自制微铜圈栓塞兔肾动脉的效果研究

目的：探讨自制微铜圈在实验兔体内的动脉栓塞效果和生物相容性。 方法：将30只新西兰大耳白兔随机均分为实验组与对照组，分别用自制微铜圈（实验组）与Cook公司生产的微弹簧圈（对照组）经3 F微导管释放，栓塞兔肾动脉末梢支，于栓塞术后不同时间观察血管闭塞情况和病理学改变，同时对实验动物栓塞前后的实验室指标进行比较。 结果：血管造影显示，栓塞后30 min，实验组血管栓塞的效果不如对照组（P<0.05），但栓塞后3 d至12周各时间点，两组血管栓塞效果差异无统计学意义（均P>0.05）。两组栓塞后肾脏大体病理学改变相似，血栓形成情况两组间差异无统计学意义（P>0.05），但实验组血管周围炎症反应较对照组轻（P<0.05）。栓塞术后，两组肝、肾功能指标变化差异无统计学意义（均P>0.05），且均在 2周后恢复至术前水平；实验组血清铜离子术后2周内较术前升高（P<0.05），4周后恢复至术前水平（均P>0.05）。 结论：自制微铜圈与微弹簧圈在动脉栓塞效果方面相似，且具有更好的生物相容性。     

碳微粒灌注肠系膜下动脉对结肠栓塞作用的实验研究

目的 :观察医用活性碳微粒灌注肠系膜下动脉的作用效果 ,探讨行结肠癌微栓塞化疗的可能性。方法 :成年杂种犬 19只 ,分为 :①对照组 (A组 ,n =7) ,栓子为直径 (Ф) 30～ 6 0 μm的医用活性碳 (CH4 4)微粒。②单纯微栓塞组(B组 ,n =6 ) ,栓子为Ф10～ 2 0 μm的CH4 4微粒。③微栓塞化疗组 (C组 ,n =6 ) ,栓子为Ф10～ 2 0 μm的CH4 4微粒加化疗药物 (FEM)。行犬肠系膜下动脉插管 ,推注不同栓子 ,观察左半结肠和血管造影状况以及术后反应。于不同时间取组织标本 ,作光镜及透射电镜检查。结果 :推注栓子后 ,A组乙状结肠立即痉挛、苍白 ,约 30min后肠管松弛 ,刺激无反应。DSA显示动脉影僵硬迂曲、分支短少 ,肠系膜下静脉显影长达 30min以上。组织切片见栓塞段结肠壁全层彻底坏死。B、C组乙状结肠亦立即痉挛、苍白 ,但 3～ 5min后缓解 ,肠蠕动恢复。DSA显示血管痉挛较A组轻 ,但较推单纯造影剂重 ,血管显影时间分别为 930s± 192s,6 .2 5s± 1.5 2s ,(P <0 .0 1)。肠系膜下静脉显影达10min左右。犬术后一般反应及组织切片中结肠黏膜及黏膜下层细胞变性、微小灶状坏死 ,C组均较B组强。 2周后恢复正常。淋巴结、肝、肺、肾等组织中见碳栓存在。结论 :结肠可耐受一定程度的微栓塞化疗。该方法有望成为提高结肠癌     

微粒栓塞剂化疗栓塞治疗肝转移癌的疗效观察

目的 评价微粒栓塞剂化疗栓塞肝转移癌患者的临床疗效。方法 回顾性分析36例自2009年6月至2011年6月在我院应用350-560μm明胶海绵微粒化疗栓塞肝转移癌患者的临床资料,通过评价肿瘤反应、肝功能损伤、不良反应及生存率评价临床疗效。结果 中位随访时间15个月,栓塞病灶均有不同程度坏死及缩小,36例患者完全缓解(CR)：2例;部分缓解（PR）：27例;稳定（SD）：5例;进展（PD）2例;客观反应率（ORR）为80.55%;术后7天肝功能基本恢复至术前水平（p＞0.05）,无严重并发症的发生;6个月生存率91.6%、12个月生存率83.3%。结论 明胶海绵微粒化疗栓塞肝转移癌取得良好的近期疗效,远期疗效还有待于进一步观察。     

磁性微球靶向栓塞食道/胃底曲张静脉的最佳条件优选

目的 研究聚甲基丙烯酸甲酯磁性微球（简称微球）靶向栓塞食道／胃底曲张静脉的最佳条件，提高栓塞效果。方法 通过犬的脾门静脉网的靶向栓塞实验获得最佳磁场强度和最佳磁控时间；以不同粒径的微球靶向栓塞模型犬的食道／胃底曲张静脉，通过病理检查、胃镜、门脉造影评价栓塞效果，优选最佳微球粒径。结果最佳磁场强度为0．4T；最佳磁控时间为30min；最佳微球粒径是30～50μm和60～100μm。结论 以本实验所获条件进行靶向栓塞，效果最佳。     

肝动脉化疗栓塞术治疗中晚期肝癌的疗效评价

目的评价应用碘化油及四氧化三铁（Fe3O4）微球栓塞治疗原发性巨块型肝癌的临床疗效。方法回顾分析行超选择插管栓塞原发性巨块型肝癌246例,分两组,以碘化油6-27 ml＋Fe3O4250μm,丝裂霉素（10 mg）,5-Fu 250 mg混悬液栓塞,主干应用明胶海绵栓塞126例,选择同期常规剂量碘化油及明胶海绵治疗巨块型肝病120例作为对照组,碘化油用量6-27 ml,分析两组术前后病灶大小变化,近期有效率及生存率。结果碘化油及Fe3O4组近期有效率明显高于碘化油组,碘化油及Fe3O4组1、2、3年生存率分别为89.3%、42.7%、31.2%,而碘化油组分别为53.8%、14.9%、12.6%。结论碘化油及Fe3O4微球治疗巨块型肝癌较碘化油栓塞组疗效有明显提高,可视为治疗巨块型中晚期肝病的有效方法。     

不同微粒对人工关节假体周围界膜影响的实验研究

目的　观察人工关节置换中产生的磨损微粒在动物体内引起的组织学反应 ,并比较不同微粒的差异 ,探讨人工关节松动的原因。方法　成年新西兰兔 32只 ,雌雄不限。按膝关节内注入微粒的不同随机分为 4组 ,每组 8只。甲组 :注入超高分子聚乙烯微粒 ;乙组 :注入钛合金微粒 ;丙组 :注入骨水泥微粒 ;丁组 :对照组注入生理盐水。术后第 2周开始向关节囊内注入各种微粒悬液 ,每次 0 2ml,每隔两周一次直至术后 1 4周 ,在第 1 6周处死动物 ,取股骨远端及关节囊切片 ,HE染色 ,光镜观察。光镜观察关节囊滑膜的组织细胞反应、吞噬磨屑情况。从各组标本中取 0 2 g组织 ,并制成组织匀浆。离心后取上清液 ,放免法测定TNF -α含量。结果　各实验组假体隧道边缘产生一层纤维结缔组织界膜 ,其中含有大量的巨噬细胞和异物巨细胞。而对照组的假体隧道边缘未见明显的组织细胞反应。聚乙烯组、钛合金组、骨水泥组假体隧道边缘的组织细胞含量明显高于对照组 (P <0 0 5) ,而各实验组之间无明显差别。各实验组的关节滑膜细胞增生 ,滑膜下为较多的胶原纤维组织 ,并可见巨噬细胞浸润 ,纤维母细胞和毛细血管增生。而对照组的滑膜基本正常。各实验组组织中的TNF -α含量明显高于对照组(P <0 0 5)。而各实验组之间无明显差异。结论     

实验用细胞可吞噬钛微粒的制备与表征分析

目的探讨从国产工业纯钛粉中分离细胞可吞噬钛微粒的方法,为人工关节假体松动相关研究提供材料。方法将1000mg工业纯钛粉置入玻璃烧杯中,加入无水乙醇1500ml,充分搅拌混合,室温下静置后,从上层混悬液中收集钛微粒,采用粒度分析仪及扫描电镜观察钛微粒表征。结果获得的钛微粒平均粒径约为(1.169±0.484)μm,99.7%的粒径<3μm,粒径分布曲线呈正态分布;扫描电镜观察见钛微粒呈类球形,均匀,分散性好。结论无水乙醇重力液力分级法能有效地分离实验用细胞可吞噬钛微粒,其表征与国外所用相关材料相似。     

肾动脉栓塞术作为姑息疗法在中晚期肾癌治疗中的应用:附28例临床分析

目的评价肾动脉栓塞术作为姑息疗法治疗中晚期肾癌的效果。方法 2009年2月—2011年12月共28例中晚期肾癌患者在我院接受经皮肾动脉栓塞治疗,栓塞剂选用明胶海绵颗粒、弹簧圈和（或）聚乙烯醇微粒球。对其临床资料进行回顾性分析,观察肾动脉栓塞的疗效。结果对28例患者进行超选择性肾动脉栓塞,其中22例采用栓塞剂及抗癌药物栓塞,6例仅用栓塞剂进行栓塞。术后所有患者症状消失或显著减轻,无明显并发症。结论作为姑息疗法,经皮肾动脉栓塞疗法治疗中晚期肾癌安全有效。     

新型血管内栓塞材料钡铁氧化合物微粒的生物相容性

目的 探讨钡铁氧化合物(BaFe12O19)微粒作为一种新开发的新型血管内栓塞材料的生物相容性.方法 对BaFe12O19微粒进行系列生物相容性实验,包括Ames致突变实验、细胞毒性实验、全身急性和亚急性毒性实验、溶血实验、出血和凝血时间测定、凝血功能实验等.结果 BaFe12O19微粒无致突变性,无毒性,对出血和凝血时间无显著性影响,不引起溶血和凝血功能的改变.结论 BaFe12O19微粒具有良好的生物相容性.     

过滤器头皮针的研制与应用

为提高静脉推注用药的安全性 ,研制了一种孔径 3μm的过滤器头皮针 ,经微粒检测及临床应用 ,微粒 数≥10 μm为 8.73± 5 .4 8、≥ 2 5 μm为 0 .6 0± 0 .4 2 ,均低于国家标准 ,与普通头皮针比 ,差异有极显著性意义 (P <0 .0 1) ;静脉炎发生率亦显著低于对照组 (P <0 .0 1)。提示过滤器头皮针能有效阻隔药液中的微粒。     

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 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.     

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.     

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.     

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.     

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.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

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.