Inhalation of 1.5 and 3% carbogen did not increase ETpCO2 from baseline (40 ± 1.5 mmHg); 5% carbogen increased ETpCO2 to 45 ± 1.6 mmHg (p < 0.001). With the SGD circuit, reducing O2 flow to 4.3 ± 0.7 l/min increased ETpCO2 in all subjects from 41 ± 2.0 mmHg (baseline) to 46 ± 2.1 mmHg (p < 0.001). Voluntary hyperventilation reduced ETpCO2 with 5% carbogen but not with SGD (p = 0.379).Conclusions: We confirm previous observations that carbogen inhalation does not result in a predictable rise in ETpCO2 and suggest that a precise and stable target ETpCO2 can instead be induced by simply controlling O2 flow into a modified SGD circuit. We hoped that the reliable control of pCO2 will enable studies that address first, the efficacy of raising ETpCO2 on specific tumor blood flow, and eventually, its benefit as an adjuvant to radiotherapy. 相似文献
996.
998.
Tingting Qiao Simin Liu Zhijun Cui Xiaqing Yu Haidong Cai Huijuan Zhang Ming Sun Zhongwei Lv Dan Li 《The Journal of international medical research》2021,49(1)
ObjectiveTo construct deep learning (DL) models to improve the accuracy and efficiency of thyroid disease diagnosis by thyroid scintigraphy.MethodsWe constructed DL models with AlexNet, VGGNet, and ResNet. The models were trained separately with transfer learning. We measured each model’s performance with six indicators: recall, precision, negative predictive value (NPV), specificity, accuracy, and F1-score. We also compared the diagnostic performances of first- and third-year nuclear medicine (NM) residents with assistance from the best-performing DL-based model. The Kappa coefficient and average classification time of each model were compared with those of two NM residents.ResultsThe recall, precision, NPV, specificity, accuracy, and F1-score of the three models ranged from 73.33% to 97.00%. The Kappa coefficient of all three models was >0.710. All models performed better than the first-year NM resident but not as well as the third-year NM resident in terms of diagnostic ability. However, the ResNet model provided “diagnostic assistance” to the NM residents. The models provided results at speeds 400 to 600 times faster than the NM residents.ConclusionDL-based models perform well in diagnostic assessment by thyroid scintigraphy. These models may serve as tools for NM residents in the diagnosis of Graves’ disease and subacute thyroiditis. 相似文献
999.
Heather K. Knych Rick M. Arthur Kirsten L. Kanarr Dan S. McKemie Philip H. Kass 《Drug testing and analysis》2019,11(9):1431-1443
Methamphetamine is a central and peripheral nervous system stimulant. There is only a single study that describes exposure to and disposition of this compound in horses. The potential for abuse and inadvertent exposure in equine athletes along with the limited data available necessitates further study. The objectives of the current study were to describe drug and metabolite concentrations, develop an analytical method that could be used to regulate its use, and describe selected pharmacodynamic effects. In phase 1, six horses were randomized into three transmucosal dose groups (n = 2/group; 0.5, 1.0 or 10 mg). In phase 2, horses received a single 10 mg intravenous dose. In phase 3, the effects of urinary pH on elimination were studied. Blood and urine samples were collected for up to 72 hours post drug administration. Concentrations of methamphetamine were measured using liquid chromatography–tandem mass spectrometry. Methamphetamine was below the limit of detection (LOD) in blood by 2, 4, and 18 hours following transmucosal administration of 0.5, 1, and 10 mg, respectively. Following intravenous administration, methamphetamine fell below the LOD between 12 and 18 hours. Following urinary acidification, methamphetamine fell below the limit of quantitation (LOQ) by 12 hours. In urine, methamphetamine was no longer detected at 48, 48, and 72 hours in the 0.5, 1, and 10 mg transmucosal groups and 18 hours in the intravenous group. Increased urinary pH resulted in urinary concentrations of methamphetamine falling below detectable levels by 48 hours post transmucosal administration. While the number of animals was small, behavioral, stimulatory, and cardiac effects were minimal. 相似文献
1000.
苗野 《中国继续医学教育》2020,(8):14-16
目的探讨神经外科教学中虚拟现实技术、Seminar模式的应用效果。方法选取本院2014级临床专业实习学生24人,随机选取12人作为对照组,采用传统教学法;12人为观察组,采用虚拟现实技术、Seminar模式教学法。比较两组学生的病理分析能力,多学科协作能力,临床操作能力。结果观察组理论考试和操作考试评分分别为(84.5±3.9)分、(86.3±2.7)分,对照组分别为(80.2±2.8)分、(80.0±2.1)分,观察组理论考试和操作考试评分均高于对照组(P<0.05)。观察组病情分析、临床操作、手术胜任和多学科协作能力评分分别为(1.8±0.7)分、(1.7±0.5)分、(1.6±0.4)分、(1.5±0.5)分;对照组分别为(1.2±0.4)分、(1.1±0.2)分、(1.0±0.3)分、(1.1±0.2)分,观察组病情分析、临床操作、手术胜任和多学科协作能力评分均高于对照组(P<0.05)。结论虚拟现实技术、Seminar模式教学法联合应用提高学生的学习主动性、理论知识水平和实践技能操作水平,提高了神经外科教学效果。 相似文献