Suicide substrate reaction-diffusion equations: Varying the source

The suicide substrate reaction is a model for certain enzyme-inhibitingdrugs. This reaction system is examined assuming that the substratediffuses freely while the enzyme remains fixed. Two sets ofinitial and boundary conditions are examined: one modellingan instantaneous point source, akin to an injection of substrate,the other, a continuous point source, akin to a continuing influx,or intravenous drip, of substrate. The quasi-steady-state assumptionis applied to obtain analytical solutions for a limited parameterspace. Finally, further applications of numerical and analyticalexperimentation on pharmaceutical mechanisms are described.     

比色法测定维生素B1片含量的研究

本文实验比较了某些现有光度测定ＶＢ１方法，提出用盐酸苯肼－亚硝酸钠试剂与维生素Ｂ１反应生成橙红色溶液，进行光度测定，对比度△λ为９１ｎｍ，灵敏度，ε（４９７ｎｍ）＝１．１×１０４Ｌ·ｍｏｌ（－１）·ｃｍ（－１），在０～１０μｇ／ｍｌ范围内线性关系良好。用本法测定维生素Ｂ１片的含量，标准加入回收率范围为１００％～１０３％，片剂测定与中国药典１９９０年版紫外分光光度法测定结果一致。     

不同光凝接触镜填充液对中央角膜厚度的影响

目的　比较在行氩激光全视网膜光凝治疗中使用不同接触镜填充液对中央角膜厚度的影响 ,以寻找最适用于该治疗的填充液。方法　对 4 6例 (5 2眼 )患者进行氩激光全视网膜光凝治疗 ,每次分别随机使用 0 2 5 %氯霉素、1%羧甲基纤维素及医用透明质酸钠组作为安放全眼底激光角膜接触镜填充液 ,在治疗前及治疗后均用角膜测厚仪测量患者中央角膜厚度。结果　治疗后使用 0 2 5 %氯霉素组中央角膜平均增厚 (31 4± 10 2 ) μm ,1%羧甲基纤维素组中央角膜平均增厚 (10 6± 4 3) μm ,医用透明质酸钠组中央角膜平均增厚 (8 0± 3 5 ) μm。方差分析显示 :氯霉素组与另两组差异有极显著性意义 (P <0 0 1) ,羧甲基纤维素组与透明质酸钠组差异无显著性意义 (P >0 0 5 )。结论　 1%羧甲基纤维素及医用透明质酸钠作为安放全眼底激光角膜接触镜的填充液对角膜水肿程度的影响明显小于0 2 5 %氯霉素 ,是可供选用的优良填充液     

高渗氯化钠羟乙基淀粉40注射液高容量血液稀释对大鼠肝脏缺血再灌注损伤的影响

Objective To investigate the effects of hypervolemic hemodilution (HH) with hypertonic saline plus hetastarch solution 40 injectio on hepatic ischemia-reperfusion (I/R) injury in rats. Methods Thirty male Wistar rats weighing 300-350 g were randomly divided into 3 groups ( n = 10 each): group I sham operation (group S); group II I/R and group Ⅲ HH. Partial liver ischemia was produced by clamping hepatic portal vein and left arteria hepatica for 30 min with atraumatic mini-clamp, followed by 2 h of reperfusion in I/R group and HH group. In HH group the animals were infused hypertonic saline plus hetastarch solution 40 injectio 10 ml/kg through vena caudalis over 30 min and then hepatic I/R was performed IS min after the infusion.The animals were killed at 2 h of reperfusion. The left liver was removed and blood sample was taken from inferior caval vein for determination of (1) serum alanine amino transferase (ALT) and aspartate amino transferase (AST) activities; (2) superoxide dismutase ( SOD) activity and malondialdehyde ( MDA) content in the liver; ( 3 ) microscopic examination. Results The serum ALT and AST activities and MDA content in the liver were significantly higher, SOD activity in the liver significantly lower after hepatic I/R and pathological changes in the liver severer in group I/R and HH than in group S. The serum ALT and AST activities and MDA content in the liver were significantly lower, SOD activity in the liver significantly higher after hepatic I/R and pathological changes in the liver milder in group HH than in group I/R. Conclusion Hypervolemic hemodilution with hypertonic saline plus hetastarch solution 40 injectio can ameliorate hepatic I/R injury by decreasing oxygen free radical production in rats.     

Influence of different preservation solutions and intentional hemodilution of recipient on viability of preserved and transplanted rat kidneys

Abstract. A total of 81 rat kidney grafts, flushed out and cold stored in either Sacks' or University of Wisconsin (UW) solution, were transplanted into hemodiluted (Hct = 30%± 4%) or untreated (Hct = 43%± 3%) recipients. The cold ischemia times (CIT) used were 24 and 36 h. One week after transplantation, the surviving recipients ( n = 67) were contralaterally nephrectomized. The experiment was terminated after a total period of 4 weeks, and the percentage of surviving animals was determined for each treatment. Data was pooled and the results show that grafts cold stored in UW solution were viable to a significantly greater extent and after longer CIT than grafts cold stored in Sacks' solution (47% vs 23%; P < 0. 05). Recipient hemodilution did not improve graft viability (39% vs 32%; NS). Kidneys cold stored for 24 h were viable to a greater extent than kidneys with a CIT of 36 h (50% vs 15%; P < 0. 01).     

臭氧水对SARS病毒的灭活效果观察

为了观察电解法产生的臭氧水对SARS病毒的灭活效果,采用悬液灭活试验法进行了试验。结果,以臭氧含量为27.73mg/L,作用4min可完全灭活SARS病毒;以臭氧含量为17.82mg/L,作用4min和4.86mg/L作用10min,均可使SARS病毒的灭活率达100％。结论,电解法产生的臭氧水含臭氧量达到4.86mg/L以上,对悬液内SARS病毒具有很强的灭活效果。     

Direct solution to an optimal control problem of econometric systems

A direct solution is proposed to an optimal control problem of linear econometric systems with a quadratic welfare loss function when there are linear equality constraints on the control variables. The direct solution proposed here eliminates the problem of non-uniqueness of the optimal solution, which is present when this optimal control problem is solved using the recursive algorithm proposed by Chow,¹ Pindyck² and Tan.³ If a unique solution to the optimal control problem exists, then the direct solution and the recursive solution coincide.     

急性阑尾炎术中外用过氧化氢液冲洗疗效观察─—附50例报告

本文报导采用过氧化氢液在急性阑尾炎术对局部腹腔及切口进行冲洗的方法。并用５０个病例进行了对比分析。认为此法简单、可靠。对腹腔脓肿，预防切口感染有一定效果。可适用于一般基层医院。     

太极通天液治疗血管性痴呆的疗效评价

目的：评价太极通天液治疗血管性痴呆的临床疗效。方法：随机将148例血管性痴呆分为太极通天液治疗组和丹参口服液对照组，另接应用韦氏成人智力量表评分，将血管性痴呆组分为3个亚组：即80－89分组，70－79分组和70分以下组，观察期为3个月。结果：太极通天液治疗前后WAIS－RC评分与对照组比较，80－89分组和70－79分组均有统计学差异（P＜0．05），而70分以下组无统计学差异（P＞0．05），结论：太极通天液对血管性痴呆有较好的治疗效果，且与痴呆病情程度有关。     

信息超载现象的传播效果分析及其解决对策

文章从传播效果的角度详尽分析了多媒体教学和网络教学中的信息超载现象,并提出相应的解决对策。