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71.
W/O/W型甘草酸单铵盐口服复乳的处方设计及其理化特性研究 总被引:2,自引:0,他引:2
采用均匀设计,以乳剂的稳定性参数为考察指标,考察了初乳乳化剂、复乳乳化剂、乳化时间等因素对复乳稳定性的影响;筛选出W/O/W型甘草酸单铵盐口服复乳的优化处方和工艺,并对复乳的主要理化特性和物理稳定性进行了考察。 相似文献
72.
A microcapsule form of nitrofurantoin was prepared by a simple coacervation method with carboxymethylcellulose and aluminium sulfate. 33 factorial design was performed for three independent variables, namely, the particle size of the drug, the size of the microcapsules and the pH of the dissolution medium. The dissolution tests with the formulated microcapsules were carried out according to the United States Pharmacopeia XXII rotating basket method at pH 1.2, 5 and 7.5, which represent the pH of gastrointestinal fluids. Release data were examined kinetically and the ideal kinetic models were estimated and t
63.2 values obtained from RRSBW distribution were used in the factorial design experiment. The influence of the independent variables on the dissolution of nitrofurantoin microcapsules could be expressed as the pH of the dissolution medium > particle size of the microcapsule > particle size of nitrofurantoin. The other aim of this study was to evaluate microcapsule formulation in terms of the United States Pharmacopeia criteria with a minimum of experiments. Our findings suggest that dosage forms which comply with the pharmacopoeia criteria for dissolution can be prepared and selected by factorial design. 相似文献
73.
Abstract. Objectives. To evaluate the efficacy of self-administered subcutaneous sumatriptan in the acute treatment of early-morning migraine attacks. Design. A double-blind, randomized, placebo-controlled, cross-over study. Setting. Thirteen neurology centres in France. Subjects. Patients of either sex, 18–65 years old, with two to six attacks of migraine (according to the International Headache Society (IHS) criteria, with or without aura) per month, of which at least two had to be early-morning migraine attacks. One-hundred-and-one patients were included, 96 being evaluable for the first attack and 81 for the cross-over design. Interventions. Two migraine attacks (grade 2/3) were treated with sumatriptan (6 mg) or placebo, with an optional second injection 1–24 h later. Main outcome measures. The primary end-point was headache relief: reduction in headache severity from grade 2/3 (moderate/severe) to grade 1/0 (mild/none) 2 h after treatment. Results. Sumatriptan was superior to placebo for headache relief (32 [78%] vs. 11 [28%] at the first attack; 29 [73%] vs. 8 [20%] at the second; P < 0.001). Because of a significant carry-over effect for some of the secondary end-points, a parallel-group analysis of the first attack was performed, which confirmed a significantly higher efficacy of sumatriptan for all end-points: pain-free rate (22 [46%] vs. 7 [15%]; P = 0.001) and use of a second injection (26 [53%] vs. 38 [81%]; P = 0.004). Sumatriptan was preferred by 74% of patients vs. 17% for placebo, and 9% expressed no preference (P < 0.0001). After complete relief, headache reappeared in 8/23 (35%) patients with sumatriptan and 3/7 (43%) with placebo. Adverse events were significantly more frequent with sumatriptan but they were minor and transient. Conclusion. Subcutaneous sumatriptan auto-injection is an effective and well-tolerated acute treatment of early-morning migraine attacks allowing earlier return to normal activity. 相似文献
74.
本文定义了一类“近乎双线性”系统。可用以近似一类奇异摄动双线性系统,而且可以描述某些实际工业对象。并发现其控制器的设计较方便。文中还给出了一种简单的反馈控制器的设计方法。又对一类多输入双线性系统,提出一种设计反馈控制器的改进方案,根据Lyapunov定理得到一非线性反馈控制律。以上设计方法分别对某合成氨反应器作了应用研究,仿真结果表明了方法的有效性。 相似文献
75.
76.
Ann Netten 《International journal of geriatric psychiatry》1989,4(3):143-153
A study of 13 homes for elderly people examining the effect of the environment on demented residents looked into the complexity of the design from the residents' point of view. Two principal tools were used in this investigation: ‘route diagrams’, which describe a resident's use of the home, and a measure devised to indicate each resident's ability to find her way around the home. These are described and the relationship between them explored. From this the following tentative conclusions are drawn:
- (i) The variables that influence a resident's ability to find her way around differ between group and communally designed homes.
- (ii) It would appear that group homes provide a more favourable design, especially in the case of physically frail demented elderly people.
- (iii) In group homes, the level of lighting is an important aid to a demented person in finding her way around.
- (iv) In communal homes, residents seem most able to find their way around homes that have been adapted from older premises.
- (v) In both types of home, ‘meaningful decision points’ can be seen as aids to a resident finding her way around.
77.
One hundred cases of recalcitrant glaucoma were operated with a long tube single-plate Molteno implant (LSMI). At the median follow-up of 15 months an intraocular pressure of 19 mm Hg was obtained in 64 of the 87 eyes (73%) which have a minimum follow-up of 6 months (secondary non-neovascular glaucomas=19; congenital glaucomas=26; secondary neovascular glaucomas=12). The interval probability (percentage±standard error) of obtaining a successful result (IOP19 mmHg) was 79% (±13) at twelve months from surgery, and 53% (±24) at the eighteen month interval. The least favorable results were obtained in the secondary non-neovascular glaucomas. Complications observed included choroidal detachment (24%), tube exposure (4%), tube-endothelium contact (6%), plus band keratopathy, fibrous ingrowth, traction retinal detachment and corneal ulcers.Seventeen cases needed repeate surgery for the management of complications. In order to decrease the post-operative hypotony, we have been using a tourniquet suture around the tube at the time of implantation to occlude it temporarily and limit the outflow. 相似文献
78.
Chien Yie W. Chien Te-yen Bagdon Robert E. Huang Yih C. Bierman Robert H. 《Pharmaceutical research》1989,6(12):1000-1010
Several transdermal contraceptive device (TCD) formulations were developed to provide a dual-controlled transdermal delivery of levonorgestrel (LN), a potent progestin, and 17-estradiol (E2), a natural estrogen. Using a sensitive HPLC method, the in vitro release and skin permeation profiles of LN and E2 from various TCD formulations were simultaneously characterized in the hydrodynamically well-calibrated Valia–Chien skin permeation cells and both were found to follow zero-order kinetics. The rates of drug release and skin permeation were observed to vary significantly depending upon some formulation parameters. Six-month stability studies were performed on seven formulations at room and elevated temperatures (37 and 45°C), and two (Formulations 4 and 5) were found to be acceptable, based on drug recovery, release rate, and skin permeation rate data. Judging from the 6-month accelerated stability studies, it is projected these two formulations will have shelf-life of at least 2 years. As a result of development of an efficient manufacturing process, Formulation 4 was selected for further evaluation. One-week primary skin irritation evaluation in 6 rabbits indicated that Formulation 4 is nonirritating, and it was thus selected for Phase I clinical bioavailability/dose proportionality studies in 12 healthy female volunteers of child-bearing age. Results of pharmacokinetic and pharmacodynamic analyses demonstrated that it is capable of achieving and maintaining a steady-state serum level of LN throughout the 3-week treatment period by weekly applications of one or two TCD patches (10 or 20 cm2). A dose proportionality was obtained in the serum drug levels, daily dose delivered, and contraception efficacy. An excellent correlation was obtained for the rates of transdermal delivery determined by the in vitro studies using human cadaver skin, the in vivo studies in rabbits, and the clinical studies in living subjects. 相似文献
79.
多孔碳酸化羟基磷灰石骨水泥的生物相容性研究 总被引:2,自引:0,他引:2
目的探讨一种新型的代骨材料--多孔碳酸化羟基磷灰石骨水泥的组织相容性.方法合成碳酸化羟基磷灰石骨水泥,添加成孔剂,制备能原位固化形成多孔结构的碳酸化羟基磷灰石代骨材料,并通过细胞毒性实验和肌内埋植实验检测其组织相容性.结果多孔碳酸化羟基磷灰石骨水泥的浸提液对骨髓基质细胞的生长无影响.细胞于材料表面的生长速度、形态与空白对照组无差别.肌内植入实验发现,材料周围纤维组织包膜的最大厚度为22.5μm,未发现炎性细胞反应.结论多孔碳酸化羟基磷灰石骨水泥具有良好的组织相容性,材料测试结果符合和标准. 相似文献
80.
植入式药物缓释系统在治疗骨科感染、肿瘤等方面具有良好的作用。随着组织工程学的进展,研制了不同的材料作为骨内植入式药物缓释系统的载体,拟对骨内植入式药物缓释系统载体材料研究现况及进展进行综述。 相似文献