植物细胞大小与植物倍性关系的实验探索

本实验以同种植物的不同倍性个体叶片为材料,利用市售指甲油制取植物叶片表皮细胞的复制膜,制成临时装片,通过测量比较气孔保卫细胞的密度和面积,探索植物细胞大小与植物倍性的关系。本实验方法可进一步拓展应用于多倍体植物的鉴定。     

植物学专业课教学的尝试

职业高中教学改革应突出职业高中教学特点,注重学生实际操作能力的培养,提高学生的劳动技术水平,这样才能培养出适应现代化建设需要的中初级技术人才。     

Synthetic and biological studies on a cyclopolypeptide of plant origin

Objective: A natural cyclic peptide previously isolated from Citrus medica was synthesized by coupling oftetrapep-tide units Boc-Leu-Pro-Trp-Leu-Ome and Boc-Ile-Ala-Ala-Gly-Ome after proper deprotection at carboxyl and amino terminals followed by cyclization of linear octapeptide segment.Methods: Solution phase technique was adopted for the synthesis of cyclooctapeptide--sarcodactylamide.Required tetrapeptide units were prepared by coupling of Boc-protected dipeptides viz.Boc-Leu-Pro-OH and Boc-Ile-Ala-OH with respective dipeptide methyl esters Trp-Leu-Ome and Ala-Gly-Ome.Cyclization of linear octapeptide unit was done by p-nitrophenyl ester method.The structure of synthesized cyclopolypeptide was elucidated by FTIR,1H NMR,13C NMR,FABMS spectral data and elemental analysis.The newly synthesized peptide was evaluated for dif-ferent pharmacological activities including antimicrobial,anthelmintic and cytotoxic activities.Results: Synthesis of sarcodac-tylamide was accomplished with >78% yield utilizing dicyclohexylcarbodiimide (DCC) as coupling agent.Newly synthesized peptide possessed potent cytotoxic activity against Dalton's lymphoma ascites (DLA) and Ehrlich's ascites carcinoma (EAC) cell lines,in addition to moderate anthelmintic activity against earthworms Megascoplex konkanensis,Pontoscotex corethruses and Eudrilus sp.Moreover,cyclopolypeptide displayed good antimicrobial activity against pathogenic fungi Candida albicans and Gram-negative bacteria Pseudomonas aeruginosa,in comparison to standard drugs griseofulvin and ciprofloxacin.Conclusion: Solution phase technique employing DCC and triethylamine (TEA) as base proved to be effective for the synthesis of natural cyclooctapeptide.N-methyl morpholine (NMM) was found to be a better base for the cyclization of linear octapeptide unit in comparison to TEA and pyridine.     

淮河源国家森林公园植物资源研究

淮河源国家森林公园位于河南省西南部、桐柏山腹地，共有维管植物181科，785属，1886种及变种，具有丰富的中草药植物资源、观赏植物资源和许多珍稀濒危植物。森林植被垂直分布差异明显，植物种类多方交汇，南北兼容，有许多原始或古老的科属，是一个温带性质的植物区系，而且温带成分和亚热带到暖温带过渡类型突出，其植物的进化类型、生活型具有丰富的多样性。     

植物组织培养中的玻璃化现象

本文叙述了植物组织培养过程中，出现的玻璃苗解剖学特点、生理生化变化、形成原因及预防措施。     

人工诱变在植物病原真菌研究中的应用

分别介绍了物理诱变、化学诱变和插入突变在病原真菌遗传变异规律和致病机理研究中的应用.     

谈“吃”

本试图通过对以“喫”代“食”和以“吃”代“喫”的分析来理解“吃”表示“把食物放入口中经咀嚼咽下”之义的出现原因和发展历程。     

曹魏的封爵制度与食封支出

建安时期是曹魏代汉的政治过渡期,其封爵制度在爵级、爵称、封赏对象等方面大体沿用东汉之制。不过 囿于户口严重减耗,从田租户调获得的财政收入相当有限,为优先保证军费开支,曹魏的列侯食封制度作为一项财政 支出制度,比东汉有较大变化,主要表现为乡亭侯食封户数大为减少。同时,建安时期曹魏极少用进封爵级酬赏军 功,并创设四种“皆不食租”的爵级,也都是出于减少财政支出的考虑。曹魏代汉之后,财政状况大为好转,列侯封 爵制度基本沿用建安之制。不过,由于授封标准放宽,增加了县侯、王侯二类享受大量食邑户的封爵对象,加上曹魏 后期逐步控制政权的司马氏集团,加紧改朝换代的准备,有意将封爵食封作为笼络人心的政治手段和财政手段加以运 用,以致食封支出继续增长。曹魏代汉之后食封支出得以持续增长,是以在籍户口及其租调收入逐渐增多为财政基础 的。