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排序方式: 共有1343条查询结果,搜索用时 15 毫秒
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Başak Şahin Jeremy Fife Manoj B. Parmar Juliana Valencia-Serna Hilal Gul-Uludağ Xiaoyan Jiang Michael Weinfeld Afsaneh Lavasanifar Hasan Uludağ 《Biomaterials》2014
Cutaneous T-cell lymphomas (CTCLs) arise from specific molecular aberrations that lead to uncontrolled cell proliferation. RNA interference (RNAi) with short interfering RNAs (siRNAs) is a feasible approach to interrupt aberrant signal processing in CTCL cells, but functional biomaterial carriers are needed to effectively deliver siRNAs intracellularly. Towards this goal, we explored the utility of lipid-substituted polyethylenimines (PEI) carriers in a cell model of CTCL. Using caprylic and linoleic acid substituted 2 kDa PEI (PEI-CA and PEI-LA, respectively), we showed effective delivery of siRNA to T-lymphocyte Hut78 and Jurkat cells, but silencing of a model protein (Green Fluorescent Protein, GFP) was possible only in the Hut78 cells. To enhance siRNA delivery to Hut78 cells, a high siRNA: carrier ratio used to assemble the complexes and centrifugation of cells in the presence of complexes were found effective. The toxicities of PEI-CA and PEI-LA were significantly lower than other commercial carriers, 25 kDa PEI and Lipofectamine® RNAiMAX. This might have contributed to reduced siRNA delivery efficiency of the latter carriers. Screening several endogenous targets led us to identify phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K) and cyclin-dependent kinase 18 (CDK18) as viable targets to induce siRNA-mediated cell growth inhibition. The results of this study identified promising polymeric carriers and molecular targets that could control proliferation of CTCL cells based on RNAi therapy. 相似文献
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Wei Fang Dai Claire de Oliveira Scott Blommaert Reka E. Pataky David Tran Zeb Aurangzeb Cynthia Kendell Chris Folkins Chandy Somayaji Jeff Dowden Winson Cheung Erin Strumpf Jaclyn M. Beca Carol McClure Robin Urquhart James Ted McDonald Riaz Alvi Donna Turner Stuart Peacock Avram Denburg Rebecca E. Mercer Caroline Muoz Ambica Parmar Mina Tadrous Pam Takhar Kelvin K. W. Chan 《Current oncology (Toronto, Ont.)》2022,29(3):2046
Canadian provinces routinely collect patient-level data for administrative purposes. These real-world data (RWD) can be used to generate real-world evidence (RWE) to inform clinical care and healthcare policy. The CanREValue Collaboration is developing a framework for the use of RWE in cancer drug funding decisions. A Data Working Group (WG) was established to identify data assets across Canada for generating RWE of oncology drugs. The mapping exercise was conducted using an iterative scan with informant surveys and teleconference. Data experts from ten provinces convened for a total of three teleconferences and two in-person meetings from March 2018 to September 2019. Following each meeting, surveys were developed and shared with the data experts which focused on identifying databases and data elements, as well as a feasibility assessment of conducting RWE studies using existing data elements and resources. Survey responses were compiled into an interim data report, which was used for public stakeholder consultation. The feedback from the public consultation was used to update the interim data report. We found that databases required to conduct real-world studies are often held by multiple different data custodians. Ninety-seven databases were identified across Canada. Provinces held on average 9 distinct databases (range: 8–11). An Essential RWD Table was compiled that contains data elements that are necessary, at a minimal, to conduct an RWE study. An Expanded RWD Table that contains a more comprehensive list of potentially relevant data elements was also compiled and the availabilities of these data elements were mapped. While most provinces have data on patient demographics (e.g., age, sex) and cancer-related variables (e.g., morphology, topography), the availability and linkability of data on cancer treatment, clinical characteristics (e.g., morphology and topography), and drug costs vary among provinces. Based on current resources, data availability, and access processes, data experts in most provinces noted that more than 12 months would be required to complete an RWE study. The CanREValue Collaboration’s Data WG identified key data holdings, access considerations, as well as gaps in oncology treatment-specific data. This data catalogue can be used to facilitate future oncology-specific RWE analyses across Canada. 相似文献
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Gaurav Parmar Priti Soin Pranav Sharma Christy French Bing Han Puneet S. Kochar 《Radiology Case Reports》2022,17(1):223
Intervertebral disc herniation is common condition, with majority occurring in lumbar and cervical spine. Most lumbar disk herniations occur within the spinal canal, with approximately 7%-10% identified within the foramen or extraforaminal location. Extraforaminal disc herniation in extreme lateral, retroperitoneal or anterior terms are used when disc material is seen towards anterolateral or anterior to the spine. Disc herniation in these locations is easily mistaken for an abscess or a neoplasm especially when it is not connected to the parent disc (sequestered disc). We describe a case of 60-year male who initially was misdiagnosed as psoas abscess and subjected to invasive investigation which later turned out to be histologically confirmed disc sequestration in the retroperitoneum. Thus, knowledge of this condition is essential in avoiding unnecessary workup and treatment. 相似文献
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Magon Stefano Tsagkas Charidimos Gaetano Laura Patel Raihaan Naegelin Yvonne Amann Michael Parmar Katrin Papadopoulou Athina Wuerfel Jens Stippich Christoph Kappos Ludwig Chakravarty M. Mallar Sprenger Till 《Journal of neurology》2020,267(5):1536-1546
Journal of Neurology - Volume loss in the deep gray matter (DGM) has been reported in patients with multiple sclerosis (MS) already at early stages of the disease and is thought to progress... 相似文献
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Contrast-enhanced flair imaging in the evaluation of infectious leptomeningeal diseases 总被引:3,自引:0,他引:3
PURPOSE: The purpose of our study was to compare contrast-enhanced fluid-attenuated inversion recovery (FLAIR) images with contrast-enhanced T1 weighted images for infectious leptomeningitis. MATERIALS AND METHODS: We studied twenty-four patients with a clinical suspicion of infectious meningitis with unenhanced FLAIR, contrast-enhanced T1 weighted and contrast-enhanced FLAIR MR sequences. Twelve patients had cytologic and biochemical diagnosis of meningitis on cerebrospinal fluid (CSF) examination obtained 48 h before or after the MR study. Sequences were considered positive if abnormal signal was seen in the subarachnoid space (cistern or sulci) or along pial surface. RESULTS: Twenty-seven examinations in 24 patients were performed. Of the 12 patients (thirteen studies) in whom cytology was positive, unenhanced FLAIR images were positive in six cases (sensitivity 46%), contrast-enhanced FLAIR images were positive in 11 (sensitivity 85%), and contrast-enhanced T1 weighted MR images were positive in 11 patients (sensitivity 85%). Of the 12 patients (14 studies) in whom cerebrospinal fluid study was negative, unenhanced FLAIR images were negative in 13, contrast-enhanced FLAIR images were negative in 11, and contrast-enhanced T1 weighted MR images were negative in eight. Thus, the specificity of unenhanced FLAIR, contrast-enhanced FLAIR and contrast-enhanced T1 weighted images was 93, 79 and 57%, respectively. CONCLUSION: Our results suggest that post-contrast FLAIR images have similar sensitivity but a higher specificity compared to contrast-enhanced T1 weighted images for detection of leptomeningeal enhancement. It can be a useful adjunct to post-contrast T1 weighted images in evaluation of infectious leptomeningitis. 相似文献
50.
Milind M Porecha Dipak S Parmar Hiral R Chavda 《Journal of orthopaedic surgery and research》2011,6(1):3