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71.
目的:考察原料药粒径对头孢地尼颗粒体外溶出度的影响。方法参照2010版中国药典第二法,以 pH =6.8磷酸盐缓冲液为溶出介质,转速为50 r·min -1,采用紫外分光光度法为分析方法,考察不同粒径的原料制备的头孢地尼颗粒与参比制剂溶出的一致性。结果粒径为 D90:142.90μm、D50:30.25μm、D10:3.47μm(100目筛)和 D90:51.21μm、D50:10.71μm、D10:2.25μm(200目筛)的头孢地尼原料制成的颗粒溶出行为与原研不相似;在不同溶出介质中,D90:35.62μm、D50:6.98μm、D10:1.66μm 的头孢地尼原料制成的颗粒,与参比制剂的溶出行为均相似。结论建立的分析方法简单可靠,原料微粉化能够有效提高难溶性药物的溶出度。 相似文献
72.
Yukihiro Tsuchiya Fumitake Ishihara Goro Kajiyama Saburo Nakazawa Masao Otho Hiroshi Tanimura Yoshikazu Akura Minoru Harada Masabumi Hihara Yukio Kawai Yukihiro Kono Hajime Koshiyama Masahiro Morita Michiko Nakajima Kyoichiro Nishina Hiroshi Sagawa Terufumi Sakai Mitsuo Shoji Kayoko Sone Yoshihiro Sugimoto Keiichi Sugiyama Osamu Takahara Tomoo Takamura Susumu Tazuma Hideki Wakamatsu 《Journal of gastroenterology》1995,30(6):768-774
The use of bile acid dissolution therapy in extracorporeal shockwave lithotripsy of gallstones, remains controversial. Our
study examined whether chemolitholysis after sufficient disintegration enhanced stone clearance within 6 months of the first
lithotripsy. A total of 143 patients who developed one to three radiolucent stones measuring⪯30 mm in diameter were randomly
separated into two treatment groups: 47% were given lithotripsy alone, and 53% lithotripsy plus ursodeoxycholic acid (UDCA).
Repeated piezoelectric lithotripsy was given, with no limit on the total number of treatment sessions, to pulverize or disintegrate
stones into fragments<3 mm. Stones were disintegrated in 97% of all patients, and the fragments were ⪯2 mm in 50% of these
patients. According to an intention-to-treat analysis, 52% in the lithotripsy alone group and 58% in the UDCA group were free
of stones 6 months after the first lithotripsy (P=0.61). Of the patients with fragments⪯2 mm, 71% in the former and 86% in the latter group were free of stones 6 months after
the first lithotripsy, with no significant difference between the groups. Biliary pain occurred in 25% of all patients, including
3 with acute cholecystitis. We concluded that the sufficient disintegration of gallstones achieved with repeated lithotripsy
enhanced the early clearance of fragments, regardless of whether chemolitholysis was employed. 相似文献
73.
利用乙二胺活化纤维素,将活化后的纤维素(Ce)和热塑性聚氨酯(TPU)分别溶于氯化锂(LiCl)-N,N-二甲基乙酰胺(DMAC)体系,制得纤维素-热塑性聚氨酯(Ce-TPU)共混膜。利用傅里叶红外光谱仪(FT-IR)、扫描电子显微镜(SEM)、X射线衍射仪(XRD)、单纤强力仪、折痕恢复性测定仪对共混膜的结构和性能进行表征。结果表明:Ce和TPU相容性良好,w(TPU)=30%时为共混膜的最优配比,此时断裂强力较纯纤维素膜略有提高,断裂伸长率提高了68%,折皱回复角提高了17%,共混膜的抗皱性和弹性有所改善。 相似文献
74.
以软胶囊内容物中乙醇和1,2-丙二醇含量和环孢素A溶出率为指标,采用正交设计优化软胶囊囊材处方,通过稳定性考察结果优化制备工艺.结果表明,在囊材处方中加入高级多元醇,并在环境相对湿度25%、采用缓慢干燥工艺使胶皮水分在40 h内控制在8%,所制备的软胶囊较稳定.与市售环孢素A软胶囊相比,本品内容物中乙醇的迁移量减少,环孢素A的体外溶出行为相似.药动学研究表明,自制软胶囊与市售软胶囊在Beagle犬体内生物等效. 相似文献
75.
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77.
In this paper, effects of sodium phosphate (Na3PO4) and sodium nitrite (NaNO2) on the pitting corrosion of X70 carbon steel in 0.10 mol/L NaCl solution were investigated by potentiodynamic polarization technique, electrochemical impedance spectroscopy (EIS) method, scanning electron microscope (SEM) and scanning electrochemical microscope (SECM). The SECM equipment was used to observe the dynamic processes of the pitting corrosion in situ. Na3PO4 or NaNO2 in the sodium chloride solution decreased the local anodic dissolution and increased the pitting resistance of the specimen. By analysis and comparison, it can be concluded that the inhibition effect of Na3PO4 is mainly due to the formation of a salt film, while the corrosion inhibition of NaNO2 is principally attributed to a protective oxide film on the electrode surface. 相似文献
78.
《Journal of pharmaceutical sciences》2019,108(10):3157-3168
Literature data pertaining to the physicochemical, pharmaceutical, and pharmacokinetic properties of ondansetron hydrochloride dihydrate are reviewed to arrive at a decision on whether a marketing authorization of an immediate release (IR) solid oral dosage form can be approved based on a Biopharmaceutics Classification System (BCS)-based biowaiver. Ondansetron, a 5HT3 receptor antagonist, is used at doses ranging from 4 mg to 24 mg in the management of nausea and vomiting associated with chemotherapy, radiotherapy, and postoperative treatment. It is a weak base and thus exhibits pH-dependent solubility. However, it is able to meet the criteria of “high solubility” as well as “high permeability” and can therefore be classified as a BCS class I drug. Furthermore, ondansetron hydrochloride 8 mg IR tablets (Zofran® 8 mg) and multiples thereof (16 mg = Zofran® 8 mg × 2 tablets and 24 mg = Zofran® 8 mg × 3 tablets) meet the criteria of “rapidly dissolving” in dissolution testing. Ondansetron hydrochloride has a wide therapeutic window and is well-tolerated after oral administration. Based on its favorable physicochemical properties, pharmacokinetic data and the minimal risks associated with an incorrect bioequivalence decision, the BCS-based biowaiver procedure can be recommended for ondansetron hydrochloride dihydrate IR tablets. 相似文献
79.
Ilika Ghosh Amitava Mukherjee Anita Mukherjee 《Journal of applied toxicology : JAT》2019,39(12):1623-1639
The growing usage of nanoscale zerovalent iron particles (nZVI) in the remediation of soil, ground/surface water has elicited large‐scale environmental release triggering human exposure. The size of nanomaterials is a key regulator of toxicity. However, the effect of a variable size of nZVI on genotoxicity is unexplored in human cells. To the best of our knowledge, in this study, the cytotoxic, genotoxic and hemolytic potential of nZVI‐1 (15 nm) and nZVI‐2 (50 nm) at concentrations of 5, 10 and 20 μg/mL was evaluated for the first time in human lymphocytes and erythrocytes treated for 3 hours. In erythrocytes, spherocytosis and echinocytosis occurred upon exposure to nZVI‐1 and nZVI‐2, respectively, leading to hemolysis. Lymphocytes treated with 20 μg/mL nZVI‐2 and 10 μg/mL nZVI‐1, incurred maximum DNA damage, although nZVI‐2 induced higher cyto‐genotoxicity than nZVI‐1. This can be attributed to higher Fe ion dissolution and time/concentration‐dependent colloidal destabilization (lower zeta potential) of nZVI‐2. Although nZVI‐1 showed higher uptake, its lower genotoxicity can be due to lesser Fe content, Fe ion dissolution and superior colloidal stability (higher zeta potential) compared with nZVI‐2. Substantial accumulation of Ca2+, superoxide anions, hydroxyl radicals and H2O2 leading to mitochondrial impairment and altered antioxidant enzyme activity was noted at the same concentrations. Pre‐treatment with N‐acetyl‐cysteine modulated these parameters indicating the indirect action of reactive oxygen species in nZVI‐induced DNA damage. The morphology of diffused nuclei implied the possible onset of apoptotic cell death. These results validate the synergistic role of size, ion dissolution, colloidal stability and reactive oxygen species on cyto‐genotoxicity of nZVI and unlock further prospects in its environmental nano‐safety evaluation. 相似文献
80.
Khan Hashim Ali Muhammad Mohsin Ansari Fawad Ali Shah Fakhar Ud Din Muhammad Abdul Basit 《Journal of microencapsulation》2019,36(1):10-20
The study was aimed to prepare a co-amorphous system of valsartan (VAL) with vanillin (VAN) for improving its solubility and dissolution followed by its confinement in mesoporous silica particles (MSPs) to stabilise the co-amorphous system and prevent its recrystallization. Amorphous VAL and VAN were obtained through quench-cooling and VAL/VAN binary co-amorphous system (VAL/VAN-CAS) was prepared through solvent evaporation technique. The particle size and morphology of VAL/VAN-CAS-MSPs were studied using scanning electron microscopy (SEM) and solid-state characterisation was performed by differential scanning calorimetry (DSC) and X-ray powder diffraction (XRPD). The in vitro dissolution was investigated by dialysis bag diffusion method. SEM analysis revealed irregular shaped VAL/VAN-CAS-MSPs with a size range of 5–25?μm, while outcomes of DSC and XRPD confirmed the formation of VAL/VAN-CAS. The in vitro dissolution profiles demonstrated a significantly increased dissolution in first 60?minutes from VAL/VAN-CAS (~68%) and VAL/VAN-CAS-MSPs (~76%) compared to powder VAL (~25%). 相似文献