Nuclear phosphoprotein kinase activities in normal and neoplastic tissues.

Nuclear phosphoprotein kinases from normal rat liver and transplantable neoplasms were fractionated and compared. A phosphoprotein kinase fraction activated by Mn2+ was found to be present only in the neoplasms. This nuclear protein kinase phosphorylated nuclear proteins represented by one major and several minor bands as determined by polyacrylamide gel electrophoresis (M approximately 50,000).     

Solitary thyroid metastasis from clear-cell renal carcinoma.

A 58-year-old woman underwent nephrectomy because of clear-cell renal carcinoma. Seven years later a solitary thyroid metastasis was detected. She is alive and well 17 months after thyroidectomy. The rarity of this manifestation is well known but its explanation is not clear. The long metastasis-free interval, a characteristic shared by other hormonally dependent neoplasms, has been explained in part by the concept of "dormant cells", which do not undergo division. The stimulus that provokes these cells into division is at present not known.     

鄱阳湖湿地不同土地利用方式下土壤微生物群落功能多样性

于2011年5月分别采集鄱阳湖围垦92、48a和38a的水稻田,退田还湖25a的退耕地以及自然湿地共5个样地的表层土壤,利用Biolog-ECO板技术对土壤微生物群落的单一碳源利用情况进行了测定,并结合群落指数和主成分分析(PCA)对培养72 h土壤微生物群落功能多样性变化进行了分析。结果表明:退耕地和自然湿地土壤微生物群落利用31种碳源的能力较强,来自不同围垦年限的土壤微生物群落利用碳源能力均较弱;且随围垦时间的增长,土壤微生物对碳源的利用能力呈降低的趋势。自然湿地、退耕地与围垦92、38a样地土壤之间存在显著的微生物功能多样性差异;围垦对土壤微生物代谢糖类、羧酸类、氨基酸类物质的影响最为明显。结果提示,围垦改变了湿地土壤微生物群落结构,退田还湖有助于湿地土壤微生物群落结构的恢复。     

Population genetic diversity and structure of Rhinogobius candidianus (Gobiidae) in Taiwan: Translocation and release

Rhinogobius candidianus is a freshwater goby distributed in north, northwest, west, and south Taiwan, but this species has been introduced to east Taiwan and became dominant. To investigate its native population genetic diversity and structure and evaluate the sources and diversity of translocated populations, the mitochondrial DNA control region and cytochrome b gene (1981 bp) from 220 specimens were analyzed. These results indicated that (1) the east populations originated from two sources in west Taiwan; (2) translocated populations exist in east Taiwan and south Taiwan; (3) many populations have likely been moved secondarily by human intervention; (4) the effective size of the populations had declined greatly; (5) within the native populations, the ancestral populations colonized Taiwan during the land bridge phase in the Pleistocene through north Taiwan; (6) the landform changes in Taiwan shaped the population structure; and (7) the landforms of the coastline during glaciation also shaped the native range. The low‐level genetic diversity, high population differentiation, and population decline greatly suggest the need for resource management and conservation interventions. Four clades (α–δ) should be managed as four distinct evolutionarily significant units, while the translocated populations should be managed as separate management units. Moreover, the translocated populations in east Taiwan should be evaluated and monitored carefully.     

氮水添加对放牧背景下荒漠草原生产力的影响

水分与氮素作为干旱和半干旱草原生产力的共同限制性因子在退化草原的生态快速修复过程中备受关注。以不同放牧强度背景下的短花针茅荒漠草原为研究对象,开展围封模拟放牧利用实验,同时添加氮素和水分。通过分析历史放牧强度与年份对生产力的影响,以及添加氮素和水分对不同功能群植物生物量的作用,探讨放牧强度对短花针茅草原生产力的内在作用机制,以及如何实现荒漠草原资源合理开发和可持续利用。研究结果显示,降雨量与放牧强度决定着短花针茅草原的植物群落结构。氮素和水分添加可分别提升11%-29%和12%-32%的群落地上生物量,且二者存在显著的交互作用。不同功能群植物的地上生物量对氮素与水分添加的响应存在差异,多年生丛生禾草对氮素和水分添加响应最敏感。氮素与水分添加可显著提高多年生丛生禾草的地上生物量,但与自然降水量相关。氮素添加对地上生物量的影响在正常降雨和稍旱年份作用显著,而水分添加在干旱年份作用显著。在正常降雨年份,以半灌木植物为优势种的轻度放牧背景以添加水分对提升生产力最宜,以多年生丛生禾草和半灌木为共优种的中度放牧背景和以多年生丛生禾草为优势种的重度放牧以同时添加水分和氮素对提升生产力最为宜;在干旱年份不同放牧强度背景下均以同时添加水分和氮素对提升生产力最为宜。我们的结果表明了养分与资源的改善有利于退化短花针茅草原的快速恢复和可持续生产。     

中微量元素和有益元素对水稻生长和吸收镉的影响

采用盆栽试验,研究了中微量元素和有益元素对水稻生长和吸收镉的影响。结果表明,在所有测试的元素和施用方法中,硅酸钠叶面喷施显著增加稻谷产量,而碳酸钙、硼酸、硅酸钠土施和亚硒酸钠显著降低了稻谷产量。镁、锌、铁的盐酸盐形态对水稻籽粒的增产效果优于硫酸盐形态,而钙、铜的硫酸盐形态增产效果略高于盐酸盐形态。在钙、镁、硫三种中量元素中,钙增加了水稻籽粒中的Cd浓度和吸收量,而镁和硫则降低了籽粒中的Cd浓度和吸收量,以硫磺粉处理为最低。稻草中的Cd浓度和总量均以氯化镁处理为最高,硫磺粉处理最低。镁能有效抑制Cd从秸秆向籽粒的转移,其盐酸盐优于硫酸盐。在微量元素中,锌对水稻Cd的吸收抑制作用最为显著,其次是铜,而有益元素肥料硅酸钠叶面喷施则显著增加了稻谷中的Cd浓度和吸收量。硫酸亚铁、氯化锰、氯化铜、硼酸和硼砂处理都能有效地抑制Cd从秸秆向籽粒的转移,而硅酸钠叶面喷施和锌处理则促进了Cd的转移,表明硅酸钠抑制水稻吸收Cd的机制很可能发生在土壤中,而非在植株体内或地上部分。在Cd污染土壤上选用适宜的中微量和有益元素肥料及其施用方法,能有效降低水稻对镉的吸收和稻米中的Cd含量。     

锡林郭勒盟气候干燥度的时空变化规律

以锡林郭勒盟15个气象站点1981—2007年的月平均气温、月累积降水量数据为基础,在Arcgis软件的支持下,得到DeMartonne干燥度的空间数据。研究结果表明,锡林郭勒盟27a平均干燥程度自东向西递增;1981—2007年,锡林郭勒盟整体上表现出干燥度数值下降、干旱程度上升的趋势;从干燥度的年代,20世纪80年代和90年代是锡林郭勒盟气候相对湿润时期,21世纪初期,锡林郭勒盟大部分地区的气候呈现干燥度值减小、干燥程度加大的趋势,干性干旱区在空间分布上占据了主导地位,结果也打乱了原有的气候带状交替格局。21世纪初与20世纪80年代相比,各干燥度等值线的位置均发生了明显的东移现象。     

极端干旱区尾闾湖生态需水估算——以东居延海为例

以东居延海为研究对象,利用遥感技术目视解译ETM影像,提取东居延海2002—2012年各月湖面面积。通过水文保证率法确定不同保证率下的湖面面积,结合额济纳旗气象站观测的风速、相对湿度、气温、水汽压、降水量等气象数据估算湖泊蒸发耗水量和湖泊降水补给量,根据湖泊渗漏系数估算湖泊渗漏量,最后运用水平衡原理构建湖泊生态需水模型,估算了东居延海在湖面面积保证率为50%、75%、95%时各月月均和年均生态需水量,其中年均生态需水量分别为1.78×108、1.60×108、1.03×108m3,约占莺落峡年均径流量的9.66%、8.66%、5.59%,约占正义峡年均径流量的16.27%、14.60%、9.42%,约占狼心山年均径流量的30.81%、27.65%、17.84%。