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231.
目的:探讨地高辛片对老年慢性心力衰竭患者血清血清糖类抗原(CA125)、心钠肽(ANP)、脑钠肽(BNP)、基质金属蛋白酶9(MMP-9)及金属蛋白酶组织抑制剂(TIMP-1)水平的影响。方法:收集我院老年慢性心力衰竭患者100例,随机分为对照组和实验组,每组各50例,对照组患者给予常规治疗,实验组患者在对照组的基础上给予地高辛片。比较治疗前后两组患者血清糖类抗原(CA125)、心钠肽(ANP)、脑钠肽(BNP)、基质金属蛋白酶9(MMP-9)及金属蛋白酶组织抑制剂(TIMP-1)水平。结果:与治疗前相比,两组患者血清CA125、ANP、BNP及MMP-9水平降低,TIMP-1水平升高(P0.05);治疗后与对照组相比,实验组CA125水平(34.05±4.63)较低,ANP水平较低(216.98±27.65),BNP水平较低(437.62±45.26),MMP-9水平较低(550.17±65.15),TIMP-1水平较高(182.32±21.78)(P0.05)。结论:地高辛片能够改善老年慢性心力衰竭患者心肌功能,推测其机制可能与降低血清CA125、ANP、BNP、MMP-9水平,升高TIMP-1水平有关。 相似文献
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Joseph K. Cheng Amanda M. Lewis Do Soon Kim Timothy Dyess Hal S. Alper 《Biotechnology journal》2016,11(8):1100-1109
Mammalian cell line development requires streamlined methodologies that will reduce both the cost and time to identify candidate cell lines. Improvements in site‐specific genomic editing techniques can result in flexible, predictable, and robust cell line engineering. However, an outstanding question in the field is the specific site of integration. Here, we seek to identify productive loci within the human genome that will result in stable, high expression of heterologous DNA. Using an unbiased, random integration approach and a green fluorescent reporter construct, we identify ten single‐integrant, recombinant human cell lines that exhibit stable, high‐level expression. From these cell lines, eight unique corresponding integration loci were identified. These loci are concentrated in non‐protein coding regions or intronic regions of protein coding genes. Expression mapping of the surrounding genes reveals minimal disruption of endogenous gene expression. Finally, we demonstrate that targeted de novo integration at one of the identified loci, the 12th exon‐intron region of the GRIK1 gene on chromosome 21, results in superior expression and stability compared to the standard, illegitimate integration approach at levels approaching 4‐fold. The information identified here along with recent advances in site‐specific genomic editing techniques can lead to expedited cell line development. 相似文献
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Dominique T. Monteil Xiao Shen Giulia Tontodonati Lucia Baldi David L. Hacker Florian M. Wurm 《Analytical biochemistry》2016
Disposable orbitally shaken TubeSpin bioreactor 600 tubes (TS600s) were recently developed for the bench-scale cultivation of animal cells in suspension. Here we compared batch cultures of Sf9 insect cells in TS600s, spinner flasks, and shake flasks. Superior cell growth was observed in TS600s and shake flasks as compared with spinner flasks, and more favorable oxygen-enriched cell culture conditions were observed in TS600s as compared with either spinner or shake flasks. The results demonstrated the suitability of TS600s as a disposable vessel for the cultivation of Sf9 cells in suspension. 相似文献
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The immune systems of bacteria and important applications in biotechnology and medicine At the end of the 70s of the last century, a new technique has been developed allowing the synthesis of genes and the inducible expression of their recombinant proteins using restriction enzymes and vectors, mainly plasmids. This era has been designated as genetic engineering and is being replenished by the CRISPR‐Cas9 technology know as genome editing. This technology is about to revolutionize alterations in the genomes of all types of organisms, including bacteria, fungi, plants, animals and even humans. It allows the introduction and elimination of point mutations and even whole genes in all organisms. Important goals are the genetic optimization of crop plants and animals, fighting against cancer in humans and elimination of human viruses and pathogenic multi‐resistant bacteria. Important drawbacks are OFF‐targets which can cause mutations in any gene or influence their expression. 相似文献
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Meisha Holloway‐Phillips Lucas A. Cernusak Margaret Barbour Xin Song Alexander Cheesman Niels Munksgaard Hilary Stuart‐Williams Graham D. Farquhar 《Plant, cell & environment》2016,39(11):2414-2427
The process of evaporation results in the fractionation of water isotopes such that the lighter 16O isotope preferentially escapes the gas phase leaving the heavier 18O isotope to accumulate at the sites of evaporation. This applies to transpiration from a leaf with the degree of fractionation dependent on a number of environmental and physiological factors that are well understood. Nevertheless, the 18O enrichment of bulk leaf water is often less than that predicted for the sites of evaporation. The advection of less enriched water in the transpiration stream has been suggested to limit the back diffusion of enriched evaporative site water (Péclet effect); however, evidence for this effect has been varied. In sampling across a range of species with different vein densities and saturated water contents, we demonstrate the importance of accounting for the relative ‘pool’ sizes of the vascular and mesophyll water for the interpretation of a Péclet effect. Further, we provide strong evidence for a Péclet signal within the xylem that if unaccounted for can lead to confounding of the estimated enrichment within the mesophyll water. This has important implications for understanding variation in the effective path length of the mesophyll and hence potentially the δ18O of organic matter. 相似文献