Peripheral nerve stimulation during MRI: Effects of high gradient amplitudes and switching rates

The application of high gradient amplitudes and switching rates for MRI and spectroscopy, resulting in short rise times for the gradient field and high changes of the magnetic flux density in the patient, is known to possibly evoke peripheral nerve stimulation (PNS) in patients. These effects have been studied on 20 volunteers under different experimental circumstances. The results of these measurements are partially in line with earlier findings reported in the literature. New information is found for the dependence of the PNS threshold level as a function of the rise time of the gradient waveform. The PNS threshold level, expressed in terms of dB/dt, is found to be proportional with t^?05, where t is the switch time for the gradients. Indications are found that |B|, the modulus of the gradient vector field, is more closely related to the PNS threshold level than B_z, the imaging component of the gradient field. From the experiments, it is furthermore concluded that only for the imaging protocols characterized by the application of long bipolar repetitive gradient pulse trains, such as echo-planar imaging, PNS is expected at the reported threshold levels. For the protocols based on spin echo, turbo spin echo, inversion recovery, fast field echo, etc., characterized by shorter gradient pulse trains, the threshold levels are expected to be much higher.     

吉林放射事故病人血浆造血活性观察

目的观察病人血浆造血活性，了解其与照后造血功能变化的可能关系。方法以ＭＴＴ法测病人血浆对ＮＦＳ－６０、ＴＦ－１和ＢＥＴ－２细胞因子依赖细胞株在有或无相应细胞因子存在时的吸光度（４９２ｎｍ）。结果患者血清有类似ＧＭ－ＣＳＦ、ＩＬ－３和ＥＰＯ的刺激活性。血浆加入含ｒｈＧ－ＣＳＦ和ＥＰＯ的培养体系中可使ＮＦＳ－６０和ＢＥＴ－２细胞增殖受抑。上述变化与病人外周血白细胞、红细胞及血红蛋白的变化有相关之处。结论吉林辐射事故病人血浆中有粒系和红系造血抑制活性。     

猴头菇发酵茶安全性检测及对大鼠胃酸分泌的影响

目的：检测猴头菇发酵茶的安全性并观察猴头菇发酵茶对大鼠胃酸分泌的影响。方法：猴头菇发酵茶安全性测定按GBl5193．1-94《食品安全性毒理学评价程序》要求进行；用酸度计测定大鼠胃液pH值。结果：猴头菇发酵茶对小鼠的半数致死量为15．11g／kg，且无诱发小鼠骨髓细胞微核形成，不同剂量的猴头菇发酵茶对大鼠胃酸分泌有促进和抑制的作用。结论：猴头菇发酵茶安全无毒，高剂量时对大鼠胃酸分泌有抑制作用。     

第1产程潜伏期指导对分娩的影响

目的 :观察规范指导对处于分娩第 1产程潜伏期孕妇的影响。方法 :为处于分娩第 1产程潜伏期的 15 0例产妇讲解分娩知识 ,训练助产动作 ,树立自然分娩信心 ,并动态观察产妇的分娩情况。以条件相同 ,未在潜伏期做指导的产妇 15 0例为对照组。结果 :观察组总产程、第 1产程活跃期及第 2产程明显短于对照组 (P <0 0 1) ,新生儿窒息率、剖宫产率明显低于对照组(P <0 0 1)。第 1产程潜伏期、阴道助产率及产后出血发生率两组差异无显著性。结论 :在第 1产程潜伏期对产妇进行规范指导可以缩短产程 ,促进自然分娩 ,降低新生儿窒息发生率。     

盐酸齐拉西酮在中国健康志愿者中的药代动力学研究

目的评价国产盐酸齐拉西酮胶囊的人体药代动力学特点;初步评价国产盐酸齐拉西酮胶囊的安全性。方法采用HPLC法测定血浆中齐拉西酮浓度。10位男性健康受试者进食时单剂量口服40mg盐酸齐拉西酮胶囊。于服药前及服药后0.5、1、2、3、4、5、6、8、10、12、24、36、48小时采集5m l血样。抗凝处理取血浆,-20℃保存,用于血药浓度的测定。安全性评价包括体检、实验室检查(心电图、血常规、生化常规及尿常规等)及不良事件的记录。结果主要药动学参数:Cm ax为(175.0±63.73)ng/m l;Tm ax为(3.80±1.32)h;MRT为(9.37±1.53)h;t1/2为(6.10±1.65)h;Ka为0.1831±0.0708/h;Kel为0.1219±0.0349/h;Vd为(685.3±325.4)L;C l为(83.30±34.50)L/h;AUC0→t为(1312±261.3)ng/m l/h,AUC0→∝为(1339±261.1)ng/m l/h。药物不良事件主要为嗜睡、口干、头昏、静坐不能、体位性低血压等,程度多为轻至中度,均能在短时间内缓解。结论研究结果显示了国产盐酸齐拉西酮在中国人中药代动力学特点,单剂量口服胶囊40mg是安全的。     

思瑞康与氯丙嗪治疗精神分裂症的对照研究

目的:比较思瑞康和氯丙嗪治疗精神分裂症的疗效和安全性。方法:将92例符合精神分裂症诊断标准(CCMD-3)的患者随机分为2组,每组46例,分别给予思瑞康和氯丙嗪治疗8wk,采用阳性症状与阴性症状量表(PANSS)、不良反应症状量表(TE_SS)评定疗效与不良反应。结果:思瑞康组与氯丙嗪组有效率分别为87.0%、91.3%(P>0.05)。思瑞康组嗜睡、头昏和体质量增加发生率更高(26.1%、23.9%、17.3%),氯丙嗪组锥体外副作用、心动过速和直立性虚脱发生率更高(60.9%、39.1%、32.6%)。结论:思瑞康与氯丙嗪治疗精神分裂症疗效相当,而前者不良反应相对较轻,安全性更好。     

对徒手置入胸椎椎弓根螺钉的安全性评价

目的：评价徒手置入胸椎椎弓根螺钉的安全性并探讨其置钉方法.方法：372例患者采用徒手方法置入胸椎椎弓根螺钉,记录置入操作中和术后并发症,其中37例患者术后行CT断层扫描检查判断螺钉的位置,记录所有穿透骨皮质螺钉的数目和距离.结果：共徒手置入胸椎椎弓根螺钉2261枚,平均每例患者置入螺钉6.08枚,术中6例次置钉过程中出现脑脊液从钉道中流出,术中和术后未出现神经、血管和内脏损伤等并发症.37例患者术后行CT扫描判断螺钉位置,405枚螺钉中124枚（30.62%）穿透骨皮质,1枚（0.02%）穿透椎弓根内侧壁超过4mm.结论：徒手置入胸椎椎弓根螺钉穿透骨皮质的发生率较高,应该根据每个椎体旋转、倾斜等差异个体化确定置钉位置和方向,操作仔细认真,保证准确、安全、可靠地置入胸椎椎弓根螺钉.     

Introduction of “international syringe labelling” in the Republic of Ireland

Introduction  Medication errors are a preventable cause of patient injury. In May 2003, as a result of a joint initiative by the Royal College of Anaesthetists, the Association of Anaesthetists of Great Britain and Ireland, the Intercollegiate Faculty of Accident and Emergency Medicine and the Intensive Care Society, a new colour code chart for syringe labelling was introduced. The introduction of the new system has not been uniform in the Irish Republic with no national guidelines or time scale in place. Methods  A questionnaire was administered to doctors working in Anaesthesia in two Dublin teaching hospitals. Results  As much as 23% had administered an incorrect medication and 53% admitted to a near miss as a result of the introduction of the new label. Discussion  Future action should focus on practical, common sense interventions including techniques such as those that reduce reliance on memory, standardization, the use of protocols and checklists, and the elimination of look-alike products.     

外用他克莫司和吡美莫司的安全性

他克莫司和吡美莫司是新型钙调磷酸酶抑制剂药物,其外用制剂可用于治疗特应性皮炎。近年来,对这两种药物的安全性存有争议。现有的资料表明,外用他克莫司和吡美莫司安全性高,不引起皮肤萎缩,经皮吸收极少,无明显的系统免疫抑制作用,不会引起皮肤或系统的感染和肿瘤的发病率升高。     

Safety evaluation of surgical materials by cytotoxicity testing

The cytotoxicity of three kinds of commercially available absorbable hemostats [oxidized cellulose (Surgicel, gauze and cotton types), microfibrillar collagen (Avitene), and cotton-type collagen (Integran)] and one adhesion barrier [sodium hyaluronate and carboxymethyl-cellulose membrane (Seprafilm)] were comparatively assessed by a colony assay using V79 cells and a minimum essential medium (MEM) elution assay in combination with a neutral red assay using L929 cells. Strong cytotoxicity was detected for Surgicel by both the MEM elution assay and the colony assay. For Avitene, both methods revealed weak cytotoxicity. For Seprafilm, no cytotoxicity was detected by the MEM elution assay, while a moderate degree of cytotoxicity was observed in the colony assay. For Integran cytotoxicity was not detected by either the MEM elution or the colony assay. The results of the different methods showed some inconsistency in terms of the degree of cytotoxicity of the materials. It is proposed that the combination of two or more sensitive cytotoxicity testing methods for the evaluation of biomaterials is necessary to avoid false-negative results for biomaterials at the preclinical stage. Furthermore, investigation of the correlation between the cytotoxicity and the extraction period of the surgical materials is helpful for predicting the effect of prolonged in vivo use of biomaterials on surrounding cells, tissues, and organs.