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961.
To enhance the dissolution of poorly soluble mefenamic acid, self-emulsifying formulation (SEF), composing of oil, surfactant and co-surfactant, was formulated. Among the oils and surfactants studied, Imwitor® 742, Tween® 60, Cremophore® EL and Transcutol® HP were selected as they showed maximal solubility to mefenamic acid. The ternary phase diagram was constructed to find optimal concentration that provided the highest drug loading. The droplet size after dispersion and drug dissolution of selected formulations were investigated. The results showed that the formulation containing Imwitor® 742, Tween® 60 and Transcutol® HP (10:30:60) can encapsulate high amount of mefenamic acid. The dissolution study demonstrated that, in the medium containing surfactant, nearly 100% of mefenamic acid were dissolved from SEF within 5 min while 80% of drugs were dissolved from the commercial product in 45 min. In phosphate buffer (without surfactant), 80% of drug were dissolved from the developed SEF within 5 min while only about 13% of drug were dissolved in 45 min, from the commercial product. The results suggested that the SEF can enhance the dissolution of poorly soluble drug and has a potential to enhance drug absorption and improve bioavailability of drug.  相似文献   
962.
Besides the design freedom offered by additive manufacturing, another asset lies within its potential to accelerate product development processes by rapid fabrication of functional prototypes. The premise to fully exploit this benefit for lightweight design is the accurate structural response prediction prior to part production. However, the peculiar material behavior, characterized by anisotropy, thickness dependency and scatter, still constitutes a major challenge. Hence, a modeling approach for finite element analysis that accounts for this inhomogeneous behavior is developed by example of laser-sintered short-fiber-reinforced polyamide 12. Orthotropic and thickness-dependent Young’s moduli and Poisson’s ratios were determined via quasi-static tensile tests. Thereof, material models were generated and implemented in a property mapping routine for finite element models. Additionally, a framework for stochastic finite element analysis was set up for the consideration of scatter in material properties. For validation, thin-walled parts on sub-component level were fabricated and tested in quasi-static three-point bending experiments. Elastic parameters showed considerable anisotropy, thickness dependency and scatter. A comparison of the predicted forces with experimentally evaluated reaction forces disclosed substantially improved accuracy when utilizing the novel inhomogeneous approach instead of conventional homogeneous approaches. Furthermore, the variability observed in the structural response of loaded parts could be reproduced by the stochastic simulations.  相似文献   
963.
964.

Introduction

Healthcare professionals must sufficiently understand ionising radiation and the associated protection measures to avoid unnecessarily exposing patients and staff to ionising radiation. Hence, a proper safety culture is important to lowering health risks. The development and establishment of an instrument that can indicate healthcare professionals' understanding/knowledge of radiation protection concepts can greatly contribute to a good safety culture.The purpose of the present study was to develop and psychometrically test the Healthcare Professional Knowledge of Radiation Protection (HPKRP) self-evaluation scale, which was designed to measure the knowledge level of radiation protection by healthcare professionals working with ionising radiation in a clinical environment.

Methods

The presented research employed a cross-sectional study design. Data were collected from eight Finnish hospitals in 2017. A total of 252 eligible nurses responded to the newly developed HPKRP scale. The face and content validity were tested with the Content Validity Index (CVI). Explorative factor analysis was used to test construct validity, whereas reliability was tested with Cronbach's alpha.

Results

Overall S-CVI for the HPKRP scale was 0.83. Exploratory factor analysis revealed a three-factor model for the HcPCRP scale containing 33 items. The first factor was defined by Radiation physics and principles of radiation usage, the second factor by Radiation protection, and the third factor by Guidelines of safe ionising radiation usage. These three factors explained 72% of the total variance. Cronbach's alpha coefficient for the scale ranged from 0.93 to 0.96.

Conclusion

The results provide strong evidence for the validity and reliability of the HPKRP scale. Additionally, educators can use the scale to evaluate healthcare students' understanding in radiation safety before and after education.  相似文献   
965.
Objective: To assess the relationship between the Screen for Cognitive Impairment in Psychiatry (SCIP) score and illness severity, subjective cognition and functioning in a cohort of major depressive disorder (MDD) patients.

Methods: Patients (n?=?40) diagnosed with MDD (DSM-IV-TR) completed the SCIP, a brief neuropsychological test, and a battery of self-administered questionnaires evaluating functioning (GAF, SDS, WHODAS 2.0, EDEC, PDQ-D5). Disease severity was evaluated with the Hamilton Depression Rating Scale (HDRS) and the Clinical Global Impression (CGI).

Results: Age and sex were associated with performance in the SCIP. The SCIP-Global index score was associated with disease severity (r?=??0.316, p?<?.05), the SDS, a patient self-assessment of daily functioning (r?=??0.368, p?<?.05), and the EDEC subscales of patient-reported cognitive deficits (r?=??0.388, p?<?.05) and their functional impacts (r?=??0.335, p?<?.05). Multivariate analysis adjusted for age and sex confirmed these tests are independent predictors of performance in the SCIP (CGI-S, F[3,34]?=?4.478, p?=?.009; SDS, F[3,34]?=?3.365, p?=?.030; EDEC-perceived cognitive deficits, F[3,34]?=?5.216, p?=?.005; EDEC-perceived impacts of functional impairment, F[3,34]?=?5.154, p?=?.005).

Conclusions: This study confirms that the SCIP can be used during routine clinical evaluation of MDD, and that cognitive deficits objectively assessed in the SCIP are associated with disease severity and self-reported cognitive dysfunction and impairment in daily life.  相似文献   

966.
967.
Background: Chronic hepatitis C virus (HCV) infection is common among people who inject drugs (PWID) and is associated with morbidity and premature death. Although HCV can be cured, treatment may be inaccessible. We studied HCV testing, status and treatment among marginalized people who use drugs in Ottawa, Canada, a setting with universal insurance coverage for physician services.

Methods: We analyzed data from the Participatory Research in Ottawa: Understanding Drugs study, a cross-sectional, peer-administered survey of people who use drugs from 2012 to 2013. We linked responses to population-based health administrative databases and used multivariable Poisson regression to identify factors independently associated with self-reported HCV testing, self-reported positive HCV status, and database-determined engagement in HCV treatment. Results: Among 663 participants, 562 (84.8%) reported testing for HCV and 258 (45.9%) reported HCV-positive status. In multivariable analysis, HCV-positive status was associated with female gender (RR 1.27; 95%CI 1.04 to 1.55), advancing age (RR 1.03/year; 95%CI 1.02 to 1.04), receiving disability payments (RR 1.42; 95%CI 1.06 to 1.91), injecting drugs (RR 5.11; 95%CI 2.64 to 9.91), ever injecting with a used needle (RR 1.30; 95%CI 1.12 to 1.52), and ever having taken methadone (RR 1.26; 95%CI 1.05 to 1.52). Of HCV positive participants, 196 (76%) were engaged in primary care but only 23 (8.9%) had received HCV therapy. Conclusions/Importance: Although HCV testing and positive status rates are high among PWID in our study, few have received HCV treatment. Innovative initiatives to increase access to HCV treatment for PWID are urgently needed.  相似文献   

968.
多黏菌素类抗菌药物是多重耐药鲍曼不动杆菌的最后防线,但随着临床对多黏菌素类药物使用增多,鲍曼不动杆菌对其耐药的报道也陆续出现,相关耐药机制的研究成为热点。本文对近年来国内外鲍曼不动杆菌对多黏菌素类耐药报道以及耐药机制研究进行综述,以期对临床合理应用多黏菌素类抗菌药物、保持其抗菌活性提供参考。  相似文献   
969.
970.
《The Journal of arthroplasty》2021,36(9):3067-3072
IntroductionSelf-reported penicillin allergies in patients undergoing total joint arthroplasty often results in the use of second-line prophylactic antibiotics. A higher risk of prosthetic joint infection (PJI) is associated with suboptimal antibiotics vs first generation cephalosporins, which have historically been grouped with other beta-lactam antibiotics such as penicillin for potential allergic reactions. This study evaluates the economic burden of self-reported penicillin allergies in total joint arthroplasty (TJA).MethodsData from studies reporting true incidence of IgE-mediated penicillin allergies, infection-free survivorship of TJA, and cost of PJI attributed to use of second-line antibiotics were obtained. Projected cost of preoperative penicillin allergy testing and potentially avoidable PJI associated with second-line antibiotic usage were calculated. This was compared with projected cost of PJI in the current state to estimate cost savings.ResultsImplementation of preoperative penicillin allergy testing leads to a potential savings of nearly $37 million to payors in the first year based on 1-year survivorship. This savings increases to $411.6 million over a 10-year span and $1.18 billion over a 20-year span.ConclusionPreoperative penicillin allergy testing or risk stratification via thorough history should be implemented as standard of care for patients with self-reported penicillin allergies before TJA and would result in decreased cost of PJI.  相似文献   
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