凋亡抑制基因Bcl-2蛋白产物在沙土鼠海马缺血耐受中的表达

目的 研究沙土鼠短暂的脑缺血后海马ＣＡ１区Ｂｃｌ－２蛋白的表达,探讨Ｂｃｌ－２蛋白表达与脑缺血耐受之间的关系,方法 采用夹闭沙土鼠双侧颈总动脉造成脑缺血模型。６３只健康沙土鼠随机分成四组。非缺血对照组（Ａ组,ｎ＝５）;预处理对照组（Ｂ组,ｎ＝６）,单次脑缺血２ｍｉｎ;缺血预处理组（ＰＣ组,ｎ＝２６）与缺血对照组（ＩＲ组,ｎ＝２６）,有或无预处理缺血２ｍｉｎ,间隔３ｄ后缺血５ｍｉｎ,分别再灌４ｈ（Ｐ     

利多卡因对短暂脑缺血后海马区细胞凋亡的影响

目的 探讨利多卡因对短暂脑缺血后海马区迟发性神经元降解的影响。方法 脑缺血模型为兔脑四血管夹闭模型,２５只家兔随机分成三组：假手术组（Ｓｈ,ｎ＝５）;缺血组（Ｉｓ,ｎ＝１０）,夹闭双侧颈总动脉和椎动脉５ｍｉｎ后恢复脑灌注;利多卡因组（Ｌｉ,ｎ＝１０）,夹闭颈总和椎动脉前５ｍｉｎ给予利多卡因１０ｍｇ／ｋｇ。３组均于３ｄ后取脑行病理ＨＥ染色和ＴＵＮＥＬ染色,对民区阳性细胞进行计数。结果 ＨＥ染色发生缺     

大鼠全脑缺血再灌注细胞凋亡的观察

本实验采用大鼠全脑缺血再灌注模型，观察缺血后不同时间点的神经元凋亡，以研究大鼠全脑缺血再灌注后脑组织的形态学改变。材料与方法一、动物分组健康、雄性Ｗｉｓｔａｒ大鼠４３只，体重２００～２５０ｇ，随机分成七组；假手术组（Ａ组，ｎ＝５），缺血组：分成缺血１０分钟组Ｂ组、缺血６小时组Ｃ组（各组ｎ＝５），缺血再灌注组：缺血１０分钟再灌注１天组Ｄ组、２天组Ｅ组、４天组Ｆ组、７天组Ｇ组（各组ｎ＝７）。二、脑缺血模型的制备采用Ｐｕｌｓｉｎｅｌｌｉ法［１］，制备大鼠全脑缺血模型。假手术组只分离出翼小孔、双侧颈总动…     

不同缺血方式对大鼠肾脏损伤作用的实验研究

目的 研究在总缺血时间一定的情况下不同缺血方式对肾脏的损伤程度及其作用机理。方法 ４５只Ｗｉｓｔａｒ大鼠制备成肾缺血动物模型。Ａ组为正常对照组（ｎ＝１０）;Ｂ组为持续缺血组（ｎ＝１０）;Ｃ组为间断缺血组（ｎ＝１０）;Ｄ组为缺血预处理组（ｎ＝１０）;Ｅ组为缺血预处理延迟效应组（ｎ＝５）。手术后动态观察各组动物肾功能改变、组织学以及肾组织再灌注前后ＭＤＡ含量变化。结果 （１）Ｃ组术后肾功能各项指标与Ａ     

心跳骤停期间及心肺复苏前后前脑M受体变化的实验研究

目的 探讨心跳聚停（ＣＡ）期间及心肺复苏（ＣＰＲ）前后前脑Ｍ受体变化的规律。方法 采用窒息致大鼠ＣＡ的动物模型,５５只Ｗｉｓｔａｒ大鼠随发为正常对照组（ｎ＝８）、手术对照组（ｎ＝７）、ＣＡ１组（ｎ＝８）;窒息１０ｍｉｎ,ＣＡ２组（ｎ＝８）;窒息３０ｍｉｎ,以及ＣＰＲ前组（ｎ＝８）;窒息１０ｍｉｎ和ＣＰＲ后组（ｎ＝９）：窒息１０ｍｉｎ后复苏,自主循环恢复后继续机械通气３０ｍｉｎ,实验结束时断头取脑,     

异氟醚对外周伤害性刺激大鼠模型脊髓c-fos表达的影响

目的 观察异氟醚对外周伤害性刺激大鼠模型脊髓ｃ－ｆｏｓ表达的影响,初步探讨异氟醚在脊髓的可能作用部位。方法 ＳＤ大鼠６０只随机分为３组。于大鼠左后掌心皮下注射５％,损尔马林１５０μＩ建立外周伤害性刺激模型。Ａ组（伤害性刺激组,ｎ＝２５）,Ｂ组（异氟醚组,ｎ＝２５）,在建立模型前１０ｍｉｎ开始吸入１．５ＭＡＣ异醚。Ａ、Ｂ 按刺激模型建立的时间（０ｈ,０．５ｈ,１ｈ,２ｈ,３ｈ）模型前１０ｍｉｎ开始吸     

浅低温以犬全脑缺血再灌注后脑组织诱导型热休克蛋白70表…

目的：研究犬全脑缺血再灌时浅低温对热休克蛋白７０（ＨＳＰ７０）表达的影响，探讨热休克蛋白在低温脑复苏中的作用。方法：采用犬心脏停跳再复苏模型。１４只犬随机分为三组：非缺血对照组（ｎ＝４）、常规治疗组（ｎ＝５）和浅低温组（ｎ＝５）。用免疫组化测定脑组织内ＨＳＰ７０表达阳性细胞数密度和反应产物灰度值。结果：犬全脑缺血再灌后ＨＳＰ７０表达明显增强（Ｐ〈０．０１）．浅低温组ＨＳＰ７０表达增强比常规治疗组更     

七氟醚肝毒性研究的初步报告

为研究不同吸入浓度七氟醚对肝脏的影响，４０只ＳＤ大鼠被随机分为四组，对照组（Ｉ组，ｎ＝１０，０ＭＡＣ）；异氟醚组（Ⅱ组，ｎ＝１０，０．５ＭＡＣ）；０．５ＭＡＣ七氟醚组（Ⅲ，组，ｎ＝１０，０．５ＭＡＣ）；０．９ＭＡＣ七氟醚组（Ⅲ２组，ｎ＝１０，０．９ＭＡＣ）。各组动物分别吸相应浓度麻醉药，３ｈ／ｄ，共６ｄ，以肝功能变化，肝组织细胞这改变作为评价肝脏受损指标，结果提示，七氟醚对肝脏有一定的影响，与异氟     

七氟醚及其它挥发性麻醉药对肝药酶的影响

目的：观察七氟醚及其它挥发性麻醉药对肝药酶的影响。方法：将４０只月龄２～３月的ＳＤ大鼠随机分：对照组（Ｃ组，ｎ＝１０，０ＭＡＣ）、氟烷组（Ｆ组，ｎ＝１０，０．５ＭＡＣ）、异氟醚组（Ｉ组，ｎ＝１０，０．５ＭＡＣ）和七氟醚组（Ｓ组，ｎ＝１０，０．５ＭＡＣ）。各组动物分别吸入相应浓度的麻醉药，３小时／天，共７天。结果：表现为Ｆ组及Ｓ组肝脏代谢戊巴比妥钠的能力明显高于对照组（Ｐ＜０．０１）；Ｉ组有高于对照组的倾向（Ｐ＞０．０５）。结论：七氟醚、氟烷和异氟醚有酶诱导作用或倾向。     

浅低温对犬心脏停跳复苏后脑线粒体膜流动性及Na^＋—K^＋ATPa …

目的 研究全脑缺血再灌注损伤后脑线体膜流动性及Ｎａ＾＋－Ｋ＾＋ＡＴＰａｓｅ的变化及低温的影响。方法 健康家犬１６只随机分为三组：Ａ组（ｎ＝４），非缺血对照组，Ｂ组（ｎ＝６）?心脏停跳复苏后常温常规组；Ｃ组（ｎ＝６），心脏骤停复苏后，低温液灌注组。Ｂ、Ｃ两组动物心脏停跳１８分钟复苏后治疗观察８小时，Ａ组动物完成手术操作观察８小时，处死动物取脑组织测定线粒体膜浒性。Ｎａ＾＋－Ｋ＾＋ＡＴＰａｓｅ活性和Ｍ     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

A comparison of the inhibitory effects of four volatile anaesthetics on the metabolism of chlorzoxazone, a substrate for CYP2E1, in rabbits

Background: Halothane inhibits in vitro and in vivo activity of cytochrome P-450 (CYP) 2E1. There are several fluorinated volatile anaesthetics besides halothane, and most of them are defluorinated by CYP2E1. It is unclear whether other fluorinated anaesthetics inhibit the in vivo activity of CYP2E1.
Methods: We compared the inhibitory effects of therapeutic concentrations of four inhalational anaesthetics, halothane, enflurane, isoflurane, and sevoflurane, on chlorzoxazone metabolism in rabbits receiving artificial ventilation.
Results: All four inhalational anaesthetics decreased arterial blood pressure and increased plasma chlorzoxazone concentration. However, no significant differences in the plasma chlorzoxazone concentration were found between the four anaesthetics. The estimated chlorzoxazone clearance increased after beginning inhalation with all four agents, but no significant difference in clearance was noted between agents.
Conclusions: At therapeutic concentrations, the in vivo inhibitory effect on chlorzoxazone metabolism was similar for all four inhalational anaesthetics examined, even though their chemical characteristics and extent of hepatic metabolism differ considerably.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

Synergistic interaction between the effects of propofol and midazolam with fentanyl on phrenic nerve activity in rabbits

Background: It has been shown that the depressive effects of both propofol and midazolam on consciousness are synergistic with opioids, but the nature of their interactions on other physiological systems, e. g. respiration, has not been fully investigated. The present study examined the effect of propofol and midazolam alone and in combination with fentanyl on phrenic nerve activity (PNA) and whether such interactions are additive or synergistic. Methods: PNA was recorded in 27 anaesthetised and artificially ventilated rabbits. In three groups, propofol, fentanyl and midazolam were administered intravenously in incremental doses to construct dose-response curves for the depressant effects of each one on PNA. In another two groups, the effect of pretreatment with either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. on the effects of propofol and fentanyl respectively on PNA were studied. Results: Propofol and fentanyl caused a dose-dependent depression of PNA with complete abolition at the highest total doses of 16 mg · kg^?1 i. v. and 32 μg · kg^?1 i. v., respectively. In contrast, midazolam in incremental doses to a total of 0.8 mg · kg^?1 reduced mean PNA by 63%, but approximately 12% of PNA remained at a total dose as high as 6.4 mg · kg^?1. The mean ED₅₀s, calculated from dose-response curves, were 5.4 mg · kg^?1, 3.9 μg · kg^?1 and 0.4 mg · kg^?1 for propofol, fentanyl and midazolam, respectively. Initial doses of either fentanyl 1 μg · kg^?1 i. v. or midazolam 0.05 mg · kg^?1 i. v. acted synergistically with subsequent doses of either propofol or fentanyl to abolish PNA at total doses of 8 mg · kg^?1 and 8 μg · kg^?1, respectively. Conclusion: Fentanyl has a synergistic interaction with both propofol and midazolam on PNA and hence potentially on respiration.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.     

Systemic analgesia adapted to the children's condition

A concept of balanced analgesia using nonsteroidal anti-inflammatory drugs (NSAIDs), paracetamol (acetaminophen), opioids, and corticosteroids can also be used in patients with pre-existing illnesses. NSAIDs are the most effective treatment for acute pain of moderate intensity in children; however, these drugs should be avoided in patients at increased risk for serious side effects, e.g. patients with renal impairment, bleeding tendency, or extreme prematurity. NSAIDs can be given with minimal risks to the younger child with mild to moderate asthma, and, in these patients, the use of steroids can be encouraged; in addition to their antiemetic and analgesic action, a beneficial effect on asthma symptoms can be expected. In the non-intubated child with cerebral trauma, exaggerated sedation caused by opioids and increased bleeding tendency caused by NSAIDs must be avoided. In neonates and small infants, the oral administration of sucrose or glucose is helpful to minimize pain reaction during short uncomfortable interventions.