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目的:建立地黄不同炮制品的薄层色谱鉴别方法。方法:以D-果糖、梓醇、蔗糖、棉子糖、水苏糖、蜜二糖及甘露三糖为对照品,考察提取溶剂(水,20%甲醇,50%甲醇,80%甲醇),展开剂(正丁醇-甲醇-三氯甲烷-冰乙酸-水,乙酸乙酯-吡啶-冰乙酸-水,正丁醇-冰乙酸-水),显色剂(苯胺-二苯胺-磷酸溶液,茚三酮溶液),点样量(2,4,6μL),检视条件(日光,日光底部灯,365 nm和254 nm)对薄层色谱分析的影响,确定生地黄及熟地黄饮片的供试品溶液制备方法和最佳薄层色谱条件。结果:采用薄层色谱高效硅胶G板,以正丁醇-甲醇-三氯甲烷-冰乙酸-水(13∶5∶5∶1∶2)为展开剂展开,喷以苯胺-二苯胺-磷酸溶液,110℃下加热显色,于日光底部灯下进行检视,所得地黄不同炮制品薄层色谱分离效果和显色效果较佳,斑点清晰且特征性好。结论:该薄层色谱鉴别方法操作简便易行,定性特征明显、结果直观,可有效鉴别地黄不同炮制品,并可为熟地黄的炮制终点确定提供实验依据。 相似文献
3.
钟恒斯 《中国继续医学教育》2020,(13):155-157
目的为建立众生丸中蒲公英成分的快速定性鉴别方法,采用薄层色谱法(TLC),基于样品与标准品对照,实现快速定性鉴别。方法通过参考有关文献,经过实验,对众生丸中蒲公英成分的提取方法、提取时间、提取溶剂、展开剂的选择、显色剂的选择对实验结果的影响进行研究。结果以乙酸乙酯为溶剂经超声提取、以三氯甲烷为展开剂,喷以10%硫酸乙醇溶液作为显色剂。薄层色谱鉴别斑点清晰,阴性对照无干扰。结论所建立方法操作简单,具有速度快,分离效果、专属性和重现性好的优点,应用于众生丸中蒲公英成分的快速定性鉴别,可加强对众生丸的质量控制。 相似文献
4.
目的:建立黔产红土茯苓药材的质量标准。方法:对不同产地黔产红土茯苓药材进行性状鉴别、显微鉴别、薄层色谱鉴别;参照《中国药典》2015年版四部通则方法对黔产红土茯苓药材水分、总灰分、浸出物进行测定。结果:薄层色谱斑点清晰,分离好,专属性强,无干扰;初步规定黔产红土茯苓药材水分不得过15.0%,总灰分不得过5.0%,水溶性浸出物含量不得少于8.0%。结论:该方法操作简便、结果可靠,能够为黔产红土茯苓药材质量评价提供一定的参考。 相似文献
5.
Abdol-Mohammad Kajbafzadeh Reza Khorramirouz Seyedeh Maryam Kameli Kiarad Fendereski Seyedeh Sima Daryabari Seyed Mohammad Tavangar Bahram Azizi Garajegayeh 《The Journal of thoracic and cardiovascular surgery》2019,157(4):1494-1502
Background
Various investigations have reported that the internal mammary artery (IMA) is an efficient and functional choice of conduit for vascular graft surgeries, especially for coronary artery bypass grafts; however, the quest to find an ideal vascular substitute remains. We hypothesized that acellular IMA could be an appropriate graft for small-diameter vascular bypasses that could be used in various surgeries including coronary artery bypass grafting.Methods
We decellularized human IMAs and performed histologic evaluations and scanning electron microscopy to confirm the decellularization process and the preservation of the extracellular matrix. Subsequently, we grafted the scaffolds into the superficial femoral arteries of 8 New Zealand rabbits with an end-to-end anastomosis. Computed tomography angiograms were provided at 3, 12, and 36 months postoperatively. Subsequently, the animals were killed, and biopsies were taken for histologic and immunohistochemical assessments.Results
Evaluation of the acellular tissue confirmed the efficacy of the decellularization protocol and the preservation of the extracellular matrix. All 8 animals survived the entire follow-up period. Doppler ultrasonography and computed tomography angiographies verified the conduit's patency. Histologic assessments depicted the recellularization of all 3 layers of the scaffold. Smooth muscle cells were detected in tunica media. Immunohistochemical assessments confirmed these findings.Conclusions
In conclusion, we demonstrated that acellular human IMA could be used as an efficient small-diameter vascular substitute with high patency. These findings could pave the path for future investigations on the clinical application of acellular IMA as a novel vascular graft for small-diameter bypass surgeries. 相似文献6.
《Saudi Pharmaceutical Journal》2022,30(6):679-692
Croton stellatopilosus (Plaunoi) leaves accumulate several diterpenes and possess various pharmacological activities. The present study aimed to prepare, characterize and assess the antibacterial activity of inclusion complexes prepared by mixing plaunotol (PL) or plaunoi extract (PE) with cyclodextrins (CD), including α-CD, β-CD, γ-CD, and hydroxypropyl-β-cyclodextrin (HP-β-CD). The inclusion complexes were characterized using SEM, XRD, DSC, and FT-IR and evaluated for aqueous solubility and thermal stability. The PL and PE lyophilized complexes with HP-β-CD were further evaluated for their antibacterial activity against acne-causing bacteria. The minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC) of PL, PE, and the inclusion complexes evaluated using the agar dilution method revealed that the MIC and MBC values of the inclusion complexes were lower than those of PL or PE alone. Interestingly, the complexes had a synergistic activity with clindamycin after testing with checkerboard assay. The hydrogel containing the inclusion complex and clindamycin were assessed for antibacterial activity using the agar well diffusion method. The results indicated that the hydrogels showed significant inhibition of bacterial growth. In conclusion, the prepared solid dispersion of PL or PE with HP-β-CD could enhance antibacterial activity by increasing the drug solubility. The hydrogels containing PL or PE complex and clindamycin could be considered as a candidate for the treatment of acne vulgaris. 相似文献
7.
This article proposes an indirect measurement method based on a dimensional and shape analysis of forgings for the evaluation of the manufacture and the proper operation of the key elements of the crank press, in which after modernization, a quick tool assembly based on SMED (Single Minute Exchange of Die) was implemented. As a result of the introduced changes aiming at improving the forging aggregate and increasing the production efficiency, errors were observed on the manufactured products-forgings in the form of twists and joggles. In order to solve the problem, a lot of advanced methods was used, including: dynamic system of deformation analysis, numerical modeling and as well as dimensional and shape analysis by 3d scanning. Despite the above, this approach (classic way) did not solve the problem. A proprietary method with the use of 3D reverse scanning was proposed, which allows to solve the problem of forgings errors. Based on the measurement results and analyses for a few variants of production cycles, the necessary changes were obtained, making it possible to minimize the errors and obtain proper products in respect of geometry and quality. 相似文献
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9.
目的对中药石莼进行生药学研究,为其质量控制提供依据。方法对石莼基原、采收期、采收加工方法进行考证,建立性状、薄层色谱鉴别方法对其进行定性鉴别。结果明确了石莼药材基原、采收期及采收加工方法;所建立的薄层色谱鉴别方法化学成分信息量丰富,专属性强。结论本研究为中药石莼的鉴别、开发利用及质量标准的制订奠定了基础。 相似文献
10.
《Clinical oncology (Royal College of Radiologists (Great Britain))》2020,32(7):467-476
AimsMore efforts are required to minimise late radiation side-effects for paediatric patients. Pencil beam scanning proton beam therapy (PBS-PT) allows increased sparing of normal tissues while maintaining conformality, but is prone to dose degradation from interplay effects due to respiratory motion. We report our clinical experience of motion mitigation with volumetric rescanning (vRSC) and outcomes of children with neuroblastoma.Materials and methodsNineteen patients with high-risk (n = 16) and intermediate-risk (n = 3) neuroblastoma received PBS-PT. The median age at PBS-PT was 3.5 years (range 1.2–8.6) and the median PBS-PT dose was 21 Gy (relative biological effectiveness). Most children (89%) were treated under general anaesthesia. Seven patients (37%) underwent four-dimensional computed tomography for motion assessment and were treated with vRSC for motion mitigation.ResultsThe mean result of maximum organ motion was 2.7 mm (cranial–caudal), 1.2 mm (left–right), 1.0 mm (anterior–posterior). Four anaesthetised children (21%) showing <5 mm motion had four-dimensional dose calculations (4DDC) to guide the number of vRSC. The mean deterioration or improvement to the planning target volume covered by 95% of the prescribed dose compared with static three-dimensional plans were: 4DDC no vRSC, –0.6%; 2 vRSC, +0.3%; 4 vRSC, +0.3%; and 8 vRSC, +0.1%. With a median follow-up of 14.9 months (range 2.7–49.0) there were no local recurrences. The 2-year overall survival was 94% and distant progression-free survival was 76%. Acute grade 2–4 toxicity was 11%. During the limited follow-up time, no late toxicities were observed.ConclusionsThe early outcomes of mainly high-risk patients with neuroblastoma treated with PBS-PT were excellent. With a subset of our cohort undergoing PBS-PT with vRSC we have shown that it is logistically feasible and safe. The clinical relevance of vRSC is debatable in anaesthetised children with small pre-PBS-PT motion of <5 mm. 相似文献