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91.
王聚乐  刘忠  周惠英  顿珠 《西藏大学学报》2007,22(3):115-117,124
制定藏药七味罗堆多吉颗粒剂的工艺方法:三因素三水平正交实验。结果:影响提取效果的因素顺序为:煎煮时间>加水倍数>浸泡时间,以煎煮时间影响最大。提取最佳工艺为A3B3C1,即浸泡1小时、加水量10倍、煎煮3小时。制粒工艺以辅料中可溶性淀粉30%,蔗糖41.7%所得颗粒各方面指标均良好。结论:提取工艺条件合理,稳定可行;制粒工艺符合颗粒剂的指标要求,切实可靠。  相似文献   
92.
不同水稻品种(系)的垩白差异及胚乳细胞学结构研究   总被引:1,自引:0,他引:1  
调查了18个水稻品种(系)的垩白度、垩白粒率和垩白大小,并对米粒胚乳横断面上的胚乳细胞和淀粉粒进行了电镜扫描.结果表明,供试品种(系)的垩白粒率和垩白度存在显著差异,但垩白大小差异不显著,不同品种(系)在稻米胚乳细胞的形态结构和排列方式上有所不同,其横断面上淀粉粒的分布情况也有明显差异.不同品种(系)的垩白米之间,品种内垩白米与非垩白米之间,以及垩白米不同部位之间的淀粉粒形态具有差异.米粒横断面背腹径方向上长方柱状细胞群(细胞长度为宽度的两倍以上)与垩白发生有一定相关性,但不是垩白发生的决定性因素.淀粉粒在米粒横断面上分布情况与垩白发生有着更为密切的关系,淀粉粒分布越均匀越不易发生垩白,而如果淀粉粒分布不均匀,则使得其排列疏松并最终产生垩白.本文还对垩白发生的机理进行了探讨.  相似文献   
93.
难治性血小板减少性紫癜中医治疗初探   总被引:2,自引:0,他引:2  
难治性血小板减少性紫癜(RITP)属于中医“血证”等范畴。我们通过多年临床观察发现,约70%的RITP患者具备“气阴两虚、血瘀内阻”证候,故确立“益气养阴活血法”为基本治疗原则,并以“益髓颗粒剂”为治疗药物,治疗41例RITP患者,显效2例,占4.88%;良效13例,占31.71%;进步22例,占53.66%;无效4例,占9.7%;总显效率与总有效率分别为36.59%与90.25%。  相似文献   
94.
骨髓增生异常综合征(MDS)以难治性全血细胞减少和易转化为急性白血病为特征。患者的预后、合并症和年龄是决定治疗策略时必须考虑的因素。治疗策略经常以支持治疗为主,包括造血细胞生成因子、输注红细胞和血小板以及抗感染治疗。另外诱导分化、免疫抑制治疗、刺激造血、靶向治疗、化疗、异基因骨髓移植等根据具体病情选择应用。我们明确提出“气阴两虚,血瘀内阻”的中医复合证候为MDS临床主证,以“益气养阴活血”为治疗大法,制成“益髓颗粒剂”,进行了大量实验及临床研究,获得了确切疗效。  相似文献   
95.
本文建立同时测定外感风痧颗粒中原儿茶酸、原儿茶醛、绿原酸、咖啡酸4种成分的HPLC方法。色谱柱为依利特Hypersil C18柱(250 mm×4.6 mm,5μm);流动相为乙腈-0.2%磷酸,梯度洗脱,流速1.0mL·min~(-1);柱温25℃。结果显示:4种指标成分分离效果良好,原儿茶酸在3.672~33.048μg·mL~(-1)、原儿茶醛在1.236~11.124μg·mL~(-1)、绿原酸在9.2~82.8μg·mL~(-1)、咖啡酸在1.488~13.392μg·mL~(-1)线性关系良好;平均加样回收率均为97.6%~103.3%。本方法准确、灵敏、可靠,重现性较好,可用于外感风痧颗粒的质量控制。  相似文献   
96.
Summary Granulation is a unit operation by which larger granules are produced from fine, powdery particles to improve appearance, flow properties and mixedness, reduce dustiness and, in general, produce engineered particles with superior attributes. Agglomeration in wet granulation is achieved by introducing a “binder” fluid onto a shearing mass of fine powders. This paper gives a general overview of the process with emphasis on a simplified granulation model based on a dimensionless parameter containing inertia and viscous dissipation energies between colliding particles: the so-celled Stokes number. The model incorporates most common features of all granulation devices (mixers) used in the pharmaceutical industry.Also described in the paper is a computer simulation that captures the movement of flowing powder in an ideal mixer-granu/ator with constant shear rate. A fraction of the total number of particles is wet (covered by binder and there-fore “sticky”) while the rest of the particles are dry. The numerical simulation depicts two distinct regimes of agglomeration found in a typical granulator: granule growth and subsequent breakup. During granule growth-simulations, final granule size and shape distributions are obtained by analyzing the size and shape of formed granules using a pattern-recognition technique. A second kind of simulation, also using rapid granular flow modeling, follows the rotation and deformation of an “agglomerate” held together by a liquid binder. Results from these simulations yield critical values of the Stokes number. Below the cdticel value, the agglomerates are stable and only rotate in response to shear while above the critical value they break into two or more pieces. At the critical value, they attain a steady elongated shape. Using values of the critical Stokes number, the model predicts the size of formed granules.The existence of the critical state in which granules attain a characteristic elongated shape is used to measure shear forces in a granulator by employing calibrated “test” particles of known strength. This knowledge is employed in granulation scale-up to determine a kinematic rule that conserves stresses in the small and the large-scale machines. It was found that conserving the magnitude of internal stresses in the moving powder yields granules with similar attributes in granulators of different size.  相似文献   
97.
韩雪  张黎  张永强  吴冀川  谭福利 《强激光与粒子束》2020,32(1):011018-1-011018-5
采用激光驱动技术模拟高速运动金属颗粒与气体相互作用过程,研究高速气固两相流输运过程。采用驱动靶优化设计、激光参数调节等方法对颗粒加速过程进行控制,利用高时空分辨率、高精度瞬态实验诊断技术获取高速颗粒瞬态物理图像。通过求解三维雷诺平均Navier-Stokes方程和刚体飞行六自由度动力学方程数值模拟高速单颗粒与气体混合过程,方程采用高斯−赛德尔隐式方法进行时间推进求解。研究表明,激光驱动方法能够有效地发射金属颗粒,阴影照相技术能够有效获取高速颗粒物理图像。数值模拟给出了高速颗粒与气体作用的流场参数。  相似文献   
98.
Materials released by secretory cells are stored inside intracellular membrane-bound vesicles. These moieties are not freely diffusible in the vesicle but remain immobilized in a Ca2+-crosslinked condensed-phase polyanionic polymer matrix. During exocytosis a Na+/Ca2+ ion exchange process triggers a volume phase transition resulting in massive swelling and release of the materials to the extracellular space. Here we formulate a simple model to assess Ca2+-ion binding from the swelling kinetics of polymer networks. We found the diffusivity of the networks (D) exhibits a power-law dependency on the Ca2+ concentration where D ∝ [Ca2+]−2/3. The model yields an estimate of charge density and ionic affinity of the polymer chains. Studies of post-exocytic swelling kinetics in airway mucin granules, mast cell granules and granules from the microalga (Phaeocystis globosa) were used to validate predictions from our model. These results suggest that independent of the cell type, from animal to plant cells, a single polyelectrolyte interaction mechanism appear to be responsible for product release in exocytosis.  相似文献   
99.
Silicon-phthalocyanine (SiPc) is chemically bonded to 3-aminopropltriethoxysilane (NH2(CH2)3Si(OC2H5)3, KH550) by the nucleophilic substituted reaction between the active chlorine of silicon dichlorine phthalocyanine (SiPcCl2) and amino-group of KH550. The reacted product is hybridized with 3-glycidoxypropltrimethoxysilane (CH2OCHCH2O(CH2)3Si(OCH3)3, KH560) with sol-gel processing to form sol-gel inorganic material with good physical-chemical and optical properties. Due to tethering SiPc to the network, the aggregation of SiPc is effectively prevented in sol-gel derived matrix, and the doping concentration of SiPc in the form of monomer in the matrix is greatly enhanced. The cross-linkage of SiPcCl2 and KH550 is estimated and confirmed with FT-IR spectra. The optical limiting effects (OLE) of the gel with different content of SiPc are investigated with a frequency double Q-switched Nd3+:YAG laser of 8 nsec. pulse.  相似文献   
100.
Starch is the primary form of reserve carbohydrate storage in plants. Rice (Oryza sativa L.) is a monocot whose reserve starch is organized into compounded structures within the amyloplast, rather than a simple starch grain (SG). The mechanism governing the assembly of the compound SG from polyhedral granules in apposition, however, remains unknown. To further characterize the proteome associated with these compounded structures, three distinct methods of starch granule preparation (dispersion, microsieve, and flotation) were performed. Phase separation of peptides (aqueous trypsin-shaving and isopropanol solubilization of residual peptides) isolated starch granule-associated proteins (SGAPs) from the distal proteome of the amyloplast and the proximal ‘amylome’ (the amyloplastic proteome), respectively. The term ‘distal proteome’ refers to SGAPs loosely tethered to the amyloplast, ones that can be rapidly proteolyzed, while proximal SGAPs are those found closer to the remnant amyloplast membrane fragments, perhaps embedded therein—ones that need isopropanol solvent to be removed from the mature organelle surface. These two rice starch-associated peptide samples were analyzed using nano-liquid chromatography–tandem mass spectrometry (Nano-HPLC-MS/MS). Known and novel proteins, as well as septum-like structure (SLS) proteins, in the mature rice SG were found. Data mining and gene ontology software were used to categorize these putative plastoskeletal components as a variety of structural elements, including actins, tubulins, tubulin-like proteins, and cementitious elements such as reticulata related-like (RER) proteins, tegument proteins, and lectins. Delineating the plastoskeletal proteome begins by understanding how each starch granule isolation procedure affects observed cytoplasmic and plastid proteins. The three methods described herein show how the technique used to isolate SGs differentially impacts the subsequent proteomic analysis and results obtained. It can thus be concluded that future investigations must make judicious decisions regarding the methodology used in extracting proteomic information from the compound starch granules being assessed, since different methods are shown to yield contrasting results herein. Data are available via ProteomeXchange with identifier PXD032314.  相似文献   
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