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991.
生物标志物是可被客观测量并能用于评价正常生物过程、病理过程及治疗反应的指标。生物标志物的发现是对其研究的第一步,其实质就是筛选出在不同的生物学状态或进程中的差异化物质。在这一阶段中,分析策略所考虑的重点是高通量化和定性(和/或半定量)性能。目前,生物标志物研究的热点已转移至蛋白质层面上。在蛋白质生物标志物的发现中,质谱以不同的策略和方式得到了广泛的应用,并仍在不断进步中。本文对蛋白质生物标志物的发现过程中常用的及新型的质谱应用策略进行了归纳阐述。  相似文献   
992.
Atypical mycobacterium infections often present as cervicofacial lymphadenitis in pediatric patients. Endotracheal involvement, however, is rare, and has not been previously described with imaging and photographs.An infant with natural killer T-cell deficiency was admitted with cough, rhinorrhea, and cervical lymphadenopathy. Laryngotracheobronchitis-type symptoms persisted and imaging revealed an intraluminal abnormality of the trachea. Endoscopy confirmed a mediastinal lymph node with intrusion into the tracheal lumen. Intraluminal biopsy was deferred due to concerns of airway loss. Biopsy of the associated cervical lymph node confirmed Mycobacterium avium-intracellulare infection. The patient was managed with antibiotics and steroids with clinical resolution of his respiratory symptoms.  相似文献   
993.
《HIV clinical trials》2013,14(4):222-227
Abstract

Purpose: To better characterize the relationship between body mass index (BMI) and CD4+ T-lymphocyte recovery in HIV disease.Methods: We analyzed the association between baseline BMI and CD4+ T-lymphocyte increases, as well as the association between BMI and immune activation (CD38 and HLA-DR co-expression on CD4+ and CD8+ T-lymphocytes), in male HIV-infected patients who achieved viral suppression on antiretroviral therapy (ART).Results: Baseline BMI predicted change in CD4+ T-lymphocyte count at weeks 96 ( P = .03, n = 461) and 144 ( P = .005, n = 357) but not at week 48 ( P = .38, n = 558). Relative to men with a normal BMI, overweight and obese men had increases at week 144 that were 35 and 113 cells/ mm3 higher, respectively, while underweight men had CD4+ T-lymphocyte increases that were 94 cells/mm3 lower. No significant correlations between baseline BMI and cellular immune activation were seen.Conclusions: BMI predicts CD4+ T-lymphocyte gains in men started on ART.  相似文献   
994.
《Clinical neurophysiology》2021,132(10):2510-2518
ObjectiveWe demonstrate the advantages and safety of long, intraorbitally-placed needle electrodes, compared to standard-length subdermal electrodes, when recording lateral rectus electromyography (EMG) during intracranial surgeries.MethodsInsulated 25 mm and uninsulated 13 mm needle electrodes, aimed at the lateral rectus muscle, were placed in parallel during 10 intracranial surgeries, examining spontaneous and stimulation-induced EMG activities. Postoperative complications in these patients were reviewed, alongside additional patients who underwent long electrode placement in the lateral rectus.ResultsIn 40 stimulation-induced recordings from 10 patients, the 25 mm electrodes recorded 6- to 26-fold greater amplitude EMG waveforms than the 13 mm electrodes. The 13 mm electrodes detected greater unwanted volume conduction upon facial nerve stimulation, typically exceeding the amplitude of abducens nerve stimulation. Except for one case with lateral canthus ecchymosis, no clinical or radiographic complications occurred in 36 patients (41 lateral rectus muscles) following needle placement.ConclusionsIntramuscular recordings from long electrode in the lateral rectus offers more reliable EMG monitoring than 13 mm needles, with excellent discrimination between abducens and facial nerve stimulations, and without significant complications from needle placement.SignificanceLong intramuscular electrode within the orbit for lateral rectus EMG recording is practical and reliable for abducens nerve monitoring.  相似文献   
995.
BackgroundUnilateral upper-lung field pulmonary fibrosis (upper-PF), which is radiologically consistent with pleuroparenchymal fibroelastosis, develops after thoracic surgery. In most patients with unilateral upper-PF, aberrant intra-/extra thoracic air commonly emerges and an autopsy shows chronic pleuritis, which indicates that pleural involvement is associated with upper-PF development. If so, there may be patients with unilateral upper-PF who have a history of pleural involvement, including tuberculous pleurisy (TP) or asbestos exposure (AE). This study aimed to examine this supposition.MethodsWe examined the radiological reports of all consecutive patients from 2012 to 2018 to investigate whether there were patients having unilateral upper-PF and a history of TP or AE.ResultsEight patients were included in the study. Five patients had a history of TP, and the remaining three had that of AE. All patients were men and had respiratory symptoms, and seven patients presented with restrictive ventilatory impairment. The interval between TP or last AE and upper-PF development was long, with a median of over 20 years. The upper-PF lesion was commonly located in the right lung, and aberrant intrathoracic air was observed in five patients during their clinical course. Additionally, the upper-PF lesion transformed into a cystic lesion in six patients, which resulted in Aspergillus infection in two patients. The prognosis was poor, with a median overall survival of 38 months.ConclusionsUnilateral upper-PF developed even in patients with a history of pleural involvement. Our results indicate that pleural involvement plays an important role in the development of unilateral upper-PF.  相似文献   
996.
997.
Here, the wavelet analysis has been investigated to improve the quality of myoelectric signal before use in prosthetic design. Effective Surface Electromyogram (SEMG) signals were estimated by first decomposing the obtained signal using wavelet transform and then analysing the decomposed coefficients by threshold methods. With the appropriate choice of wavelet, it is possible to reduce interference noise effectively in the SEMG signal. However, the most effective wavelet for SEMG denoising is chosen by calculating the root mean square value and signal power values. The combined results of root mean square value and signal power shows that wavelet db4 performs the best denoising among the wavelets. Furthermore, time domain and frequency domain methods were applied for SEMG signal analysis to investigate the effect of muscle-force contraction on the signal. It was found that, during sustained contractions, the mean frequency (MNF) and median frequency (MDF) increase as muscle force levels increase.  相似文献   
998.
999.
张楠楠  高超  邱渝杰 《医学综述》2014,(8):1401-1403
肥胖患病率已经达到流行病的程度,肥胖是多种癌症发生的重要危险因素,例如大肠癌、乳腺癌、子宫内膜癌、前列腺癌、甲状腺癌等。体质量指数作为最常用的肥胖替代指标,可较好地反映肥胖癌症患者的临床特征、治疗疗效及预后。历年研究显示,对于肥胖与癌症关系的各临床研究得到的结论并不完全趋于一致。肥胖作为大多数常见癌症的一个重要危险因素,其作用机制的研究结果尚不明晰,从肥胖到癌症的发生、发展过程中干扰因素非常多,临床研究应根据需要适当选用,通过更有力的证据找出两者的关系,以期减少癌症的发生、发展,提高癌症患者预后的生活质量。  相似文献   
1000.
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