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1.
Aim of the workTo evaluate hematologic parameters in patients with primary Sjögren's syndrome (PSS) and their association with disease activity.Patients and methodsSixty-five PSS patients and 65 age and sex matched control were studied. Neutrophil to lymphocyte ratio (NLR), mean platelet volume (MPV), red blood cells distribution width (RDW), platelet to lymphocyte ratio (PLR) and platelet count were evaluated. The erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) were measured. The European league against rheumatism (EULAR) Sjögren's syndrome disease activity index (ESSDAI) was assessed.ResultsThe mean age of patients was 47.8 ± 12.1 years and disease duration 5.71 ± 1.2 years and they were 63 females and 2 males. The mean ESSDAI was 6.4 ± 7.9 (3–25). 11 had neurological involvement. 92.3% of patients received low-dose prednisolone (<10 mg/day) and hydroxychloroquine (HCQ). The mean NLR (1.83 ± 0.8), PLR (131.9 ± 32.5) and MPV (8.82 ± 1.4) in patients was significantly higher than in control (NLR 1.57 ± 0.56, PLR 109.9 ± 24.7 and MPV 7.71 ± 1.3; p = 0.036, p < 0.001 and p < 0.001 respectively). The RDW tended to be higher in patients (13 ± 1.56) compared to control (12.83 ± 1.13) (p = 0.46). There was a significant correlation between ESSDAI with NLR (r = 0.29, p = 0.02), RDW (r = 0.37, p = 0.002), ESR (r = 0.32, p = 0.01) and CRP (r = 0.33, p = 0.007) and between MPV with CRP (r = 0.27, p = 0.03) and between RDW and ESR (r = 0.36, p = 0.003).On regression analysis, NLR and RDW were significant predictors of disease activity (p = 0.01 and p = 0.02 respectively).ConclusionThe MPV, PLR and NLR, were significantly increased in PSS. NLR and RDW can be used as indicators of disease activity.  相似文献   
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Background and aimsThe relation of serum cystatin C with new-onset cardiovascular disease (CVD) remains uncertain. We aimed to evaluate the prospective associations of serum cystatin C and its change with new-onset CVD in Chinese general population.Methods and resultsA total of 7064 participants free of CVD at baseline were enrolled from the China Health and Retirement Longitudinal Study. The change in serum cystatin C was calculated as cystatin C concentration at 2015 wave minus that at baseline (2011 wave). The primary outcome was new-onset CVD, defined as self-reported physician-diagnosed heart disease, stroke, or both during follow-up. The secondary outcomes were new-onset heart disease, and new-onset stroke. During a median follow-up duration of 7.0 years, a total of 1116 (15.8%) subjects developed new-onset CVD. Overall, after the adjustments for eGFR and other important covariates, there was a positive association between serum cystatin C and new-onset CVD (per SD mg/L increment; adjusted HR, 1.13; 95%CI: 1.08,1.18). When cystatin C was assessed as quintiles, the adjusted HRs for participants in the second, third, fourth and fifth quintiles were 1.15 (95%CI: 0.93, 1.41), 1.37 (95%CI: 1.11, 1.68), 1.47 (95%CI: 1.19, 1.81), and 2.03 (95%CI: 1.60, 2.56), respectively, compared with those in quintile 1 (P for trend<0.001). Furthermore, there was a positive association between the increase in cystatin C concentration and the subsequent new-onset CVD (per SD mg/L increment; adjusted HR, 1.14; 95%CI: 1.02,1.27).ConclusionBoth serum cystatin C and its increase were positively associated with new-onset CVD among Chinese general population.  相似文献   
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PurposeTo create a nonsurgical animal model of osteoarthritis (OA) to evaluate the effects of embolotherapy during geniculate artery embolization (GAE).Materials and MethodsFluoroscopy-guided injections of 700 mg of sodium monoiodoacetate were performed into the left stifle in 6 rams. Kinematic data were collected before and after induction. At 10 weeks after induction, Subjects 1 and 4–6 underwent magnetic resonance (MR) imaging with dynamic contrast enhancement (DCE) and Subjects 1, 3, and 4–6 underwent angiography with angiographic scoring to identify regions with greatest disease severity for superselective embolization (75–250-μm microspheres). Target vessel size was measured. At 24 weeks after angiography, DCE-MR imaging, angiography, and euthanasia were performed, and bilateral stifles were harvested. Medial/lateral tibial and femoral condylar, patellar, and synovial samples were cut, preserved, decalcified, and scored using the Osteoarthritis Research Society International criteria. The stifle and synovium Whole-Organ Magnetic Resonance Imaging Score and Multicenter Osteoarthritis Study score were determined. The volume transfer constant (Ktrans) and extracellular volume fraction (ve) were calculated from DCE-MR imaging along the lateral synovial regions of interest.ResultsThe mean gross and microscopic pathological scores were elevated at 38 and 61, respectively. Mean synovitis score was elevated at 9.2. Mean pre-embolization and postembolization angiographic scores were 5 and 3.8, respectively. Mean superior, transverse, and inferior geniculate artery diameters were 3.1 mm ± 1.21, 2.0 mm ± 0.50, and 1.6 mm ± 0.41 mm, respectively. Mean pre-embolization and postembolization cartilage and synovitis scores were elevated at 35.13 and 73.3 and 5.5 and 9.2, respectively. The Ktrans/ve values of Subjects 4, 5, and 6 were elevated at 0.049/0.38, 0.074/0.53, and 0.065/0.51, respectively. Altered gait of the hind limb was observed in all subjects after induction, with reduced joint mobility. No skin necrosis or osteonecrosis was observed.ConclusionsA nonsurgical ovine animal knee OA model was created, which allowed the collection of angiographic, histopathological, MR imaging, and kinematic data to study the effects of GAE.  相似文献   
5.
目的:探讨RT-Mind软件在鼻咽癌放疗临床靶区(CTV)、危及器官(OARs)自动勾画的可行性,为临床应用提供依据。方法:回顾性选取28例应用调强技术治疗的鼻咽癌患者,将放疗医师手动勾画CTV、OARs(脑干、脊髓、左右晶体、视交叉、左右视神经、左右腮腺、左右颞叶、左右颞颌关节、下颌骨)做为参考标准,再使用RT-Mind软件自动勾画CTV及OARs。对比手动与自动勾画在CTV和OARs区域的Dice相似性系数(DSC)、Jaccard系数(JAC)、敏感性指数(SI)、包容性系数(lncI)、质心偏差(DC)、Hausdorff距离(HD)等参数,从而评估自动勾画效果。结果:CTV的DSC、JAC、SI、lncl、DC、HD分别为:0.78±0.04、0.70±0.05、0.85±0.08、0.87±0.04、(7.76±5.03) mm、(12.3±1.16) mm,OARs中DC、HD值均在1 cm之内。结论:RT-Mind软件能够基本满足临床要求,能够较为准确地实现鼻咽癌患者CTV和OARs的自动勾画。由于病人既往病史的个体差异,放射治疗医师必须根据临床需要,对自动勾画的CTV和OARs进行修改后,才能用于治疗。若依据临床需求进一步完善自动勾画的个性化定制,相信RT-Mind软件在解剖结构复杂的鼻咽癌放疗中能够辅助放疗医生提高工作效率,更好地为患者服务。  相似文献   
6.
目的探讨Toll样受体?4(Toll like receptor?4,TLR?4)抑制剂TAK?242对大鼠重度牙周炎骨质吸收的影响,为重度牙周炎寻找辅助治疗手段提供实验基础。方法18只3周龄雄性Wistar大鼠随机分为3组(n=6),其中1组为正常对照组,另外2组以含有牙龈卟啉单胞菌(P.gingivalis)ATCC33277的5?0丝线结扎大鼠双侧上颌磨牙行重度牙周炎建模,分为牙周炎组、TAK?242组;TAK?242组从丝线结扎第1天起,通过尾静脉隔天注射1次溶于DMSO的TAK?242(2 mg/kg),另外两组注射相同体质量比例的DMSO溶剂,连续8周;第8周末处死3组大鼠,获取大鼠上颌骨标本,采用micro?CT扫描后三维重建,测量特定位点釉牙骨质界?牙槽嵴顶的距离评估骨丧失量,并对牙槽骨骨质相关参数和骨质微结构进行分析;组织学切片苏木精?伊(HE)染色观察牙周组织病理改变;甲基绿染色观察牙槽骨吸收情况;抗酒石酸酸性磷酸酶(TRAP)染色观察破骨细胞分布情况。结果Micro?CT定量分析显示:牙周炎组与TAK?242组牙槽骨吸收显著高于对照组;与牙周炎组相比,TAK?242组大鼠上颌第一磨牙近、远中根吸收位点的骨丧失均显著减轻(P<0.001),骨密度(P<0.05)与骨体积/总体积分数(P<0.01)显著增高,骨小梁数目与骨小梁厚度(P<0.01)相对增多,骨小梁分离度(P<0.01)和骨小梁结构模式指数显著降低。牙周炎组骨质呈现疏松多孔的蜂窝状结构,骨小梁结构恶化,向杆状结构转变;TAK?242组骨质微结构改善,骨量改善,骨小梁分布相对更致密,骨小梁结构与对照组更相似。HE染色发现牙周炎组与TAK?242组牙周附着丧失与牙槽骨吸收较对照组显著;与牙周炎组相比,甲基绿染色表明TAK?242组骨吸收减轻,TRAP染色显示破骨细胞浸润减少(P<0.001)。结论TLR?4抑制剂TAK?242能缓解大鼠重度牙周炎骨吸收,改善其多孔、稀疏、排列紊乱的炎症性骨小梁结构。  相似文献   
7.
In addition to recommendations for pharmacological treatment stratified for risk and phenotype, the new 2021 edition of the Spanish COPD Guidelines (GesEPOC 2021) proposes a personalized approach to treatable traits, defined as a characteristic (clinical, physiological, or biological) that can be identified by diagnostic tests or biomarkers, for which a specific treatment is available. Some treatable traits, such as malnutrition, sedentarism, emphysema or respiratory failure, can be treated with non-pharmacological therapies, and this was not covered in detail in the guidelines. This section of GesEPOC 2021 includes a narrative update with recommendations on dietary treatment, physical activity, respiratory rehabilitation, oxygen therapy, non-invasive ventilation, volume reduction, and lung transplantation. A PICO question with recommendations on the use of supplemental oxygen during exercise in COPD patients without severe hypoxemia is also included.  相似文献   
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9.
《Cancer radiothérapie》2022,26(8):1008-1015
PurposeDeep learning (DL) techniques are widely used in medical imaging and in particular for segmentation. Indeed, manual segmentation of organs at risk (OARs) is time-consuming and suffers from inter- and intra-observer segmentation variability. Image segmentation using DL has given very promising results. In this work, we present and compare the results of segmentation of OARs and a clinical target volume (CTV) in thoracic CT images using three DL models.Materials and methodsWe used CT images of 52 patients with breast cancer from a public dataset. Automatic segmentation of the lungs, the heart and a CTV was performed using three models based on the U-Net architecture. Three metrics were used to quantify and compare the segmentation results obtained with these models: the Dice similarity coefficient (DSC), the Jaccard coefficient (J) and the Hausdorff distance (HD).ResultsThe obtained values of DSC, J and HD were presented for each segmented organ and for the three models. Examples of automatic segmentation were presented and compared to the corresponding ground truth delineations. Our values were also compared to recent results obtained by other authors.ConclusionThe performance of three DL models was evaluated for the delineation of the lungs, the heart and a CTV. This study showed clearly that these 2D models based on the U-Net architecture can be used to delineate organs in CT images with a good performance compared to other models. Generally, the three models present similar performances. Using a dataset with more CT images, the three models should give better results.  相似文献   
10.
目的:探讨头颈部肿瘤患者在容积旋转调强放疗(volume modulated radiation therapy,VMAT)期间的解剖结构体积改变及剂量学变化。方法:选取8例头颈部鳞癌患者(口咽癌7例,喉癌1例),利用每日锥形束CT(CBCT)分析患者的靶区及腮腺体积随放疗时间的变化规律,并在放疗第10次和第22次再次进行定位CT扫描及计划设计,比较原计划与2次二程放疗计划中靶区、危及器官的剂量学变化。结果:所有患者的靶区及双侧腮腺体积随放疗的进行均呈缩小趋势,且双侧腮腺缩小较为明显。至放疗结束时,GTV和CTV体积退缩比率分别为 15.91%、11.58%;左右腮腺的退缩比率分别为29.72%、26.97%,P均<0.05。在2次二程放疗计划中靶区的D2、D98与脊髓、脑干的D1和原计划相比较差异均无统计学意义(P>0.05),但左右腮腺照射剂量与放疗前相比均有所减少,差异均有统计学意义(P<0.05)。结论:头颈部肿瘤患者在VMAT期间靶区和腮腺体积均会显著缩小,放疗中期有必要设计二程放疗计划。采用离线自适应性放疗技术可提高靶区照射的准确性并在一定程度上降低腮腺的受照剂量。  相似文献   
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