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排序方式: 共有3693条查询结果,搜索用时 0 毫秒
51.
Lisa Mosconi Juha O. Rinne Wai H. Tsui John Murray Yi Li Lidia Glodzik Pauline McHugh Schantel Williams Megan Cummings Elizabeth Pirraglia Stanley J. Goldsmith Shankar Vallabhajosula Noora Scheinin Tapio Viljanen Kjell Någren Mony J. de Leon 《Neurobiology of aging》2013
This study examines the relationship between fibrillar beta-amyloid (Aβ) deposition and reduced glucose metabolism, a proxy for neuronal dysfunction, in cognitively normal (NL) individuals with a parent affected by late-onset Alzheimer's disease (AD). Forty-seven 40–80-year-old NL received positron emission tomography (PET) with 11C-Pittsburgh compound B (PiB) and 18F-fluoro-2-deoxy-d-glucose (FDG). These included 19 NL with a maternal history (MH), 12 NL with a paternal history (PH), and 16 NL with negative family history of AD (NH). Automated regions of interest, statistical parametric mapping, voxel-wise intermodality correlations, and logistic regressions were used to examine cerebral-to-cerebellar PiB and FDG standardized uptake value ratios across groups. The MH group showed higher PiB retention and lower metabolism in AD regions compared with NH and PH, which were negatively correlated in posterior cingulate, frontal, and parieto-temporal regions (Pearson r ≤ −0.57, p ≤ 0.05). No correlations were observed in NH and PH. The combination of Aβ deposition and metabolism yielded accuracy ≥ 69% for MH vs. NH and ≥ 71% for MH vs. PH, with relative risk = 1.9–5.1 (p values < 0.005). NL individuals with AD-affected mothers show co-occurring Aβ increases and hypometabolism in AD-vulnerable regions, suggesting an increased risk for AD. 相似文献
52.
S. Chakraborti A. Mahadevan A. Govindan K. Sridhar N.V.S. Mohan I.R. Satish S. Rudrappa S. Mangshetty S.K. Shankar 《Pathology, research and practice》2013
Pituicytoma is a rare low-grade tumor (WHO Grade I) of pituicytes involving the sellar–suprasellar region, and originating from the specialized glial cells of the neurohypophysis. Clinically and radiologically, they closely mimic pituitary adenoma or meningioma. Diagnosis requires histopathological examination of the resected tissue. This uncommon glial neoplasm is a rarity, with only 57 cases reported in the literature so far. We report three cases of pituicytoma (aged between 7 and 24 years) presenting with reduced vision, headache and features of hypercortisolism in one case. Radiologically, these lesions mimicked meningioma, hypothalamic chiasmatic glioma and pituitary microadenoma, respectively. The second case is a 7-year-old girl, the youngest case on record. Since this tumor is uncommon, it is frequently misdiagnosed. Awareness of this entity is essential for planning management and treatment. We present a brief review of all cases reported in the medical literature, and describe the clinical symptomatology, associated endocrinological abnormalities, imaging characteristics, behavior and outcome. 相似文献
53.
54.
Anusua Dhara Md Saddam Hussain Shankar Prasad Kanaujia Manish Kumar 《Research in microbiology》2021,172(2):103797
Antibiotic acyldepsipeptide (ADEP) targets the bacterial ClpP serine protease and can inhibit the growth of numerous bacterial species by activating/dysregulating the protease activity within the cell. The spirochete Leptospira interrogans harbors two ClpP isoforms (LepClpP1 and LepClpP2). Supplementation of ADEP in the Leptospira growth medium resulted in the inhibition of bacterial growth. The ADEP mediated activation of the LepClpP mixture was dependent on the time allowed for the self-assembly of LepClpP1 and LepClpP2. The dynamic light scattering of the LepClpP mixture in the presence of the ADEP indicated a conformational transformation of the LepClpP machinery. Serine 98, a catalytic triad residue of the LepClpP1 in the LepClpP1P2 heterocomplex, was critical for the ADEP mediated activation. The computational prototype of the LepClpP1P2 structure suggested that the hydrophobic pockets wherein the ADEPs or the physiological chaperone ClpX predominantly dock are exclusively present in the LepClpP2 heptamer. Using the ADEP as a tool, this investigation provides an insight into the molecular function of the LepClpP1P2 in a coalition with its ATPase chaperone LepClpX. The shreds of the evidence illustrated in this investigation verify that ADEP1 possesses the ability to control the LepClpP system in an unconventional approach than the other organisms. 相似文献
55.
56.
Matthew Seager Shankar Kumar Emma Lim Graham Munneke Steve Bandula Miles Walkden 《The British journal of radiology》2021,94(1118)
Renal cryoablation is a treatment option for early stage renal cell carcinomas with excellent oncological outcomes and low morbidity. This review outlines the technique of renal cryoablation and provides a guide for interventional radiologists on setting up an integrated service within a renal cancer network multidisciplinary setting. Patient selection and preparation, together with the technical aspects which ensure optimal oncological outcomes and avoid collateral damage to adjacent organs are highlighted. 相似文献
57.
Khunsa Faiz Stephanos Finitsis Janice Linton Jai Jai Shiva Shankar 《Interventional neuroradiology》2021,27(2):291
BackgroundOrbital and peri-orbital venolymphatic malformations (VLM) are low flow vascular malformations. Intralesional bleomycin is now commonly being used to treat such malformations.ObjectiveThe purpose of this systematic review is to synthesize evidence on the safety and efficacy of bleomycin/pingyangmycin sclerotherapy for the treatment of orbital and peri-orbital VLM.MethodsWe searched Medline, Embase, Scopus and Cochrane database for studies reporting outcomes of bleomycin/pingyangmycin sclerotherapy for orbital and peri-orbital VLM between 1974 to April 5th, 2019. Nine retrospective cohort studies enrolling 132 patients were included. Two reviewers independently screened and extracted data and assessed the risk of bias. Predefined outcome measures were subjective and objective reduction of the lesion and associated complications.ResultsSubjective reduction of the lesions was seen in 96.2% of the studies. Objective reduction of the lesion and symptomatic improvement were reported in 91.6 and 95% of the studies respectively. Non responders were 9.0%. Minor adverse events were reported in 18.1% of the studies. Major complications like pulmonary toxicity or pulmonary fibrosis was not encountered in any of the included studies. Quality of evidence was generally low.ConclusionBleomycin/pingyangmycin sclerotherapy is very effective and relatively safe for the treatment of orbital and periorbital VLM and is not associated with any major side effects including pulmonary fibrosis.Limitations: The systematic review is limited mainly due to low quality of the included studies with retrospective design. 相似文献
58.
Niharika Saw Joshua C. Vacanti Xiaoxia Liu Monica SaRego Hugh Flanagan Bhavani Shankar Kodali 《Journal of investigative surgery》2015,28(2):95-102
Purpose: On time start of the first surgical case improves operating room (OR) utilization, physician, and patient satisfaction and decreases delays in subsequent cases. The goal of our study was to evaluate the effect of a multidisciplinary initiative to improve first patient in the room (FPIR) and first case on time start (FCOTS) metrics in a tertiary care setting. Materials and Methods: A multidisciplinary committee focused on first case start data collection. Reasons for both anesthesia and surgical delays were analyzed. Improvement efforts focused on the timely completion of surgical consent, a requirement of a surgical, anesthesia, and nurse team member presence at the patient's bedside by specific time, and parallel processing in the OR. Results: Over 65,100 OR cases were analyzed between 2007 and 2014. There was a statistically significant improvement in FPIR (82.80% versus 69.60%, p < .0001) and FCOTS (66.60% versus 55.90%, p < .0001). Surgical consent completion rate increased from 35% baseline to 68%–100%, depending on the surgical subspecialty. Improvements appeared sustainable several years following process implementation for both FPIR (84.60% versus 69.60%, p < .0001) and FCOTS (67.60% versus 55.90%, p < .0001). Conclusions: Our study demonstrates a successful targeted, multidisciplinary initiative to improve first case surgical starts in an academic setting. Our approach was organizational rather than punitive or rewarding on an individual basis. Strategies included establishing concrete, time-specific goals and posting them visibly, empowering individuals to fulfill them, and ensuring no compromise in patient safety. In the complex environment of academic medicine including research protocols and teaching in the ORs, our organizational approach proved sustainable over several years. 相似文献
59.
Ethnic variation in certain hematological and biochemical reference intervals in a south Indian healthy adult population 总被引:1,自引:0,他引:1
Sundaram M Mohanakrishnan J Murugavel KG Shankar EM Solomon S Srinivas CN Solomon SS Pulimi S Piwowar-Manning E Dawson S Livant E Kumarasamy N Balakrishnan P 《European Journal of Internal Medicine》2008,19(1):46-50
BACKGROUND: We established the biochemical and hematological reference intervals among a south Indian healthy adult population attending an HIV referral centre in Chennai, southern India. METHODS: In a cross sectional study, 213 study subjects (129 male and 84 female) were studied between March and August 2005. All of the parameters were analyzed using standard hematological and biochemical techniques. RESULTS: Certain biochemical (viz. total bilirubin, alanine transaminase, albumin, creatinine, total protein, lipid profile, creatine phosphokinase, uric acid and lactate) and hematological (mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration and lymphocyte levels) parameters presented higher upper limits. In addition, the upper limits of white blood cell count, platelet count, hematocrit, red blood cell count and hemoglobin level were low in comparison to the currently reported ranges. CONCLUSION: Ethnic variation in reference intervals was observed in certain biochemical and hematological analytes in a south Indian adult population. 相似文献
60.
Stephen Maloney Jacqueline Tunnecliff Prue Morgan Jamie E Gaida Lyn Clearihan Sivalal Sadasivan David Davies Shankar Ganesh Patitapaban Mohanty John Weiner John Reynolds Dragan Ilic 《Journal of medical Internet research》2015,17(10)
BackgroundApproximately 80% of research evidence relevant to clinical practice never reaches the clinicians delivering patient care. A key barrier for the translation of evidence into practice is the limited time and skills clinicians have to find and appraise emerging evidence. Social media may provide a bridge between health researchers and health service providers.ObjectiveThe aim of this study was to determine the efficacy of social media as an educational medium to effectively translate emerging research evidence into clinical practice.MethodsThe study used a mixed-methods approach. Evidence-based practice points were delivered via social media platforms. The primary outcomes of attitude, knowledge, and behavior change were assessed using a preintervention/postintervention evaluation, with qualitative data gathered to contextualize the findings.ResultsData were obtained from 317 clinicians from multiple health disciplines, predominantly from the United Kingdom, Australia, the United States, India, and Malaysia. The participants reported an overall improvement in attitudes toward social media for professional development (P<.001). The knowledge evaluation demonstrated a significant increase in knowledge after the training (P<.001). The majority of respondents (136/194, 70.1%) indicated that the education they had received via social media had changed the way they practice, or intended to practice. Similarly, a large proportion of respondents (135/193, 69.9%) indicated that the education they had received via social media had increased their use of research evidence within their clinical practice.ConclusionsSocial media may be an effective educational medium for improving knowledge of health professionals, fostering their use of research evidence, and changing their clinical behaviors by translating new research evidence into clinical practice. 相似文献