富锌培养对姬松茸生长代谢的影响

研究了锌对食药用菌姬松茸生长代谢的影响,考察了姬松茸耐锌能力和富集能力以及锌对姬松茸多糖和氨基酸代谢的影响.结果表明:液体培养姬松茸对锌的最适富集质量浓度为300mg/L,在锌质量浓度为300 mg/L以内,锌对姬松茸菌丝量、多糖、氨基酸均有促进作用.锌的有机化分析表明82.2％的ZnSO4在姬松茸菌丝内以有机锌的形式存在,氨基酸分析结果显示,富锌后菌丝体和发酵液必需氨基酸含量与对照相比分别提高了12.3％和3.6％.     

姬松茸深层发酵培养基的优化

通过姬松茸碳氮源筛选的单因素实验 ,确定玉米粉、蔗糖为碳源 ,豆粕粉、麸皮汁为氮源 ;在此基础上 ,进行了碳氮源质量浓度及比例实验、摇瓶发酵正交实验 ,优化培养基配方 ,确定姬松茸摇瓶发酵培养基的最佳配方为 :玉米粉 1 .5g/dL ,蔗糖 0 .5 g/dL ,麸皮汁 0 .5 g/dL ,豆饼粉 2 .0 g/dL .     

姬松茸多糖提取条件及其沉淀特性

研究了不同的提取温度、提取时间和加水比 ,对姬松茸液体发酵菌丝体和固体栽培子实体粗多糖提取得率的影响 .采用二元二次回归的分析方法得姬松茸菌丝体和子实体的最佳提取条件为 :菌丝体为 10倍加水量于 90℃提取 3.3h ;子实体为 10倍加水量于 90℃提取 3.4h .提取率可以分别达到 1.376 %和 1.6 40 % .在此基础上 ,比较了乙醇质量分数和提取液 pH对姬松茸子实体和菌丝体多糖沉淀特性的影响 .     

肉桂醛微胶囊的制备工艺

研究了以阿拉伯树胶和麦芽糊精为壁材 ,喷雾干燥法制备微胶囊化肉桂醛的工艺条件 .探讨了壁材组成、乳化剂用量、固形物质量分数、芯壁比、进风温度、进料速度、喷射压力等对微胶囊化效果的影响 .经过正交试验 ,确定了最佳工艺条件 .实验结果表明 ,阿拉伯胶和麦芽糊精的最佳质量配比为 1∶1,蒸馏单甘酯的用量为 0 .4 g/dL ,固形物质量分数为 4 0 % ,芯材与壁材的配比为 1mL∶10 g ,肉桂醛微胶囊化的最佳喷雾干燥条件为进风温度 2 2 5℃ ,进料流量 2 10mL/h ,喷射压力0 .18MPa .实验还表明 ,肉桂醛微胶囊产品有一定的缓释抑菌效果 .     

在腹腔镜和传统剖腹结肠直肠手术失血及术后血制品的应用

设想腹腔镜结肠切除术中失血根据估计量血红蛋白值和所需输血量等测定 ,经传统剖腹结肠切除术为多 ,作者取Ohio洲Cleveland临床基金会结肠直肠外科 2 0 0 0～ 2 0 0 1年各 1 4 3例同一结肠直肠切除手术进行分析 ,按年龄、性别、诊断配对分别进行腹腔镜或剖腹手术 ,比较失血量。两组配对资料　腹腔镜和剖腹手术各 1 4 3例 ,其年龄 ( 5 3± 1 7∶5 4± 1 6岁 )、女性数 ( 74∶74)、体块指( 2 5 .7± 1 7∶2 6.7± 6.2kg/m2 )、手术前血红蛋白值( 1 3 .8∶1 3 .5 g/dL)、小肠切除例 ( 2∶2 )、回盲肠切除例( 1 4∶1 4 )、右半结肠切除 ( 3 3…     

松口蘑菌丝体糖蛋白MP的性质及其结构

通过聚丙烯酰胺凝胶电泳、红外、紫外扫描、气相色谱、氨基酸组成、β 消去反应等方法研究松口蘑菌丝体糖蛋白MP的结构性质,结果表明,该糖蛋白的相对分子质量为57000,红外扫描有典型的多糖吸收峰,糖苷键为α型;单糖组成为葡萄糖和木糖,摩尔比(r)为34∶1,紫外扫描有蛋白质吸收峰,蛋白质量分数为75.5%,多糖为24.5%,多糖与蛋白质为O 糖肽键连接.     

三维共培养体系促进去分化的软骨细胞再分化的实验研究

目的探讨海藻酸钠水凝胶三维共培养体系对去分化的软骨细胞再分化的影响。 方法将第1代(P1)软骨细胞及第4代(P4)软骨细胞分别与ATDC5按3 ∶1的比例在海藻酸钠水凝胶内进行三维共培养，即AP1组及AP4组。另建立单纯P1、P4及ATDC5的三维培养体系，即P1、P4及ATDC组，全部以软骨诱导液为培养基，提供外源性转化生长因子(TGF-β3)。培养28 d后，通过Q-PCR检测Ⅰ型胶原、Ⅱ型胶原、蛋白聚糖基因的表达情况，组织学染色观察等手段，比较各组的Ⅱ型胶原及蛋白聚糖基因的表达水平，结果以Bonferroni检验法进行统计学分析。 结果AP4组中Ⅱ型胶原及蛋白聚糖基因的表达明显上调，且与P1、P4组的差异有统计学意义(Ⅱ型胶原：F＝38.41，P<0.01；蛋白聚糖：F＝5，P<0.01)，且在组织学染色上也能观察到相关蛋白产物明显沉积。 结论三维共培养体系能让去分化的软骨细胞重新出现其特有的表型，其机制涉及细胞因子及细胞直接接触等方面。     

胃吸收草酸的研究

目的　探讨胃在外源性草酸吸收中的作用。方法　观察健康成人 (n =10 )和无胃者(胃全切除n =8)摄入 40 0 g菠菜泥前后尿草酸排泄 (mg/min)的动态变化 ,计算食入菠菜草酸的生物利用率并与无胃者进行比较。结果　摄入菠菜中草酸含量为 2 5 67～ 2 670mg ,健康成人摄入菠菜后 2 0min尿草酸排泄 (mg/min)较摄入菠菜前的基础水平明显增加 ;7/10参试者约在 40min出现第 1吸收峰 ,60min时尿草酸排泄 (mg/min)为 0 .0 73 2± 0 .0 2 94,较基础水平 0 .0 3 3 1± 0 .0 2 0 3高出 1倍 (P <0 .0 1) ,3h左右出现第 2吸收峰 ;无胃者草酸负荷后 60min的食物草酸生物利用率(0 .0 63± 0 .0 62 ) %较健康成人 (0 .0 98± 0 .0 71) %低 5 0 % (P <0 .0 1) ,且不出现第 1吸收峰。结论　胃在正常生理状况下是强有力的草酸吸收器官 ,胃的功能异常与草酸钙尿石形成的关系有待深入研究     

干扰素γ诱导蛋白10基因修饰小鼠树突状细胞的抗前列腺癌作用研究

目的　探讨转染干扰素γ诱导蛋白 10 (IP 10 )基因构建的加载树突状细胞 (DC)瘤苗 ,对特异性细胞毒T淋巴细胞 (CTL)的诱导作用。　方法　将RM 1细胞的裂解产物作为肿瘤抗原加载小鼠骨髓来源的DC(Tuly DC) ,将IP 10DNA插入真核表达质粒 ,通过脂质体法将IP 10基因转染至Tuly DC ,构建DC瘤苗 ;RT PCR法检测IP 10基因转染成功 ,趋化实验检测对淋巴细胞的趋化作用 ,混合淋巴细胞反应 (MLR)检测瘤苗刺激T细胞的增殖能力 ,MTT法检测瘤苗诱导的特异性CTL的杀伤活性。　结果　转染DC的IP 10表达明显增强 ,其上清对淋巴细胞有较强的趋化作用 ;DC瘤苗刺激T细胞增殖能力增强 ,每分钟闪烁计数值分别为 18913.0 9± 2 735 .33(1∶10 )和 17736 .6 7± 2 5 31.70 (1∶2 0 ) ,与各对照组相比差异有显著性意义 (P <0 .0 1) ;DC瘤苗诱导的CTL对RM 1细胞的特异性杀伤率分别为 (37.95± 5 .2 6 ) % (效靶比 2 0∶1)和 (43.87± 7.6 3) % (效靶比 4 0∶1) ,均高于各对照组 ,差异有显著性意义 (P <0 .0 1)。　结论　所构建的前列腺癌DC瘤苗能有效提高其抗原提呈功能和特异性CTL的诱导。     

柱前衍生反相高效液相色谱法分析碱性氨基酸

采用柱前衍生反相高效液相色谱法 (RP HPLC)测定碱性氨基酸含量 ,衍生化试剂为 2 ,4 二硝基氯苯 (CDNB) ,流动相为 0 .2mol/L的醋酸 醋酸盐缓冲液 ( pH 5 .2 0 )和甲醇的混合溶液 ,其体积配比为 75∶2 5 ,不需梯度洗脱 ;采用C18柱 ,在波长 36 0nm条件下进行紫外检测 ,碱性氨基酸质量浓度与峰面积呈良好的线性关系 ,相关系数均在 0 .98以上 ,分离效果较好 .     

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.     

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.     

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.     

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.