正规类中遗传根的一个性质

在结合环中,Amitsur证明了：设R是遗传根,对环A的任意两个理想Ii,令Ii^-是由Ii^-/Ii=R（A/I）所唯一确定的A的理想,i=1,2,则有（I1∩I2^-)=I1^-∩I2^-。本文在更广泛的意义下证明此定理,推广了Amitsur的结果,同时给出它的几个应用。     

Nitric oxide biosynthesis, nitric oxide synthase inhibitors and arginase competition for L-arginine utilization

Nitric oxide (NO) is a recently discovered mediator produced by mammalian cells. It plays a key role in neurotransmission, control of blood pressure, and cellular defense mechanisms. Nitric oxide synthases (NOSs) catalyze the oxidation of L-arginine to NO and L-citrulline. NOSs are unique enzymes in that they possess on the same polypeptidic chain a reductase domain and an oxygenase domain closely related to cytochrome P450s. NO and superoxide formation as well as NOS stability are finely regulated by Ca²⁺/calmodulin interactions, by the cofactor tetrahydrobiopterin, and by substrate availability. Strong interactions between the L-arginine-metabolizing enzymes are clearly demonstrated by competition between NOSs and arginases for L-arginine utilization, and by potent inhibition of arginase activity by N^ω-hydroxy-L-arginine, an intermediate in the L-arginine to NO pathway.     

等离子体处理对聚醚氨酯表面浸润性和结构的影响

本文研究了经等离子体处理的医用聚醚氨酯材料。利用N_2和Ar气体在100W的放电功率和30ml·min~(-1)的束流下产生低温等离子体,处理时间从0到15分钟变化。表面浸润性是通过测量材料表面和蒸馏水的接触角变化完成的,结果表明随着处理时间的延长,接触角从78.8°下降到61°。XPS分析结果表明等离子体处理使材料表面的一些C-H键发生断键,这是浸润性提高的主因。ESR测量结果表明材料表面的自由基数量在处理后并未明显增加,这有利于临床应用。     

The effect of shock on blood oxidation-reduction potential

Oxidation-reduction (redox) potential measurements were made in the blood of rabbits subjected to hemorrhagic shock followed by treatment with a mild oxidizing agent (albumin). Control redox potential reading corrected for pH was –8.8±1.3 millivolts (mV) in arterial blood (A) and –18.0±2.0 mV in venous blood (V). This A-V difference indicated that hydrogen equivalents coming from muscle and other tissues were partially consumed in the lungs. A 20-mV drop on the V and a 13 mV on the A side was seen after shock. This did not fully return to control 2 h after return of the shed blood. Infusion of 2 g of albumin/kg/h raised the V redox potential to control, but it returned to untreated levels when the albumin was discontinued. The reductive load imposed on the animal by shock appeared to be large and not readily reversed by reperfusion or by the quantity of albumin given. Thus, it may be concluded that cellular respiration had not been adequately restored. This reductive load may impede recovery by suppression of cellular respiration and other cell and organ functions.     

加法范畴的Baer根和Levitzki根

在本文中我们定义加法范畴的Baer根和Levitzki根,并给出相应的结构定理,得到与通常环论中相应结果完全平行的命题.     

结合环下根的内部构造及下根构造的模刻划

对于给定的结合环类χ,本文给出了构造结合环A的χ下根的一个方法,并用模的语言刻划了下根的构造过程.     

NH2自由基电子基态及激发态解离通道的静力学分析

本文利用原子分子反应静力学的基本原理,研究了NH2自由基体系的可能解离通道,得到了NH2自由基电子基态2B1及第一激发态2A1合理的解离通道。     

玛咖多糖的提取条件及体外活性研究

优化玛咖多糖的提取条件,并通过体外实验对其抗氧化活性和降血脂功效进行研究。采用超声波辅助热水浸提并结合响应面法对玛咖多糖提取条件进行优化,通过自由基清除率评价玛咖多糖的抗氧化活性,基于玛咖多糖与胆酸钠的结合能力评价其降血脂功效。在提取温度50℃,提取时间42min,超声功率220W,料液比(g/mL)1∶32的条件下,多糖提取率达到最高11.0%。将玛咖粗多糖通过离子交换柱分离得到3个多糖组分,分别为玛咖多糖1、玛咖多糖2和玛咖多糖3。其中玛咖粗多糖、玛咖多糖1和玛咖多糖2具有较强的抗氧化活性,对DPPH自由基的较佳清除率分别为83.9%、81.8%和63.7%,对羟基自由基的较佳清除率分别为73.3%、56.8%和76.7%。此外,玛咖多糖3在体外对牛磺胆酸钠和甘氨胆酸钠的结合率分别为49.1%和32.3%。研究表明,玛咖粗多糖、玛咖多糖1和玛咖多糖2具有较好的抗氧化活性,玛咖多糖3具有一定的降血脂功效。     

正形阵与线性正形置换

利用矩阵的有理标准型理论，给出正形阵和线性正形置换的判定定理，构造性地解决了线性正形置换的结构问题。利用本原多项式理论解决了谷大武和肖国镇提出的最大线性正形置换的计数问题。     

正则环的d.f—根

引进了正则环的ｄ．ｆ－根概念,并利用ｄ．ｆ－根刻画了正则环的直有限性。