浅低温心脏不停搏心内手术对心肌保护效果的比较

目的:探讨浅低温体外循环(CPB)心脏搏动中心内直视手术对心肌保护的效果.方法:40例患者随机分为观察组(浅低温心不停搏组)和对照组(中低温心停搏组).分别在术前、转机、停机及术后6 h、12 h、24 h、48 h、72 h,取冠状静脉窦或中心静脉血样,测定血气分析及血清中肌酸磷酸激酶(CK)及其同功酶(CK-MB)、天门冬氨酸氨基转换酶(AST)、乳酸脱氢酶(LDH)、丙二醛(MDA)、超氧化物歧化酶(SOD)的含量.并取心房间隔肌观察心肌含水量及心肌超微结构的改变.临床观察CPB时间、脱机、呼吸支持、多巴胺应用、严重心律失常和血红蛋白尿等指标.结果:冠脉循环血气、电解质、酸碱水平与体循环的组内组间对比基本一致.CK、CK-MB、AST、LDH两组在CPB和术后均有增加,且以对照组升高显著,与观察组相同时点相比,差异均有显著性(P＜0.01).对照组术后MDA明显升高,SOD明显降低(P＜0.01),而观察组变化不大.心肌含水量和超微结构观察,对照组变化显著,而观察组轻微改变.临床指标观察,观察组优于对照组.结论:浅低温体外循环心脏不停搏心内直视手术对心肌损伤很轻,有很好的心肌保护效果.     

Investigation of Role of Nitric Oxide in Protection from Bordetella pertussis Respiratory Challenge

The mechanism whereby whole-cell pertussis vaccines (WCV) confer protection against Bordetella pertussis is still not fully understood. We have previously reported that macrophage activation produced by vaccination with WCV is associated with induction of NO synthesis by macrophages in response to in vitro stimulation with B. pertussis antigens. To determine whether NO production is an effector of protection or simply a marker of activation, the susceptibility of inducible nitric oxide synthase (type II, iNOS) knockout mice to infection with B. pertussis was examined. We showed that iNOS knockout mice were more susceptible to B. pertussis respiratory challenge than wild-type mice. iNOS-deficient mice also developed a less effective protective response than wild-type mice after the same immunization with WCV. This suggests that NO plays an important role in effecting protection against B. pertussis challenge.     

Reflex Cardiorespiratory Effects of Nociceptive Oesophageal Distension in the Decerebrate Rat

It is well established that painful distension of hollow viscera such as the oesophagus can evoke a reflex tachycardia and pressor response; however, the nature of the oesophageal afferent pathway(s) remains controversial. This study investigated the afferent arc which mediates these reflex cardiovascular changes in the decerebrate rat. In addition, the effect of oesophageal distension on the respiratory activity of the costal diaphragm was studied. Focal distension of the oesophagus (volume of 0.3 ml applied for 10 s) just above the diaphragmatic hiatus evoked a reproducible pressor response and tachycardia in the decerebrate rat. Respiration was transiently inhibited at the beginning of oesophageal distension and prior to the rise in blood pressure. Neuromuscular blockade with the nicotinic acetylcholine receptor blocker alpha-bungarotoxin (140 microg bolus) had no effect on the magnitude of the cardiovascular response. Therefore the efferent supply to the striated muscle of the rat oesophagus was not essential in mediating this reflex. Signal averaging of the mean blood pressure response showed that neither selective ablation of oesophageal spinal afferents nor bilateral vagotomy altered the early trajectory of the pressure response. Bilateral vagotomy reduced the peak magnitude of the response to sustained oesophageal distension. In contrast, selective removal of spinal afferents had no effect on the response. Ablation of both neural pathways was essential to abolish the reflex cardiovascular and respiratory responses. It can be concluded that both vagal and spinal afferent pathways are utilised in the reflex cardiorespiratory response to painful oesophageal distension. Although ablation of one neural pathway had no effect on the response it was still implicated in the reflex, since ablation of both pathways was necessary to prevent the cardiorespiratory changes. This study emphasises the need for caution when inferences are made concerning single selective ablations of multiply innervated organs.     

小儿心包积液28例临床分析

目的：探讨小儿心包积液的病因、分类及诊断。方法：病例回顾性分析。结果：28例中，化脓性心包积液4例，结缔组织疾病所致心包积液16例，肾病综合征所致心包答液4例，病毒性、肺吸虫性、幼年型粘液性水肿及肿瘤性心包积液各1例。治愈、好转25例，另3例，分别死于急性心包填塞，风湿性全心炎、心功能不全、呼衰、纵隔肿瘤广泛转移。结论：小儿心包积液，可由多种致病因素引起。其临床特点，对该病的诊治有重要意义。     

Reversal of ischemic liver failure by intrasplenic liver cell transplantation

A model of ischemic hepatic failure in Sprague-Dawley rats (SD) with 100% mortality has been developed by one-hour occlusion of the right portal vein and hepatic artery followed by left 70% hepatectomy. The intrasplenic injection of 40 x 10(6) syngeneic adult or three-day neonatal single liver cell suspensions decreased the mortality from 100% to 50% and 36%, respectively. Mortality decreased with increasing time from the intrasplenic injection of neonatal liver cells to the time of acute hepatic ischemia. Mortality also decreased with increasing interval between hepatic ischemia and removal of the transplanted liver cells by splenectomy. Intrasplenic injection of graded doses of neonatal liver cells decreased mortality from 75% at a dose of 10 x 10(6) cells, to 36% at 160 x 10(6) cells. Treatment of neonatal liver cells with metabolic inhibitors did not significantly affect their ability to reverse acute hepatic ischemia.