一种新的单侧听觉气传导持续阻滞大鼠模型

用外耳道外沿皮下缝合法制备了一种新的单侧听觉气传导持续阻滞大鼠模型。它具有制作简便、损伤较小、效果持续的优点。     

A Comparative Study of the Percutaneous versus Intraoral Technique for Mental Nerve Block

Objective: Mental nerve block is frequently used to aid repair of facial lacerations; both percutaneous and intraoral approaches to blocking this nerve are used, but have never been compared. The authors compared the two techniques for pain of administration and effectiveness of anesthesia. Methods: A prospective, randomized, single-blind, crossover study was conducted using ten healthy volunteers aged 22 to 33 years. Patients having prior experience with mental nerve blocks, lidocaine allergy, active oral/facial infection, or previous facial fractures were excluded. Bilateral mental nerve blocks were done using intraoral technique on one side and percutaneous technique on the other. Both techniques were used by the same investigator and were carried out with 27-gauge needles and 2.5 mL of 2% buffered lidocaine at room temperature injected over 20 seconds. The oral mucosa was topically anesthetized with viscous lidocaine for 1 minute prior to intraoral injection. The orders of the blocks and sides of the face anesthetized were randomized. Subjective and objective pain (visual-analog scale), efficacy (anesthesia of lower lip), time to onset, and duration of anesthesia were evaluated. Results: The intraoral technique was subjectively less painful than the percutaneous approach in nine of ten subjects (p = 0.02). Scores on the visual-analog pain scale were significantly lower for the intraoral technique (p = 0.03). Intraoral injection produced lower-lip anesthesia in 10/10 subjects versus 7/10 for percutaneous (p = 0.25). Times to onset (approximately 1–2 minutes) and durations of anesthesia (approximately one hour) were similar for the two techniques. Conclusion: The intraoral approach to the mental nerve block with adjunctive topical anesthesia was subjectively and objectively less painful than the percutaneous approach without adjunctive anesthesia. While the intraoral approach had a greater efficacy of lower-lip anesthesia and a longer duration of action, these differences were not statistically significant.     

Complications associated with maxillary nerve block anaesthesia via the greater palatine canal

This paper documents the type, frequency and duration of complications associated with regional anaesthesia of the maxillary nerve via the greater palatine canal in a series of 101 patients treated in the Oral Surgery Department, United Dental Hospital of Sydney.     

硬膜外阻滞对高血压患者血压的影响

目的:比较未经正规治疗的高血压患者中位和低位硬膜外阻滞时对血压的影响。方法:有明确的高血压病史的急诊中上腹部手术麻醉病例42例(Ⅰ组)和下腹部手术麻醉病例47例(Ⅱ组),采用硬膜外阻滞后,比较手术时间、局麻药总量、麻醉后动脉血压下降的幅度和时相。结果:(Ⅰ组)手术历时62.3±17.8min,局麻药总量为利多卡因387.0±31.2mg,(Ⅱ组)手术历时56.8±14.9min,利多卡因总量366.7±30.1mg,均无显著差异。Ⅰ组硬膜外麻醉前平均动脉压为123.6±13.2mmHg,麻醉后最低的平均动脉压为69.5±10.0mmHg,出现最低平均动脉压的中位时间为26.3min,Ⅱ组麻醉前的平均动脉压为117.3±15.7mmHg,麻醉后最低平均动脉压为71.0±7.4mmHg,出现最低平均动脉压的中位时间为21.3min。两组在硬膜外阻滞后平均动脉压下降幅度及下降时间方面无显著差异。结论:未经很好控制的高血压患者硬膜外阻滞后均可引起血压急骤下降,低位硬膜外阻滞与中高位阻滞引起的血压下降幅度和时相相似。     

Cobalt-dependent potentiation of net inward current density in Helix aspersa neurons.

A low concentration of transition metal ions Co2+ and Ni2+ increases the inward current density in neurons from the land snail Helix aspersa. The currents were measured using a single electrode voltage-clamp/internal perfusion method under conditions in which the external Na+ was replaced by Tris+, the predominant external current carrying cation was Ca2+, and the internal perfusate contained 120 mM Cs+/0 K+; 30 mM tetraethylammonium (TEA) was added externally to block K+ current. In the presence of Co2+ (3 mM) or Ni2+ (0.5 mM) inward Ca2+ currents were stimulated normally by voltage-dependent activation of Ca2+ channels. There was a 5-10% decrease in the rate of rise of the inward current. The principal effect of Co2+ and Ni2+ in increasing the current density seems to be a decrease in the rate at which the inward currents decline during a depolarizing voltage pulse. The results may be due to a decrease in a voltage-dependent or Ca(2+)-dependent outward current and/or an inhibition of Ca2+ channel inactivation. Outward current under these conditions (zero internal K+) was significant and most likely due to Cs+ efflux through the voltage-activated or Ca(2+)-activated nonspecific cation channels. Co2+ is an extremely effective blocker of this outward current. These results are not an artifact of internal perfusion or the special ionic conditions. Intracellular recording of unperfused neurons in normal Helix Ringer's solution showed that the Ca(2+)-dependent action potential duration was increased significantly by low concentrations of Co2+. This result is consistant with the Co(2+)-dependent increase in inward (depolarizing) current seen in voltage-clamp experiments.     

Ethylene vinylacetate copolymer particles dissolved in polyvinyl alcohol (2,000-mer) solution as an embolic material for vascular anomalies

We have prepared a new material for embolisation: ethylene vinylacetate copolymer dissolved in polyvinyl alcohol. When in contact with blood, polyvinyl alcohol rapidly becomes a soft gel, which is accompanied by wedging of the ethylene vinylacetate copolymer. We analysed the histopathology of intra-arterial microemboli in rats, after intracarotid injection of this material. We confirmed that it was applicable to embolisation for neurosurgical treatment.     

Intra-Hisian Block Associated with Unusual Etiologies

One hundred and sixty-nine patients underwent electrophysiologic study for atrioventricular block. Forty-five (27%) had intra-Hisian block. Four of these 45 patients had unusual etiologies: rheumatoid arthritis, cysticercosis cellulosae, Behcet's disease, and Takayasu aorto-arteritis. Their clinical and electrophysiologic features are described in detail.     

神经电生理检测对多灶性运动神经病诊断价值的初步研究

目的 探讨神经电生理检查在多灶性运动神经病(MMN)中的诊断价值。方法对16例MMN患者及16名健康对照进行运动神经传导速度和感觉神经传导速度检查，记录刺激引出的复合肌肉动作电位的波幅、波宽、面积、位相和时限，进行对比分析，判定是否有运动神经传导阻滞(CB)或暂时性离散(TD)，并有选择性地进行常规肌电图检查。结果16例患者均可见有一根以上运动神经或至少一根运动神经的一个以上部位出现CB或CD。其中13例双上肢正中神经，尺神经出现CB，3例以正中神经、尺神经的远端出现CB首发，随病情进展出现下肢腓深神经CB。仅有2例感觉神经传导速度稍有减慢，波幅略有降低。16例患者神经受累区域以下所支配肌肉肌电图检查见有神经源性损害。结论MMN是一种以远端神经受累为主的不对称性周围神经病，神经电生理检查对诊断和鉴别诊断．MMN起重要作用，CB是MMN的主要神经电生理表现。     

选择性上肢神经阻滞和静脉局部麻醉的进展

临床实践中，尽管臂丛神经阻滞可采用多种人路以满足上肢区域麻醉的需要，但有时仍需应用一些不常见的技术，如选择性上肢神经阻滞和静脉局部麻醉（IVRA），来阻滞非源自臂丛的神经或弥补臂丛神经阻滞不全。