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1.
Jennifer Novak Yujie Cui Paul Frankel Mina S. Sedrak Scott Glaser Richard Li Sabin Motwani Brian Kavanagh Arya Amini 《Practical radiation oncology》2021,11(3):e263-e266
PurposeTwitter is an increasingly popular social media platform within the health care community. The objective of this analysis is to characterize the profile of radiation oncology–related tweets and Twitter users over the past 6 years.Methods and MaterialsUsing the web-based social media analytics platform Symplur Signals, we filtered tweets containing at least 1 of the following hashtags or key words: #radonc, #radiationoncology, "rad onc," or "radiation oncology." We evaluated radiation oncology–related Twitter activity between October 2014 and March 2020 for tweet frequency, tweet content, and individuals or groups posting tweets. We identified the most influential Twitter users contributing to radiation oncology–related tweets.ResultsFrom 2014 to 2020, the quarterly volume of radiation oncology–related tweets increased from 5027 to 29,763. Physicians contributed the largest growth in tweet volume. Academic radiation oncologists comprise 60% of the most influential Twitter accounts responsible for radiation oncology–related content. The number of radiation-oncology resident physicians on Twitter increased from 25 to 328 over the past 6 years, and 20% of radiation-oncology residency programs have a Twitter account. Seventy-one percent of radiation oncology–related tweets generated direct communication via mentions, and 59% of tweets contain links to external sources, including scientific articles.ConclusionsThe number of physicians contributing radiation oncology–related Twitter content has increased significantly in recent years. Academic radiation oncologists are the primary influencers of radiation oncology–related Twitter activity. Twitter is used by radiation oncologists to both professionally network and discuss findings related to the field. There remains the opportunity for radiation oncologists to broaden their audience on Twitter to encompass a more diverse community, including patients. 相似文献
2.
A 68 year-old woman presented with a two-week history of amaurosis fugax, ipsilateral fronto-temporal headache and jaw claudication suggesting carotid giant cell arteritis. However, this syndrome proved to be due to atherosclerosis causing complete occlusion of the external carotid artery at its origin and narrowing of the internal carotid artery. Combined external and internal carotid endarterectomy relieved the symptoms. The symptom complex of temporal arteritis may be rarely mimicked by carotid atherosclerotic occlusive disease. 相似文献
3.
A K Burroughs L Marelli E Cholongitas P Manousou K Rolles V Karam V Delvart R Adam C Sabin 《Liver transplantation》2007,13(6):935-6; author reply 937
4.
Summary A simple technique of stereotactic craniotomy and intraoperative lesion localisation that uses the Brown-Robert-Wells (BRW) stereotactic frame is presented. The method optimises craniotomy placement and facilitates localisation of small intracerebral lesions. Using the system, 16 patients have had resection of intracranial neoplasms from deep and/or eloquent areas of the brain with no neurological morbidity. 相似文献
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Human C-reactive protein increases cerebral infarct size after middle cerebral artery occlusion in adult rats. 总被引:14,自引:0,他引:14
Ramanjit Gill John A Kemp Caroline Sabin Mark B Pepys 《Journal of cerebral blood flow and metabolism》2004,24(11):1214-1218
Human C-reactive protein (CRP), the classic acute phase plasma protein, increases in concentration after myocardial infarction and stroke. Human CRP binds to ligands exposed in damaged tissue and can then activate complement and its proinflammatory functions. In contrast, rat CRP, which binds to similar ligands, does not activate complement. In the present study, systemic complement depletion with cobra venom factor in adult rats subjected to middle cerebral artery occlusion did not affect cerebral infarct size, indicating that circulating complement does not contribute to injury in this model. However, we have previously reported that administration of human CRP to rats undergoing coronary artery ligation caused a marked increase in size of the resulting myocardial infarction, associated with codeposition of human CRP and rat complement in the infarcts. In the present study, we show that adult rats subjected to middle cerebral artery occlusion and then treated with human CRP similarly developed significantly larger cerebral infarcts compared with control subjects receiving human serum albumin. Human CRP can thus contribute to ischemic tissue damage in the brain as well as in the heart, and inhibition of CRP binding may therefore be a promising target for tissue protective acute therapeutic intervention in stroke as well as in myocardial infarction. 相似文献
7.
A. Mocroft M. A. Johnson C. A. Sabin M. Bofill G. Janossy A. N. Phillips 《Epidemiology and infection》1997,118(3):259-266
The relationship, in 539 individuals infected with the human immunodeficiency virus (HIV), between two prognostic markers, the CD4 count and beta-2-microglobulin (B2M), and the development of the acquired immunodeficiency syndrome (AIDS) and death was investigated. Cox proportional hazards models were used to determine the risk of AIDS or death. In a multivariate model which adjusted for demographic factors and treatment, the most recent measurements of B2M (relative hazard (RH) 1.37 per g/l higher) and CD4 count (RH 2.17 per log-unit lower) were both significantly associated with the development of AIDS. Similarly, in a multivariate model which additionally adjusted for the development of AIDS as a time dependent covariate, there was a strong relationship with risk of death for the most recent measurements of B2M (RH 1.34 per g/l higher), and CD4 lymphocyte count (RH 1.91 per log-unit lower). A difference in the level of B2M could be used among patients with similar CD4 counts as an indicator of increased risk of progression to AIDS or death. Using the most recent values of these markers provides a better estimate of the risk of AIDS or death, compared to the more common method of analysis, where baseline values of the markers are used. 相似文献
8.
Calciphylaxis – a topical overview 总被引:3,自引:0,他引:3
G Arseculeratne† AT Evans‡ SM Morley† 《Journal of the European Academy of Dermatology and Venereology》2006,20(5):493-502
'Calciphylaxis', a calcification syndrome associated with ischaemic cutaneous necrosis, is acquired naturally in humans in disease states. It is a life and limb-threatening complication, usually observed in patients with renal disease and secondary hyperparathyroidism, but known to occur in the absence of renal or parathyroid disease. The reported mortality rate, which ranges from 60-80%, relates to wound infection, sepsis and organ failure. It is a small-vessel vasculopathy, which is estimated to occur in about 4% of haemodialysis patients. Clinically, violaceous, reticulate areas of cutaneous necrosis and eschar may be evident, particularly in the extremities. In addition to the clinical picture, a raised calcium phosphorous product, an elevated parathyroid hormone level, radiographic evidence of vessel and soft-tissue calcification and the finding of mural calcification affecting small arteries and arterioles on histopathology help to confirm the diagnosis of this entity which generally has a poor prognosis. A high index of suspicion and an active multidisciplinary management approach, with rigorous attention to wound care and prevention of sepsis, are vital in the management of these patients. In this overview, we discuss the pathophysiology, clinical features and associations, risk factors, diagnosis and management issues relating to calciphylaxis. 相似文献
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10.
M. A. Sabin G. M. Blake S. M. MacLaughlin-Black I. Fogelman 《Calcified tissue international》1995,56(3):210-214
New developments in dual x-ray absorptiometry (DXA) allow the performance of high precision anteroposterior (AP) and lateral scans of spinal bone mineral density (BMD, units: g/cm2) without the patient moving from the supine position. Data from both projections may be combined to give an estimate of the true volumetric bone mineral density (VBMD, units: g/cm3) of the lumbar vertebral bodies. This report presents a cadaver study designed to validate DXA measurements of volumetric bone density. Sections of whole lumbar spine were scanned in AP and lateral projections in a water tank to simulate soft tissue. Individual vertebrae were then divided to separate the vertebral body from the neural arch, and vertebral body volume was measured using the displacement of sand. The bone mineral content (BMC) of vertebral bodies and neural arches was measured by ashing at 250°C for 60 hours followed by 500°C for a further 24 hours. The results showed that DXA scanning systematically underestimated ashing data by 14% for AP BMC, 33% for vertebral body BMC, 23% for vertebral body volume, and 12% for VBMD. Despite these significant systematic errors, the DXA measurements and ashing values were highly correlated (r=0.979-0.992). The results suggested that after allowing for the systematic errors, lateral DXA parameters related closely to true BMC, volume, and VBMD. 相似文献