常压及控制性降压下脊髓急性牵拉损伤比较研究

目的 评价控制性降压是否增加脊髓对牵拉损伤的易感性。材料与方法健康成年杂种犬6只，随机分为常压和控制性降压脊髓牵拉损伤组。观察常压及控制性降压水平下相同程度牵拉损伤后脊髓血流(SCBF)、体感诱发电位(SEP)、神经源性运动诱发电位(NMEP)改变的差异。结果 外周血有创动脉压(MABP)平均下降幅度为40．5％。经SSPS统计软件独立样本t检验，不同牵拉水平下，常压组及低压组的SCBF(％)、SEP波幅(Asep)(％)及NMEP波幅(％)无显著差异。结论 尼卡地平控制性降压不增加脊髓对牵拉损伤的易感性。     

硝酸甘油、米力农和尼卡地平缓解桡动脉痉挛作用的比较

目的：比较硝酸甘油、米力农和尼卡地平3种药物对桡动脉的解痉作用。方法：收集手术后多余的人体桡动脉标本，采用器官浴槽方法，比较上述3种药物对预收缩的离体桡动脉的解痉作用。结果：米力农和硝酸甘油对预收缩的桡动脉的舒张作用明显强于尼卡地平；米力农和硝酸甘油的疗效相似。结论：米力农和硝酸甘油更适用于缓解冠状动脉旁路移植术中桡动脉的痉挛。     

Differential potentiation by calcium antagonists of neuromuscular blockade induced by pancuronium and succinylcholine in cats in vivo

Summary The effects of several calcium antagonists (verapamil, nicardipine and two diltiazem isomers, d-cis and l-cis diltiazem) alone and associated to non-depolarizing (pancuronium) and depolarizing (succinylcholine) neuromuscular blockers, were evaluated on sciatic nerve-tibialis anterior muscle preparations from cats in vivo. The calcium antagonists used (at 0.1 and 0.5mg/kg iv) did not modify the height of muscular twitches elicited indirectly. However, these agents potentiated in a dose-dependent way the neuromuscular blockade induced by iv pancuronium (2–40g/kg) and succinylcholine (6–200g/kg). The order of potency in increasing the effects of pancuronium was nicardipine d-cis diltiazem verapamil, whereas the order of potency in enhancing succinylcholine effects was d-cis diltiazem verapamil nicardipine. The effects of diltiazem were stereoselective, thus the potentiation induced by d-cis diltiazem was significantly greater in all cases than that induced by l-cis diltiazem, which suggests that calcium channel blockade plays a role in these interactions. However, other mechanisms such as calcium antagonists-induced nicotinic receptor desensitization may also be involved.     

尼卡地平和硝普钠用于颅内血管术中控制性降压的比较观察

目的：探寻颅脑术中控制性降压的理想药物。方法：选用20例22－52岁颅内动脉瘤及动静脉畸形手术病人,随机分为尼卡地平（N）组和硝普钠（S）组。观察两组降压前和降压10、20、30min及停药10、20min时的平均动脉压（MAP）,心率（HR）,颅内压（ICP）,中心静脉压（CVP）的变化,同步监测动脉及颅内静脉血气值,计算动脉氧含量（CaO2)与颈内静脉氧含量（CjO2)的差,即动静脉氧含量差值（AJDO2）和收缩压与心率乘积（RPP）。结果：两组降压均有效,与降压前比较,MAP明显下降。在控制性降压及复压过程中,N组血压变化平稳,HR、ICP和JADO2无显著变化,RPP明显下降（P＜0．01）。S组有一过性心动过速（P＜0．05）,ICP和AJDO2明显升高（P＜0．01或P＜0．05）,停药后,血压反跳（P＜0．01或P＜0．05）。结论：尼卡地平用于颅脑术中控制性降压安全有效,其临床价值优于硝普钠。     

Is conservative treatment of HELLP syndrome safe?

HELLP syndrome is associated with a high rate of maternal and perinatal morbidity and mortality, and often leads to immediate fetal extraction. However, this condition may occur very early in pregnancy and conservative approaches have been recently proposed. The limits of this approach are discussed with two cases of conservative management of HELLP syndrome complicated by abruptio placentae.     

Antioxidant effects and anti-elastase activity of the calcium antagonist nicardipine on activated human and rabbit neutrophils--a potential antiatherosclerotic property of calcium antagonists?

Activated neutrophils which produce certain proteases, such as elastase and reactive oxygen species (ROS) are involved in oxidative stress and inflammation. In the present study, we have shown that nicardipine, a calcium channel blocker, affects the release of elastase and superoxide anion radicals (O₂ ^–) in vitro during human and rabbit neutrophil respiratory bursts. The drug inhibited the release of elastase and O₂ ^– by fMLP (N-formyl-methionylleucin-phenylalaninin), calcium ionophore (A23187) and PMA (phorbol-myristate-acetate)-stimulated human and rabbit neutrophils. Besides the release of elastase, strongly inhibited in the fMLP and A23187 stimulated systems, nicardipine affected elastase and O₂ ^– in a dose-dependent manner. The corresponding 50% inhibitory concentration (IC₅₀) of nicardipine for elastase, released in PMA-stimulated human and rabbit neutrophils, was 15.95 ± 0.17 M and 18.06 ± 0.08 M, respectively, whereas for O₂ ^–, the IC₅₀ of nicardipine in PMA, fMLP and A23187-stimulated human and rabbit neutrophils was 55.41 ± 0.09 M and 58.43 ± 0.03 M, 45.21 ± 0.13 M and 37.19 ± 0.53 M, 33.54 ± 0.09 M and 30.54 ± 0.29, respectively. The mechanisms underlying the inhibition of elastase and superoxide anion radicals by nicardipine appear related to an inhibiting effect on the mobilisation of cytosolic calcium and on activation of protein kinase C (PKC). These antioxidant and anti-elastasic activities contribute to the properties of nicardipine, as positive side effects of its antihypertensive activity and may be useful to prevent inflammatory disorders (tissue damage, oxidative injury) involved in the pathogenesis of hypertension.     

尼卡地平联合多巴酚丁胺对老年慢性肺心病患者急性加重期的作用分析

目的观察尼卡地平联合多巴酚丁胺在老年慢性肺心病急性加重期的作用。方法62例肺心病急性加重期的老年患者随机分为治疗组34例和对照组28例,2组均给予常规治疗,治疗组则在此基础上给予尼卡地平和多巴酚丁胺。治疗期间观察2组症状、体征、肺动脉收缩压(PASP)、血气(PaO2、PaCO2)、心率(HR)、左室射血分数(LVEF)、右室流出道内径(RVOTD)、右心室内径(RVD)、右心肺动脉内径(RPAD)、好转时间以及不良反应,并进行比较。结果2组临床疗效比较,治疗组总有效率为88.2%,对照组总有效率为57.1%,差异有统计学意义(P<0.05);2组治疗后PASP、PaO2、PaCO2、HR、LVEF以及RVOTD、RVD、RPAD比较,治疗组较对照组有明显改善,差异均有统计学意义(P<0.05或P<0.01);2组显效时间比较,治疗组显效快,差异有统计学意义(P<0.01);2组治疗期间均未出现明显不良反应。结论尼卡地平联合多巴酚丁胺对老年慢性肺心病急性加重期作用明显,不良反应较少。