白桦脂酸体外抗肿瘤的活性和机制

研究白桦脂醇（Betulin）和白桦脂酸（Betulinic Acid, BA）对3种癌细胞株的增殖抑制作用以及白桦脂酸诱导MCF 7细胞毒的分子机制. 应用结晶紫染色方法对白桦脂醇和白桦脂酸对肿瘤细胞的生长抑制作用进行筛选； 应用RT-PCR技术检测MCF 7细胞p21 mRNA, p53 mRNA, Bcl 2 mRNA和Bax mRNA的表达. 结果表明, 白桦脂醇和白桦脂酸有显著抑制肿瘤细胞生长的作用, 且有浓度依赖性; 白桦脂酸能够诱导MCF 7细胞凋亡, 并诱导其p21 mRNA和p53 mRNA表达增高, 但对其Bcl 2 mRNA和Bax mRNA 的表达无影响.     

硼酸基亲和层析纯化5-甲基尿苷

利用聚乙烯系大孔聚合物与间氨基苯硼酸偶联制备亲和介质，配基密度为每克湿胶0．92mmol。最佳吸附条件为pH9．0和2．0mol/LNaCl；最佳洗脱条件为0．1mol/LHCl。测定了吸附等温线，算得解离常数Kd为0．155mol/L，最大吸附量qm为每克湿胶78．8mg。将含有胸腺嘧啶的5－甲基尿苷溶液进行亲和层析，5－甲基尿苷收率为56．3％。     

对甲苯磺酸催化合成苯甲酸异戊酯

在对甲苯磺酸存在下,由苯甲酸和异戊醇合成苯甲酸戊酯.当苯甲酸、异戊醇和对甲苯磺酸的物质的量比为130.13,回流分水2h,酯收率达99%.     

莒县柠檬酸厂中和废水回用的研究

结合柠檬酸生产的特点，对中和废水中限制发酵的主要因素进行仔细研究。结果表明，中和废水经过pH值调节、活性炭吸附后，可以直接回用于发酵。这既减少了污染，又节约了水资源，具有良好的环境效益和经济效益。     

复合萃取剂醋酸乙二醛液液相平衡研究

研究了复合萃取剂醋酸乙二醛三元体系在 2 5℃时的液液相平衡关系 ,通过自动电位滴定仪测定了两平衡相中醋酸的含量 ,用浑浊法测定了体系的分层曲线 ,并绘出了三元相图。从三元相图看 ,复合萃取剂具有良好的萃取性能。     

Thymidine kinase gene mutation leads to reduced virulence of pseudorabies virus

To explore correlation between the tk gene structure of pseudorabies virus (PRV) and its virulence, to study the effect of the gene mutation on PRV biological properties, and to investigate mechinism of reduced virulence, thymidine kinase (TK)-deficient mutant of pseudorabies virus strain Hubei (PRV HB) was isolated by selection for resistance to 5-bromodeoxyuridine. The tk genes of PRV HB and its TK^― mutant were cloned and sequenced. 1587 base pairs of the tk gene and flanking regions of wild-type (wt) virus were sequenced, which included an open reading frame (ORF) of 1098 bp encoding a protein of 366 amino acids. The ORF contained two 137-bp repeated sequences, which were connected by an adenosine. 1458 bp of the tk and flanking regions of TK^― mutant were sequenced. Analysis of the tk gene sequence of TK^― mutant indicated that one of 137 bp repeated sequence and the connecting adenosine in the tk gene of the wt virus was deleted and a repeated sequence of 8 nucleotides (GCGCGCC) was inserted. All other nucleotides of TK^―mutant were identical to that of wt virus. Deletion and insertion of the nucleotide sequence resulted in a frameshift and a premature chain termination, and the resultant TK protein was not active. Analysis of the amino acid sequence revealed that TK protein of PRV HB contained the conserved consensus sequence of herpesviral TKs and an additional conserved-DHR-motif. The results of this work also indicated that TK^― mutant was genetically stable. Compared to PRV HB, virulence of TK^― mutant was greatly decreased. Mice vaccinated with TK^― mutant were completely protected against a lethal challenge with virulent PRV (HB).     

恶性肿瘤骨转移性骨痛的放射性核素治疗概况

综述了^32P,^89Sr,^153Sm等放射性核素治疗骨转移癌骨痛的机制，疗效和副作用，是一种有效的治疗方法。     

Cholinergic, monoaminergic and glutamatergic changes following perinatal asphyxia in the rat

Perinatal asphyxia (PA) is considered to lead to a variety of brain disorders including spasticity, epilepsy, mental retardation, and minimal brain disorder syndromes and may form the basis for psychiatric and neurodegenerative diseases later in life. We examined markers for neuronal transmission involved in the pathomechanisms of PA and candidates as mediators for long-term sequelae. We tested tyrosine hydroxylase (TH) and the vesicular monoamine transporter (VMAT) representing the monoaminergic system, the vesicular acetylcholine transporter (VAChT), and the excitatory amino acid carrier 1 (EAAC1), a neuronal subtype of the glutamate transporter, using immunohistochemistry on brain sections of rats subjected to graded PA. Three months following the asphyxiant insult immunoreactive (IR)-TH was decreased in striatum, hippocampus, thalamus, frontal cortex, and cerebellum; IR-VMAT was increased, and IR-VAChT was decreased in striatum. IR-EAAC1 glutamate transporter was increased in frontal cortex. The cholinergic, monoaminergic, and glutamatergic changes, still observed 3 months after the asphyxiant insult, may reflect their involvement in the pathomechanisms of PA and indicate mechanisms leading to long-term complications of PA. The variable consequences on the individual markers in several brain regions may be explained by specific susceptibility of cholinergic, monoaminergic, and glutamatergic neurons to the asphyxiant insult. Received 16 March 1999; received after revision 20 May 1999; accepted 8 July 1999     

Role of the δ 8 double bond of agroclavine in lysergic acid amide biosynthesis byClaviceps purpurea

Summary Agroclavine, given to actively-growing sclerotial tissue of a strain ofClaviceps purpurea which can not normally elaborate ergot alkaloids, was transformed by this tissue into lysergic acid amide with overall efficiency of approximataly 40%. By contrast, festuclavine (8, 9-dihydro-agroclavine) was not transformed, indicating specificity in the mechanism of lysergyl biosynthesis.     

反式蒈醛酸酯经差向异构化制取半缩醛内酯的研究

反式菊酸酯经臭氧化得蒈醛酸酯,然后在甲醇钠的甲醇溶液中发生差向异构,获得顺式蒈醛酸及它的半缩醛内酯的混合物,收率从原来文献报导的27％提高到60％。