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991.
闽东北雷竹尾梢长度与笋产量关系的初步研究   总被引:2,自引:1,他引:1  
采用随机区组试验设计法对雷竹保留尾梢长度与笋产量的关系进行研究,通过对比分析表明,钩梢比不钩梢的笋产量高,其中以保留竹尾长度1/3的笋产量最高,经济效益最好。  相似文献   
992.
矿区可持续发展系统动力学模拟与调控   总被引:16,自引:0,他引:16  
矿区是由资源、环境、经济和社会等子系统构成的复杂系统。矿区的可持续发展依赖于矿各子系统的合理结构和发展模式以及人们对系统的有效调控,将可持续发展思想 模拟方法相结合,在系统地分析矿区REES系统结构的基础上,构建了矿区REES系统动力学模型,并以铁法矿为例论述了矿区REES系统的模拟和调控等有关问题。  相似文献   
993.
Recovery of Bird Species in Minimally Restored Indonesian Tin Strip Mines   总被引:1,自引:0,他引:1  
Bird species richness and individual abundances were recorded in old, unrestored tin strip mine plots, in mined plots restored 1, 2, and 3 years before the study, and in adjacent, unmined, natural secondary forest plots on the 11,340‐km2 Indonesian island of Bangka (2°S, 106°E). The objective was to assess the ecological recovery of unrestored and minimally restored mine plots compared with surrounding reference forest. Unrestored mines had not been mined or used for any other purpose for 14–30 years; plots in their first, second, and third year since restoration were old mines planted with Acacia mangium (Leguminosae) at a density of 400 trees/ha. Natural secondary forest plots 20 or more years since the last disturbance were immediately adjacent to both unrestored and restored plots. Bird surveys on 4‐ha plots were performed during the 1995 breeding season. A comparison of data from unrestored plots of widely varying ages showed no significant differences among them for species richness, diversity (Shannon–Wiener index, H′), or individual abundance, indicating that little natural bird community recovery had occurred over time in the plots. However, increases did occur in restored sites over only 3 years for both species richness (r 2 = 0.29, p = 0.04) and diversity (r 2 = 0.45, p = 0.009). All values for third‐year restored plots, however, were still significantly lower than corresponding values for adjacent natural secondary forest plots. The quick return of bird activity on the plots after minimal efforts at restoration supports the idea that simple, inexpensive restoration can be effective for “jump starting” degraded systems at large scales. Such a restoration strategy might be of particular value for degraded land in developing nations, where scientific, professional, and financial resources might be in short supply. Using this strategy, a small number of restoration professionals could mobilize the labor of many local people in many areas, serving to both improve ecological systems and to educate and engage local populations in restoration and conservation projects.  相似文献   
994.
995.
The rapid increase in collateral omics and phenotypic data has enabled data-driven studies for the fast discovery of cancer targets and biomarkers. Thus, it is necessary to develop convenient tools for general oncologists and cancer scientists to carry out customized data mining without computational expertise. For this purpose, we developed innovative software that enables user-driven analyses assisted by knowledge-based smart systems. Publicly available data on mutations, gene expression, patient survival, immune score, drug screening and RNAi screening were integrated from the TCGA, GDSC, CCLE, NCI, and DepMap databases. The optimal selection of samples and other filtering options were guided by the smart function of the software for data mining and visualization on Kaplan-Meier plots, box plots and scatter plots of publication quality. We implemented unique algorithms for both data mining and visualization, thus simplifying and accelerating user-driven discovery activities on large multiomics datasets. The present Q-omics software program (v0.95) is available at http://qomics.sookmyung.ac.kr.  相似文献   
996.
SNP抑制5-HT诱导的胞内游离钙浓度升高和内钙释放   总被引:2,自引:0,他引:2  
用Fura - 2/AM 荧光测量技术研究了5 - 羟色胺(5- HT) 诱导的大鼠尾动脉平滑肌细胞胞内钙升高和一氧化氮(NO) 的抑制效应。实验表明, 胞外0m mol/ L Ca2 + 时胞内静息[Ca2 + ] i 为20 .2±8 .6nmol/L(n = 8) 。10μmol/L 5- HT 可诱导出胞内钙库释放引起的瞬态[Ca2 +]i 升高,其峰值达245 .7 ±71.6nmol/ L(n = 6) 。10 - 7 mol/L 硝普钠(SNP) 可抑制5- HT 诱导的[Ca2 +]i 升高,其峰值浓度降为75.1±35 .9nmol/L(n = 5) 。当细胞浴液含2.5m mol/L Ca2 + 时,静息[Ca2 +]i为112 .8 ±10 .3nmol/ L(n = 5) , 这时10μmol/ L 5 - HT 可诱导[Ca2 + ] i 的峰值为252 .3 ±80 .6nmol/L(n = 4) ,以及其后平台浓度为143 .0 ±37 .6nmol/L(n = 4) ,略大于[Ca2 +]i 为112.8 ±10 .3nmol/L 的静息浓度,为外钙内流引起。10 - 7 mol/L SNP 也可抑制5- HT 诱导[Ca2 + ]i 平台相浓度。平台浓度由143 ±47  相似文献   
997.
3'-End processing of pre-mRNA in eukaryotes   总被引:1,自引:0,他引:1  
  相似文献   
998.
999.
Numerous studies on cancers, biopharmaceuticals, and clinical trials have necessitated comprehensive and precise analysis of protein O-glycosylation. However, the lack of updated and convenient databases deters the storage of and reference to emerging O-glycoprotein data. To resolve this issue, an O-glycoprotein repository named OGP was established in this work. It was constructed with a collection of O-glycoprotein data from different sources. OGP contains 9354 O-glycosylation sites and 11,633 site-specific O-glycans mapping to 2133 O-glycoproteins, and it is the largest O-glycoprotein repository thus far. Based on the recorded O-glycosylation sites, an O-glycosylation site prediction tool was developed. Moreover, an OGP-based website is already available (https://www.oglyp.org/). The website comprises four specially designed and user-friendly modules: statistical analysis, database search, site prediction, and data submission. The first version of OGP repository and the website allow users to obtain various O-glycoprotein-related information, such as protein accession Nos., O-glycosylation sites, O-glycopeptide sequences, site-specific O-glycan structures, experimental methods, and potential O-glycosylation sites. O-glycosylation data mining can be performed efficiently on this website, which will greatly facilitate related studies. In addition, the database is accessible from OGP website (https://www.oglyp.org/download.php).  相似文献   
1000.

Introduction:

Armed conflicts affect territories rich in resources and biodiversity. As a result of the environmental damage caused by violent actions, the health of populations can be affected.

Objectives:

To assess the risks to human health due to environmental degradation associated with three violent actions in the context of the Colombian armed conflict: Pipeline bombing, informal mining with mercury, and spraying of illicit crops with glyphosate.

Materials and methods:

We conducted a quantitative evaluation of the risks to individual health associated with armed conflict activities using methodologies focused on the routes of pollutants dispersion, their concentrations in the environment, the exposure of the individuals, and the risks of carcinogenic and non-carcinogenic effects.

Results:

The risk assessment of the armed conflict-related actions under study evidenced intolerable carcinogenic risk and unacceptable non-carcinogenic risk due to the consumption of water and fish contaminated by polycyclic aromatic hydrocarbons (PAH), mercury, and glyphosate.

Conclusions:

The study reiterates the inextricable connections existing among the environment, society, and health, as well as the implications of environmental violence for the public health of vulnerable population groups and, in general, for the well-being of all living beings affected by the armed conflict.  相似文献   
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