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Fibrocartilaginous Embolism (FCE) refers to the extrusion of some of the fibro-cartilaginous nucleus pulposus material from within the inter-vertebral disc to eventually embolize into one of the spinal cord vessels with resultant spinal cord infarction. According to a 2016 review, AbdelRazek et al. (2106) [1] there are 41 pathologically confirmed and 26 clinically suspected cases in the literature till the end of 2015. We add two more clinically diagnosed cases. 相似文献
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Inflammation involving the helper T cell 17 (Th17) subset of lymphocytes has been implicated in a number of diseases that affect the nervous system. As the canonical cytokine of Th17 cells, interleukin 17A (IL-17A) is thought to contribute to these neuroimmune interactions. The main receptor for IL-17A is expressed in many neural tissues. IL-17A has direct effects on neurons but can also impact neural function via signaling to satellite cells and immune cells. In the central nervous system, IL-17A has been associated with neuropathology in multiple sclerosis, epilepsy syndromes and ischemic brain injury. Effects of IL-17A at the level of dorsal root ganglia and the spinal cord may contribute to enhanced nociception during neuropathic and inflammatory pain. Finally, IL-17A plays a role in sympathetic axon growth and regeneration of damaged axons that innervate the cornea. Given the widespread effects of IL-17A on neural tissues, it will be important to determine whether selectively mitigating the damaging effects of this cytokine while augmenting its beneficial effects is a possible strategy to treat inflammatory damage to the nervous system. 相似文献
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《Radiography》2017,23(1):e14-e19
ObjectivesMammographic density (MD) is an independent risk factor for breast cancer and may have a future role for stratified screening. Automated software can estimate MD but the relationship between breast thickness reduction and MD is not fully understood. Our aim is to develop a deformable breast phantom to assess automated density software and the impact of breast thickness reduction on MD.MethodsSeveral different configurations of poly vinyl alcohol (PVAL) phantoms were created. Three methods were used to estimate their density. Raw image data of mammographic images were processed using Volpara to estimate volumetric breast density (VBD%); Hounsfield units (HU) were measured on CT images; and physical density (g/cm3) was calculated using a formula involving mass and volume. Phantom volume versus contact area and phantom volume versus phantom thickness was compared to values of real breasts.ResultsVolpara recognized all deformable phantoms as female breasts. However, reducing the phantom thickness caused a change in phantom density and the phantoms were not able to tolerate same level of compression and thickness reduction experienced by female breasts during mammography.ConclusionOur results are promising as all phantoms resulted in valid data for automated breast density measurement. Further work should be conducted on PVAL and other materials to produce deformable phantoms that mimic female breast structure and density with the ability of being compressed to the same level as female breasts.Advances in knowledgeWe are the first group to have produced deformable phantoms that are recognized as breasts by Volpara software. 相似文献
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《European journal of surgical oncology》2022,48(5):1110-1116
IntroductionLateral pelvic lymph node dissection (LPLND) is a technically challenging procedure and its learning curve has not been analysed against an oncologically relevant outcome. The purpose of the study was to determine the learning curve for LPLND in rectal cancers using nodal retrieval as performance measure.MethodsConsecutive LPLND for rectal adenocarcinomas from a single institution were retrospectively analysed. Cumulative sum (CUSUM) control charts were used to detect difference in performance with respect to lymph node yield. Negative binomial regression was used to determine factors influencing nodal harvest using Incidence Risk Ratios (IRR). Separate CUSUM curves were generated for open and minimally invasive surgeries (MIS).ResultsOne-hundred and twenty patients were included and all received preoperative radiation. MIS was used in 53.3%. Median lymph node yield was 6 with 20% nodal positivity. Increasing experience (IRR – 1.196) and MIS (IRR – 1.586) were the only factors that influenced nodal harvest. CUSUM charts revealed that learning curve was achieved after the 83rd case overall and after the 19 operations in MIS. There was a 20% increase in nodal yield after every 30 MIS LPLND performed.ConclusionsLearning curve for LPLND is relatively long and only increasing experience and minimally invasive operations increased nodal yield. 相似文献
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Rodger Kempsford Virginia Norris Sarah Siederer 《Pulmonary pharmacology & therapeutics》2013,26(2):256-264
Vilanterol (VI; GW642444M) is a novel inhaled long-acting β2-agonist with inherent 24 h activity in vitro in development as a combination with the inhaled corticosteroid fluticasone furoate for both COPD and asthma. These studies were conducted to determine the safety, tolerability, pharmacodynamics and pharmacokinetics of VI in healthy subjects and subjects with mild to moderate persistent asthma and moderate to severe COPD.Single doses of VI (25–100 μg) were given once daily to subjects with asthma and COPD and repeat doses once daily for 14 days to healthy subjects. Adverse events (AEs), vital signs, ECGs, pharmacodynamic endpoints, FEV1 and VI plasma pharmacokinetics (AUC, Cmax and Tmax) were determined following dosing.VI (25–100 μg) was well tolerated. The incidence and severity of AEs were comparable to placebo. Following VI administration there were no clinically significant abnormalities in vital signs, 12-lead ECG, Holter ECG, blood glucose or potassium. There were no statistically significant effects on QTc of single and repeat VI doses up to 50 μg; some differences were seen following the 100 μg VI dose after single and repeat dose in healthy subjects and single dose in asthmatic subjects. All VI doses produced increases in FEV1 from as early as 5 min after dosing which were maintained up to 24 h post-dose in subjects with asthma and COPD. In all subjects VI was rapidly absorbed (healthy subjects median Tmax at 5 min; asthma and COPD subjects median Tmax at 10 min) with systemic exposure increasing in an approximately dose proportional manner across the VI dose range. Marginal accumulation was seen on repeat dosing.Single doses of inhaled VI in subjects with asthma and COPD and repeat doses in healthy subjects were well tolerated with no clinically significant unwanted systemic effects. VI produced a rapid and prolonged bronchodilation over 24 h suggesting the potential for once daily administration. 相似文献
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目的探讨子宫内膜异位症(内异症)患者血清及腹腔液中6-异前列腺素F1α(6-k-PGF1α)的表达及其在内异症发病中的作用。方法选择2010年6月至2012年1月在我院妇科手术治疗并经病理证实为内异症的42例患者并进行分期,其中早期(Ⅰ期、Ⅱ期)20例,晚期(Ⅲ期、Ⅳ期)22例;并选择同期无月经改变、病理证实为正常子宫内膜的子宫肌瘤患者20例。所有患者均在术前采集上肢静脉血,术中采集腹腔液。采用酶联免疫吸附(ELISA)方法测定血液和腹腔液中6-k-PGF1α的水平,并对内异症患者血清和腹腔液中6-k-PGF1α的表达进行Pearson相关性分析。结果①内异症早期组、晚期组血清、腹腔液中6-k-PGF1α水平均比对照组明显增高(均P〈0.05);②内异症晚期组组血清、腹腔液中6-k-PGF1α水平均比内异症早期组明显增高(P〈0.05);③内异症组血清与腹腔液6-k-PGF1α水平之间呈明显正相关(r=0.580,P=0.008)。结论内异症患者血清及腹腔液中6-k-PGF1α水平明显增高,后者可作为评判内异症严重程度的参考指标。 相似文献
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