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991.
We present a case of 45-year-old female patient with the diagnosis of seropositive rheumatoid arthritis, who was admitted to our rheumatology department with exacerbation of the disease. The patient''s disease activity score (DAS 28) was 6.9. Physical examination revealed changes in the lung auscultation as a rough breathing sound at the middle and lower lobe of the right lung. Chest X-ray revealed multiple nodular densities in both lungs. Lung biopsy was performed for the diagnosis and revealed necrotizing granulomas with central fibrinoid necrosis surrounded by epithelioid cells. Such a histopathological picture is typical for rheumatoid nodules. Finally the patient was treated with rituximab, with significant improvement.  相似文献   
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994.
《Foot and Ankle Surgery》2014,20(2):120-124
BackgroundA few studies investigating the use of structural allograft in foot and ankle surgery are available. The purpose of this study is to analyze the clinical, functional and radiological results of patients treated with non-irradiated frozen structural bone allograft.MethodsWe analyzed 20 reconstructive surgeries of the hindfoot and midfoot performed between April 2004 and April 2010. The mean follow up period was 45.4 months. The results were evaluated according to AOFAS score, X-ray (allograft consolidation, alignment preservation, and allograft collapse or re-absorption), and complications.ResultsWe observed a 48-point mean improvement of AOFAS ankle and hindfoot score (17 cases), and a 53-point mean improvement of AOFAS midfoot score (3 cases). The mean bone consolidation time was 75 days. No graft fracture and no cases of non-union were seen.ConclusionThis treatment is a good option to treat severe defects or fill sequelae deformities.  相似文献   
995.
In this paper, I analyse issues related to the estimation of a common break in a large panel of time series data. Each series in the panel consists of a linear time trend and a random error. The linear time trend is subject to a break that occurs at the same date for all series. The error term is cross‐sectionally correlated through a factor structure. The break date is estimated jointly with the common factors. In particular, two break date estimators are analysed: the first is obtained as an iterative solution while the second is obtained as a global solution. The asymptotic properties of these estimators are analysed under both global and local asymptotic frameworks. These two estimators are shown to be asymptotically equivalent and to achieve a faster rate of convergence than the simple break date estimator that does not take common factors into account. The limiting distributions of the proposed break date estimators are provided so that asymptotically valid confidence intervals can be formed. Monte Carlo simulation results are provided to support the theoretical results.  相似文献   
996.
This paper examines the impact of Canada's war on drugs on segments of the Black community, specifically with respect to the impact of structural violence, over-policing, and high incarceration rates. It offers evidence of the systemic nature of these dynamics by examining the early context of the war, growing stigma against Blacks, globalizing influences, and the punitive focus of funding and policy. The paper also explores how Black men have been identified as the main enemy and how drug control efforts have served to diminish the health, well-being, and self-image of Black men via discriminatory and inequitable treatment before the law. The current high rates of imprisonment of Black men are an indicator of systematic deprivation of significant social capital, which will perpetuate socioeconomic harm and cycles of violence. This commentary calls for an immediate dissolution of policies regulating the war on drugs as the first step in remedying the injustices experienced by Black Canadians. Due to the lack of Canadian data in this important area, the paper also emphasizes the critical need for more research to shed more light on the Canadian-specific complexities.  相似文献   
997.
利用fNIRs研究噪声环境下脑力负荷变化规律   总被引:1,自引:0,他引:1  
目的研究噪声环境下操作者的脑力负荷(mental workload,MWL)变化规律。方法采用功能性近红外光谱技术(functional near-infrared spectroscopy,fNIRs)、心电、皮肤电和脉搏波多种生理测量手段结合脑力负荷敏感脑区的氧合血红蛋白幅值变化、主观量表评价和脑力负荷评估模型输出来评估噪声刺激下操作者的MWL变化。选用16名参试者完成中性图片N-back任务,分为噪声组和对照组,噪声环境采用(80±3)d B,对照组的外界声源控制为45 d B以下。结果在同一任务负荷状态下,噪声环境中参试者的脑力负荷水平高于对照组,其中噪声组2-back任务诱发的脑力负荷水平等同于对照组3-back任务诱发的脑力负荷水平,但其在3-back任务阶段脑力负荷仅略高于对照组的同等任务阶段。结论参试者在噪声环境下执行同等工作记忆任务时脑力负荷水平可以提高,但任务难度较高时提升幅度降低;利用fNIRs监测大脑前额叶皮层血氧生理参数方法能够有效评估噪声环境下的脑力负荷变化,值得进一步深入研究。  相似文献   
998.
Objective: This article in to study the association of structural abnormalities of the urinary tract in children with urinary tract infection (UTI) using ultrasound examination.Methods : 262 children with culture proven urinary tract infection were studied. Antibiotics were given as per sensitivity pattern. All children had an ultrasound of the abdomen done within 3 weeks. A micturating cystourethrogram (MCU) was done in those with abnormalities of the lower urinary tract detected on ultrasound, as well as in those who had recurrence of infection, after a normal ultrasound. IVU and renal isotope scans were done in selected cases.Result : All children were followed up until one year after the study period. Fifty-four patients had an underlying urinary tract anomaly; 42 were picked up by ultrasound and 12 by MCU. 22.9% of males and 15.9% of females had anomaly of the urinary tract. Children less than 2 years had the highest incidence of anomalies.Conclusion : Pelviureteric junction obstruction with hydronephrosis, vesicoureteric reflux and non-refluxing megaureter are the major anomalies picked up. 20% of children with urinary tract infections have an underlying structural abnormality of the urinary tract, three-fourth of which are picked up on ultrasound. An ultrasound abdomen is recommended in all children after the first UTI. In addition, an MCU is also indicated in all boys below 2 years with UTI, since one-third of anomalies will be missed if only ultrasound is done.  相似文献   
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1000.
凤仙透骨草的化学成分   总被引:2,自引:0,他引:2  
目的:研究凤仙花科凤仙花属植物凤仙花干燥茎中的化学成分.方法:利用硅胶,Sephadex LH-20及大孔吸附树脂等色谱法分离凤仙透骨草的化学成分,用波谱方法鉴定其结构.结果:从凤仙透骨草中分离并鉴定了7个化合物,分别鉴定为2-甲氧基-1,4-萘醌(1)、香草酸(2)、七叶内酯(3)、原儿茶酸(4)、芦丁(5)、大豆脑苷I(6)、1,2,4-三羟基萘-1,4-双-β-D-吡喃葡萄糖苷(7).结论:化合物2~7为首次从该属植物中得到.  相似文献   
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