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101.
Intractable tinnitus can lead to serious consequences. Study evidence indicates that the central nervous system is involved in generation and maintenance of chronic tinnitus and that tinnitus and other neurologic symptoms such as chronic pain may share similar mechanisms. Brain ablation and stimulation are used to treat chronic pain with success. Recent studies showed that ablation and stimulation in non-auditory areas resulted in tinnitus improvement. Deep brain stimulation (DBS) may be an alternative treatment for intractable tinnitus and deserves further study. 相似文献
102.
无国界医生致力于应对天灾和战祸所引起的人道医疗危机。灾后实时爆发的人道医疗危机包括急性的外科创伤问题和基础医疗系统的破坏导致疫症发生。本文介绍了无国界医生的救援经验以及专业的备灾体系。 相似文献
103.
左旋布比卡因复合舒芬太尼或芬太尼在分娩硬膜外自控镇痛的应用 总被引:1,自引:0,他引:1
目的探讨左旋布比卡因复合舒芬太尼硬膜外自控镇痛(PCEA)用于分娩镇痛的临床效果及安全性。方法随机选择120例美国标准协会(ASA)I-Ⅱ级初产妇,随机分为舒芬太尼组(A组)、芬太尼组(B组)、无镇痛组(C组),每组40例。A组和B组采用PCEA,C组不给予镇痛药物。观察各组不同时段视觉模拟评分(VAS)和不良反应的发生,同时记录3组产程时间、分娩方式、缩宫使用情况、产后出血量、新生儿Apgar评分。结果A、B2组和C组在PCEA20、60min及宫口开全时VAS差异有统计学意义(P〈0.05);PCEA5min,A、B2组VAS差异有统计学意义(P〈0.05),2组Bromage评分、不良反应差异无统计学意义(P〉0.05)。3组产程时间、分娩方式、产后出血量、新生儿Apgar评分比较差异均无统计学意义(P〉0.05)。结论左旋布比卡因复合舒芬太尼或芬太尼用于分娩镇痛安全有效,对母婴无明显不良影响。 相似文献
104.
目的观察半乳糖化白蛋白磁性阿霉素纳米粒(ADR-GHMN)在正常肝脏中的靶向性,并观察ADR-GHMN在全身各脏器的分布特征及外加磁场对其分布的影响.方法大鼠正中开腹,肝动脉插管并固定,肝动脉注射125I-ADR-GHMN(相当于阿霉素0.5 mg/kg),左外叶加磁场,磁场应用30 min,移去磁场后,动物立即处死;对照组:肝动脉注射ADR-GHMN,左外叶不加磁场,30min后,移去磁场后,动物立即处死,立即取靶区肝、非靶区肝、肾、心、肺、小肠、脾及周围血作γ计数.肝组织作病理切片.结果注入的纳米粒75~85%分布于肝脏,其它脏器极少.病理切片显示磁区小动脉见大量纳米粒存在,对照组及非磁区肝中纳米粒很少见.结论ADR-GHMN在正常肝组织中有明显的磁靶向性;在磁场作用下,ADR-GHMN主要分布于肝脏,其它脏器含量很少;试验组肾、心、肺、小肠、脾及外周血于对照组的放射活性比较明显降低,表明磁性物质的存在使这些脏器的相对药物暴露明显减少. 相似文献
105.
目的:分析探讨CT、MRI诊断对肾上腺病变的作用与价值。方法:MarconiMX8000 4层螺旋CT机,增强造影剂使用非离子型制剂,常规扫描及增强。应用西门子MAGNETOM1.5T磁共振机,增强造影剂使用Gd-DTPA制剂,常规T1WI、T2WI、脂肪抑制、化学位移同反相位及增强。对25例经手术及病理资料诊断证实的肾上腺病变进行CT、MRI诊断回顾性分析。结果:可清楚显示肾上腺病变的侧别、数目、大小、范围及可能的性质。结论:CT是肾上腺病变最佳影像检查方法,MRI具有重要辅助及补充诊断价值。 相似文献
106.
使用抗体-生物纳米磁珠复合体的免疫凝集检测法 总被引:4,自引:0,他引:4
解宇 《中国生物医学工程学报》2005,24(6):740-742,762
使用从磁性细菌体内提取的生物纳米磁珠,在磁珠表面联上特定的抗体,以玻片免疫凝集检测法检测癌胚抗原(carcinoembryonic AntigenCEA)。结果表明使用5μg的CEA抗体-磁珠复合体,可以检测出100pg/ml浓度的CEA,在操作性、经济性上优于免疫荧光检测法。 相似文献
107.
Ashish Raj Honglei Zhang Martin R Prince Yi Wang Ramin Zabih 《Magnetic resonance in medicine》2006,55(3):649-658
Time-resolved contrast enhanced magnetic resonance angiography (MRA) may suffer from involuntary patient motion. It is noted that while MR signal change associated with motion is large in magnitude and has smooth phase variation in k-phase, signal change associated with vascular enhancement is small in magnitude and has rapid phase variation in k-space. Based upon this observation, a novel projection onto convex sets (POCS) algorithm is developed as an automatic iterative method to remove motion artifacts. The presented POCS algorithm consists of high-pass phase filtering and convex projections in both k-space and image space. Without input of detailed motion knowledge, motion effects are filtered out, while vasculature information is preserved. The proposed method can be effective for a large class of nonrigid motions, including through-plane motion. The algorithm is stable and converges quickly, usually within five iterations. A double-blind evaluation on a set of clinical MRA cases shows that a completely unsupervised version of the algorithm produces significantly better rank scores (P=0.038) when compared to angiograms produced manually by an experienced radiologist. 相似文献
108.
目的:基于累及头颈部淋巴组织病变的临床不典型性,旨在探讨MRI对其进行鉴别诊断的客观依据。方法:对本组22例可疑累及头颈部淋巴组织的各类病变进行MRI检查并与病理学结果进行对照。结果:MRI对本组22例累及淋巴组织病变的诊断与病理学诊断的符合率(21/22)约为95%。结论:MRI是对累及头颈部淋巴组织病变的重要检查手段,并能为明确其诊断提供客观依据。 相似文献
109.
Cerebrospinal fluid and plasma concentrations of oxytocin and vasopressin during parturition and vaginocervical stimulation in the sheep 总被引:1,自引:0,他引:1
Simultaneous blood and cerebrospinal fluid (CSF) samples were taken from conscious sheep before, during and after parturition. Concentrations of plasma and CSF oxytocin were significantly elevated during contractions and particularly at birth. Mean prepartum CSF concentrations of oxytocin were around 55% of those found in plasma but postpartum they were up to 2-fold higher than those in plasma. Plasma concentrations of oxytocin were only significantly elevated, compared to prepartum levels, for 15 min postpartum whereas those in CSF were increased for the whole of the 120 min postpartum sampling period. Plasma, but not CSF, concentrations of arginine-vasopressin (AVP) were significantly raised during contractions and birth, and for 15 min postpartum. During the prepartum period CSF AVP concentrations were 67% of those found in plasma whereas at birth plasma levels were 10-fold higher than in CSF. In a separate experiment it was shown that 5 min of mechanical vaginocervical stimulation also stimulated significant increases in CSF and plasma oxytocin concentrations and in plasma vasopressin. Results support previous work suggesting an important role for central oxytocin release in the postpartum induction of maternal behavior and demonstrate that elevated concentrations of oxytocin in the CSF are present for a greater period than in blood. Elevated plasma AVP concentrations during contractions, birth or vaginocervical stimulation may be stimulated by stress associated with these stimuli. 相似文献
110.
Abstract: The use of neuromuscular electrical stimulation (NMES) for rehabilitation of gait in spinal patients is widely known. The best results can be obtained with the use of biomechanical sensors and a closed loop NMES system. One of the biggest problems faced in the design of control systems for closed-loop operation, in gait rehabilitation, is the variation of the mechanical conditions during the phases of gait. This work presents a new approach to ease the design of rule-based closed loop systems for operation in conditions such as gait rehabilitation. 相似文献