胃肠道类癌的诊断及外科治疗

类癌这一名词诞生于本世纪初，1907年Obern－dorfer用“karzinoid”来描述一组生长缓慢、低度恶性的肿瘤，随后发现这类肿瘤来源于消化道具有嗜银特性的Lieberkuhn肠腺。1953年Lembeck发现这类肿瘤细胞可以分泌卜羟色胺，1969年Pearse发现该类细胞具有摄取胺前体和脱羧基的作用，随后，由于免疫组织化学技术的发展及应用，人们发现类癌细胞可以产生许多肽类和胶类的激素物质，因此，人们对类癌的命名和归类提出了质疑。在1980年世界卫生组织的分类中，人们将许多神经内分泌系统的肿后统称为“类癌”，但其中不包括胰岛细胞瘤．甲状腺出样…     

中分子物质的研究进展

中分子物质是一定分子量范围内的混合物总称，是具有一定化学结构和生化特性的肽类。本文就近年来对中分子物质的研究动态及休克领域中的研究进展加以综述，并就其在麻醉学领域研究的应用提出展望。     

PS-SOD脂质体对乳猪体外循环肺保护作用的研究

目的 探讨肺表面活性物质-超氧化物岐化酶（黔SOD）脂质体在乳猪体外循环中的肺保护作用。方法 选用2-3周龄乳猪30头，随机分为对照组、PS组、SOD组、PS＋SOD组、PS-SOD脂质体组5组。常规建体外循环，转流150min，主动脉阻断60min。分别在气管插管后、主动脉开放前2个时点经气管插管向肺内均匀注入生理盐水、PS、SOD、PS＋SOD、PS-SOD脂质体。于术前、术毕、术后2,6和12h5个时点检测乳猪肺顺应性（Cdyn）、氧合指数。测定术后肺组织中丙二醛（MDA）、髓过氧化物酶（MPO）、谷胱甘肽过氧化物酶（CSH-PX）的含量，并行肺组织形态学观察。结果 PS-SOD脂质体组术后Cdyn与PS组及PS＋SOD组比较无明显改变（P〉0．05），与SOD组比较明显改善（P〈0．05）。与术前比较，PS组SOD组和PS＋SOD组氧合指数均明显下降且回升不明显，而PS-SOD组下降不明显且术后迅速回升。PS＋SOD组与SOD组比较，MPO、MDA无明显下降，GSH-PX无明显升高（P〉0．05）。PS-SOD脂质体组与SOD、PS＋SOD组比较，MPO、MDA明显下降，GSH-PX明显升高（P〈0．01）。PS＋SOD组肺病理形态学定量评估与PS组及SOD组比较无明显减轻（P〉0．05）。PS-SOD脂质体组肺病理形态学定量评估与PS、SOD、PS＋SOD相比较则明显减轻（P〈0．05）。结论 单纯应用PS或SOD均有一定的肺保护作用，但二者混合应用并未提高作用效果，PS-SOD脂质体表现出更良好的肺保护效应。     

与蛋白的亲密接触

美丽小贴士酶:是由活细胞产生的具有催化功能的蛋白质,超氧化物歧化酶(SOD)是我们最熟悉的一种酶。随着年龄的增长由于体内缺乏SOD,皮肤的老化过程会加速、色素会沉着。丝素蛋白:可促进体内细胞的新陈代谢,保持皮肤弹性,具有良好的保湿作用。免疫因子:是人体重要的免疫调节物质,缺乏时可直接导致人体免疫力下降,诱发各种疾病。生长因子:有EGF、bFGF、aFGF等可加快伤口愈合促进细胞再生的功能。     

葛根素对糖尿病足患者血管活性物质平衡的影响

目的：探讨葛根素对糖尿病足（DF）患者内皮细胞功能及其血管活性物质平衡关系的影响。方法：应用葛根素治疗糖尿病足,对患者治疗前后血浆ET、CGRP、SOD、LPO、TXB2和6－K－PGI2进行检测及其疗效评定。结果：DF患者治疗前ET、LPO、TXB2明显增高,CGRP、SOD、6－K－PGI2明显降低。经葛根素治疗后以上指标均有改善,但以ET、LPO、TXB2显著性降低为主。结论：葛根素具有抑制ET、LPO和TXB2的分泌,增加CGRP、SOD、6－K－PGI2的含量,调节血管舒缩功能平衡的作用。     

正常小鼠小肠类器官体外培养体系的建立与功能鉴定

目的建立正常小鼠小肠类器官体外培养体系并进行功能鉴定, 为慢性肾脏病下肠道的物质转运提供体外研究工具。方法分离提取C57BL/6J小鼠小肠隐窝, 于体外三维培养体系中培养, 倒置显微镜下观察小肠类器官的形成过程, 苏木精-伊红染色观察小肠类器官的组织结构, 免疫荧光鉴定小肠类器官的细胞构成, 实时荧光定量PCR检测小肠类器官中物质吸收相关转运体的表达。结果成功提取小肠隐窝, 并顺利构建小肠及不同肠段类器官, 所培养的类器官具有旺盛的增殖能力, 传代后仍能维持增殖状态。免疫荧光结果显示小肠类器官表达黏蛋白2、嗜铬粒蛋白A、Oflm4及溶菌酶不同类型肠道细胞标志物。实时荧光定量PCR结果显示小肠类器官表达钙盐、磷酸盐、钠盐吸收相关转运体, 且不同肠段类器官钠盐及磷酸盐吸收主要转运体mRNA表达水平与体内一致, 符合小肠节段性吸收的特点。结论成功构建小肠及不同肠段类器官, 首次观察到类器官中物质吸收相关转运体的表达, 为慢性肾脏病下开展肠道物质转运体外研究提供了稳定和便利的工具。     

超氧化物歧化酶在男性不育症检测中的意义

超氧化物歧化酶（superoxidedismutase，SOD）是一种有效的氧自由基清除剂，能催化O2;生成H2O2和O2的歧化反应，在防御氧的毒性、抗辐射损伤及预防衰老等方面具有重要作用。在人精液中也含有大量SOD，其活性是人血浆的20倍[1]。精液中SOD能够抑制人精子脂质过氧化，减少因脂质过氧化而造成精于活力丧失，对抗超氧离子介导的组织损伤，对精子具有保护作用;另一方面，与正常的SOD保护性作用相矛盾的是，过高的S（）D活性又与精子功能损伤有关”，”，这样使得精液中S（）D作用变得复杂起来。本文通过对不同原因不育病人的S（）D活性…     

乌头类生物碱在体外循环心内直视手术中心肌保护作用及其机制

目的探讨乌头类生物碱在体外循环心内直视手术中抗心肌缺血再灌注损伤作用及其机制。方法将患者随机分成对照组和乌头类生物碱组。于开放主动脉时、体外循环结束时、手术结束时、术后1d等各个时间点测两组患者血清肌酸激酶同工酶(CKMB)、肌钙蛋白(cTnI)、超氧化物歧化酶(SOD)、丙二醛(MDA)含量;于停机时测心肌组织SOD、MDA含量。结果乌头类生物碱组CKMB水平分别为21.63±4.54,29.73±6.53,37.78±6.55,28.74±7.16,与对照组比较差异有统计学意义(P<0.05);cTnI值分别为0.337±0.141,0.497±0.271,0.758±0.399,0.542±0.244,与对照组比较差异有统计学意义(P<0.05);SOD值分别为75.56±20.09,77.01±20.36,91.39±19.56,108.44±24.23,与对照组比较差异有统计学意义(P<0.05);MDA水平分别为4.14±1.88,7.48±2.97,7.86±3.44,6.79±3.21,6.16±3.30,与对照组比较差异有统计学意义(P<0.05)。术后乌头类生物碱组心肌组织MDA值明显低于对照组(P<0.05),而SOD值则明显高于对照组(P<0.05)。结论乌头类生物碱对体外循环心肌缺血再灌注损伤具有保护作用。     

雌激素抗氧化作用与绝经后骨质疏松症的关系

目的探讨活性氧与雌激素的相关性，以进一步阐明活性氧与骨质疏松症的内在联系。方法本研究选择符合纳入标准的绝经后妇女，测定其骨密度（BMD），根据骨密度分为骨质疏松组、骨量减少组及正常组各30例。检测各组研究对象的血清丙二醛（MDA）、超氧化物歧化酶（SOD）及雌二醇（E2），比较各组之间的MDA、SOD及E2的不同并分析MDA、SOD与E2的相关性。结果MDA与E2呈显著负相关（r=-0．458，P〈0．01），SOD与E2呈显著正相关（r=0．527，P〈0．01）；骨质疏松组的MDA较骨量减少组及正常组升高而SOD含量降低（P〈0．01）。骨质疏松组的E2较骨量减少组及正常组降低（P〈0．01）。结论绝经后妇女体内活性氧水平与雌激素的变化密切相关，雌激素具有抗氧化作用，雌激素水平降低引起的绝经后骨质疏松症，可能包含了活性氧的参与和介导。     

香熏法／淋巴引流术对SOD、MDA影响的临床观察

目的：观察香熏法／淋巴引流沭对人体血清中超氧化物歧化酶（Superoxide dimutase，SOD）活力和丙二醛（mal ondialdehyde，MDA）含量的影响。方法：采用随机单盲法将就医者分为空白组、中医经穴推拿组（对照组）和香熏法／淋巴引流术组（实验组），每组各30例，共90例。除空白组外，对照组用甜杏仁载体油进行面部肌肉推．按手法和点按承浆、地仓、颊车、下关、睛明等穴位按摩，背部进行肌肉推．按手法和点按背俞穴等穴位按摩；香熏法／淋巴引流术组用甜杏仁载体油进行面部和背部按摩（同对照组），配合淋巴引流术按摩（往淋巴结方向做缓慢的波浪式推动），以上两组每周治疗2次，共2周，90min／次，实验前后各抽2mr血液检测血清中SOD活力和MDA含量。结果：实验前，三组的SOD活力、MDA含量相比，P〉0．05；实验后：①实验组与对照组SOD活力、MDA含量相比，P〈0．01；②实验组与空白组SOD活力、MDA含量相比，P〈0．01；③对照组与空白组SOD活力、MDA含量相比，P〉0．05。结论：香熏法／淋巴引流术能明显提升人体血清中超氧化物歧化酶（SOD）活办，并显著降低丙二醛（MDA）含量，表明香熏法／淋巴引流术具有抗氧化、清除体内自由基的作用。     

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.     

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.     

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.     

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.