农业

Asimple necessary and sufficient condition for global controllability will bepresented. The analysis method is based on some basic facts in planartopology such as the Jordan curve Theorem, and in the geometric theoryof ordinary differential equations including the Poincare-Bendixson Theo-rem.

分析方法主要是基于平面拓扑中的一些基本事实，比如Jordan曲线定理，以及常微分方程几何理论中的几个基本定理，如Poincare-Bendixson定理，指标定理等。

This study has provided first molecular evidence that the mRNA expression of CYP1A was significantly induced in response to domoic acid. We suggest that phaseⅠxenobiotic metabolizing enzymes CYP1A, instead of phaseⅡxenobiotic metabolizing enzymes GST, might be major detoxified enzymes in the metabolism of amnesic shellfish poisoning toxin, domoic acid.

我们认为第Ⅰ时相去毒酶CYP1A是DA代谢的关键的酶，它可通过生物转化降低DA的毒性，而第Ⅱ时相去毒酶GST在DA代谢过程中的作用不显著，使毒素不能被有效地排出体外。