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101.
102.
Aiguo Shen Benjian Zhang Jie Ping Wei Xie Patrice Donfack Seong‐Joon Baek Xiaodong Zhou Hui Wang Arnulf Materny Jiming Hu 《Journal of Raman spectroscopy : JRS》2009,40(5):550-555
Micro‐Raman spectroscopy (MRS) was utilized for the first time to evaluate the effect of indole‐3‐carbinol (I3C) on acute alcoholic liver injury in vivo. In situ Raman analysis of tissue sections provided distinct spectra that can be used to distinguish alcoholic liver injury as well as ethanol‐induced liver fibrosis from the normal state. Sixteen mice with liver diseases including acute liver injury and chronic liver fibrosis, and eight mice with normal liver tissues, and eight remedial mice were studied employing the Raman spectroscopic technique in conjunction with biomedical assays. The biochemical changes in mouse liver tissue when liver injury/fibrosis occurs such as the loss of reduced glutathione (GSH), and the increase of collagen (α‐helix protein) were observed by MRS. The intensity ratio of two Raman peaks (I1450/I666) and in combination with statistical analysis of the entire Raman spectrum was found capable of classifying liver tissues with different pathological features. Raman spectroscopy therefore is an important candidate for a nondestructive in vivo screening of the effect of drug treatment on liver disease, which potentially decreases the time‐consuming clinical trials. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
103.
Ji-Eun Lee Hyonchol Jang Eun-Jung Cho Hong-Duk Youn 《Experimental & molecular medicine》2009,41(7):471-477
Down syndrome critical region 1 (DSCR1), an oxidative stress-response gene, interacts with calcineurin and represses its phosphatase activity. Recently it was shown that hydrogen peroxide inactivates calcineurin by proteolytic cleavage. Based on these facts, we investigated whether oxidative stress affects DSCR1-mediated inactivation of calcineurin. We determined that overexpression of DSCR1 leads to increased proteolytic cleavage of calcineurin. Convertsely, knockdown of DSCR1 abolished calcineurin cleavage upon treatment with hydrogen peroxide. The PXIIXT motif in the COOH-terminus of DSCR1 is responsible for both binding and cleavage of calcineurin. The knockdown of overexpressed DSCR1 in DS fibroblast cells also abrogated calcineurin proteolysis by hydrogen peroxide. These results suggest that DSCR1 has the ability to inactivate calcineurin by inducing proteolytic cleavage of calcineurin upon oxidative stress. 相似文献
104.
Microchip electrophoresis is a promising technique for analysis of bio-molecules. It has the advantages of fast analysis, high sensitivity, high resolution and low-cost of samples. Plastic chip has the potential of mass production for clinical use for its advantages in biocompatibility and low cost. In this work, the method for fabrication of poly(methyl methacrylate) (PMMA) chip was described, and conditions for DNA separation were investigated with the chip. The PMMA microchip was used for detection of multiplex PCR products of 18 and 36 cases with SARS and hepatitis B virus infection under optimized separation conditions. Microchip electrophoresis showed higher sensitivity, higher resolution and less time consumption when compared with gel electrophoresis. The microchip electrophoresis with PMMA chip provided a rapid, sensitive and reliable method for analysis of multiplex PCR products. 相似文献
105.
电影胶片是一类重要的历史文化遗产,也是国家档案保存的重要组成部分.三醋酸纤维素酯电影胶片是馆藏最多的一类影片,然而其片基构成材料三醋酸纤维素酯水解而产生的醋酸综合症是危害其安全存贮的主要病害,被称为电影胶片的“癌症”.本文分析了醋酸综合症产生的原因,介绍了醋酸综合症的危害及预防电影胶片发生醋酸综合症的措施. 相似文献
106.
JPEG图像是最流行的隐写载体之一,但隐写分析的最新进展表明,如何设计安全的JPEG隐写算法仍是一个困难的问题.本文提出了一种新的JPEG自适应隐写方法.自适应隐写难点在于设计失真函数合理反应修改量化DCT系数造成的嵌入失真.由于量化DCT系数绝对值的大小能够反应JPEG图像主要统计特性,本文根据DCT系数大小关系设计失真函数,结合STC(Syndrome Trellis Codes)编码,分别给出了使用nsF5修改方式的单层嵌入方法以及使用加减一修改方式的双层嵌入方法.实验表明,本文单层嵌入方法比nsF5安全性高,双层嵌入方法比nsF5以及Filler’s Method抵抗多种检测的能力更强. 相似文献
107.
我国海域辽阔,各类船只的水上航行和作业安全密切关系到生命和财产的安全,需要可靠保障。由于海上险情发生的随机性和突发性,岸上险情监视力量必须全时、全天候地开设险情通信通道,接收海上遇险对象的遇险呼救信号并及时对遇险信息进行处理。因此,岸基必须建设遇险救生信息系统并规定必要的信息传输流程,保障险情报知通信的顺利完成。文章简要分析了目前海上救生的通信现状,对常用通信手段进行了分析与介绍,并提出了一种整合各通信手段的设计方法,实现了多种通信手段的综合使用以及统一调度,大幅提升险情信息的传输和处理效率,提高险情信息的保密性,为救援工作提供了精确可靠的问责手段。 相似文献
108.
利用呼吸感应体积描记(RIP)技术测量呼吸参数已得到了越来越广泛的认可,针对人体呼吸运动引起传感线圈的电感量变化非常小(小于几百nH),一般系统难以保证精确性和适用性问题;硬件设计采用了高精度恒流源,锁相放大和自动增益控制放大电路,并详细分析了各部分电路的特性,包括在平静呼吸和用力呼吸模式下分别对14位测试者测量潮气量和呼吸频率,并且与德国耶格公司的肺功能仪所测量的结果对比;实验证明RIP系统在这两种模式下测量潮气量和呼吸频率等呼吸参数与速度描记仪存在显著的正相关关系,说明该系统工作良好、测量精确,操作简单、便于携带和低功耗,未来可以在临床上推广应用于长时间动态的呼吸监测。 相似文献
109.
Paroxysmal vocal cord movement/motion (PVCM), paroxysmal vocal cord dysfunction (PVCD), episodic paroxysmal laryngospasm (EPL), and irritable larynx syndrome (ILS) are terms used to describe laryngeal dysfunction masquerading as asthma, upper airway obstruction, or functional and organic voice disorders. The differential diagnosis of PVCM, PVCD, EPL, and ILS is critical to successful medical and behavioral management of the patient. During the past 10 years, 27 subjects, ages 15–79 years, were identified to have paroxysms of inspiratory stridor, acute respiratory distress, associated aphonia and dysphonia, resulting in misdiagnosis and unnecessary emergency treatments, including endotracheal intubation, cardiopulmonary resuscitation, massive pharmacotherapy, or tracheostomy. A multifactorial management program is proposed utilizing principles of motor learning, neurolinguistic programming model, respiratory and phonatory synchronization, relaxation techniques, concurrent monitoring of behavioral adjustments, and formal psychological counseling. 相似文献
110.
Shen Yu Ying-Xi Liu Xiu-Zhen Sun Ying-Feng Su Ying Wang Yin-Zhe Gai 《Acta Mechanica Sinica》2014,30(2):250-258
In the present study, we reconstructed upper airway and soft palate models of 3 obstructive sleep apnea-hypopnea syndrome(OSAHS) patients with nasal obstruction. The airflow distribution and movement of the soft palate before and after surgery were described by a numerical simulation method. The curative effect of nasal surgery was evaluated for the three patients with OSAHS. The degree of nasal obstruction in the 3 patients was improved after surgery. For 2 patients with mild OSAHS, the upper airway resistance and soft palate displacement were reduced after surgery. These changes contributed to the mitigation of respiratory airflow limitation. For the patient with severe OSAHS, the upper airway resistance and soft palate displacement increased after surgery, which aggravated the airway obstruction. The effcacy of nasal surgery for patients with OSAHS is determined by the degree of improvement in nasal obstruction and whether the effects on the pharynx are beneficial. Numerical simulation results are consistent with the polysomnogram(PSG) test results, chief complaints, and clinical findings, and can indirectly reflect the degree of nasal patency and improvement of snoring symptoms, and further,provide a theoretical basis to solve relevant clinical problems. 相似文献