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Background

Anterior tibial post impingement during gait and stair ambulation was reported in knees with posterior-stabilized prostheses. However, the link between anterior post impingement and knee kinematics and between anterior post impingement and the clinical outcome has not been well investigated. Therefore, the purpose of this study was to assess the anterior impingement to clarify the relevant kinematics and clinical results including patient-reported outcomes.

Methods

We analyzed 40 well-functioning knees in 20 patients with a posterior-stabilized prosthesis due to osteoarthritis and who were followed up for 2 years or more. Dynamic lateral radiographs during stair-climbing activity were analyzed using a shape-matching technique, and anterior post impingement and the clinical outcome were assessed.

Results

Anterior impingement of the tibial post was observed in 13 knees (33%) during the latter half of the stance phase and at the beginning of the swing phase with the average implant flexion angle of ?2.4°. Implant flexion was significantly smaller, while the femoral component was located more posterior in the impingement knees. The posterior tibial slope was significantly greater in the impingement group (6.7° ± 2.0°, 5.3° ± 1.9°, respectively; P = .041); however, no significant differences were demonstrated in anteroposterior laxity and patient-derived assessments.

Conclusion

To avoid anterior post impingement, the posterior tibial slope should be made at 5° or less. Femoral notch-anterior post articulation should be designed to have good congruency in order to act as an anterior stabilizer in the case of impingement at knee extension.  相似文献   
24.
目的:探讨翻转教学在高职《内科护理学》中与案例分析相结合的教学方法。方法:(1)调查研究 选取我校2014级高职高专两个大班(228人)的学生为研究对象,通过自制的问卷调查,了解《内科护理学》教学改革的必要性与改革方向,实施翻转教学的可行性和效果评价。(2)实验研究:实验组1大班(120人),对照组2大班(108人)。实验组选取《内科护理学》中循环系统疾病护理章节,进行翻转教学与案例分析相结合的教学方法,,对照组在同一章节仍用传统的教学方法。结果:(1)实验研究 实验组理论测试循环系统疾病得分值高于对照组,差异有统计学意义(p <0.05)。(2)调查研究 实验组护生认为翻转课堂与案例分析相结合的教学方法能促进知识的内化、提高课程的学习效果,培养自主学习的能力,缩短了理论实践与临床的距离。  相似文献   
25.
locStra is an ‐package for the analysis of regional and global population stratification in whole‐genome sequencing (WGS) studies, where regional stratification refers to the substructure defined by the loci in a particular region on the genome. Population substructure can be assessed based on the genetic covariance matrix, the genomic relationship matrix, and the unweighted/weighted genetic Jaccard similarity matrix. Using a sliding window approach, the regional similarity matrices are compared with the global ones, based on user‐defined window sizes and metrics, for example, the correlation between regional and global eigenvectors. An algorithm for the specification of the window size is provided. As the implementation fully exploits sparse matrix algebra and is written in C++, the analysis is highly efficient. Even on single cores, for realistic study sizes (several thousand subjects, several million rare variants per subject), the runtime for the genome‐wide computation of all regional similarity matrices does typically not exceed one hour, enabling an unprecedented investigation of regional stratification across the entire genome. The package is applied to three WGS studies, illustrating the varying patterns of regional substructure across the genome and its beneficial effects on association testing.  相似文献   
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Background

In 2016, the US Department of Agriculture (USDA)’s Supplemental Nutrition Assistance Program (SNAP) Retailer Rule proposed several changes for SNAP-authorized retailers, including: requiring retailers to have at least 85% of their food sales come from items that are not cooked or heated on site before or after purchase; requiring stores to stock seven varieties of qualifying foods from four staple food groups; requiring stores to carry perishable foods in three of the four staple groups; requiring stores to carry six units of qualifying foods at all times (depth of stock); disqualifying multiple ingredient foods and accessory foods from counting toward depth of stock requirements.

Objectives

To better understand arguments used to support or oppose the USDA’s proposed rule that all SNAP-authorized retailers carry more nutritious foods.

Design

We conducted a qualitative content analysis of a random sample of public comments posted to the US Federal Register (a publicly available database) in response to the USDA’s proposed rule.

Participants/setting

A random sample of 20% of all public comments submitted by individuals and organizations to the US Federal Register were analyzed (n=303) for this study.

Results

Three main themes were discussed: 1) arguments used in opposition to the rule; 2) arguments used in support of the rule; and 3) facilitators to assist stores in implementing the rule. Some of the subthemes included focusing on definitions used in the rule, reduced food access caused by stores leaving the SNAP program, lack of space and equipment for healthy foods, and the potential for increasing healthy food access.

Conclusions

Nutrition and dietetics practitioners may be tasked with working with stores to implement healthy changes. Nutrition and dietetics practitioners must understand the role that the USDA has in food policy. In addition, understanding how federal food policy influences the environments in which dietetics professionals’ clients are making food choices is important.  相似文献   
28.
Partition coefficients between human stratum corneum lipids and water (Ksclip/w) are collected or deduced from a variety of sources in a manner that approximately doubles the available data compared to the current state-of-the-art model (Hansen et al., Adv Drug Deliv Rev. 2013;65(2):251-264). An additional datum for water itself in porcine SC that considerably extends the molecular size and lipophilicity range of the data set is considered. The data are analyzed in terms of an extended linear free energy relationship involving octanol/water partition coefficients, Abraham solvation parameters, and a secondary, power law molecular weight dependence. The optimum fit to log Ksclip/w for the full data set reduces the standard error of prediction from 0.50 for a Hansen-like model to 0.39; corresponding multiplicative errors in Ksclip/w are reduced from a factor of 3.1 to one of 2.5. The difference in performance is driven by the water datum, which requires a more complex dependence on molecular size than that afforded by Abraham parameters. In the absence of the water value, the Hansen-like model, which does not include a dependence on molecular size, is essentially optimum. A comparison is presented to fluid-phase phospholipid–water systems, which have a demonstrably different structure–property relationship.  相似文献   
29.
A roadmap for the selection of a pharmaceutical salt form for a development candidate is presented. The free base of the candidate did not have sufficient chemical stability for development. The initially selected salt form turned out to be undevelopable because it was unstable during scale-up synthesis and storage. The rationale for the new solid form screening and the criteria for selection are discussed. Before the final selection, the pH solubility profiles of the 2 new salts, a benzoate and a besylate, were compared. Atypical solubility behavior was observed for the benzoate salt in hydrochloric acid with and without normal saline. A scheme is proposed illustrating how the pKas of the counterion and active pharmaceutical ingredient, the medium composition, and final pH affect the solubility and solution equilibria of the 2 selected salt forms. This scheme also includes the equilibria between solution and solid phases in different pH ranges. The pharmaceutical importance of this research is that it sheds light on how the acidity of the counterion can affect the solubility of the selected salt form in the gastric environment. With a well-designed formulation strategy, this property potentially can be translated to optimal biopharmaceutical performance of the drug product.  相似文献   
30.
The health effects of green tea are associated with catechins: (?)-epigallocatechin-3-O-gallate (EGCG), (?)-epigallocatechin, (?)-epicatechin-3-O-gallate, and (?)-epicatechin. An understanding of compound absorption, distribution, metabolism, excretion, and toxicity characteristics is essential for explaining its biological activities. Herein, absorption, distribution, metabolism, excretion, and toxicity properties of in vivo detected metabolites of green tea catechins (GTCs) have been analyzed in silico. The influence of metabolic transformations on absorption, distribution, metabolism, and excretion profiles of GTCs corresponds to the effects of size, charge, and lipophilicity, as already observed for other small molecules. Mutagenic, carcinogenic, or liver toxic effects were predicted only for a few metabolites. Similar to galloylated GTCs EGCG and (--)-epicatechin-3-O-gallate, the sulfo-conjugates were predicted to bind at the warfarin binding site. The low free plasma concentration of these derivatives may be consequential to their serum albumin binding. The activity cliff detected for methylated conjugates of EGCG indicates that GTCs' pro-oxidative activity in bound state comes primarily from free hydroxyl groups of the pyrogallol ring B.  相似文献   
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