鸣禽鸟的发声中枢及其神经传导通路的研究

鸣禽鸟的发声中枢及其神经传导通路的研究曾庆华，赵玲，姜立嘉（东北师范大学生物系）鸣禽鸟之所以能发出婉动听的鸣叫，不仅仅是依赖于外围发声器（鸣管）来完成，而是经过多级水平的相关中枢组成的机能系统密切配合统一调节方能完成的。这个机能系统称它为各级发声中枢...     

蜂胶高生物活性黄酮组分的研究

本文探讨了蜂胶总黄酮中最具活性的黄酮类物质的提取分离、官能结构特征与功能关系、可能的功效,进而提出了如何看待蜂胶总黄酮含量高低的问题.     

泰山月观峰和索道站冲沟生态治理探讨

为保护自然生态，对泰山月观峰和索道站冲沟采取了生态治理措施，取得了良好的效果，恢复了泰山自然景现，达到了保护生态环境的目的。     

金乡地膜大蒜种植技术

金乡县是中国著名的大蒜之乡,所产大蒜个大皮白,具有较高的食用价值和药用价值.现将金乡地膜大蒜种植技术介绍如下:     

再论生长的冗余

生长冗余概念是由盛承发在１９９０年首先提出来的。本文从作物个体与群体对立统一关角度出发提出了作物生长冗余的一个解释。盛承发提出的随机波动环境假说可以导致生长冗余的产生；但是，他从物种利益角度出发解释生物进化还有待商榷。本文还综述了黄土高原阗干旱雨养农业地区小麦根系生长冗余问题，并根据前入工作提出适度增加播种深度和苗期叶片刈割等高产栽培措施。     

Sequence of the canine c-yes proto-oncogene

Cloning of the canine yes oncogene was attempted from a c library derived from a healthy canine spleen using a human c-yes-1 probe. The nucleotide and amino acid sequences revealed that the canine yes gene contained an open reading frame consisting of 539 amino acids. Its product had a molecular mass of 60,368 Daltons and showed 95·9 per cent and 90·4 per cent homology with human and chick p61^c-yes, respectively. Moreover, the product had a myristylation signal, src homology region (SH) 3, SH2, and tyrosine kinase domains showing 98·8 per cent and 96·0 per cent homology with those of human beings and chickens, respectively. These findings indicate that the products of the canine yes gene may have non-receptor-type tyrosine kinase activity on the cell membrane, as is the case in human and chick p61^c-yes     

西杂牛连续埋植“畜大壮”效果观察

本试验对甘肃河西地区西杂１－２岁和周岁以下的犊牛连续用促生长剂“畜大壮”分阶段进行耳根埋植,试验结果表明,４－６月龄犊牛全期１８０天,试验组增重和平均日增重分别为５．５ｋｇ和３０８．３３ｇ,试验组比对照组提高３７．２５ｋｇ和２０６．９４ｇ（Ｐ〈０．０１）,１－２岁牛全期１８０天,试验组平均增重和日增重分别为５６．４３ｋｇ和３１４．４９ｇ,试验缄比对照组分别提高３０．０３ｋｇ和１６６．８２ｇ差异显著     

香菇干制微机监控系统研究

本文研究香菇干制过程的计算机控制。在研制了系统硬件之后,根据实验结果,确定了控制对象的广义数学模型,用飞升曲线法求取模型中各参数。用计算机仿真技术对几种常用的算法进行比较,得出了采用大林算法的控制方案。     

应用灰色关联度分析法综合评价高羊茅品种初探

应用灰色关联度分析法,对2000～2002年本院引进的13个高羊茅品种的适应性鉴定结果进行评估,其评估结果与品种的实际表现基本一致,说明应用关联度分析法综合评价草坪品种是可行的。分析结果:皇后、贝克、上南都的关联系数与理想品种最接近,是种植高羊茅草坪的首选品种。     

Age-related resistance to Pseudomonas syringae pv. tomato is associated with the transition to flowering in Arabidopsis and is effective against Peronospora parasitica

As plants mature it has been observed that some become more resistant to normally virulent pathogens. The ability to manifest the Age-Related Resistance (ARR) response in Arabidopsis to Pseudomonas syringae pathovars tomato (Pst) coincided with the transition to flowering in plants both delayed and accelerated in the transition to flowering. ARR was also associated with a change in PR-1 gene expression, such that young plants expressed PR-1 abundantly at 3 days post inoculation (dpi) while mature plants expressed much less. The Arabidopsis ARR response requires SA accumulation via isochorismate synthase (ICS1) [24]. ICS1 was expressed one dpi with virulent and avirulent Pst in both young and mature plants. The ARR response was also effective versus avirulent Pst providing an additional 4-fold limitation in bacterial growth. Arabidopsis ARR was found to be ineffective against two necrotrophs, Erwinia carotovora subspecies carotovora (bacterium) and Botrytis cinerea (fungus) and one obligate biotroph, Erysiphe cichoracearum (fungus). However, mature wild type, SA-deficient sid2 and NahG plants supported little growth of the obligate biotrophic oomycete, Peronospora parasitica. Therefore ARR to P. parasitica appears to be SA-independent, however the level of ARR resistance was somewhat reduced in these mutants in some experiments. Thus, there may be numerous defence pathways that contribute to adult plant resistance in Arabidopsis.