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961.
Ricin is one of the most poisonous natural toxins from plants and is classified as a Class B biological threat pathogen by the Centers for Disease Control and Prevention (CDC) of U.S.A. Ricin exposure can occur through oral or aerosol routes. Ricin poisoning has a rapid onset and a short incubation period. There is no effective treatment for ricin poisoning. In this study, an aerosolized ricin-exposed mouse model was developed and the pathology was investigated. The protein expression profile in the ricin-poisoned mouse lung tissue was analyzed using proteomic techniques to determine the proteins that were closely related to the toxicity of ricin. 2D gel electrophoresis, mass spectrometry and subsequent biological functional analysis revealed that six proteins including Apoa1 apolipoprotein, Ywhaz 14-3-3 protein, Prdx6 Uncharacterized Protein, Selenium-binding protein 1, HMGB1, and DPYL-2, were highly related to ricin poisoning.  相似文献   
962.
Chrysin (CH), a natural plant flavonoid, has shown a variety of beneficial effects. Our present study was conducted to evaluate the therapeutic potential of CH three days after spinal cord injury (SCI) in rats and to probe the underlying neuroprotective mechanisms. SCI was induced using the modified weight-drop method in Wistar rats. Then, they were treated with saline or CH by doses of 30 and 100 mg/kg for 26 days. Neuronal function was assessed with the Basso Beattle Bresnahan locomotor rating scale (BBB). The water content of spinal cord was determined after traumatic SCI. The NF-κB p65 unit, TNF-α, IL-1β and IL-6 in serums, as well as the apoptotic marker, caspase-3, of spinal cord tissues were measured using commercial kits. The protein level and activity of inducible nitric oxide synthase (iNOS) were detected by western blot and a commercial kit, respectively. NO (nitric oxide) production was evaluated by the determination of nitrite concentration. The rats with SCI showed marked reductions in BBB scores, coupled with increases in the water content of spinal cord, the NF-κB p65 unit, TNF-α, IL-1β, IL-6, iNOS, NO production and caspase-3. However, a CH supplement dramatically promoted the recovery of neuronal function and suppressed the inflammatory factors, as well as the iNOS pathway in rats with SCI. Our findings disclose that CH improved neural function after SCI in rats, which might be linked with suppressing inflammation and the iNOS pathway.  相似文献   
963.
Whether or how neural stem cells (NSCs) respond to toll-like receptor 4 (TLR4) in an inflammatory environment caused by traumatic brain injury (TBI) has not been understood. In the present study, association between TLR4 expression and NSCs proliferation in the hippocampus was investigated in a mouse model of TBI using controlled cortical impact (CCI). Hippocampal proliferating cells were labeled with the thymidine analog 5-bromo-2-deoxyuridine (BrdU). In order to identify NSCs, the proliferating cells were further co-labeled with BrdU/sex determination region of Y chromosome related high mobility group box gene 2 (SOX2). Morphological observation on the expression of BrdU, SOX2, and TLR4 in the hippocampus was performed by inmmunofluorescence (IF). Relative quantification of TLR4 expression at the protein and mRNA level was performed using Western blotting and real-time polymerase chain reaction (PCR). It was observed that BrdU+/SOX2+ cells accounted for 95.80% ± 7.91% among BrdU+ cells; several BrdU+ cells and SOX2+ cells in the hippocampus were also TLR4-positive post injury, and that BrdU+ cell numbers, together with TLR4 expression at either protein or mRNA level, increased significantly in TBI mice over 1, 3, 7, 14, and 21 days survivals and changed in a similar temporal pattern with a peak at 3 day post-injury. These results indicate that hippocampal proliferating cells (suggestive of NSCs) expressed TLR4, and that there was a potential association between increased expression of TLR4 and the proliferation of NSCs post TBI. It is concluded that hippocampal TLR4 may play a potential role in endogenous neurogenesis after TBI.  相似文献   
964.
蒋涛  宫琴 《仪器仪表学报》2015,36(7):1673-1680
为了开发电子耳蜗调试平台的体内系统,帮助电子耳蜗佩戴者个体选择最适用的言语编码策略并对其工作参数进行调试,本研究采用数据扩展编码和嵌入式脉冲控制的方式,由单片机采集言语编码序列的数据帧并解码得到刺激参数,控制输出刺激脉冲。刺激脉冲的输出通道和幅度由前一帧的刺激参数决定,脉冲宽度由当前帧的长度控制,实现了调试平台的工作参数对输出刺激脉冲的控制功能。完成了基于嵌入式脉冲控制功能的电子耳蜗调试平台体内系统的设计与调试,通过对调试平台的单电极刺激模式和非实时模式的测试,验证了所设计的调试平台体内系统具有输出连续、稳定的刺激脉冲的功能。  相似文献   
965.
Cochlear implant (CI) provides good auditory performances in quiet, but recognition in noisy environments is still a challenge for CI users. Bilateral hearing can improve speech perception; it has been shown with normal hearing aids, but how source localization is affected is still an open question.In this study source localization is studied in the case of a binaural cochlear implant coding. Signal was received on the two ears and then processed using the classical noise reduction algorithm, suggested by Doerbecker and based on the spectral properties of the signal. Two correction strategies, Ephreim & Malah and Scalart, have been inserted in the processing chain.Tests were conducted, “in simulation” with 20 normal hearing listeners who received a cochlear implant coded signal. An analytic interpretation of the results offers a frame to quantify the different contributions.Results show that the Doerbecker’s algorithm affects the source localization. This effect was lowered when a percentage of the input signal was re-injected into the system. Both correction strategies were equivalent.  相似文献   
966.
目的探讨皮肤软组织扩张器植入在烧伤整形中的临床应用价值。方法 I期手术根据组织部位特点植入扩张器,注水扩张皮肤,II期手术利用扩张皮瓣修复缺损区。结果 83例中有75例利用扩张皮肤形成局部皮瓣一次完成整形,修复后的皮肤质地和色泽与受区接近,随访6个月至1年,效果满意。结论运用皮肤扩张术进行烧伤整形是一种较为理想的修复方法,通过各种措施可减少手术并发症,提高成功率。  相似文献   
967.
目的: 观察川芎嗪对儿茶酚胺诱导大鼠心肌损伤时心肌细胞Bcl-2 和Fas 蛋白表达的影响。方法: 采用皮下多点注射异丙肾上腺素(ISO,5 mg·kg-1) 每天1 次, 连续3 d, 诱导大鼠心肌损伤,采用免疫组化方法检测Bcl-2 和Fas 蛋白的水平, 并利用图像分析系统分析蛋白阳性表达区域平均光密度值。结果: 损伤组和川芎嗪保护组心肌细胞Bcl-2蛋白表达较对照组均显著升高(P<0.01), 损伤组Fas 蛋白水平较对照组也显著升高(P<0.01), 川芎嗪保护组的Fas 蛋白水平较损伤组显著下降(P<0.01), 且Bcl-2 Fas 比值也较损伤组和对照组明显增加。川芎嗪保护组的病理损伤程度明显低于损伤组。结论: 川芎嗪可抑制儿茶酚胺诱导的心肌损伤时心肌细胞中促凋亡基因Fas 的表达, 提高心肌细胞中Bcl-2 Fas 比值。  相似文献   
968.
徐隽  余涓  王晶  林春  陈崇宏 《金属学报》2004,9(3):294-298
目的:探讨蕲蛇酶(acutobin) 在局灶性脑缺血再灌注损伤模型中的保护作用及其机制。方法:线栓法制备大鼠大脑中动脉闭塞(MCAO) 模型, 缺血3 h 后恢复血流再灌24 h 。观察蕲蛇酶对脑梗死面积、脑组织中髓过氧化物酶(MPO)、诱导型一氧化氮合酶(iNOS) 活性、一氧化氮(NO)、丙二醛(MDA) 含量和超氧化物歧化酶(SOD) 活性的影响。结果:蕲蛇酶能有效减小脑梗死灶, 缓解MPO 升高、降低MDA 含量、抑制iNOS 活性, 降低NO 含量。结论:蕲蛇酶对脑缺血再灌注损伤有保护作用, 其机制可能与缓解MPO 升高以及抑制脑组织中iNOS 活性, 降低NO、MDA 含量有关。  相似文献   
969.
目的:观察小牛血去蛋白提取物注射液(deproteinized extract of calf blood, DECB) 对培养的心肌细胞缺氧再给氧损伤的保护作用。方法:以培养的心肌细胞为模型, 在缺氧再给氧损伤细胞后, 观察心肌细胞活力及搏动频率的变化, 测定培养液上清乳酸脱氢酶的含量。结果:DECB 0.1 及0.3 g·L-1可以提高损伤后心肌细胞的活力, 提高心肌细胞的搏动频率, 并使培养液上清乳酸脱氢酶的含量明显降低。结论:DECB 对缺氧再给氧损伤培养的心肌细胞具有保护作用。  相似文献   
970.
目的 观察益智胶囊对大鼠全脑缺血后海马CA1 区神经元迟发性死亡及学习功能的影响。 方法 使用四血管闭塞(4-VO) 法制成大鼠急性全脑缺血再灌注模型。采用免疫组织化学方法计数脑缺血再灌注脑损伤后1、2、4、8 及40 d 后, 大鼠海马CA1区正常神经元数量;并用Morriss 水迷宫观察脑缺血再灌注脑损伤后40 d 时各组大鼠的学习记忆功能。 结果 从缺血再灌注后d 2 起, 益智胶囊(100 mg·kg-1) 组大鼠海马CA1 区正常神经元数量明显多于缺血对照组大鼠海马CA1 区正常神经元数量, 差异有明显统计学意义(P <0.01)。同时,Morris 水迷宫法检测全脑缺血再灌注脑损伤后40 d时各组大鼠记忆功能, 益智胶囊(100 mg·kg-1) 组大鼠明显好于缺血对照组大鼠(P <0.01)。 结论 益智胶囊对全脑缺血后大鼠海马CA1 区神经元具有保护作用, 并可改善大鼠的记忆功能障碍。  相似文献   
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