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111.
To identify biomarkers of ethyl (1-(diethylamino)ethylidene)phosphoramidofluoridate (A234)- or methyl (1-(diethylamino)ethylidene)phosphoramidofluoridate (A232)-inhibited butyrylcholinesterase (BChE), we investigated nonapeptide adducts containing the active site serine, which plays a key role in enzyme activity, using LC-MS/HRMS. Biomarkers were acquired as expected, and they exhibited a significant amount of fragment ions from the inhibiting agent itself, in contrast to the MS2 spectra of conventional nerve agents. These biomarkers had a higher abundance of [M+2H]2+ ions than [M+H]+ ions, making doubly charged ions more suitable for trace analysis.  相似文献   
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To study the role of proprioception in voluntary movement, two monkeys were trained to use their mandible to control the position of a lever that electronically loaded the jaw. They “tracked” stationary and moving targets both with and without visual feedback. Lesions of the tract of the mesencephalic nucleus of the fifth nerve, which destroyed most jaw muscle proprioceptors, did not interfere, even transiently, with the ability to perform the basic requirements of the jaw tracking tasks. There was an increase in low-frequency jaw tremor, and a small increase in the tracking error when the visual feedback signal was present, but these effects may have resulted from damage to other neural pathways. We conclude that muscle spindles are not necessary to perform well-practiced movements.  相似文献   
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本研究探讨磁共振成像(MRI)检查神经根沉降征(NRS)在腰椎管狭窄症(LSS)患者发生中的相关因素及其诊断学价值。选取接受腰椎MRI检查的262例(511个腰椎节段)患者进行研究,根据MRI结果患者腰椎节段分为狭窄组(172例患者,348个腰椎节段)和非狭窄组(90例患者,163个腰椎节段)。狭窄组硬膜囊面积(CSA)<100 mm2患者占比、椎管正中矢状径(PDA)≤15 mm患者占比、侧隐窝矢状径≤5 mm患者占比、神经根沉降征(NRS)阳性率均显著高于非狭窄组(P<0.05);NRS诊断LSS的曲线下面积(AUC)值为0.714;172例LSS患者,NRS阳性患者108例、NRS阴性患者64例,NRS阳性组的糖尿病率、硬膜囊CSA<100 mm2患者占比、椎管PDA≤15 mm患者占比、侧隐窝矢状径≤5 mm患者占比均高于阴性组患者,差异均具有统计学意义(P<0.05);硬膜囊CSA<100 mm2、椎管PDA≤15 mm、侧隐窝矢状径≤5 mm是LSS患者发生NRS的独立危险因素(P<0.05)。NRS对于诊断LSS具有较高的特异度,但是灵敏度一般,患者椎管狭窄越严重,其NRS发生的风险越高。  相似文献   
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A field‐portable gas chromatography–mass spectrometry (GC–MS) system (Hapsite ER) was evaluated for the detection of nonvolatile V‐type nerve agents (VX and Russian VX (RVX)) in the vapor phase. The Hapsite ER system consists of a Tri‐Bed concentrator gas sampler, a nonpolar low thermal‐mass capillary GC column and a hydrophobic membrane‐interfaced electron ionization quadrupole mass spectrometer evacuated by a non‐evaporative getter pump. The GC–MS system was attached to a VX‐G fluoridating conversion tube containing silver nitrate and potassium fluoride. Sample vapors of VX and RVX were converted into O‐ethyl methylphosphonofluoridate (EtGB) and O‐isobutyl methylphosphonofluoridate (iBuGB), respectively. These fluoridated derivatives were detected within 10 min. No compounds were detected when the VX and RVX samples were analyzed without the conversion tube. A vapor sample of tabun (GA) was analyzed, in which GA and O‐ethyl N,N‐dimethylphosphoramidofluoridate were detected. The molar recovery percentages of EtGB and iBuGB from VX and RVX vapors varied from 0.3 to 17%, which was attributed to variations in the vaporization efficiency of the glass vapor container. The conversion efficiencies of the VX‐G conversion tube for VX and RVX to their phosphonate derivatives were estimated to be 40%. VX and RVX vapors were detected at concentrations as low as 0.3 mg m−3. Gasoline vapor was found to interfere with the analyses of VX and RVX. In the presence of 160 mg m−3 gasoline, the detection limits of VX and RVX vapor were increased to 20 mg m−3. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
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目的分析并研究早期多药联合干预对早产儿脑白质软化的治疗效果。方法将珠海市妇幼保健院收治的早产儿脑白质软化患儿68例作为研究对象,随机将患儿分为两组,每组各34例,其中对对照组患儿实施常规治疗方式,给予观察组患儿在常规治疗的基础上实施早期多药(神经节苷脂、1,6-二磷酸果糖和鼠神经生长因子)联合干预治疗,同时分别给予两组患儿脑白质损伤程度比较,并于患儿1岁时进行智力发育指数和心理运动发育指数的评价比较。结果观察组患儿脑白质损伤轻度显著高于对照组患儿,脑白质损伤重度显著低于对照组患儿,数据比较差异具有统计学意义(P0.05);观察组患儿智力发育指数与心理运动发育指数均显著高于对照组患儿,数据比较差异具有统计学意义(P0.05)。结论对早产儿脑白质软化患儿采用神经节苷脂、1,6-二磷酸果糖和鼠神经生长因子等多药早期治疗能够明显缓解患儿脑白质软化持续性病变的发展,治疗效果显著。  相似文献   
118.
Peripheral nerve regeneration has been evaluated using a biodegradable nerve conduit, which is made of a 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide (EDC)/N-hydroxysuccinimide (NHS) cross-linked gelatin. The EDC/NHS crosslinked gelatin (ENG) conduit is brownish in appearance, and is concentric and round with a smooth outer surface and inner lumen. After subcutaneous implantation on the dorsal side of a rat, the degraded ENG conduit only evoked a mild tissue response, with the formation of a thin tissue capsule surrounding the conduit. Biodegradability of the ENG conduit and its effectiveness as a guidance channel has been examined by its use to repair a 10 mm gap in the rat sciatic nerve. As a result, the tubes degraded throughout the implantation period, but still remained circular with a thin round lumen until they were completely integrated with the enclosed nerves. Successful regeneration through the gap occurred in all the conduits over the three experimental periods of 4, 8, and 12 weeks. Histological observation showed that numerous myelinated axons had crossed through the gap region even at the shortest implantation period of 4 weeks. Peak amplitude, area under the muscle action potential curve, and nerve conductive velocity all showed an increase as a function of the recovery period, which indicates that the nerve had undergone adequate regeneration. These results indicate the superiority of the ENG materials and suggest that the novel ENG conduits provide a promising tool for neuro-regeneration.  相似文献   
119.
Vocal cord medialization through Isshiki type I thyroplasty is part of the standard approach for patients with unilateral vocal cord immobility secondary to recurrent laryngeal nerve paralysis. However, several other modalities have been used to treat the symptomatic “twisted” larynx caused by unilateral superior laryngeal nerve weakness. The Isshiki type IV thyroplasty (cricothyroid approximation) specifically addresses cricothyroid muscle weakness, but, canine studies at the Mayo Clinic demonstrated a trend toward decreased acoustic power and sound intensity with simulated cricothyroid activity. Thus it is reasoned that addition of an ipsilateral type I thyroplasty should help compensate for this power loss.Using videostroboscopic and acoustic analysis, 9 patients with unilateral superor laryngeal nerve weakness were treated with combination type IV and type I thyroplasty. Subjective dysphonia and objective visual and acoustic measurements revealed postoperative improvement in most patients. The combination type IV and type I thyroplasty is recommended for surgical treatment of patients with superior laryngeal nerve weakness, because it addresses cricothyroid muscle weakness without compromising vocal power.  相似文献   
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肩关节前上外侧手术入路的应用解剖   总被引:5,自引:0,他引:5  
目的为肩关节前上外侧手术入路提供解剖学依据.方法按照手术入路和层次,对25例成年尸体50侧上肢标本作了解剖观测.结果三角肌前外侧部起点长度为(8.73±0.64)cm,三角肌肩峰外侧端起点至三角肌粗隆长(15.49±1.57)cm.腋神经前支于肩峰外侧端与三角肌止点连线相交点位于肩峰下(6.19±0.49)cm,相当于肩峰与三角肌止点连线间三角肌长度的上2/5与下3/5交点.结论手术横行切口,从肩峰沿锁骨向内侧不超过(8.73±0.64)cm,否则容易损伤位于三角肌胸大肌间隙内的头静脉、胸肩峰动脉和胸外侧神经.纵行切口,从肩峰向下不超过(6.19±0.49)cm,也就是说此纵切口不超过三角肌中线长度的上2/5.以防损伤腋神经前支及旋肱后动、静脉等.  相似文献   
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