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目的
分析县级医院医务人员的稳定性以及影响因素,以促进县级医院人才队伍的稳定性建设。方法 通过对我国4个省12家县级医院的在职医务人员进行现场调查,运用描述性与卡方检验的方法进行统计学分析。结果 有51.9%的县级医院医务人员都表示曾经想过离开本单位,而且高层次人才具有较高的离职倾向。工作条件中的业务活动经费不足和加班太多,以及工作困扰中的没有合作团队、工作不受重视和人际关系不和谐会显著影响县级医院医务人员的稳定性。结论 通过各种途径稳定人才队伍是县级医院得到长效发展的关键。 相似文献
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Yakov A. Tsepilov So-Youn Shin Nicole Soranzo Tim D. Spector Cornelia Prehn Jerzy Adamski Gabi Kastenmüller Rui Wang-Sattler Konstantin Strauch Christian Gieger Yurii S. Aulchenko Janina S. Ried 《Genetics》2015,200(3):707-718
Genome-wide association studies (GWAS) are widely applied to analyze the genetic effects on phenotypes. With the availability of high-throughput technologies for metabolite measurements, GWAS successfully identified loci that affect metabolite concentrations and underlying pathways. In most GWAS, the effect of each SNP on the phenotype is assumed to be additive. Other genetic models such as recessive, dominant, or overdominant were considered only by very few studies. In contrast to this, there are theories that emphasize the relevance of nonadditive effects as a consequence of physiologic mechanisms. This might be especially important for metabolites because these intermediate phenotypes are closer to the underlying pathways than other traits or diseases. In this study we analyzed systematically nonadditive effects on a large panel of serum metabolites and all possible ratios (22,801 total) in a population-based study [Cooperative Health Research in the Region of Augsburg (KORA) F4, N = 1,785]. We applied four different 1-degree-of-freedom (1-df) tests corresponding to an additive, dominant, recessive, and overdominant trait model as well as a genotypic model with two degree-of-freedom (2-df) that allows a more general consideration of genetic effects. Twenty-three loci were found to be genome-wide significantly associated (Bonferroni corrected P ≤ 2.19 × 10−12) with at least one metabolite or ratio. For five of them, we show the evidence of nonadditive effects. We replicated 17 loci, including 3 loci with nonadditive effects, in an independent study (TwinsUK, N = 846). In conclusion, we found that most genetic effects on metabolite concentrations and ratios were indeed additive, which verifies the practice of using the additive model for analyzing SNP effects on metabolites. 相似文献
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Swati Dey Justin A. North Jaya Sriram Bradley S. Evans F. Robert Tabita 《The Journal of biological chemistry》2015,290(52):30658-30668
All organisms possess fundamental metabolic pathways to ensure that needed carbon and sulfur compounds are provided to the cell in the proper chemical form and oxidation state. For most organisms capable of using CO2 as sole source of carbon, ribulose-1,5-bisphosphate (RuBP) carboxylase/oxygenase (Rubisco) catalyzes primary carbon dioxide assimilation. In addition, sulfur salvage pathways are necessary to ensure that key sulfur-containing compounds are both available and, where necessary, detoxified in the cell. Using knock-out mutations and metabolomics in the bacterium Rhodospirillum rubrum, we show here that Rubisco concurrently catalyzes key and essential reactions for seemingly unrelated but physiologically essential central carbon and sulfur salvage metabolic pathways of the cell. In this study, complementation and mutagenesis studies indicated that representatives of all known extant functional Rubisco forms found in nature are capable of simultaneously catalyzing reactions required for both CO2-dependent growth as well as growth using 5-methylthioadenosine as sole sulfur source under anaerobic photosynthetic conditions. Moreover, specific inactivation of the CO2 fixation reaction did not affect the ability of Rubisco to support anaerobic 5-methylthioadenosine metabolism, suggesting that the active site of Rubisco has evolved to ensure that this enzyme maintains both key functions. Thus, despite the coevolution of both functions, the active site of this protein may be differentially modified to affect only one of its key functions. 相似文献
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为了准确鉴定光合蓝细菌中的各种代谢物,需要对基于液相色谱–质谱联用仪(LC-MS)的代谢组学分析方法进行有针对性的优化。本研究选取了24种涉及中心碳代谢和能量代谢的代谢物作为LC-MS的检测目标,获得了每个代谢物的最适色谱分离条件和质谱参数;同时以光合蓝细菌Synechocystis sp.PCC6803为主要对象,针对性地优化了样品前处理条件,结果显示适当延长梯度洗脱顺序表的时间并将流速设为0.2 m L/min可以得到最佳的分离效果,同时选择80%(V/V)甲醇(-80?C)作为代谢物萃取剂。分析结果证明这一代谢组分析技术可以成功地应用到光合蓝细菌的研究中。 相似文献
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Warming and drought differentially influence the production and resorption of elemental and metabolic nitrogen pools in Quercus rubra 下载免费PDF全文
Vidya Suseela Nishanth Tharayil Baoshan Xing Jeffrey S. Dukes 《Global Change Biology》2015,21(11):4177-4195
The process of nutrient retranslocation from plant leaves during senescence subsequently affects both plant growth and soil nutrient cycling; changes in either of these could potentially feed back to climate change. Although elemental nutrient resorption has been shown to respond modestly to temperature and precipitation, we know remarkably little about the influence of increasing intensities of drought and warming on the resorption of different classes of plant metabolites. We studied the effect of warming and altered precipitation on the production and resorption of metabolites in Quercus rubra. The combination of warming and drought produced a higher abundance of compounds that can help to mitigate climatic stress by functioning as osmoregulators and antioxidants, including important intermediaries of the tricarboxylic acid (TCA) cycle, amino acids including proline and citrulline, and polyamines such as putrescine. Resorption efficiencies (REs) of extractable metabolites surprisingly had opposite responses to drought and warming; drought treatments generally increased RE of metabolites compared to ambient and wet treatments, while warming decreased RE. However, RE of total N differed markedly from that of extractable metabolites such as amino acids; for instance, droughted plants resorbed a smaller fraction of elemental N from their leaves than plants exposed to the ambient control. In contrast, plants in drought treatment resorbed amino acids more efficiently (>90%) than those in ambient (65–77%) or wet (42–58%) treatments. Across the climate treatments, the RE of elemental N correlated negatively with tissue tannin concentration, indicating that polyphenols produced in leaves under climatic stress could interfere with N resorption. Thus, senesced leaves from drier conditions might have a lower nutritive value to soil heterotrophs during the initial stages of litter decomposition despite a higher elemental N content of these tissues. Our results suggest that N resorption may be controlled not only by plant demand, but also by climatic influences on the production and resorption of plant metabolites. As climate–carbon models incorporate increasingly sophisticated nutrient cycles, these results highlight the need to adequately understand plant physiological responses to climatic variables. 相似文献
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