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排序方式: 共有1582条查询结果,搜索用时 31 毫秒
41.
目的:研究不同干燥工艺对金钗石斛叶品质的影响,为改进该药材的初加工和扩大石斛药材的药用部位提供理论依据。方法:以金钗石斛叶为原材料,采用热风干燥、微波干燥、真空干燥和真空冷冻干燥4种不同干燥方式对金钗石斛叶进行干燥,探讨4种方式对金钗石斛叶色泽、微观结构、总多糖和石斛碱含量的影响。结果:真空冷冻干燥产品色泽保持最好,优于其他3种干燥方式。不同干燥方法对样品所呈现的微观结构有所区别。金钗石斛叶经真空冷冻干燥、真空干燥、热风干燥及微波干燥后总多糖质量分数分别为3.11%,3.02%,2.81%和2.74%。不同干燥工艺对金钗石斛叶总多糖含量的影响较大,而对石斛碱含量则影响很小。结论:从成本方面考虑,热风干燥方式下的金钗石斛叶色泽较好,有效成分含量较高,且所需设备简单、节能、处理量大,在企业加工中值得推广应用。 相似文献
42.
目的:探讨元胡止痛滴丸成型工艺及晾丸工艺的优化。方法:采用正交试验法,以滴丸的圆整度、丸重差异及成型率为考察指标,优化滴距、滴速、冷凝温度及料温等滴制工艺参数;应用低温真空干燥技术晾丸,并以滴丸含水量为考察指标,对干燥温度、压力和时间等晾丸工艺参数进行优化。结果:优选基质为PEG 6000,中药提取物与基质配比为1.0∶2.0;最佳滴制工艺:滴距为3 cm,滴速为45滴/min,冷凝温度为10℃,料温为85℃;最佳晾丸工艺:干燥温度为35℃,压力为-0.05 Mpa,时间为18 h。结论:该优化工艺合理、可行,极大提高了滴丸的生产效率,且重现性良好。 相似文献
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目的 进行榆柏烧烫伤喷雾剂与其功能主治有关的药效学研究.方法 采用小鼠扭体法和甩尾法分别观察榆柏烧烫伤喷雾剂的镇痛作用;运用二甲苯致小鼠耳廓肿胀模型、血管通透性试验分别评价榆柏烧烫伤喷雾剂的抗炎作用.建立Ⅱ度烫伤模型,记录小鼠背部皮肤结痂时间和创面愈合时间,并进行病理组织学观察.结果 榆柏烧烫伤喷雾剂高、中、低3个剂量组与对照组比较,均具有良好的镇痛作用和抗炎作用,能明显延长小鼠的痛反应潜伏期,显著降低毛细血管通透性,减少炎症渗出,减轻水肿;具有显著提高烫伤小鼠愈合率、缩短愈合时间、提高创面愈合率、促进创面愈合的作用,对烫伤小鼠病理组织学观察的3个方面均有不同程度的改善.结论 榆柏烧烫伤喷雾剂对烧烫伤皮肤有促愈合作用,且具有抗炎、镇痛作用. 相似文献
44.
目的 探讨卵巢高反应患者新鲜移植周期与冻融胚胎移植(frozen-thawed embryo transfer, FET)周期妊娠结局的差异,了解促排卵药物对新鲜周期子宫内膜容受性的影响。方法 回顾性分析2011年1月至2013年12月在中国医科大学附属盛京医院生殖中心促排卵周期行新鲜胚胎移植(582例)和全部胚胎冷冻再行FET(167例)周期的临床妊娠率、生化妊娠率、种植率、胚胎停育率、异位妊娠率、流产率、持续妊娠率和多胎妊娠率。结果 582例促排卵周期新鲜胚胎移植与167例FET周期比较临床妊娠率(42.44% vs. 69.46%),生化妊娠率(7.22% vs. 2.99%),种植率(28.27% vs. 48.99%),胚胎停育率(8.10% vs. 7.76%),异位妊娠率(5.26% vs. 4.31%),流产率(8.10% vs. 6.90%),持续妊娠率(34.19% vs. 59.88%),多胎率(35.22% vs. 37.93%)。组间比较临床妊娠率、生化妊娠率、种植率、持续妊娠率差异均有统计学意义(P<0.05)。结论 全胚冷冻再行冻融周期移植可显著提高卵巢高反应患者临床妊娠率、种植率及持续妊娠率,不增加多胎率的发生,可获得更为理想的妊娠结局。新鲜周期高雌激素可能对子宫内膜容受性有损害作用。 相似文献
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Chintan Vora Riddhish Patadia Karan Mittal Rajashree Mashru 《Scientia pharmaceutica》2016,84(2):393-408
This research focuses on the development of enteric microparticles of lansoprazole in a single step by employing the spray drying technique and studies the effects of variegated formulation/process variables on entrapment efficiency and in vitro gastric resistance. Preliminary trials were undertaken to optimize the type of Eudragit and its various levels. Further trials included the incorporation of plasticizer triethyl citrate and combinations of other polymers with Eudragit S 100. Finally, various process parameters were varied to investigate their effects on microparticle properties. The results revealed Eudragit S 100 as the paramount polymer giving the highest gastric resistance in comparison to Eudragit L 100-55 and L 100 due to its higher pH threshold and its polymeric backbone. Incorporation of plasticizer not only influenced entrapment efficiency, but diminished gastric resistance severely. On the contrary, polymeric combinations reduced entrapment efficiency for both sodium alginate and glyceryl behenate, but significantly influenced gastric resistance for only sodium alginate and not for glyceryl behenate. The optimized process parameters were comprised of an inlet temperature of 150°C, atomizing air pressure of 2 kg/cm2, feed solution concentration of 6% w/w, feed solution spray rate of 3 ml/min, and aspirator volume of 90%. The SEM analysis revealed smooth and spherical shape morphologies. The DSC and PXRD study divulged the amorphous nature of the drug. Regarding stability, the product was found to be stable under 3 months of accelerated and long-term stability conditions as per ICH Q1A(R2) guidelines. Thus, the technique offers a simple means to generate polymeric enteric microparticles that are ready to formulate and can be directly filled into hard gelatin capsules. 相似文献
48.
Tim Bergner Fabian Zech Maximilian Hirschenberger Steffen Stenger Konstantin M. J. Sparrer Frank Kirchhoff Clarissa Read 《Viruses》2022,14(12)
Infection with the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), the causative agent of the COVID-19 pandemic, leads to profound remodeling of cellular membranes, promoting viral replication and virion assembly. A full understanding of this drastic remodeling and the process of virion morphogenesis remains lacking. In this study, we applied room temperature transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) tomography to visualize the SARS-CoV-2 replication factory in Vero cells, and present our results in comparison with published cryo-EM studies. We obtained cryo-EM-like clarity of the ultrastructure by employing high-pressure freezing, freeze substitution (HPF-FS) and embedding, allowing room temperature visualization of double-membrane vesicles (DMVs) in a near-native state. In addition, our data illustrate the consecutive stages of virion morphogenesis and reveal that SARS-CoV-2 ribonucleoprotein assembly and membrane curvature occur simultaneously. Finally, we show the tethering of virions to the plasma membrane in 3D, and that accumulations of virus particles lacking spike protein in large vesicles are most likely not a result of defective virion assembly at their membrane. In conclusion, this study puts forward a room-temperature EM technique providing near-native ultrastructural information about SARS-CoV-2 replication, adding to our understanding of the interaction of this pandemic virus with its host cell. 相似文献
49.
Ajmal Zarinwall Viktor Maurer Jennifer Pierick Victor Marcus Oldhues Julian Cedric Porsiel Jan Henrik Finke Georg Garnweitner 《Drug delivery》2022,29(1):2086
Promising active pharmaceutical ingredients (APIs) often exhibit poor aqueous solubility and thus a low bioavailability that substantially limits their pharmaceutical application. Hence, efficient formulations are required for an effective translation into highly efficient drug products. One strategy is the preservation of an amorphous state of the API within a carrier matrix, which leads to enhanced dissolution. In this work, mesoporous silica aerogels (SA) were utilized as a carrier matrix for the amorphization of the poorly water-soluble model drug ibuprofen. Loading of tailored SA was performed post-synthetically and solvent-free, either by co-milling or via the melting method. Thorough analyses of these processes demonstrated the influence of macrostructural changes during the drying and grinding process on the microstructural properties of the SA. Furthermore, interfacial SA-drug interaction properties were selectively tuned by attaching terminal hydrophilic amino- or hydrophobic methyl groups to the surface of the gel. We demonstrate that not only the chemical surface properties of the SA, but also formulation-related parameters, such as the carrier-to-drug ratio, as well as process-related parameters, such as the drug loading method, decisively influence the ibuprofen adsorption efficiency. In addition, the drug-loaded SA formulations exhibited a remarkable physical stability over a period of 6 months. Furthermore, the release behavior is shown to change considerably with different surface properties of the SA matrix. Hence, the reported results demonstrate that utilizing specifically processed and modified SA offers a compelling technique for enhancement of the bioavailability of poorly-water soluble APIs and a versatile adjustment of their release profile. 相似文献
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