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1.
Alexander E. J. Trevatt David R. Thomson Robert Miller Matthew Colquhoun Akinyemi I. Idowu Shakeel Rahman 《Journal of plastic surgery and hand surgery》2019,53(2):97-104
Academic output is just one aspect of a successful career as a plastic surgeon. However, for those with a strong interest in academia, the academic output of a department will likely be a key factor when deciding how to rank jobs. The aim of this study was to quantify and rank the academic output of plastic surgery units across the UK and Ireland. The Institute for Scientific Information (ISI) Web of Science Bibliometric analysis tool was used to collate cumulative (1950–2016), 10 year (2006–2016) and 3 years (2013–2015) research output data for plastic surgery units in the UK and Ireland. Sixty-six plastic surgery units were identified. Departments were ranked for each time period according to the number of papers produced, number of citations (Nc) and h-index (a measure of the impact of scientific output). The top 3 departments for number of papers in the last 10 years were The Royal Free Hospital, London (226) Broomfield Hospital, Chelmsford (218), and Morriston Hospital and Swansea (188). The top 3 for h-number were The Royal Free Hospital (21) Wythenshawe Hospital, Manchester (18) and Morriston Hospital (17). Academic output varies across plastic surgery units in the UK and Ireland. A number of departments have consistently maintained high academic outputs across the years and will be of interest to surgeons hoping to pursue a career in academia. 相似文献
2.
目的:探讨TomoTherapy QualityAssurance(TQA)数据趋势与螺旋断层放疗(Helical Tomotherapy,HT)系统输出的
联系。方法:回顾性分析了本院HT系统近3年内TQA各个模块的参数和数据趋势,探讨其与HT系统的静态输出剂量和
输出能量(D20/D10)变化的相关性。结果:楔形阶梯静态模块的z轴偏移参数与HT的静态输出剂量的相关性最强(r=0.883,
P<0.01)。基本剂量测定模块的出口检测器平整度值对能量变化最敏感(r=0.902),其次是楔形阶梯静态模块的能量差异
(r=0.897)和楔形阶梯螺旋模块的能量差异(r=0.852),灵敏度分别为2.3×10-4、3.1×10-4和5.7×10-4。结论:TQA有助于用户
追踪HT输出剂量和能量变化,及早进行必要的机器维护或剂量校准。 相似文献
3.
4.
Nirmanmoh Bhatia Buddhadeb Dawn Tariq S. Siddiqui Marcus F. Stoddard 《Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital》2015,42(1):16-24
Determining aortic stenosis (AS) severity is clinically important. Calculating aortic valve (AV) area by means of the continuity equation assumes a circular left ventricular outflow tract (LVOT). The full impact of this assumption in calculating AV area is unknown. Predictors of noncircular LVOT shape in patients with AS are undefined.In 109 adult patients with AS who underwent multiplanar transesophageal echocardiography, we calculated AV area by means of the standard continuity method and by a modified method involving planimetric LVOT area.We found 54 circular, 37 horizontal-oval, 8 vertical-oval, and 10 irregular LVOTs. Area derived by direct planimetry correlated better with the modified than the standard continuity method (r=0.89 vs r=0.85; both P=0.0001). Valve areas of patients with mild, moderate, or severe AS by planimetry were more often mischaracterized with use of the standard than modified method (29 vs 18; P <0.0001). Horizontal-oval AV area derived by planimetry (1.28 ± 0.55 cm2) was underestimated by the standard method (1.05 ± 0.47 cm2; P=0.001), but not by the modified method. Congenital AV morphology and low cardiac index were the only multivariate predictors of horizontal-oval shape. Low cardiac index was the only predictor of noncircular shape.More than half our patients with AS had noncircular LVOTs. Using the modified method reduces mischaracterizations of AS severity. Congenital AV morphology and low cardiac index predict horizontal-oval or noncircular shape. These data suggest the value of direct LVOT measurement to calculate AS severity in patients who have congenital AV or a low cardiac index. 相似文献
5.
《Clinical therapeutics》2019,41(5):836-847
PurposeA role for the immune system in causing myalgic encephalopathy/chronic fatigue syndrome (ME/CFS) is long suspected, but few studies have looked for specific autoantibodies that might contribute to the symptoms. Our aim was to look for evidence of antibodies to neuronal proteins in patients with ME/CSF.MethodsSera samples from 50 patients and 50 healthy individuals were sent coded to the Neuroimmunology Laboratory in Oxford. Screening for antibody binding to neuronal tissue was performed on brain tissue and neuronal cultures. Specific serum antibodies were assessed by antigen-specific cell-based assays and radioimmunoassays. After antibody testing, the associations between seropositive status and clinical data were investigated.FindingsOverall, 8 patients and 11 participants were found to have some serum immunoreactivity toward neuronal or neuromuscular junction proteins, but only 1 patient and 2 participants had specific serum antibodies. Nevertheless, seropositive status in patients with ME was associated with shorter duration since onset and a more severe disease.ImplicationsThe results indicate no overall increased frequency of antibodies to neuronal proteins in ME/CSF and no evidence of a specific antibody that might be causative or contribute to clinical features in patients. However, the association of seropositive status with shorter duration of disease and more severe symptoms suggests a possible role of antibodies at onset in some patients and should be the focus of future studies. 相似文献
6.
7.
王伏虎 《南京医科大学学报(英文版)》2002,16(2):49-64
Stroke is a debilitating disease that affects millions each year.While in many cases cerebral ischemic in jury can be limited by effectivw resuscitation or thrombolytic treatment,the injured neurons wither in a process known as delayed neuronal death(DND).Mounting evidence indicates that DND is not simply necrosis played out in slow motion but apoptosis is triggered.Of particular interest are two groups of signal proteins that participate in apoptosis-cyclin dependent kinases(CDKs) and p53-among a myriad of signaling events after an ischemic insult.Recent investigations have shown that CDKs,a family of enzymes initially known for their role in cell cycle regulation,are activated in injured neurons in DND.As for p53,new reports suggest that its up-regulation may represent a failed attempt to rescue in jured neurons,although its up-regulation was previously considered an indication of apoptosis.These observations thus rekindle an old quest to identify new neuroprotective targets to minimize the stroke damage.In this review,the author will examine the evidence that indicates the participation of CDKs and p53 in DND and then introduce pre-clinical data to explore CDK inhibition as a potential neuroprotective target.Finally,using CDK inhibition as an example,this paper will discuss the pertinent criteria for a viable neuroprotective strategy for ischemic in jury. 相似文献
8.
J. Epelbaum L. Tapia Arancibia J.P. Herman C. Kordon M. Palkovits 《Brain research》1981,230(1-2):412-416
Somatostatin (SRIF) in the central nervous system is mostly concentrated in the median eminence (ME). Immunocytochemical methods have revealed high densities of SRIF-positive perikarya between the preoptic area and the periventricular nucleus of the hypothalamus (NPE). The aim of the present study was to define more precisely the specific pathways of SRIF neurons from NPE to the ME. SRIF levels were measured by radioimmunoassay, following various hypothalamic transections. Frontal periventricular sections decreased SRIF-ME content by 70% (P less than 0.01), when located at the anterior end of the ME but no diminution was observed when the cuts were located anteriorly or posteriorly. Parasaggital transections decreased SRIF-ME levels by 50% (P less than 0.05) when located at the outer border of the ventromedial and premammillary nucleus, but the decrease was not significant when cuts were located anteriorly. Taken together, our data indicate that most SRIF-containing neurons, originating in the NPE, do not reach the ME directly along the border of the 3rd ventricle; instead they form a loop across the medial forebrain bundle before re-entering the mediobasal hypothalamus at the ME level. 相似文献
9.
T. L. Naneishvili M. G. Dashniani G. I. Machavariani 《Neuroscience and behavioral physiology》1987,17(1):49-55
Several types of neurons were differentiated on the basis of a study of neuronal activity in various parts of the cortex near the sulcus principalis during the execution of spatial delayed reactions by monkeys. It was established that the different types of neurons are represented in different numbers in. different parts of the cortex near the sulcus principalis. The determination of several factors influencing the activity of these neurons and the comparison of data on their quantitative representation in the anterior, middle, and posterior parts of the cortex near the sulcus principalis with the existing behavioral data obtained after local ablations of identical regions of the brain made it possible to postulate that neurons belonging to the different types are involved in the analysis of different processes and represent different functional units.Translated from Fiziologicheskii. Zhurnal SSSR imeni I. M. Sechenova, Vol. 71, No. 12, pp. 1488–1494, December, 1985. 相似文献
10.
Steven Elia Peter Liu Carol Chrusciel Alan Hilgenberg Charrisios Skourtis Demetrios Lappas 《Journal canadien d'anesthésie》1989,36(1):2-8
Global coronary blood flow and metabolism were measured in seven patients on the first postoperative day following coronary
revascularization to test the hypothesis that tracheal extubation produces adverse haemodynamic responses akin to those observed
during tracheal intubation. Regional coronary flow and metabolic measurements were made in five of the seven patients. Extubation
from a continuous positive airway pressure (CPAP) of 5 cm H2O was associated with a statistically significant rise in cardiac index from 3.44 ± 0.23 L · min-1 · m-2 to 3.73 ± 0.15L·min-1 ·m-2 related to an increase in stroke index, without significant changes in heart rate, mean arterial and pulmonary capillary
wedge pressure. Consequently the changes in myocardial oxygen consumption (8.52 ± 0.55 to 8.85 ± 0.93 ml · min-1) and coronary blood flow (172 ± 18 to 179 ± 17 ml·min-1) were less prominent than those reported during intubation, where substantial rises in myocardial oxygen consumption and
coronary flow occurred. Two patients experienced cardiac lactate production but there were no changes in systemic or coronary
haemodynamics, nor were there clinical or electrocardiographic signs of ischaemia. We conclude that extubation does not appear
to be associated with adverse systemic or coronary haemodynamic responses in patients following coronary bypass grafting.
However, the revascularized myocardium may remain vulnerable to anaerobic metabolism in the immediate postoperative period.
Pour savoir si comme ľintubation, ľextubation de la trachée provoque des perturbations hémodynamiques, on a mesuré le métabolisme
et la circulation coronarienne globale chez sept patients, au lendemain ďun pontage aorto-coronarien. On a aussi calculé les
valeurs régionales de ces mêmes variables pour cinq ďentre eux. Ľindex cardiaque de 3.44 ± 0.23 L · min-1 · m-2 sous pression positive en respiration spontanée (CPAP) de 5 cm. H2O s’est élevé à 3.73 ± 0.15 L · min-1 · m-2 post-extubation avec une augmentation significative du volume ďéjection. La fréquence cardiaque et les pressions artérielles
moyennes et capillaires pulmonaires n’ont pas changé. Ainsi ľaugmentation de la consommation ďoxygène du myocarde de 8.52
± 0.55 à 8.85 ± 0.93 ml · min-1 et celle du flot coronarien de 172 ± 18 à 179 ± 17 ml · min-1 ont été moindres que celles, importantes, déjà observées lors de ľintubation. On a noté chez deux patients une production
de lactate par le myocarde, sans changement de ľhémodynamic systémique et coronarienne non plus que de signe clinique ou électrocardiographique
ďischémie. Donc, après un pontage coronarien, ľextubation ne semble pas causer ďeffet néfaste sur les circulations systémique
et coronarienne, toutefois, le myocarde revascularisé peut demeurer sensible au métabolisme anaérobique. 相似文献