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61.
羟甲基烟酰胺分散片的研制 总被引:2,自引:0,他引:2
目的:研制羟甲基烟酰胺分散片。方法:以崩解时间为指标。比较几种崩解剂的作用,以正交试验设计确立最佳处方,并与普通片进行体外溶出度比较。结果:崩解剂以低取代羟丙纤维素(L-HPC)效果最优,最佳处方崩解时间为78.9S,溶出速度远大于普通片。结论:所研制的羟甲基烟酰胺分散片溶出迅速。 相似文献
62.
Albert Kingman 《Journal of periodontal research》1992,27(4):378-389
Simulation studies were conducted to address specific statistical issues which arise in the design and analysis of gingivitis studies whose principal aim is the demonstration of superiority or equivalence of one product to another. The effects of measurement scale, using differences or ratios of group means, particular statistical test produces and specific rules demonstrating superiority or equivalence were investigated. An alternative concept to equivalence—denoted “least as good”—was also defined and evaluated. For a wide class of possible distributions of gingivitis scores, characterized by specific gamma distributions, the student-t test applied to means of subject GI gingivitis scores proved to be the most powerful of the test produces considered, having statistical properties quite similar to the randomization or permutation test procedure. Transformations of subject GI mean gingivitis scores did not produce an advantage in demonstrating either superiority or equivalence, and in some cases made it more difficult. Little difference was observed in test results when using the difference in group means as compared with using the ratio of group means for demonstrating either equivalence or superiority. The clinically significant rule produced the lowest false-positive rates for products slightly better than the active control, and similar false-positive and -negative rates as the statistically significant rule for products clearly superior to the active control. Demonstration of product equivalence will require more subjects per group than demonstrating product superiority, the size of this difference being a function of the definition of superiority that is accepted. Showing that the 90% confidence interval for 100*R is completely contained within the [90%, 110%] interval is the preferred method of demonstrating equivalence today, although much more research needs to be done to improve methods for demonstrating product equivalence. The “least as good” alternative to “equivalence” makes it easier to demonstrate “equivalence” for products slightly better than the active control product, but both experience great difficulty in demonstrating equivalence for lest products not quite as good as the active control. 相似文献
63.
64.
Polylactic acid (PLA) root replica in ridge maintenance after loss of a vertically fractured incisor
Abstract A periodontally affected tooth was prepared for a special treatment: Calcium hydroxide was introduced into the apical half of the root canal whereas its cervical part was filled with glass ionomer cement. The tooth was shortened subgingivally. After 6 weeks of epithelization over the residual root a palatal full-thickness flap was mobilized. The root was carefully extracted and chairside copy-milled from the biodegradable polylactic acid (PLA) material. The PLA-replica was implanted immediately into the socket and the flap was sutured. Aim of the treatment was to prevent the ridge collapse of the extraction area. Ridge height could be preserved during the 21 months of observation. With time the radiographic density of the cancellous bone increased in the implanted area, indicating that a PLA-replica is replaced by host's bone tissue. 相似文献
65.
STEVEN N. VASLEF LYLE F. MOCKROS KEITH E. COOK RONALD J. LEONARD JEFFREY C. SUNG ROBERT W. ANDERSON 《Artificial organs》1994,18(11):813-817
Abstract: A semiempirical mathematical model of convective oxygen transport is used to design a new, low pressure loss, implantable artificial lung that could be used as a bridge to lung transplantation in patients with advanced respiratory failure. The mass transfer and flow friction relations pertinent to the design of a cross–flow hollow fiber membrane lung are described. The artificial lung is designed to transfer over 200 ml/min of oxygen at blood flow rates up to 5 L/min. A compact design and a blood-side pressure loss of <15 mm Hg allows the device to be implanted in the left chest without the need for a prosthetic blood pump. Surgical implantation of the artificial lung would require the creation of inflow and outflow anastomoses. Oxygen would be supplied via an external source. Blood properties, operating conditions, and empirically determined mass transfer and flow properties are all specified and input into a computer program that numerically solves the design equations. Computer–generated values for the device frontal area, blood path length, and fiber surface area are thereby obtained. The use of this computer–assisted design minimizes the need for extensive trial–and–error testing of prototype devices. Results from in vitro tests of a prototype implantable lung indicate that the mathematical model we describe is an accurate and useful tool in the design of hollow fiber artificial lungs. 相似文献
66.
对50例神经根型颈椎病的CT征象进行了分析,并与X线平片加以比较。认为CT不仅在神经根型颈椎病的诊断中具有独特作用,而且在确定手术方法和手术途径的选择上也很有意义。作者认为在CT机还没有普及的情况下,摄一张良好的钩椎关节放大斜位片或椎间孔断层片对诊断神经根型颈椎病应是首选的。CT和X线平片相结合,综合分析,更有价值。 相似文献
67.
染色体图象处理系统具有7组67个功能,基本功能有视频处理、图象预处理、染色体配对和排序、图形功能、标注和批处理功能。把该系统应用于苯中毒工人遗传学生物标记研究、兰索拉唑对中国仓鼠肺细胞染色体畸变的影响研究、妇产科病人标本及猴外周血淋巴细胞标本的观察和分析的结果表明,该系统实用性强,并具有先进性、稳定性、灵活性和可拓展性等特点。 相似文献
68.
We describe how adverse drug reactions (ADRs) can play an important role in pharmaceutical research and drug development. Not only do ADRs represent the risks and drawbacks associated with drugs but they can also be related to other knowledge available in pharmaceutical and medical research. We offer a model that can be used to systematically map the pathways through which ADRs can lead to innovative research. These pathways include chemical, therapeutic or pathophysiological steps that can be taken to arrive at new knowledge based on ADRs. We used the development of angiotensin-converting enzyme inhibitors, especially captopril, as a case study. The similarity between the ADR profiles of captopril and penicillamine was a starting point for further innovation. Historical analysis shows that in several instances research in the field of angiotensin-converting enzyme inhibitors has been triggered by ADRs. The model presented here might be applicable to other areas of innovative drug research. 相似文献
69.
提出了文题所述的控制策略,依据输出分布曲线的特征变量选取方法和依据该项信息的规则控制系统。仿真研究得到了满意的结果。在一个实验性二元精馏塔上用IBM-PC进行试验亦获成功。本法对具有非线性特性的分布参数对象,较常规控制策略有明显的优越性。 相似文献
70.
Atle Dyregrov 《Journal of traumatic stress》1997,10(4):589-605
Critical Incident Stress Debriefings have become an intervention method used in various cultures, countries and groups following critical incidents. Although the structure of such meetings has been adequately described, utilization of the group processes involved has received less attention. A model, process debriefing (PD), based on experiences from Europe, is presented. Some differences between the current CISD process in the United States and the Europe based model are outlined. Various factors that impact the process of debriefings are discussed with a special emphasis on leadership, and implications of these group process variables for psychological debriefing are presented. It is emphasized that the continued exploration and discussion of process issues is critical to advance the understanding of the critical elements of debriefing. 相似文献