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991.
葡萄糖调节蛋白78(GRP78)是细胞内一种应急蛋白,它通过对细胞内、外胁迫因子产生强烈的应答而调节内质网稳态.草鱼(Ctenopharyngodon idellus)GRP78克隆于草鱼肝肾cDNA文库,全长2 490 bp.其中,5'非编码区为155 bp,含有7个热休克元件,3'非编码区为373 bp,最大开放阅读框为1 962 bp,编码653个氨基酸.序列分析表明,草鱼GRP78的N端包含3个HSP70家族的签名序列,C末端为内质网蛋白滞留信号KDEL,草鱼GRP78与人及其它动物的同源性很高.适应性进化分析也显示GRP78非常保守,受到强烈的功能约束,说明该蛋白质在进化中非常重要.RT-PCR分析表明,相对于本底水平,34℃热激和Poly I:c诱导后,草鱼GRP78在肝、肾等组织巾的表达明显上调.图4表1参16 相似文献
992.
993.
介绍了LSH-02G克劳斯尾气加氢催化剂的生产工艺及工业应用情况。LSH-02G催化剂具有一定的大孔,可减少CO在催化剂孔道中的停留时间,显著提高催化剂的COS水解率。LSH-02G催化剂工业应用结果表明:装置在80%、100%和110%负荷下运行,各项参数运行正常,急冷水pH稳定在7.8~8.0,急冷塔顶在线氢气含量(φ)维持在1.8%~2.2%,加氢反应器无SO2穿透。加氢反应器中SO2加氢转化率均为100%,COS水解率均在92%以上,符合普光天然气净化厂加氢催化剂技术规格书要求(SO2加氢转化率100%,COS水解率达90%以上)。 相似文献
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995.
Russian Journal of Ecology - 相似文献
996.
997.
The ratio between (Ca +K +Mg) and Al in nutrientsolution has been suggested as a predictive tool forestimating tree growth disturbance. However, the ratiois unspecific in the sense that it is based on severalelements which are all essential for plant growth;each of these may be growth-limiting. Furthermore,aluminium retards growth at higher concentrations. Itis therefore difficult to give causal and objectivebiological explanations for possible growthdisturbances. The importance of the proportion ofbase-cations to N, at a fixed base-cation/Al ratio, isevaluated with regard to growth of Picea abies.The uptake of elements was found to be selective;nutrients were taken up while most Al remained insolution. Biomass partitioning to the roots increasedafter aluminium addition with low proportions of basecations to nitrogen. We conclude that the low growthrates depend on nutrient limitation in thesetreatments. Low growth rates in the high proportionexperiments may be explained by high internal Alconcentrations. The results strongly suggest thatgrowth rate is not correlated with the ratio in therooting medium and question the validity of usingratios as predictive tools for estimating forestdamage. We suggest that growth limitation of Picea abies in the field may depend on lowproportions of base cations to nitrate. It istherefore important to know the nutritional status ofthe plant material in relation to the growth potentialand environmental limitation to be able to predict andestimate forest damage. 相似文献
998.
ANU A. GOKHALE 《Environmental management》2001,28(2):187-193
India is fast finding its place in the industrialized world and that is beginning to raise its environmental consciousness.
The Delphi technique was used to prioritize specific needs and articulate a sustainable urban improvement strategy for the
city of Mumbai (formerly Bombay). The Delphi technique is a means of achieving consensual validity among raters by providing
them feedback regarding other raters' responses. Mumbai has several indigenous environmental groups that were tapped for activists
and leaders; the study was conducted using ten environmentalists. In the initial phases the responses resulted in a range
of possible program alternatives. The last two stages helped to seek out information that generated a consensus on the part
of the respondent group. Statistical analysis methods included a hierarchical cluster analysis, mean, median, mode, and percent
of agreement calculations using SPSS software. The face-to-face discussion in phase 4 clarified some issues and helped the
group as a whole to outline the strategy for putting in place the essential elements of a framework to improve the quality
of life in an urban environment. 相似文献
999.
KATHLEEN E. HALVORSEN 《Environmental management》2001,28(2):179-186
Public participatory techniques have been the focus of a large and growing body of environmental literature. There is some
consensus among those who study these techniques that there is a need to develop and implement new techniques that meet certain
criteria. These include that the techniques be comfortable, convenient, and satisfying to participants. Authors have also
frequently called for the use of deliberative techniques, which allow participants to express and listen to a variety of perspectives
regarding the issue at hand. However, the literature on public participation lacks a set of widely applicable evaluation methods
to determine whether participants in techniques find them comfortable, convenient, satisfying, or deliberative. This paper
reports on the implementation of two different techniques that participants scored fairly high on all of these factors, as
well as the scale-based survey questions developed to measure these factors. 相似文献
1000.
We analyzed the relation of the amount and spatial pattern of land cover with stream fish communities, in-stream habitat,
and baseflow in 47 small southeastern Wisconsin, USA, watersheds encompassing a gradient of predominantly agricultural to
predominantly urban land uses. The amount of connected impervious surface in the watershed was the best measure of urbanization
for predicting fish density, species richness, diversity, and index of biotic integrity (IBI) score; bank erosion; and base
flow. However, connected imperviousness was not significantly correlated with overall habitat quality for fish. Nonlinear
models were developed using quantile regression to predict the maximum possible number of fish species, IBI score, and base
flow for a given level of imperviousness. At watershed connected imperviousness levels less than about 8%, all three variables
could have high values, whereas at connected imperviousness levels greater than 12% their values were inevitably low. Connected
imperviousness levels between 8 and 12% represented a threshold region where minor changes in urbanization could result in
major changes in stream condition. In a spatial analysis, connected imperviousness within a 50-m buffer along the stream or
within a 1.6-km radius upstream of the sampling site had more influence on stream fish and base flow than did comparable amounts
of imperviousness further away. Our results suggest that urban development that minimizes amount of connected impervious surface
and establishes undeveloped buffer areas along streams should have less impact than conventional types of development. 相似文献