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排序方式: 共有825条查询结果,搜索用时 31 毫秒
141.
Hemme CL Fields MW He Q Deng Y Lin L Tu Q Mouttaki H Zhou A Feng X Zuo Z Ramsay BD He Z Wu L Van Nostrand J Xu J Tang YJ Wiegel J Phelps TJ Zhou J 《Applied and environmental microbiology》2011,77(22):7998-8008
Thermophilic anaerobic noncellulolytic Thermoanaerobacter species are of great biotechnological importance in cellulosic ethanol production due to their ability to produce high ethanol yields by simultaneous fermentation of hexose and pentose. Understanding the genome structure of these species is critical to improving and implementing these bacteria for possible biotechnological use in consolidated bioprocessing schemes (CBP) for cellulosic ethanol production. Here we describe a comparative genome analysis of two ethanologenic bacteria, Thermoanaerobacter sp. X514 and Thermoanaerobacter pseudethanolicus 39E. Compared to 39E, X514 has several unique key characteristics important to cellulosic biotechnology, including additional alcohol dehydrogenases and xylose transporters, modifications to pentose metabolism, and a complete vitamin B12 biosynthesis pathway. Experimental results from growth, metabolic flux, and microarray gene expression analyses support genome sequencing-based predictions which help to explain the distinct differences in ethanol production between these strains. The availability of whole-genome sequence and comparative genomic analyses will aid in engineering and optimizing Thermoanaerobacter strains for viable CBP strategies. 相似文献
142.
Panagiotou V Love KR Jiang B Nett J Stadheim T Love JC 《Applied and environmental microbiology》2011,77(9):3154-3156
The selection of highly productive cell lines remains a key step for manufacturing therapeutic proteins. Microengraving was used to screen chemically mutagenized populations of Pichia pastoris for increased production of an Fc fragment. Clones retrieved following three rounds of mutagenesis yielded titers 2.65-fold greater than those of the parental strain. 相似文献
143.
Patil J Stucki S Nussberger J Schaffner T Gygax S Bohlender J Imboden H 《Regulatory peptides》2011,167(1):31-41
Although the physiological and pharmacological evidences suggest a role for angiotensin II (Ang II) with the mammalian heart, the source and precise location of Ang II are unknown. To visualize and quantitate Ang II in atria, ventricular walls and interventricular septum of the rat and human heart and to explore the feasibility of local Ang II production and function, we investigated by different methods the expression of proteins involved in the generation and function of Ang II. We found mRNA of angiotensinogen (Ang-N), of angiotensin converting enzyme, of the angiotensin type receptors AT(1A) and AT? (AT(1B) not detected) as well as of cathepsin D in any part of the hearts. No renin mRNA was traceable. Ang-N mRNA was visualized by in situ hybridization in atrial ganglial neurons. Ang II and dopamine-β-hydroxylase (DβH) were either colocalized inside the same neuronal cell or the neurons were specialized for Ang II or DβH. Within these neurons, the vesicular acetylcholine transporter (VAChT) was neither colocalized with Ang II nor DβH, but VAChT-staining was found with synapses en passant encircle these neuronal cells. The fibers containing Ang II exhibited with blood vessels and with cardiomyocytes supposedly angiotensinergic synapses en passant. In rat heart, right atrial median Ang II concentration appeared higher than septal and ventricular Ang II. The distinct colocalization of neuronal Ang II with DβH in the heart may indicate that Ang II participates together with norepinephrine in the regulation of cardiac functions: produced as a cardiac neurotransmitter Ang II may have inotropic, chronotropic or dromotropic effects in atria and ventricles and contributes to blood pressure regulation. 相似文献
144.
Ma W Belisle SE Mosier D Li X Stigger-Rosser E Liu Q Qiao C Elder J Webby R Katze MG Richt JA 《Journal of virology》2011,85(22):11626-11637
145.
Volker Lennerz Stefanie Gross Elisa Gallerani Cristiana Sessa Nicolas Mach Steffen Boehm Dagmar Hess Lotta von Boehmer Alexander Knuth Adrian F. Ochsenbein Ulrike Gnad-Vogt Juergen Zieschang Ulf Forssmann Thomas Woelfel Eckhart Kaempgen 《Cancer immunology, immunotherapy : CII》2014,63(4):381-394
Purpose
Survivin is a member of the inhibitor-of-apoptosis family. Essential for tumor cell survival and overexpressed in most cancers, survivin is a promising target for anti-cancer immunotherapy. Immunogenicity has been demonstrated in multiple cancers. Nonetheless, few clinical trials have demonstrated survivin-vaccine-induced immune responses.Experimental design
This phase I trial was conducted to test whether vaccine EMD640744, a cocktail of five HLA class I-binding survivin peptides in Montanide® ISA 51 VG, promotes anti-survivin T-cell responses in patients with solid cancers. The primary objective was to compare immunologic efficacy of EMD640744 at doses of 30, 100, and 300 μg. Secondary objectives included safety, tolerability, and clinical efficacy.Results
In total, 49 patients who received ≥2 EMD640744 injections with available baseline- and ≥1 post-vaccination samples [immunologic-diagnostic (ID)-intention-to-treat] were analyzed by ELISpot- and peptide/MHC-multimer staining, revealing vaccine-activated peptide-specific T-cell responses in 31 patients (63 %). This cohort included the per study protocol relevant ID population for the primary objective, i.e., T-cell responses by ELISpot in 17 weeks following first vaccination, as well as subjects who discontinued the study before week 17 but showed responses to the treatment. No dose-dependent effects were observed. In the majority of patients (61 %), anti-survivin responses were detected only after vaccination, providing evidence for de novo induction. Best overall tumor response was stable disease (28 %). EMD640744 was well tolerated; local injection-site reactions constituted the most frequent adverse event.Conclusions
Vaccination with EMD640744 elicited T-cell responses against survivin peptides in the majority of patients, demonstrating the immunologic efficacy of EMD640744. 相似文献146.
147.
Sabrina Backhaus Juergen Kreyling Kerstin Grant Carl Beierkuhnlein Julia Walter Anke Jentsch 《Ecosystems》2014,17(6):1068-1081
The frequency and magnitude of extreme weather events such as drought are expected to increase in the future. At present, plant responses to recurrent extreme events have been sparsely examined and the role of stress history on subsequent stress response has been widely neglected. In a long-term field experiment, we investigated the response of grassland and heath communities to a very severe drought event, which exceeded the duration of projected drought scenarios. During the preceding 6 years, the plant communities experienced scenarios of varying water supply, including annually recurring drought, heavy rain, regular watering, and natural drought periods. Single species and plant communities that were regularly watered in the preceding years revealed the highest tissue die-back under a very severe drought when compared to plants that experienced mild or severe drought stress before. Contrary to expectations, the root to shoot ratio did not increase due to previous recurrent drought occurrences. Furthermore, pre-exposure effects on Vaccinium myrtillus and Plantago lanceolata tissue die-back and reproductive biomass (P. lanceolata) were altered by community composition. Recurrent mild drought stress seems to improve drought resistance of plant communities and species. Potential reasons could be epigenetic changes or soil biotic legacies. Morphological legacies such as altered root to shoot ratio did not play a role in our study. Imprinting events which trigger this ecological stress memory do not have to be extreme themselves. Thresholds, longevity of effects, and the role of biodiversity shown by the importance of community composition require further attention. 相似文献
148.
Both functional and also more recently resting state magnetic resonance imaging have become established tools to investigate functional brain networks. Most studies use these tools to compare different populations without controlling for potential differences in underlying brain structure which might affect the functional measurements of interest. Here, we adapt a simulation approach combined with evaluation of real resting state magnetic resonance imaging data to investigate the potential impact of partial volume effects on established functional and resting state magnetic resonance imaging analyses. We demonstrate that differences in the underlying structure lead to a significant increase in detected functional differences in both types of analyses. Largest increases in functional differences are observed for highest signal-to-noise ratios and when signal with the lowest amount of partial volume effects is compared to any other partial volume effect constellation. In real data, structural information explains about 25% of within-subject variance observed in degree centrality – an established resting state connectivity measurement. Controlling this measurement for structural information can substantially alter correlational maps obtained in group analyses. Our results question current approaches of evaluating these measurements in diseased population with known structural changes without controlling for potential differences in these measurements. 相似文献
149.
Hans J. De Boeck Juliette M. G. Bloor Rien Aerts Michael Bahn Claus Beier Bridget A. Emmett Marc Estiarte Jos M. Grünzweig Aud H. Halbritter Petr Holub Anke Jentsch Karel Klem Juergen Kreyling Gyrgy Krel‐Dulay Klaus Steenberg Larsen Alexandru Milcu Jacques Roy Bjarni D. Sigurdsson Melinda D. Smith Marcelo Sternberg Vigdis Vandvik Thomas Wohlgemuth Ivan Nijs Alan K. Knapp 《Global Change Biology》2020,26(2):e6-e7
150.
Taube A Schlich R Sell H Eckardt K Eckel J 《American journal of physiology. Heart and circulatory physiology》2012,302(11):H2148-H2165
Abdominal obesity is a major risk factor for cardiovascular disease, and recent studies highlight a key role of adipose tissue dysfunction, inflammation, and aberrant adipokine release in this process. An increased demand for lipid storage results in both hyperplasia and hypertrophy, finally leading to chronic inflammation, hypoxia, and a phenotypic change of the cellular components of adipose tissue, collectively leading to a substantially altered secretory output of adipose tissue. In this review we have assessed the adipo-vascular axis, and an overview of adipokines associated with cardiovascular disease is provided. This resulted in a first list of more than 30 adipokines. A deeper analysis only considered adipokines that have been reported to impact on inflammation and NF-κB activation in the vasculature. Out of these, the most prominent link to cardiovascular disease was found for leptin, TNF-α, adipocyte fatty acid-binding protein, interleukins, and several novel adipokines such as lipocalin-2 and pigment epithelium-derived factor. Future work will need to address the potential role of these molecules as biomarkers and/or drug targets. 相似文献