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91.
Jia Jia Hongmei Yu Xueqiang Gao Jun Chi Yachao Zeng Bowen Qin Dewei Yao Wei Song Zhigang Shao Baolian Yi 《RSC advances》2018,8(23):12887
A novel cathode architecture using vertically aligned Co nanoneedle arrays as an ordered support for application in alkaline anion-exchange membrane fuel cells (AAEMFCs) has been developed. The Co nanoneedle arrays were directly grown on a stainless steel sheet via a hydrothermal reaction and then a Pd layer was deposited on the surface of the Co nanoneedle arrays using a vacuum sputter-deposition method to form Pd/Co nanoneedle arrays. After transferring the Pd/Co nanoneedle arrays to an AAEM, a cathode catalyst layer was formed. Without the use of an alkaline ionomer, the AAEMFC with the prepared cathode catalyst layer showed an enhanced performance with ultra-low Pd loading of down to 33.5 μg cm−2, which is much higher than the conventionally used cathode electrode with a Pt loading of 100 μg cm−2. This is the first report where three-dimensional Co nanoneedle arrays have been used as the cathode support in an AAEMFC, which is able to deliver a higher power density without an alkaline ionomer than that of conventional membrane electrode assembly (MEA).A novel ordered Pd/Co nanoneedle array was used as a cathode in an AAEMFC and delivered a higher power density than that of conventional MEA. 相似文献
92.
Stephanie M. Lim Aaron C. Brault Geert van Amerongen Angela M. Bosco-Lauth Hannah Romo Varsha D. Sewbalaksing Richard A. Bowen Albert D.M.E. Osterhaus Penelope Koraka Byron E.E. Martina 《Emerging infectious diseases》2015,21(8):1357-1365
West Nile virus (WNV) outbreaks in North America have been characterized by substantial die-offs of American crows (Corvus brachyrhynchos). In contrast, a low incidence of bird deaths has been observed during WNV epidemic activity in Europe. To examine the susceptibility of the western European counterpart of American crows, we inoculated carrion crows (Corvus corone) with WNV strains isolated in Greece (Gr-10), Italy (FIN and Ita09), and Hungary (578/10) and with the highly virulent North American genotype strain (NY99). We also inoculated American crows with a selection of these strains to examine the strains’ virulence in a highly susceptible bird species. Infection with all strains, except WNV FIN, resulted in high rates of death and high-level viremia in both bird species and virus dissemination to several organs. These results suggest that carrion crows are highly susceptible to WNV and may potentially be useful as part of dead bird surveillance for early warning of WNV activity in Europe. 相似文献
93.
G G Clark C H Calisher C L Crabbs K M Canestorp R B Tesh R A Bowen D E Taylor 《The American journal of tropical medicine and hygiene》1988,39(6):586-592
Two virus isolates, 1 each from Aedes campestris and Psorophora signipennis mosquitoes collected in south central New Mexico in August 1985, were shown by neutralization tests to be identical to each other, but not to any of more than 250 arthropod-borne and other viruses. Electron microscopy of 1 isolate (85-488NM, chosen as the prototype) indicated that this strain shares morphologic characteristics with viruses of the family Rhabdoviridae. Indirect fluorescent antibody tests indicated that this virus is a member of the genus Vesiculovirus, but is not closely related to any of the North American or other rhabdoviruses with which it was tested, including vesicular stomatitis (Indiana) and vesicular stomatitis (New Jersey) viruses. The name Malpais Spring virus is proposed for this newly recognized vesiculovirus. A serologic survey indicated that Malpais Spring virus infects indigenous (mule deer and pronghorn) and exotic (gemsbok) ungulates at and near the sites where the mosquitoes from which the virus strains were isolated were collected. Antibody prevalence in wild animals indicates that the pronghorn and gemsbok may play roles as hosts for Malpais Spring, epizootic hemorrhagic disease (New Jersey), and bluetongue viruses in this area. 相似文献
94.
95.
Oral acyclovir to suppress recurring herpes simplex virus infections in immunodeficient patients 总被引:4,自引:0,他引:4
S E Straus M Seidlin H Takiff D Jacobs D Bowen H A Smith 《Annals of internal medicine》1984,100(4):522-524
Thirty-two episodes of herpes simplex virus infection in four immunodeficient patients with frequent recurrences were successfully treated with oral acyclovir, one capsule five times a day for 5 days. In 23 of these episodes, the treatments were extended for 1 to 6 months using two to five capsules a day with the aim of suppressing expected recurrences. In these patients, who routinely had more than one recurrence per month before treatment, there were only six outbreaks during more than 60 patient-months of suppressive therapy. Infection always recurred after treatments were completed, but the time to recurrence was shorter after treatments with two acyclovir capsules per day than after treatments with five capsules per day (p less than 0.001). 相似文献
96.
P A Bowen S A Lobel R J Caruana M S Leffell M A House J P Rissing A L Humphries 《Annals of internal medicine》1988,108(1):46-48
The human immunodeficiency virus (HIV) was transmitted to a patient who received a cadaveric renal transplant from a donor who had received massive blood component replacement. A negative HIV antibody test was obtained on serum drawn immediately after transfusion. After transplantation, pretransfusion sera and sera obtained several hours after transfusion tested positive for HIV antibody, suggesting that transfusions had transiently diluted the patient's serum and resulted in a false-negative HIV antibody test. Immediately after transplantation, the recipient showed a transient increase in HIV antigen levels followed by a more sustained increase representing de-novo antigen synthesis. Antibodies to HIV were detected 51 days after transplant. The recipient has shown no signs or symptoms of HIV infection after 1 year. In potential cadaveric organ donors, HIV antibody testing should be performed on pretransfusion sera or on sera obtained several hours after massive transfusion of blood products. 相似文献
97.
The mechanisms underlying the impaired utilization of transferrin-bound iron by erythroid cells in the anemia of the Belgrade laboratory rat were investigated using reticulocytes from homozygous anemic animals and transferrin labeled with 59Fe and 125I. The results were compared with those obtained using reticulocytes from phenylhydrazine-treated rats and iron-deficient rats. Each step in the iron uptake mechanism was investigated, ie, transferrin-receptor interaction, transferrin endocytosis, iron release from transferrin, and transferrin exocytosis. Although there were quantitative differences, no fundamental difference was found in any of the abovementioned aspects of cellular function when the reticulocytes from Belgrade rats were compared with those from iron-deficient animals. The basic defect in the Belgrade reticulocytes must therefore reside in subsequent steps in iron uptake, after it is released from transferrin within endocytotic vesicles, ie, in the mechanism by which it is transferred across the lining membrane of the vesicles into the cell cytosol. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) of reticulocyte ghosts extracts demonstrated a prominent protein band of mol wt 69,000 that was absent or present only in low concentration extracts from the other two types of reticulocytes. This may be a result of the genetic defect. 相似文献
98.
OBJECTIVE: To compare the effects two high-protein (HP) diets that differ in dietary calcium and protein source on weight loss, body composition, glucose and lipid metabolism, markers of liver function, fibrinolysis and endothelial function and blood pressure. DESIGN: Randomized, parallel study (12 wk of energy restriction, 4 wk of energy balance) of high dairy protein/high-calcium (DP, 2400 mg Ca/d) and high mixed protein/moderate calcium (MP, 500 mg Ca/d) diets (5.5 MJ/d, 34% protein, 41% carbohydrate, 24% fat). SUBJECTS: In all, 50 healthy, overweight (age 25-64 y; body mass index 25-35 kg/m(2);) males (n=20) and females (n=30). RESULTS: Loss of total weight (-9.7+/-3.8 kg), fat mass (-8.3+/-0.4 kg) and lean mass (-1.6+/-0.3 kg) were independent of dietary group. Improvements in fasting insulin, lipids, systolic/diastolic blood pressure, and markers of liver function, fibrinolysis and endothelial function were independent of dietary intervention. CONCLUSIONS: Increased dietary calcium/dairy foods in an energy-restricted, HP diet does not affect weight loss or body composition. Weight reduction following increased protein diets is associated with beneficial metabolic outcomes that are not affected by protein source. 相似文献
99.
100.