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排序方式: 共有444条查询结果,搜索用时 17 毫秒
61.
Tetyana Pylypiv Shippee MS Markus Schafer MS Karis Pallone MA 《Gerontology & geriatrics education》2013,34(4):57-70
ABSTRACT There has been a substantial increase in the number of aging-related educational programs in the United States over the last two decades. Many of these programs utilize an experiential-learning approach, such as intergenerational service-learning, to train gerontology students to work effectively with older adults. This paper presents a model of training called the Bridge program, which is based in experiential learning and incorporates some of the broader goals of service-learning. Launched in 2003, the Bridge program involves graduate students residing in a retirement community for at least one academic year. The main goals of the program include: educating the students and the public about the aging process, recruiting future gerontologists, providing research opportunities for the Bridge students, and contributing to the retirement community. Evaluation of the program reveals several critical issues for successful implementation. 相似文献
62.
Deng X Xiong X Khomenko T Sandor Z Osapay K Tolstanova G Shiloach J Chen L Folkman J Szabo S 《Digestive diseases and sciences》2011,56(10):2792-2801
Background
Despite recent advances and better understanding of the etiology and the pathogenesis of gastrointestinal ulcer diseases, e.g., duodenal ulcer, the molecular events leading to ulcer development, delayed healing, and recurrence remain poorly elucidated. 相似文献63.
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65.
Tirouvanziam R Obukhanych TV Laval J Aronov PA Libove R Banerjee AG Parker KJ O'Hara R Herzenberg LA Herzenberg LA Hardan AY 《Journal of autism and developmental disorders》2012,42(5):827-836
The goal of this investigation was to examine plasma amino acid (AA) levels in children with Autism Spectrum Disorders (ASD, N?=?27) and neuro-typically developing controls (N?=?20). We observed reduced plasma levels of most polar neutral AA and leucine in children with ASD. This AA profile conferred significant post hoc power for discriminating children with ASD from healthy children. Furthermore, statistical correlations suggested the lack of a typical decrease of glutamate and aspartate with age, and a non-typical increase of isoleucine and lysine with age in the ASD group. Findings from this limited prospective study warrant further examination of plasma AA levels in larger cross-sectional and longitudinal cohorts to adequately assess for relationships with developmental and clinical features of ASD. 相似文献
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Irina Druzhkova Nadezhda Ignatova Natalia Prodanets Nikolay Kiselev Iliya Zhukov Marina Shirmanova Vladimir Zagainov Elena Zagaynova 《Clinical colorectal cancer》2019,18(1):e74-e86
Background
The conventional chemotherapy of colorectal cancer with irinotecan, 5-fluorouracil, and oxaliplatin remains one of the front-line treatments worldwide. However, its efficacy is quite low. Recently studies of the epithelial–mesenchymal transition (EMT) have become the focus of investigations into the cause of chemoresistance in several types of cancer, including colorectal cancer. The data about the role of EMT in chemosensitivity are controversial.Materials and Methods
Human colon adenocarcinoma cell lines HT29 and HCT116 and 14 primary short-term cultures established from patient tumors were used. The chemosensitivity to irinotecan, 5-fluorouracil, and oxaliplatin was assessed using the (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) test. Immunocytochemistry, immunohistochemistry, and Western blot test were used to investigate the E-cadherin expression, the loss of which is a major hallmark of EMT.Results
Elevated chemosensitivity of the cell line with EMT phenotype, HCT116, was demonstrated. Increased chemosensitivity was revealed in HT29 cell line upon EMT induction. E-cadherin–positive short-term cultures were more resistant to all the drugs tested, whereas each of E-cadherin–negative cultures showed sensitivity to at least one drug. The statistically significant dependency of cells viability on the E-cadherin expression (P < .04) was demonstrated on the short-term cultures using 2 concentrations of each drug.Conclusion
The data obtained may serve as a basis for the analysis of colon cancer chemosensitivity using short-term cultures and the assay of E-cadherin expression. 相似文献68.
Milena Ignatova Kalin Kalinov Reneta Toshkova Iliya Rashkov Marin Alexandrov 《Journal of biomaterials science. Polymer edition》2014,25(3):287-306
Nanofibrous poly(L-lactide-co-D,L-lactide) (coPLA) or coPLA/poly(ethylene glycol) implants loaded with plant polyphenolic compound gossypol (GOS) with anti-tumor activity were fabricated by electrospinning. Implants containing quaternized chitosan (QCh) were prepared by coating of the obtained fibrous materials with a thin film of cross-linked QCh. The morphology of the implants and chemical composition of the implant surface were studied by means of scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). In vitro cytotoxicity assay showed that GOS-loaded nanofibrous implants, both non-coated and QCh-coated displayed about two-fold higher inhibitory activity against Graffi tumor cells than that of free GOS at the 72nd h of incubation. As evidenced by the performed fluorescence microscopy analyses and SEM observations, the anti-tumor activity of the fibrous implants was mainly due to induction of apoptosis. The experiments in which the implants containing both QCh and GOS were placed locally into the tumor site after the tumor extirpation showed an increase in the survival rate and a lower rate of recurrence in the operative field and of metastases in regional lymph nodes. In this case, 40% of hamsters were alive on the 45th day of implantation and they did not show any clinical sign of recurrence in the operative field and metastases in the regional lymph nodes. 相似文献
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Rebecca Robillard Karianne Dion Marie‐Helene Pennestri Elizaveta Solomonova Elliott Lee Mysa Saad Anthony Murkar Roger Godbout Jodi D. Edwards Lena Quilty Alexander R. Daros Raj Bhatla Tetyana Kendzerska 《Journal of sleep research》2021,30(1):e13231
This study aimed to evaluate changes in sleep during the COVID‐19 outbreak, and used data‐driven approaches to identify distinct profiles of changes in sleep‐related behaviours. Demographic, behavioural and psychological factors associated with sleep changes were also investigated. An online population survey assessing sleep and mental health was distributed between 3 April and 24 June 2020. Retrospective questions were used to estimate temporal changes from before to during the outbreak. In 5,525 Canadian respondents (67.1% females, 16–95 years old: Mean ± SD = 55.6 ± 16.3 years), wake‐up times were significantly delayed relative to pre‐outbreak estimates (p < .001, = 0.04). Occurrences of clinically meaningful sleep difficulties significantly increased from 36.0% before the outbreak to 50.5% during the outbreak (all p < .001, g ≥ 0.27). Three subgroups with distinct profiles of changes in sleep behaviours were identified: “Reduced Time in Bed”, “Delayed Sleep” and “Extended Time in Bed”. The “Reduced Time in Bed” and “Delayed Sleep” subgroups had more adverse sleep outcomes and psychological changes during the outbreak. The emergence of new sleep difficulties was independently associated with female sex, chronic illnesses, being employed, family responsibilities, earlier wake‐up times, higher stress levels, as well as heavier alcohol use and television exposure. The heterogeneity of sleep changes in response to the pandemic highlights the need for tailored interventions to address sleep problems. 相似文献