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1.
中药生产过程质量控制关键技术研究进展 总被引:10,自引:8,他引:2
中医药发展已上升到国家战略层面,在医药行业贯彻实施"中国制造2025"战略的新形势下,中药生产过程质量控制是中药工业需要加快突破的关键领域之一。对中药生产过程质量控制领域在工艺设计、分析检测、过程建模、制造装备等方面的关键共性问题进行解析,综述了中药生产过程质量控制体系中工艺过程理解、生产过程实时分析方法开发、过程控制策略建立3个方面的研究进展;并结合企业研究实践,介绍了质量源于设计(quality by design,Qb D)、过程分析技术(process analytical technology,PAT)、实验设计(design of experiment,DOE)、多变量统计分析等关键技术在上述3个研究方向中的应用进展,分析了实际工业应用的难点问题并对其应用前景进行展望,旨在为中药企业应用和提升生产过程质量控制技术提供参考。 相似文献
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《International journal of oral and maxillofacial surgery》2020,49(11):1445-1448
The advent of customized three-dimensional (3D) printing allows the affordable manufacturing of sophisticated medical devices, thereby providing swift and simple solutions to specific needs in modern healthcare. Meanwhile, certain devices such as industrial mandibular external fixators (EFs) have become less and less available from medical device companies because of decreased indications. What is more, their handling is often complex. The authors report, step by step, the original design and uneventful clinical use of a 3D-printed, customized mandibular EF. This device was designed together with a positioning and drilling guide for the fixation of a septic mandibular pseudarthrosis. It provided an adequate and satisfactory balance between lightness and rigidity. A simple, accurate and safe placement of the EF was achieved thanks to the skin-supported positioner and drilling guide, thereby making the procedure minimally invasive and time-efficient. To our knowledge, this is the first reported clinical use of a 3D-printed, customized mandibular EF to date. Because such 3D technology is becoming increasingly available to a large number of surgeons, the authors believe that the present innovation could become an alternative to reusable standard EFs. 相似文献
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面对来势汹汹的新型冠状病毒肺炎(COVID-19),如何能够正确、快速诊断和筛检出确诊病例显得尤为重要,国内诸多科技工作者都在积极开展相关的诊断试验研究。本文回顾了目前正在开展的十余项诊断试验的注册信息,针对其中存在的共性问题进行了讨论,重点阐述了如何使用PICOS原则构造COVID-19诊断试验的研究问题,还对金标准的设置、受试者的代表性、样本量计算和同步、独立、盲法的测定等诊断试验的设计要点进行了详细说明。旨在为广大研究者提供开展COVID-19诊断试验的设计建议,帮助研究者在顶层设计阶段减少、避免偏倚,完成高质量的临床研究,为临床诊疗提供循证医学证据。 相似文献
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If cigarette design was exogenous, inefficiencies arising from smoking could be addressed either with a tax per packet or with an ad valorem tax. However, it is well known that the consequences of these two instruments differ when product characteristics are endogenous. We consider three such characteristics: nicotine, tar, and flavor. Implementation of the first‐best social optimum typically requires the capacity to tax or regulate harmful ingredients. Without such a capacity, the next‐best policy often combines a per‐unit tax on cigarettes with an ad valorem subsidy. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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Laurie Lovett Novak Jonathan Wanderer David A. Owens Daniel Fabbri Julian Z. Genkins Thomas A. Lasko 《Applied clinical informatics》2021,12(1):164
Background The data visualization literature asserts that the details of the optimal data display must be tailored to the specific task, the background of the user, and the characteristics of the data. The general organizing principle of a concept-oriented display is known to be useful for many tasks and data types. Objectives In this project, we used general principles of data visualization and a co-design process to produce a clinical display tailored to a specific cognitive task, chosen from the anesthesia domain, but with clear generalizability to other clinical tasks. To support the work of the anesthesia-in-charge (AIC) our task was, for a given day, to depict the acuity level and complexity of each patient in the collection of those that will be operated on the following day. The AIC uses this information to optimally allocate anesthesia staff and providers across operating rooms. Methods We used a co-design process to collaborate with participants who work in the AIC role. We conducted two in-depth interviews with AICs and engaged them in subsequent input on iterative design solutions. Results Through a co-design process, we found (1) the need to carefully match the level of detail in the display to the level required by the clinical task, (2) the impedance caused by irrelevant information on the screen such as icons relevant only to other tasks, and (3) the desire for a specific but optional trajectory of increasingly detailed textual summaries. Conclusion This study reports a real-world clinical informatics development project that engaged users as co-designers. Our process led to the user-preferred design of a single binary flag to identify the subset of patients needing further investigation, and then a trajectory of increasingly detailed, text-based abstractions for each patient that can be displayed when more information is needed. 相似文献
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《Archives of physical medicine and rehabilitation》2022,103(8):1684-1692
Conducting high-quality clinical research is dependent on merging scientific rigor with the clinical environment. This is often a complex endeavor that may include numerous barriers and competing interests. Overcoming these challenges and successfully integrating clinical research programs into clinical practice settings serving rehabilitation outpatients is beneficial from both a logistical perspective (eg, supports efficient and successful research procedures) and the establishment of a truly patient-centered research approach. Leveraging our experience with navigating this research-clinical care relationship, this article (1) proposes the Patient-Centered Framework for Rehabilitation Research, a model for integrating patient-centered research in an outpatient clinical setting that incorporates a collaborative, team-based model encompassing patient-centered values, as well as strategies for recruitment and retention, with a focus on populations living with disabilities or chronic diseases; (2) describes application of this framework in a comprehensive specialty multiple sclerosis center with both general strategies and specific examples to guide adaptation and implementation in other settings; and (3) discusses the effect of the framework as a model in 1 center, as well as the need for additional investigation and adaptation for other populations. The 5 interconnected principles incorporated in the Framework and which prioritize patient-centeredness include identifying shared values, partnering with the clinical setting, engaging with the population, building relationships with individuals, and designing accessible procedures. The Patient-Centered Framework for Rehabilitation Research is a model presented as an adaptable roadmap to guide researchers in hopes of not only improving individual patients’ experiences but also the quality and relevance of rehabilitation research as a whole. Future investigation is needed to test the Framework in other settings. 相似文献
8.
Thomas Asendorf Robin Henderson Heinz Schmidli Tim Friede 《Statistics in medicine》2019,38(9):1503-1528
In some diseases, such as multiple sclerosis, lesion counts obtained from magnetic resonance imaging (MRI) are used as markers of disease progression. This leads to longitudinal, and typically overdispersed, count data outcomes in clinical trials. Models for such data invariably include a number of nuisance parameters, which can be difficult to specify at the planning stage, leading to considerable uncertainty in sample size specification. Consequently, blinded sample size re-estimation procedures are used, allowing for an adjustment of the sample size within an ongoing trial by estimating relevant nuisance parameters at an interim point, without compromising trial integrity. To date, the methods available for re-estimation have required an assumption that the mean count is time-constant within patients. We propose a new modeling approach that maintains the advantages of established procedures but allows for general underlying and treatment-specific time trends in the mean response. A simulation study is conducted to assess the effectiveness of blinded sample size re-estimation methods over fixed designs. Sample sizes attained through blinded sample size re-estimation procedures are shown to maintain the desired study power without inflating the Type I error rate and the procedure is demonstrated on MRI data from a recent study in multiple sclerosis. 相似文献
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《Journal of cranio-maxillo-facial surgery》2019,47(10):1551-1556
Fractures through the mandible at the level of the parasymphysis extending obliquely and traversing through the transitional zone to body region are relatively common. Therefore, a surgeon should have an appropriate understanding of the biomechanics of different plating techniques to fix these fractures. There is always a dilemma for the surgeon as to whether to fix these mandibular segments with one or two miniplates, and the presence of mental neurovascular bundle makes it more challenging. A study was planned in the Department of Oral and Maxillofacial Surgery to evaluate a novel twin-fork design of a miniplate used for fracture fixation at the transition zone of parasymphysis and body region of mandible after an in-vitro study of same design, and provided encouraging results. A total of 30 patients (10 patients in three groups each) were included in the study. All patients were evaluated preoperatively and postoperatively for operating time, ease of placement of miniplate, occlusion, reduction of fracture, neurosensory disturbances and infection. The novel design of twin-fork−shaped miniplate proved to be superior to the conventional miniplate in terms of neurosensory (Fisher exact test 17.40; p = 0.003) and functional outcome. There was statistically significant difference (χ2 = 13.895, p = 0.031) in postoperative reduction of fracture at week 4, indicating superiority of the twin-fork miniplate among the other conventional designs. The study concludes that the use of newly designed twin-fork−shaped miniplate should be encouraged in the fractures of transitional zone of parasymphysis-body region involving mental neurovascular bundle. 相似文献
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