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1.
中药经典名方开发已成为当下中医药界研究的热点之一,而其中经典名方物质基准的成功研制对于整个中药经典名方的申报极为关键。经典名方物质基准既是检测经典名方制剂质量的基准,同时又需反映整方的物质基础。中药成分众多而复杂,单成分的、化药式的研发与质量控制模式难以适用于整体药用的中药制剂的开发,亟需开辟一条中药专属的研发模式。以目前已有的现代科学技术,笔者建议将中药的遗传多态性、提取动力学、指纹图谱总量统计矩(相似度)法、超分子"印迹模板"等结合应用于经典名方物质基准的研制,探讨中药经典名方物质基准的质量控制技术,以期全面、准确地阐明药材-饮片-物质基准的成分群量值的传递规律,为推进中药经典名方的研制进程提供参考。 相似文献
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3.
目的 构建基于超分子“气析”理论的中药制剂的靶向性评价方法,并对柴胡影响片仔癀的肝靶向性进行研究。方法 采用分子连接性指数分析主要归肝经的药材、片仔癀中的各成分“印迹模板”特征及肝靶向趋势;利用中药多成分“印迹模板”自主作用特征,结合靶区动力学和总量统计矩原理建立中药制剂的靶向性评价方法,并对片仔癀组、柴胡组、片仔癀+柴胡组、空白组4组作用的肝癌大鼠进行实验验证。结果 扣除主要归肝经药材分子连接性指数平均值后,片仔癀组与柴胡组的分子连接性指数相似度0.376 8,片仔癀+柴胡组与柴胡组的分子连接性指数相似度0.988 2,预测柴胡可增强片仔癀的肝靶向性。建立中药复方靶向性的评价体系,包括相对总量摄取率(RUET),相对总量浓度(RCT),相对“印迹”趋势(RITT)及相对“印迹”方差(RIVT);各组织中肝脏的RUET和RCT均为最大(RUET=1.88>1,RCT=2.30>1),其他组织这2个参数则均<1,说明片仔癀结合柴胡后能增加其在肝脏的分布,肝靶向性增强;除血浆外,其他组织的RITT及RIVT均在1.0附近波动,说明靶向修饰不改变片仔癀的“印迹”作用趋势,对成分种类也无明显影响。结论 在超分子“气析”理论指导下,可建立以分子连接性指数和总量统计矩参数表征中药制剂多成分“印迹”作用的靶向性评价参数体系,实现对中药制剂靶向性的评价,柴胡的加入可增加片仔癀的肝靶向性。 相似文献
4.
《International journal of oral and maxillofacial surgery》2019,48(8):1028-1031
Suspicious radiological findings in the jaw bone require histopathological examination for the confirmation of a diagnosis. As pathologies in this region are difficult to reach or are in close proximity to relevant anatomical structures, e.g. tooth roots or nerves, they often represent a challenge. Such factors may adversely affect the predictability of the surgical outcome of a biopsy of the osseous tissues. This technical note introduces a novel method for performing a digitally planned, guided biopsy. For this purpose, a cone beam computed tomography scan and an intraoral scan are superimposed using specific planning software. The resulting three-dimensionally printed, tooth-supported drilling template is designed for a trephine biopsy. It allows a precise, minimally invasive approach, with an exact three-dimensional determination of the biopsy location prior to surgery. The risk of devitalization of the neighbouring teeth or possible damage to the nerve structures can be minimized. Furthermore, a small access flap can be sufficient. In summary, the method of bone biopsy presented here allows high precision and greater predictability for biopsy sampling and is minimally invasive for the patient. 相似文献
5.
Cynthia Aristei Valentina Lancellotta Marco Piergentini Giacomo Costantini Simonetta Saldi Sara Chierchini Antonella Cavalli Luca Di Renzo Oscar Fiorucci Massimo Guasticchi Vittorio Bini Alessandro Ricci 《Brachytherapy》2019,18(1):57-62
Purpose
High-dose-rate, multicatheter interstitial brachytherapy is technically complex and operator-dependent, requiring lengthy training and specialized skills. Furthermore, until the advent of contouring on computerized tomography (CT) images, difficulties existed in locating the target volume precisely. The present article reports the results of a study that aimed at producing and validating a 3D-printed template to aid in target volume localization for multicatheter interstitial brachytherapy in patients with breast cancer.Methods and Materials
Thirteen patients, candidates for accelerated partial breast irradiation or boost, were enrolled in the study. The target volume was defined on CT slices, and a template with empty spaces corresponding to the target volume projection on the patient's skin was produced by a 3D printer. The procedure was compared with the standard method followed in our center (1) visually, by assessing overlap between the target volume projections on the patient's skin, (2) by X-ray findings, and (3) by intraclass correlation coefficient.Results
Visual assessment and X-ray findings showed the 3D-printed target volume always fell within the standard volume in all 13 patients. The intraclass correlation coefficient indicated moderate agreement for both the medial and the lateral skin projections.Conclusions
The 3-D printed templates constitute a quick, easy, and reliable method to localize the target volume for high-dose-rate interstitial multicathether brachytherapy in patients with breast cancer and can safely be used in clinical practice. 相似文献6.
《Drug metabolism and pharmacokinetics》2020,35(3):253-265
Modes of interactions of small ligands with CYP3A4 have been defined using the Template established in our previous studies (DMPK. 34: 113–125 2019 and 34 351–364 2019). Interactions of polyaromatic hydrocarbons such as benzo[a]pyrene, pyrene and dibenzo[a,j]acridine were refined with the idea of Right-side movement of ligands at Rings A and B of Template. Expected formation of metabolites from the placements faithfully matched with experimentally observed sites of their metabolisms and also with preferred orders of regio-isomeric metabolite abundances in recombinant CYP3A4 system. In comparison of CYP3A4-ligand data with the placements on simulations, a futile sitting of non-substituted and free rotatable phenyl structures was suggested as a cause of poor oxidations of the phenyl parts of CYP3A4 ligands. These data were in turn indicative of the role of the rotation-ceasing action for the function. Typical inhibitors, ketoconazole, nicardipine, mibefradil and GF-I-1 shared mutuality on their sittings, in which the inhibitor molecules hold a CYP3A4 residue from dual sides on Template. In addition, clotrimazole would be stuck between facial- and rear-side walls of CYP3A4 and interact with ferric iron through nitrogen atom of the imidazole part. These data offered structural bases of CYP3A4-inhibitory actions of ligands. 相似文献
7.
《International journal of oral and maxillofacial surgery》2020,49(10):1379-1384
Three-dimensional stereophotogrammetry is commonly used to assess volumetric changes after facial procedures. A lack of clear landmarks in aesthetic regions complicates the reproduction of selected areas in sequential images. A three-dimensional volumetric analysis was developed based on a personalized aesthetic template. The accuracy and reproducibility of this method were assessed. Six female volunteers were photographed using the 3dMDtrio system according to a clinical protocol, twice at baseline (T1) and twice after 1 year (T2). A styrofoam head was used as control. A standardized aesthetic template was morphed over the baseline images of the volunteers using a coherent point drift algorithm. The resulting personalized template was projected over all sequential images to assess surface area differences, volume differences, and root mean square errors. In 12 well-defined aesthetic areas, mean average surface area and volume differences between the two T1 images ranged from −7.6 mm2 to 10.1 mm2 and −0.11 cm3 to 0.13 cm3, respectively. T1 root mean square errors ranged between 0.24 mm and 0.62 mm (standard deviation 0.18–0.73 mm). Comparable differences were found between the T2 images. An increase in volume between T1 and T2 was only observed for volunteers who gained in body weight. Personalized aesthetic templates are an accurate and reproducible method to assess changes in aesthetic areas. 相似文献
8.
The Neck Imaging Reporting and Data System (NI-RADS) was conceived in 2016 with the objective of standardizing assessment and reporting in surveillance imaging for patients with head and neck squamous cell carcinomas and their subsequent management. The goals are to simplify radiology reports while increasing the consistency and accuracy of the interpretation of cancer surveillance imaging; enable better communication among clinicians and between clinicians and patients; facilitate outcomes research; and ultimately improve patient survival, morbidity, and mortality. The objective of the current study was to provide the background as to why and how NI-RADS was conceived and what it entails in radiology reporting. 相似文献
9.
基于3D软组织打印技术经皮穿刺中上胸椎椎弓根入路椎体成形术导向模板的初步研制 总被引:1,自引:1,他引:0
目的:观察数字化导向模板技术和3D软组织打印制作的个体化经皮穿刺中上胸椎椎弓根入路椎体成形术数字化导向模板的可行性。方法:回顾性选择20例中上胸椎骨折患者CT扫描数据。将数据输入3D打印机打印1∶1带软组织胸椎模型,并应用Mimics 15.0软件中3-matic模块设计中上胸椎体表椎弓根钉道及相应导向模板,3D打印机打印导向模板并固定带软组织胸椎模型后置入2.0 mm克氏针,CT扫描观察穿刺针的准确性,通过穿刺管注入骨水泥并用影像学进行验证,记录带软组织中上胸椎模型的打印时间、钉道设计及体表导向模板制作时间以及费用。结果:3D打印的一体化胸椎模型及数字化经皮穿刺中上胸椎椎弓根入路数字化导向模板能够满足中上胸椎经皮穿刺椎体成形术穿刺的要求,导板与皮肤表面贴合良好,骨水泥充盈良好。中上胸椎模型的打印时间及钉道设计、手术导向模板制作时间分别为(719.00±3.03) min,(12.30±1.01) min和(55.50±10.30) min,平均费用约为3 150元。结论:基于3D软组织打印技术的个性化经皮穿刺中上胸椎椎弓根导向模板可实现经皮穿刺的精确置入。 相似文献
10.
目的 制备桑色素-Cu2+配位分子印迹聚合物,对桑枝中桑色素进行分离富集。方法 在Cu2+存在下,丙烯酰胺为功能单体,在水-甲醇极性溶剂中制备桑色素-Cu2+配位分子印迹聚合物,以该聚合物为填料固相萃取桑枝中桑色素。结果 所制备配位分子印迹聚合物对桑色素具有较强的特异性、选择性吸附,最大吸附量82 μmol/g,远大于以氢键为作用力的传统印迹聚合物及非印迹聚合物;对桑色素结构类似物大豆素、儿茶素的分离因子分别为4.81、4.02。对比桑枝固相萃取淋洗液、洗脱液组成,所制备配位印迹聚合物对桑枝中桑色素表现出明显的富集效果。结论 制备的桑色素配位分子印迹聚合物环境适应性好,选择性吸附能力强,是适用于天然产物有效成分桑色素分离富集的良好材料。 相似文献