一氧化氮、一氧化氮合酶与伴精索静脉曲张不育患者精液参数的关系

目的:探讨一氧化氮(NO)、一氧化氮合酶(NOS)与伴精索静脉曲张(VC)不育患者精液参数之间的关系。方法:根据体格检查和彩色多普勒超声检查选择伴VC的不育患者(组1,n=53),其中临床型和亚临床型分别为21例和32例;同时选择非VC少弱精子症患者(组2,n=29)和正常生育者(组3,n=28)作对照组。采用硝酸还原法分别测定外周血和精浆中NO含量和NOS活性。用计算机辅助精液分析仪测定VC组患者精子密度、活动精子(a+b级精子)和快速前向运动精子百分率。结果:①组1外周血清NO含量和NOS活性与组2及组3相比差异无显著性(P>0.05),但精浆中NO含量和NOS活性组1明显高于其他两组,差异有显著性(P<0.01和P<0.05)。②组1中,随着曲张的精索静脉内径的增加,外周血清和精浆中NO含量和NOS活性均有所上升,但只有精浆中临床型和亚临床型之间相比差异有显著性(P<0.05)。③组1中,随着精子密度和精子活力的下降,外周血清和精浆中NO含量和NOS活性均有上升趋势,且精子密度≥20×106/ml和≤10×106/ml之间,精子活力≥50%和≤25%之间差异有显著性(P均<0.05)。结论:在VC诊断中精浆中NO含量和NOS活性测定较外周血清中更有意义。早期测定精浆NO含量和NOS活性对VC的诊断和治疗具有重要的临床价值。     

精浆胸苷激酶1与精液参数关系的初步分析

目的 探讨精浆胸苷激酶1(Thymidine kinase 1,TK1)的浓度与精子参数的关系.方法 利用增强化学发光法检测无精子症和少弱精子症及已生育健康人精浆TK1的浓度.同时利用计算机辅助精液分析系统分析各实验组精子密度及活力.各实验组精浆酸性磷酸酶、α-葡糖苷酶、精浆果糖和锌的浓度也一并检测.分析精浆TK1浓度变化和精子参数、精浆相关参数的相关性.结果 弱精于组(2.41±0.21)及无精子组(2.72±1.16)患者精浆TK1的浓度显著高于正常对照组(1.53±0.22)(P<0.01),少精子组(1.60±0.13)和少弱精子组(1.68±0.24)患者精浆TK1的浓度与对照组相比差异没有统计学意义(P>0.05).精浆TKl与精浆生化指标即精浆酸性磷酸酶、α-葡糖苷酶、果糖和锌的浓度都没有显著的相关性(P>0.05).结论 TKl可能与精子活动质量有一定相关性,高浓度的TKl是引起弱精子症的原因之一,与精子数量的变化关系不密切.TKI在无精子症患者中浓度偏高的原因有待进一步研究.     

精索静脉曲张不育患者精子质量及其超微结构的研究

目的:研究精索静脉曲张不育患者精液质量及精子超微结构的变化。方法:不育伴精索静脉曲张患者118例作为实验组(VC组),正常自愿捐精者76例作为对照组,对其精液常规、精浆生化及外周血内分泌水平进行检测,并应用扫描和透射电镜技术对精子的超微结构进行观察。结果:VC组精液常规检查中,精子浓度、前向运动能力、存活率显著低于正常组(P<0.05),精液量、非前向运动能力无差异(P>0.05),精浆生化各项指标中,果糖浓度无显著差异,中性α-葡糖苷酶、锌离子浓度均显著低于正常组(P<0.05),外周血FSH、LH、T、E2水平均无统计学差异(P>0.05)。扫描电镜检查示正常形态精子比率低于对照组[(56.76±15.32)%vs(12.34±6.58)%,P<0.05],精子异常主要发生在头颈部,透射电镜检查示精子畸变以尖头为主,且伴有分化异常的复杂畸形。结论:VC可导致少-弱-畸精子症,进而引起不育,其原因可能是由于精浆微环境及超微结构的改变。     

精索静脉曲张不育患者精浆α－糖苷酶的检测及其意义

对１５例正常生育男性和３８例精索静脉曲张不育男性精浆中附睾功能的特异性标记酶α－１．４－糖苷酶（α－Ｇ）活性进行测定，以探讨精索静脉曲张不育患者附睾功能有无异常以及精索静脉曲张程度、治疗效果与α－活性的关系。结果显示，精索静脉曲张不育患者α－Ｇ活性较正常人明显下降（Ｐ＜０．００１）；亚临床型以及临床各级精索静脉曲张者精浆α－Ｇ活性无差别。手术治疗病人中，精子质量无改善者精浆α－Ｇ活性较改善者降低更为明显。说明附睾功能异常及其异常程度与精索静脉曲张不育的形成和预后有一定的联系。亚临床型精索静脉曲张有必要积极治疗     

精索静脉曲张不育患者精浆α—糖苷酶的检测及其意义

对１５例正常生育男性和３８例精索静脉曲张不育男性精浆中附睾功能的特异性标记酶α－１，４－糖苷酶（ａ－Ｇ）活性进行测定，以探讨精索静脉曲张不育患者附睾功能有无异常以及精索静脉曲张程度、治疗效果与α－Ｇ活性的关系。结果显示，精索静脉曲张不育患者α－Ｇ活性较正常人明显下降（Ｐ＜０．００１）；亚临床型以及临床各级精索静脉曲张者精浆α－Ｇ活性无差别，手术治疗病人中，精子质量地无改善者精浆α－Ｇ活性较改善者降     

一氧化氮合酶对精索静脉曲张患者精子功能的影响

为探讨一氧化氮、一氧化氮合酶对精索静脉曲张（VC）患者精子功能的影响,本文测定15例VC不育患者外周静脉血清、精索静脉血清和精浆中一氧化氮（NO）及一氧化氮合酶（NOS）,并与12例有生育能力的对照组进行了对比研究。结果显示VC组精索静脉血清和精浆中NO含量及NOS活性,不仅高于其外周静脉血清（P＜0．01）,而且高于对照组（P＜0．01）,但两组外周静脉血清中两项指标无显著性差异（P＞0．05）。提示VC时可能是由于曲张精索静脉血和精浆中NOS的产生增加导致精子生成障碍或（和）精子活力下降,从而导致不育症。     

金匮肾气丸联合胰激肽原酶治疗弱精子症

目的:探讨金匮肾气丸联合胰激肽原酶治疗弱精子症的疗效及可能机制。方法:将75例弱精子症患者随机分成对照组(35例)和治疗组(40例),对照组口服Vit E胶囊,治疗组服用胰激肽原酶、金匮肾气丸;分别在治疗前和治疗3个月后检测精液量、精子浓度、前向运动精子比率、精浆超氧化物歧化酶,并观察配偶妊娠情况。结果:对照组治疗前、后的精液量为(3.15±1.13)m L、(3.68±1.24)m L,前向运动精子活动率为(26.54±4.52)%、(31.56±5.46)%,精浆SOD为(98.73±13.81)μmol/m L、(152.07±28.65)μmol/m L,组内差异具有统计学意义(P0.05);治疗组治疗前、后的精液量为(3.02±0.95)m L、(4.25±1.53)m L,精子浓度为(20.59±2.86)×106/m L、(28.97±4.25)×106/m L,前向运动精子活动率为(25.58±4.36)%、(48.76±9.38)%,精浆SOD为(102.95±12.74)μmol/m L、(203.43±37.86)μmol/m L,组内差异具有统计学意义(P0.05);且治疗组的改善程度优于对照组(P0.05)。结论:金匮肾气丸联合胰激肽原酶能显著改善弱精子症患者的精液活动率和精浆SOD,其作用机制可能是通过降低生精环境中的氧化应激损伤,改善精子活动率。     

双侧和左侧静脉结扎术治疗左侧临床型并右侧亚临床型精索静脉曲张不育患者疗效的比较

目的 探讨左侧临床型合并右侧亚临床型精索静脉曲张(Varicocele,VC)不育患者双侧精索内静脉结扎术(Bilateral Varicocelectomy,BV)是否优于单纯左侧精索内静脉结扎术(Left Varicocelectomy,LV).方法 将接受BV (n=51)和LV (n=53)的两组患者手术前后参数进行方差分析和x2检验比较.结果 两组患者术前参数有可比性(P＞0.05);术后两组患者精子参数显著改善(P＜0.05),但血清睾酮浓度和睾丸体积无显著性改变(P＞ 0.05),术后两组间参数比较差异无统计学意义(P＞0.05).结论 BV和LV两组疗效相当.     

精索静脉曲张不育患者的精浆生化分析

目的 探讨精索静脉曲张不育患者精浆中酸性磷酸酶、果糖、锌和α-糖苷酶水平的变化.方法 分别检测120例精索静脉曲张不育患者、180例非精索静脉曲张不育患者和36例正常男性的精浆中酸性磷酸酶、果糖、锌和α-糖苷酶含量.结果 精索静脉曲张不育组和非精索静脉曲张不育组精浆中酸性磷酸酶含量均显著低于正常对照组（P＜0.01）,但精索静脉曲张不育组和非精索静脉曲张不育组之间的差异无显著性意义（P＞0.05）;各组精浆果糖活性无显著性差异（P＞0.05）;精浆中锌和α-糖苷酶含量随精索静脉曲张程度的增加而降低,且明显低于正常对照组（P＜0.05）,但与非精索静脉曲张不育组之间的差异无显著性意义（P＞0.05）.结论 精索静脉曲张可通过某些因素引起精浆中酸性磷酸酶、锌和α-糖苷酶含量降低,从而造成男性不育.     

抗坏血酸盐、过氧化氢酶改善冻融人精子质量的研究

目的 探讨抗氧化剂--抗坏血酸盐、过氧化氢酶(catalase,CAT)、超氧化物歧化酶(superoxide dismutase,SOD)对冻融人精子质量的影响.方法 30份健康可生育男性精液分别添加改良人精子冷冻保护液,依所添加的抗氧化剂及终浓度分7组:未添加者为阴性对照组,余为抗坏血酸盐300、600 μmol/L组,CAT 200、400 U/ml组,SOD 200、400 U/ml组.检测各组精液冻融前后常规参数,冻融后活性氧(reactive oxidative species,ROS)水平、线粒体膜电位(△Ψm)和早期凋亡事件(Ann+PI-%、Ann-PI-%).结果 ①冻融后各组a+b级精子均比冷冻前下降(P＜0.01),但抗坏血酸盐300 μmol/L组与2种浓度的CAT组a+b级精子(43.5±10.0)%、(43.9±8.2)%、(44.3±9.4)%下降少于对照组(38.1±7.9)%,P＜0.05、P＜0.01、P＜0.01;相对应组的精子活率复苏率分别为(67.2±14.1)%、(68.4±13.8)%、(68.8±14.8)%,也高于对照组(58.8±10.1)%,P＜0.05、P＜0.01、P＜0.01;而这3组ROS水平(29.6±12.8)%、(30.0±11.2)%、(31.1±11.0)%则分别低于对照组(36.7±17.0)%,P值均＜0.05.②2种浓度CAT组的△Ψm(34.6±12.9)%、(32.9±11.2)%均高于对照组(27.5±10.8)%,P＜0.01、P＜0.05;而且低浓度抗坏血酸盐组和CAT组凋亡(Ann+PI-%)的精子(15.3±3.0)%、(15.6±2.2)%,以及未出现凋亡(Ann-PI-%)的活精子(14.0±3.8)%、(13.2±2.6)%分别低于对照组(18.1±3.9)%(P值均＜0.01)和高于对照组(10.1±4.0)%(P值均＜0.01).余实验组的检测指标与对照组相比,差异无统计学意义(P＞0.05).③冻融后各实验组a+b级精子,抗坏血酸盐600 μmol/L组、2种浓度CAT组、SOD 400 U/ml组的△Ψm,以及抗坏血酸盐组、CAT 200 U/ml组、SOD 200 U/ml组的Ann-PI-%均分别与对应组的ROS水平呈负相关;而抗坏血酸盐组、CAT 200 U/ml组的Ann+PI-%则与对应组的ROS水平呈正相关,P＜0.05或P＜0.01.结论 在精液冷冻保护剂中添加一定浓度的抗坏血酸盐、CAT可改善冻融人精子质量.     

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.     

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.     

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.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.