Fushun xian (Sichuan) zhi : 38 juan /

Double leaves, oriental style, in case.

杉科植物的表皮结构研究及古环境重建

全球古近纪和新近纪气候波动明显，很多科学家对古近纪和新近纪生物演化和气候演变规律的定量研究给予了相当的重视。杉科植物有长期发展的历史、少数的现存种和丰富的化石记录，成为指示古环境的理想植物之一。利用杉科植物重建古环境，首先要对化石植物进行正确的分类鉴定。杉科各属枝叶形态特征变异幅度较大，且枝叶排列和形态特征近似，有时各属之间存在交叉特征。杉科化石标本通常仅保存枝叶形式，且多个属的化石标本经常发现于同一地层，因而分类鉴定比较困难。植物的叶表皮结构是压型植物化石细胞信息的重要来源，是属种分类鉴定重要依据之一。本文在以往研究的基础上，完整分析了杉科9属现生植物的表皮特征，建立了杉科化石植物分类鉴定的现生植物的表皮特征参照系。 杉科植物的叶多为条形、钻形、鳞形或披针形，同种植物有1种、2种甚至3种叶型。其中水杉属的叶交互对生，其它属的叶螺旋状互生。水杉属的多数表皮细胞垂周壁明显弯曲，落羽杉属和杉木属有时微呈波状，其他属的表皮细胞垂周壁直。多数植物的叶片近轴面和远轴面的气孔数量和分布不同。一般来说，条形叶和披针形叶的远轴面气孔分布状况和气孔数量稳定，远轴面的中部最稳定。条形叶远轴面的气孔分布于中脉两侧，形成纵向的气孔带。条形叶近轴面气孔分布状况和气孔数量变化大，近轴面的气孔数量有时与远轴面近似，但多数情况下比远轴面少，有时整个叶片的近轴面仅少数几个气孔或没有气孔分布。钻形叶的近轴面和远轴面的气孔数量近似，或叶片近轴面的气孔数量比远轴面的气孔数量多，气孔分布范围也比远轴面气孔分布范围广。气孔椭圆形，落羽杉属植物和水松鳞形叶的气孔长轴方向与叶片长轴垂直或斜向排列，柳杉属植物的气孔多斜向排列，水松的条形叶和条状钻形叶的气孔多平行向排列。落羽杉属和柳杉属以外的杉科植物的气孔长轴多数与叶片长轴平行。在扫描电子显微镜下的密叶杉属植物叶片角质层的内表面，副卫细胞和表皮细胞的垂周壁与叶表面的角度一致，且副卫细胞的形态与表皮细胞类似，这种特殊气孔器被称为A-型气孔器。杉科植物中水杉属、落羽杉属和杉木属的气孔器近似密叶杉的这种A-型气孔器。台湾杉属、柳杉属、水松属、红杉属和巨杉属植物的气孔器与这种A-型气孔器不同，这几属的副卫细胞垂周壁表皮细胞的垂周壁方向不同，且副卫细胞的形态与表皮细胞的形态明显不同。因而气孔所有副卫细胞组成呈明显的圆盘状，保卫细胞在盘子的中央。综合分析植物的枝叶形态和表皮特征可以区分杉科各属。 本文研究了采自抚顺始新世的杉科植物标本，经枝叶特征、表皮结构和球果鳞片等特征分析为水松属的欧洲水松。论文分析了中国东北地区古温度定量研究结果与杉科植物的相关性。抚顺植物群发现有化石水杉M. occidentalis、中华红杉和欧洲水松，根据这三种化石植物的年均温度和年降水量，通过共存分析，推测抚顺始新世的年均温为12.1-17℃，年降水量为1199.6-2231mm。

Synergistic inhibition of tumor growth in a murine mammary adenocarcinoma model by combinational gene therapy using IL-12, pro-IL-18, and IL-1β converting enzyme cDNA

We report here that a cancer gene therapy protocol using a combination of IL-12, pro-IL-18, and IL-1β converting enzyme (ICE) cDNA expression vectors simultaneously delivered via gene gun can significantly augment antitumor effects, evidently by generating increased levels of bioactive IL-18 and consequently IFN-γ. First, we compared the levels of IFN-γ secreted by mouse splenocytes stimulated with tumor cells transfected with various test genes, including IL-12 alone; pro-IL-18 alone; pro-IL-18 and ICE; IL-12 and pro-IL-18; and IL-12, pro-IL-18, and ICE. Among these treatments, the combination of IL-12, pro-IL-18, and ICE cDNA resulted in the highest level of IFN-γ production from splenocytes in vitro, and similar results were obtained when these same treatments were delivered to the skin of a mouse by gene gun and IFN-γ levels were measured at the skin transfection site in vivo. Furthermore, the triple gene combinatorial gene therapy protocol was the most effective among all tested groups at suppressing the growth of TS/A (murine mammary adenocarcinoma) tumors previously implanted intradermally at the skin site receiving DNA transfer by gene gun on days 6, 8, 10, and 12 after tumor implantation. Fifty percent of mice treated with the combined three-gene protocol underwent complete tumor regression. In vivo depletion experiments showed that this antitumor effect was CD8+ T cell-mediated and partially IFN-γ-dependent. These results suggest that a combinatorial gene therapy protocol using a mixture of IL-12, pro-IL-18, and ICE cDNAs can confer potent antitumor activities against established TS/A tumors via cytotoxic CD8+ T cells and IFN-γ-dependent pathways.