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991.
992.
993.
Haegyeom Kim Min‐Young Cho Mok‐Hwa Kim Kyu‐Young Park Hyeokjo Gwon Yunsung Lee Kwang Chul Roh Kisuk Kang 《Liver Transplantation》2013,3(11):1500-1506
A hybrid supercapacitor with high energy and power densities is reported. It comprises a composite anode of anatase TiO2 and reduced graphene oxide and an activated carbon cathode in a non‐aqueous electrolyte. While intercalation compounds can provide high energy typically at the expense of power, the anatase TiO2 nanoparticles are able to sustain both high energy and power in the hybrid supercapacitor. At a voltage range from 1.0 to 3.0 V, 42 W h kg?1 of energy is achieved at 800 W kg?1. Even at a 4‐s charge/discharge rate, an energy density as high as 8.9 W h kg?1 can be retained. The high energy and power of this hybrid supercapacitor bridges the gap between conventional batteries with high energy and low power and supercapacitors with high power and low energy. 相似文献
994.
Yu‐Sin Jang Alok Malaviya Joungmin Lee Jung Ae Im Sang Yup Lee Julia Lee Moon‐Ho Eom Jung‐Hee Cho Do Young Seung 《Biotechnology progress》2013,29(4):1083-1088
Butanol is considered as a superior biofuel, which is conventionally produced by clostridial acetone‐butanol‐ethanol (ABE) fermentation. Among ABE, only butanol and ethanol can be used as fuel alternatives. Coproduction of acetone thus causes lower yield of fuel alcohols. Thus, this study aimed at developing an improved Clostridium acetobutylicum strain possessing enhanced fuel alcohol production capability. For this, we previously developed a hyper ABE producing BKM19 strain was further engineered to convert acetone into isopropanol. The BKM19 strain was transformed with the plasmid pIPA100 containing the sadh (primary/secondary alcohol dehydrogenase) and hydG (putative electron transfer protein) genes from the Clostridium beijerinckii NRRL B593 cloned under the control of the thiolase promoter. The resulting BKM19 (pIPA100) strain produced 27.9 g/l isopropanol‐butanol‐ethanol (IBE) as a fuel alcohols with negligible amount of acetone (0.4 g/l) from 97.8 g/l glucose in lab‐scale (2 l) batch fermentation. Thus, this metabolically engineered strain was able to produce 99% of total solvent produced as fuel alcohols. The scalability and stability of BKM19 (pIPA100) were evaluated at 200 l pilot‐scale fermentation, which showed that the fuel alcohol yield could be improved to 0.37 g/g as compared to 0.29 g/g obtained at lab‐scale fermentation, while attaining a similar titer. To the best of our knowledge, this is the highest titer of IBE achieved and the first report on the large scale fermentation of C. acetobutylicum for IBE production. © 2013 American Institute of Chemical Engineers Biotechnol. Prog., 29:1083–1088, 2013 相似文献
995.
Although Aurora B is important in cleavage furrow ingression and completion during cytokinesis, the mechanism by which kinase activity is targeted to the cleavage furrow and the molecule(s) responsible for this process have remained elusive. Here, we demonstrate that an essential mitotic kinesin MKlp2 requires myosin-II for its localization to the equatorial cortex, and this event is required to recruit Aurora B to the equatorial cortex in mammalian cells. This recruitment event is also required to promote the highly focused accumulation of active RhoA at the equatorial cortex and stable ingression of the cleavage furrow in bipolar cytokinesis. Specifically, in drug-induced monopolar cytokinesis, targeting Aurora B to the cell cortex by MKlp2 is essential for cell polarization and furrow formation. Once the furrow has formed, MKlp2 further recruits Aurora B to the growing furrow. This process together with continuous Aurora B kinase activity at the growing furrow is essential for stable furrow propagation and completion. In contrast, a MKlp2 mutant defective in binding myosin-II does not recruit Aurora B to the cell cortex and does not promote furrow formation during monopolar cytokinesis. This mutant is also defective in maintaining the ingressing furrow during bipolar cytokinesis. Together, these findings reveal that targeting Aurora B to the cell cortex (or the equatorial cortex) by MKlp2 is essential for the maintenance of the ingressing furrow for successful cytokinesis. 相似文献
996.
Na Na Kim Hyun Suk Shin Young Jae Choi Yuzo Yamamoto Kosuke Fukaya Hiroshi Ueda 《Marine and Freshwater Behaviour and Physiology》2013,45(6):397-410
Migrating fish such as salmonids are affected by external environmental factors and salinity changes are particularly important, influencing spawning migration. The aim of this study was to test whether changes in salinity would affect the expression of the hypothalamic-pituitary-gonadal (HPG) axis hormones (gonadotropin-releasing hormones (GnRHs) [salmon GnRH and chicken GnRH-II], GnRH receptors [GnRHR1 and GnRHR5], and mRNA of the gonadotropin hormone [GTH] subunits [GTHα, follicle stimulating hormone β, and luteinizing hormone β]) in chum salmon (Oncorhynchus keta). Fish were progressively transferred from seawater (SW) through 50% SW to freshwater (FW), and the relationship between the osmoregulatory hormone prolactin (PRL) and sexual maturation was determined. The expression and activity of HPG hormones and their receptors, and levels of estradiol-17β and PRL increased after fish were transferred to FW, demonstrating that changes in salinity stimulate the HPG axis and PRL production in migrating chum salmon. These findings reveal details about the role of the endocrine system in maintaining homeostasis and stimulating sexual maturation and reproduction in response to salinity changes in this species. 相似文献
997.
Seung Mi Lee Jeong Woo Park Byoung Jae Kim Chan-Wook Park Joong Shin Park Jong Kwan Jun Bo Hyun Yoon 《PloS one》2013,8(12)
Background
The objective of this study was to determine whether acute histologic chorioamnionitis is associated with adverse neonatal outcomes in late preterm infants who were born after preterm PROM.Methodology/Principal Findings
The relationship between the presence of acute histologic chorioamnionitis and adverse neonatal outcome was examined in patients with preterm PROM who delivered singleton preterm newborns between 34 weeks and 36 6/7 weeks of gestation. Nonparametric statistics were used for data analysis. The frequency of acute histologic chorioamnionitis was 24% in patients with preterm PROM who delivered preterm newborns between 34 weeks and 36 6/7 weeks of gestation. Newborns born to mothers with histologic chorioamnionitis had significantly higher rates of adverse neonatal outcome (74% vs 51%; p<0.005) than those without histologic chorioamnionitis. This relationship remained significant after adjustment for gestational age at preterm PROM, gestational age at delivery, and exposure to antenatal corticosteroids.Conclusions/Significance
The presence of acute histologic chorioamnionitis is associated with adverse neonatal outcome in late preterm infants born to mothers with preterm PROM. 相似文献998.
Bridgette M. Dingle Yuying Liu Nicole Y. Fatheree Juleen Min J. Marc Rhoads Dat Q. Tran 《PloS one》2013,8(12)
Necrotizing enterocolitis (NEC) results from severe intestinal inflammation in premature infants. FoxP3+ regulatory T cells (Tregs) are central to gut homeostasis. While Treg proportions are significantly reduced in the ileums of premature infants with NEC, it is unknown whether they play a critical function in preventing NEC. This study investigated Treg development in newborn rat pups and their role in experimental NEC induction. Utilizing an established rat model of experimental NEC, the ontogeny of T cells and Tregs in newborn pups was characterized by flow cytometry. To investigate the functions of Tregs, newborn pups were given Tregs harvested from adult rats prior to NEC induction to assess clinical improvement and mechanisms of immune regulation. The results revealed that there were few Treg numbers in the terminal ileums of newborn rats and 8-fold reduction after NEC. Adoptive transfer of Tregs significantly improved weight loss, survival from 53% to 88%, and NEC incidence from 87% to 35%. The Tregs modulated the immune response as manifested in reduced CD80 expression on antigen presenting cells and decreased T cell activation within the mesenteric lymph nodes. These findings suggest that while Tregs are present in the intestines, their numbers might be insufficient to dampen the excessive inflammatory state in NEC. Adoptive transfer of Tregs attenuates the severity of NEC by limiting the immune response. Strategies to enhance Tregs have a therapeutic potential in controlling the development of NEC. 相似文献
999.
目的:评估自体DC与CIK细胞治疗难治复发急性髓细胞白血病的近期疗效与安全性。方法:给予20例难治复发急性髓细胞白血病患者树突状细胞(DC)与细胞因子诱导的杀伤细胞(CIK)治疗,20例难治复发的应用同样化疗方案的急性髓细胞白血病患者做为对照组;治疗后4周观察两组患者临床疗效和生存质量(KVS)评分,DC与CIK细胞治疗前和治疗后1周检测T细胞亚群(CD3+、CD3+CD4+、CD3+CD8+、CD3+CD56+)和细胞因子(IL-12、IL-2、IL-7、IFN-γ及TNF—α)水平的变化。结果:(1)DC与CIK细胞治疗组有效率和KPS评分明显高于对照组(P〈0.05),所有患者的不良反应轻微,均可耐受。(2)DC与CIK细胞治疗后1周,患者T细胞亚群百分比和细胞因子含量较治疗前均明显升高,其中CD3+、CD3+CD56+及IL-12、IL-7明显升高(P〈0.05)。结论:DC与CIK细胞免疫治疗难治复发急性髓细胞白血病安全有效。 相似文献
1000.
Victor M. Victor Susana Rovira-Llopis Vanessa Saiz-Alarcon Maria C. Sangüesa Luis Rojo-Bofill Celia Ba?uls Rosa Falcón Raquel Castelló Luis Rojo Milagros Rocha Antonio Hernández-Mijares 《PloS one》2014,9(9)