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41.
An unsymmetrical diamine monomer 4‐(p‐aminophenoxy)‐3‐trifluoromethyl‐4′‐aminobiphenyl has been synthesized successfully. This monomer leads to the synthesis of different novel poly(ether imide)s when reacted with different dianhydrides like pyromellatic dianhydride (PMDA), benzophenone tetracarboxylic acid dianhydride (BTDA), 2,2‐bis(3,4‐dicarboxyphenyl) hexafluoropropane (6FDA), and oxy diphthalic anhydride (ODA). The poly(ether imide) prepared from this monomer on reaction with 6FDA is soluble in several organic solvents such as N‐methylpyrolidinone (NMP), dimethylformamide (DMF), N,N‐dimethylacetamide (DMAc), tetrahydrofuran (THF), and CHCl3. The poly(ether imide)s prepared from BTDA and ODA are soluble in NMP, DMF, and DMAc but not in THF or CHCl3, whereas the polymer prepared from PMDA is soluble only in NMP. The water uptake value for these poly(ether imide) films is very low (0.2–0.5%), and exhibited low dielectric constants (2.81 at 1 MHz). The polymers exhibited high thermal stability up to 532 °C in air for 5% weight loss, and high glass transition temperatures up to 288 °C. The polymer exhibited high tensile strength up to 135 MPa, modulus 3.2 GPa, and elongation at break up to 25%, depending on the exact polymer structure.

The structure of the poly(ether imide) synthesised from 4‐(p‐aminophenoxy)‐3‐trifluoromethyl‐4′‐aminobiphenyl and 2,2‐bis(3,4‐dicarboxyphenyl) hexafluoropropane. This polymer was soluble in many organic solvents.  相似文献   

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BackgroundDisability faced by a young person can impact the school-to-work transition and shape health and well-being over the life course. Unique barriers to entry and advancement within the labor market that are relevant to young people with disabilities underscore the need for tailored policy-level supports.ObjectivesTo examine and describe policies that support the school-to-work transition of young people with disabilities in Canada.MethodsA scan of policies which focused on the school-to-work transition of young people with disabilities across Canada was conducted between June 2019 and January 2020. Searches were completed within federal, provincial and territorial policy portals. Each policy relating to employment participation of people with disabilities was summarized. Policies that focused on the school-to-work-specific were synthesized using Bemelmans-Vidic, Rist and Vedung's policy tool framework.ResultsA total of 36 policies were identified by our scan that focused on the employment of people with disabilities. Only five policies explicitly addressed the school-to-work transition. All existing policies were implemented at the provincial level and aimed to promote entry into employment. The synthesis of policies revealed that financial policy tools were primarily used to incentivize employment, provision of workplace accommodations, or the development and implementation of job readiness programs.ConclusionOur analysis of federal, provincial and territorial policies in Canada uncovered a limited number of policies that specifically support the school-to-work transition. Addressing these policy gaps can increase the inclusion of young people with disabilities in the labor market.  相似文献   
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We aimed to report the implementation of a phenylketonuria (PKU) transition program and study the effects of follow-up with an adult team on metabolic control, adherence, and loss of follow-up. Fifty-five PKU patients were analysed in the study periods (SP): 2 years before (SP1) and after the beginning of adult care (SP2). Retrospective data on metabolic control and number of clinic appointments were collected for each SP, and protein intakes were analysed. In SP2, three patients (6%) were lost to follow-up. There was a small but statistically significant increase in median number of annual blood spots from SP1 to SP2: 11 (7–15) vs. 14 (7–20); p = 0.002. Mean ± SD of median blood Phe remained stable (525 ± 248 µmol/L vs. 552 ± 225 µmol/L; p = 0.100); median % of blood Phe < 480 µmol/L decreased (51 (4–96)% vs. 37 (5–85)%; p = 0.041) and median number of clinic appointments increased from SP1 to SP2: (5 (4–6) vs. 11 (8–13); p < 0.001). No significant differences were found regarding any parameter of protein intake. Our results suggest that the implementation of an adult service was successful as impact on metabolic control was limited and attendance remained high. Continuous dietetic care likely contributed to these results by keeping patients in follow-up and committed to treatment.  相似文献   
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The Eastern Mediterranean Region (EMR) is experiencing a nutrition transition, characterized by the emergence of overnutrition and micro-nutrient deficiencies. No previous study has comparatively examined nutrient intake in adults across countries in the EMR. This review examined the adequacy of nutrients in adults living in the EMR. Moreover, it analyzed the food balance sheets (FBS) for 1961–2018 to identify the trajectory of energy supply from macro-nutrients in the EMR. A systematic search was conducted from January 2012 to September 2020. Only observational studies were retained with a random sampling design. An assessment of the methodological quality was conducted. Levels of nutrient daily intake and their adequacy compared to the daily reference intake of the Institute of Medicine were reported across the region. No studies were identified for half of the region’s countries. Although nutrient energy intake was satisfactory overall, fat and carbohydrate intake were high. Intake of vitamin D, calcium, potassium, zinc, and magnesium were below that recommended. The analysis of the FBS data allowed for the identification of four linear patterns of trajectories, with countries in the EMR best fitting the ‘high-energy-supply from carbohydrate’ group. This systematic review warrants multi-sectorial commitment to optimize nutrient intake.  相似文献   
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The food environment in New Caledonia is undergoing a transition, with movement away from traditional diets towards processed and discretionary foods and beverages. This study aimed to develop an up-to-date food composition database that could be used to analyze food and nutritional intake data of New Caledonian children and adults. Development of this database occurred in three phases: Phase 1, updating and expanding the number of food items to represent current food supply; Phase 2, refining the database items and naming and assigning portion size images for food items; Phase 3, ensuring comprehensive nutrient values for all foods, including saturated fat and total sugar. The final New Caledonian database comprised a total of 972 food items, with 40 associated food categories and 25 nutrient values and 615 items with portion size images. To improve the searchability of the database, the names of 593 food items were shortened and synonyms or alternate spelling were included for 462 foods. Once integrated into a mobile app-based multiple-pass 24-h recall tool, named iRecall.24, this country-specific food composition database would support the assessment of food and nutritional intakes of families in New Caledonia, in a cross-sectional and longitudinal manner, and with translational opportunities for use across the wider Pacific region.  相似文献   
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ObjectivesRelocation to long-term care is a major challenge for older people. The View of Relocation Scale (VRS) was developed to address the need for a brief instrument to assess residents’ perceptions of the relocation.DesignSecondary analysis of data collected in a cluster randomized trial. The psychometric properties of the VRS examined in this study included factorial structure (using exploratory factor analysis), unidimensionality (Rasch modeling), internal consistency reliability (Kuder-Richardson Formula 20, squared multiple correlations, and item-total correlations), and known groups validity (analysis of variance). The results were used to identify the psychometrically most robust items for inclusion into the final version of the instrument.Setting and ParticipantsParticipants were 202 long-term care residents in Melbourne, Australia (mean age = 85.52 years, standard deviation = 7.33), who had relocated to the facility a mean of 4.4 weeks previously. Residents with moderately severe and severe dementia were excluded.MeasuresThe VRS was developed following a review of the literature describing residents’ views of relocation and was designed for administration shortly after their relocation.ResultsThere was support for a 2-factor, 10-item solution, with separate subscales assessing Perceived Control (degree of control in the decision making and planning for the relocation) and Perceived Need (perceived need for the relocation to long-term care). Participants who were admitted directly from hospital reported higher perceived need but lower perceived control than those admitted to the facility from home.Conclusion and ImplicationsThe VRS can be used to understand the impact of older people's perceptions of relocation to long-term care on their subsequent adjustment and well-being, and to identify those who may benefit from tailored support.  相似文献   
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BackgroundThe bioactive glass (BAG) is a promising solution for the reconstruction of bone defects and the eradication of infection in patients with osteomyelitis, however references to the treatment of diabetic foot osteomyelitis are scarce in the literature.MethodsOur experience in patients with diabetic foot osteomyelitis, who required surgical debridement and void filling, in which we use bioactive glass (n = 6), was evaluated. During a minimum follow-up of 24 months, the presence of persistent infection and healing rate, post-surgical complications, surgical reinterventions, degree of osseointegration and BAG-related side effects was analyzed.ResultsAt the end of the follow-up, none of the patients showed signs of persistent infection and the healing rate was 66.6% (4/6).Postoperative complications were noted in 3 patients and two of the them required new surgical intervention, both due to skin coverage or vascular complications.A complete osseointegration in the 66.6% of the patients and no cases of local adverse effects were recorded.ConclusionsThe bioactive glass can be a useful tool in the treatment of certain cases of diabetic foot osteomyelitis, provided that a multidisciplinary approach and strict patient selection is in place.Level of evidenceIV.  相似文献   
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王楠楠  李超宇  薛沁冰  陈刚  綦峥  于淼 《中草药》2023,54(11):3725-3733
非编码RNA(non-coding RNA,ncRNA)的失调与癌症的发生息息相关,并影响所有主要的癌症标志物。以ncRNA为切入点,根据中药药效物质基础及抗肿瘤机制,探究中药调控ncRNA诱导肿瘤细胞凋亡、抑制肿瘤细胞侵袭与迁移等作用机制,对于研发以ncRNA为基础的治疗药物具有重要意义。通过PubMed等数据库进行相关文献检索,对近5年有关中药调控ncRNA发挥抗肿瘤作用的研究进行综述,发现中药通过调节ncRNA,进而影响调节上皮间质转化、凋亡信号通路及耐药相关蛋白等多种途径,抑制肿瘤侵袭与迁移、促进肿瘤细胞凋亡和逆转肿瘤药物耐药的调控机制,为中药抗肿瘤药物相关研究提供参考。  相似文献   
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