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981.
982.
Yonathan Uriel Regine Gries Loma Tu Cassandra Carroll Huimin Zhai Margo Moore Gerhard Gries 《Insect Science》2020,27(2):256-265
We tested the recent hypothesis that the"fly factor"phenomenon(food cur-rently or previously fed on by flies attracts more flies than the same type of food kept inccessible to flies)is mediated by bacterial symbionts deposited with feees or regur-gitated by feeding flies.We allowed laboratory-reared black blow flies,Phormia regina(Meigen),to feed and de fecate on bacterial Luria-Bertani medium solidified with agar,and isolated seven morphologically distinct bacterial colonies.We identified these us-ing matrix-assisted laser desorption/ionization mass spectrometry and sequencing of the 165 rRNA gene.In two-choice laboratory experiments,traps baited with cultures of Pro-teus mirabilis Hauser,Morganella morganii subsp.sibonii Jensen,or Serratia marcescens Bizio,captured significantly more flies than corresponding control jars baited with tryptic soy agar only.A mixture of seven bacterial strains as a trap bait was more attractive to flies than a single bacterial isolate(M.m.siboni).In a field experiment,traps baited with agar cultures of P:mirabilis and M.m siboni in combination captured significantly more flies than lraps baited with either bacterial isolate alone or the agar control.As evident by gas chromatography-mass spectrometry,the odor profiles of bacterial isolates differ,which may explain the additive effect of bacteria to the attractiveness of bacterial trap baits.As"generalist bacteria,"P mirabilis and M.m.sibonii growing on animal protein(beef liver)or plant protein(tofu)are similarly effective in attracting flies.Bacteria-derived airborne semiochemicals appear to mediate foraging by flies and to inform their feeding and oviposition decisions. 相似文献
983.
Optimization and performance validation for the fully automatic
blood type analysis system 下载免费PDF全文
Rongrong Pang Libo Zhang Yong Wang Wenping Han Min Huang Qiang Fu 《Asia-Pacific Journal of Blood Types and Genes》2019,3(1):67-72
To evaluate and validate the application of fully automatic blood type analysis system parameters under actual lab conditions. All key system parameters were optimized and validated accordingly. The optimized parameters were centrifugal speed at 550 rpm; centrifugal time 20 min; resuspension speed 1,200 rpm; resuspension time: 45 s; incubation temperature 25℃ ; incubation time 400 s; incubation rate: 0 rpm. The sampled red blood cell concentration was 3%. The ratio of plasma to red blood cells reagent was 60 μL:30 μL; the ratio of antibody (reagent) to sampled diluted red blood cell was 30 μL:30 μL. After applying our key parameters for optimization and validation, the automatic blood type detection system''s performance was found to meet the relevant requirements, effectively improving the accuracy and reliability of the detection system. 相似文献
984.
Lintong Hu Lanlan Xue Jinzhou Fu Ping Xiao Tianyou Zhai Huiqiao Li 《Liver Transplantation》2020,10(36)
Asymmetric supercapacitors (ASCs) with high theoretical energy density have attracted extensive attention during the past years. However, the huge capacity gap between the two electrodes greatly limits high energy density. Regulating electrode mass can make the capacity balanced, while sacrificing weight and volume. Herein, a soluble bipolar molecule, 4‐hydroxy‐2,2,6,6‐tetramethylpiperidinyloxyl (4‐OH‐TEMPO), is proposed as a versatile mediator in the electrolyte to balance the capacity gap in different types of ASCs. 4‐OH‐TEMPO is able to quickly obtain or lose electrons at different potentials regardless of the pH values, thus can contribute large redox capacity at the interface of capacitive electrode in ASCs in both positive or negative electrodes, acidic or alkaline systems. A case study of two typical ACSs is presented, Zn//activated carbon (AC) system with 4‐OH‐TEMPO for positive electrode enhancement in a mildly acidic electrolyte and AC//Ni(OH)2 system with 4‐OH‐TEMPO for negative electrode enhancement in an alkaline electrolyte. Both demonstrate that the addition of 4‐OH‐TEMPO can effectively balance the capacity mismatching between two electrodes, and its capacity contribution can be adjusted by concentration. The energy density of the two ACSs with 4‐OH‐TEMPO can be greatly promoted without significant sacrifice of the device's volume or mass. 相似文献
985.
Ping Wang Weidong Li Bo Zhai Xian Jiang Hongchi Jiang Chunlong Zhang Xueying Sun 《Journal of cellular biochemistry》2020,121(5-6):3090-3098
Pancreatic cancer is a malignancy of the digestive system characterized by poor prognosis. A number of prognostic messenger RNA (mRNA) signatures have been identified by using the high-throughput expression profiles. MicroRNAs (miRNA) play a critical role in regulating multiple cellular functions. However, no such integrated analysis of miRNAs and mRNAs for studying the prognostic mechanisms of pancreatic cancer has been reported. In this study, we first identified prognostic mRNAs and miRNAs based on The Cancer Genome Atlas datasets, and then performed an enrichment analysis to explore the underlying biological mechanisms involved in pancreatic cancer prognosis at the mRNA level. Furthermore, we performed an integrated analysis of mRNAs and miRNAs to identify prognostic subpathways, which were closely associated with pancreatic cancer genes and tumor hallmarks and involved in hypoxia, oxidative phosphyorylation and xenobiotic metabolisms. Meanwhile, we performed a random walk algorithm based on global network, prognostic mRNAs and miRNAs, and identified top risk mRNAs as the prognostic signature. Finally, an independent testing set was used to confirm the predictive power of the top mRNA signature, and most of these genes involved were known oncogenes. In conclusion, we performed a series of integrated analyses by comprehensively exploring pancreatic cancer prognosis and systematically optimized the prognostic signature for clinical use. 相似文献
986.
987.
Min Zhang Yu Xiao Rongrong Zhu Qin Zhang Shi-Long Wang 《Bioprocess and biosystems engineering》2012,35(9):1455-1465
To increase thermotolerance and ethanol tolerance in Saccharomyces cerevisiae strain YZ1, the strategies of high-energy pulse electron beam (HEPE) and three rounds of protoplast fusion were explored. The YF31 strain had the characteristics of resistant to high-temperature, high-ethanol tolerance, rapid growth and high yield. The YF31 could grow on plate cultures up to 47?°C, containing 237.5?g?L?1 of ethanol. In particular, the mutant strain YF31 generated 94.2?±?4.8?g?L?1 ethanol from 200?g glucose L?1 at 42?°C, which was 2.48 times the production of the wild strain YZ1. Results demonstrated that the variant phenotypes from the strains screening by HEPE irradiation could be used as parent stock for yeast regeneration and the protoplast fusion technology is sufficiently powerful in combining suitable characteristics in a single strain for ethanol fermentation. 相似文献
988.
Min Fengling Liu Fenju Wen Wanxin Zhai Lijia Tong Jiandong Wang Zu Yuan Xin Gao Qingxiang 《Radiation and environmental biophysics》2009,48(4):371-378
Clinical trials with rituximab in combination with chemotherapeutic regimens have shown promising results. Data on the effects
of rituximab treatment in combination with irradiation are, however, limited and inconsistent. This study aims to investigate
the effects of rituximab (R) on cell death induced by X-irradiation in Raji lymphoma cells and to evaluate its mechanisms.
We found the cell growth inhibition by irradiation was enhanced by additional rituximab exposure both in cells precultured
with rituximab followed by irradiation (R + irradiation) or in cells treated in the reverse sequence (irradiation + R). R + irradiation
combination treatment induced more apoptotic cells than irradiation and irradiation + R treatment as early as 12 h after treatment.
At 24 h, both combination treatments, R + irradiation and irradiation + R, showed apoptotic cells, which were significantly
different from irradiation alone. G2/M cell cycle arrest was observed after irradiation alone and the combination treatment.
The combination treatment revealed an elevation in reactive oxygen species (ROS) generation in a radiation dose-dependent
manner. In addition, rituximab enhanced the cell growth inhibition and apoptotic cell death induced by the oxidative agent,
H2O2. We propose that rituximab mediates a significant in vitro radiosensitizing effect and induces cell cycle changes and apoptosis
in Raji cells. ROS probably play an important role in these events. 相似文献
989.
Jinzhong Wan Die Meng Tao Long Rongrong Ying Mao Ye Shengtian Zhang Qun Li Yan Zhou Yusuo Lin 《PloS one》2015,10(6)
This study investigated the performance of rhamnolipids-citric acid mixed agents in simultaneous desorption of lindane and heavy metals from soils. The capacity of the mixed agents to solubilize lindane, lead and cadmium in aqueous solution was also explored. The results showed that the presence of citric acid greatly enhanced the solubilization of lindane and cadmium by rhamnolipids. A combined effect of the mixed agents on lindane and heavy metals removal from soils was observed. The maximum desorption ratios for lindane, cadmium and lead were 85.4%, 76.4% and 28.1%, respectively, for the mixed agents containing 1% rhamnolipidsand 0.1 mol/L citric acid. The results also suggest that the removal efficiencies of lead and cadmium were strongly related to their speciations in soils, and metals in the exchangeable and carbonate forms were easier to be removed. Our study suggests that the combining use of rhamnolipids and citric acid is a promising alternative to simultaneously remove organochlorine pesticides and heavy metals from soils. 相似文献
990.