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11.
Enzyme(s) capable of decomposing N-acetylglucosaminyl ribitol teichoic acid prepared from the cell wall of Staphylococcus aureus FDA 209 P was obtained from the culture supernatant of a gram-negative, rod-shaped, spore-forming soil bacterium. Properties of the bacterium were very similar to those of Bacillus circulans. 相似文献
12.
A surgical technique for secondary emplacement of an orbital implant is described in which a spherical implant encased in a scleral homograft is placed in the orbit through a transconjuctival incision and sutured to the superior part of the periosteum. 相似文献
13.
The role of cholecystostomy in the sugical treatment of gallstones has been considered. In a consecutive series of 558 patients who underwent surgery for gallstones, 30 (5-4 per cent) had cholecystostomy alone and a further 17 (3-1 per cent) cholecystostomy combined with exploration of the bile ducts. Cholecystostomy was done because cholecystectomy was technically very hazardous in 15 patients. In the remaining patients cholecystostomy was preferred to cholecystectomy because o f the poor general condition of the patient or the presence of pancreatitis. Of the 47 patients submitted to cholecystostomy, 2(4-2 per cent) died postoeratively and 4(8-4 percent) subsequently underwent cholecystectomy. Of 24 patients who were available for long term follow-up, only 1 patient had pain which was definitely considered to be due to gallstones, although 3 other patients also had abdominal pain, while 7 patients showed radiological evidience of gallstones. It is contended that cholecystostomy has a small but definite part to play in the immediate surgical treatment of gallstones and that the long term results of the operation are sufficiently good to justify its use in selected patients. 相似文献
14.
Marla Luther John Parry Jeffrey Moore Jianghong Meng Yifan Zhang Zhihong Cheng Liangli Yu 《Food chemistry》2007,104(3):1065-1073
Ethanol extracts of Chardonnay grape and black raspberry seed flours were evaluated for their capacity to suppress lipid oxidation, preserve important fatty acids, and inhibit microbial growth. They were also tested for radical scavenging activity against DPPH and peroxyl radicals as reflected in oxygen radical absorbance capacity (ORAC), and total phenolic content (TPC). Both tested seed flour extracts suppressed lipid oxidation and rancidity development in fish oil. Black raspberry seed flour extract significantly reduced the degradation of biologically important n − 3 PUFA under accelerated oxidative conditions. Black raspberry and Chardonnay seed flour extracts at 165 and 160 μg seed flour equivalents/mL, respectively exhibited bacteriocidal activity against Escherichia coli and growth inhibition of Listeria monocytogenes under experimental conditions. Both seed flour extracts exhibited DPPH radical quenching activity and Chardonnay had the stronger ORAC of 663 μmol Trolox equivalents per gram seed flour and the higher TPC of 99 mg gallic acid equivalents/g flour. The data from this study suggest the potential for developing natural food preservatives from these seed flours for improving food stability, quality, safety, and consumer acceptance. 相似文献
15.
Solid lubricant coatings usually fail quite suddenly and thus, for a given specimen, a well-defined life can be measured. Failure may be caused by a number of physical processes, e.g. wearing through the coating, loss of adhesion to the substrate or fatigue. Wear tests of 70 specimens with similarly loaded MoS2 coatings are analysed. The coating life (in cycles) was in general proportional to the thickness and inversely proportional to the load and amplitude, but there was considerable scatter. The results could be expressed in terms of a specific wear rate fitting a mixed Weibull distribution. 相似文献
16.
Tiffany D. Andras Troy S. Alexander Asiri Gahlena R. Mitchell Parry Facundo M. Fernandez Julia Kubanek May D. Wang Mark E. Hay 《Journal of chemical ecology》2012,38(10):1203-1214
Coral reefs are in global decline, with seaweeds increasing as corals decrease. Although seaweeds inhibit coral growth, recruitment, and survivorship, the mechanism of these interactions is poorly understood. Here, we used field experiments to show that contact with four common seaweeds induces bleaching on natural colonies of Porites rus. Controls in contact with inert, plastic mimics of seaweeds did not bleach, suggesting seaweed effects resulted from allelopathy rather than shading, abrasion, or physical contact. Bioassay-guided fractionation of the hydrophobic extract from the red alga Phacelocarpus neurymenioides revealed a previously characterized antibacterial metabolite, neurymenolide A, as the main allelopathic agent. For allelopathy of lipid-soluble metabolites to be effective, the compounds would need to be deployed on algal surfaces where they could transfer to corals on contact. We used desorption electrospray ionization mass spectrometry (DESI-MS) to visualize and quantify neurymenolide A on the surface of P. neurymenioides, and we found the molecule on all surfaces analyzed, with highest concentrations on basal portions of blades. 相似文献
17.
Wai Ling Cheung-Lee Madison E. Parry Dr. Chuhan Zong Alexis Jaramillo Cartagena Prof. Seth A. Darst Prof. Nancy D. Connell Dr. Riccardo Russo Prof. A. James Link 《Chembiochem : a European journal of chemical biology》2020,21(9):1335-1340
We report the heterologous expression, structure, and antimicrobial activity of a lasso peptide, ubonodin, encoded in the genome of Burkholderia ubonensis. The topology of ubonodin is unprecedented amongst lasso peptides, with 18 of its 28 amino acids found in the mechanically bonded loop segment. Ubonodin inhibits RNA polymerase in vitro and has potent antimicrobial activity against several pathogenic members of the Burkholderia genus, most notably B. cepacia and B. multivorans, causative agents of lung infections in cystic fibrosis patients. 相似文献
18.
John W. Parry Zhihong Cheng Jeffrey Moore Liangli Lucy Yu 《Journal of the American Oil Chemists' Society》2008,85(5):457-464
Cold-pressed seed flours from pumpkin, parsley, mullein, cardamom, and milk thistle were examined for total oil, fatty acid
profile of the oil, total phenolic content (TPC), scavenging activities against peroxyl (ORAC), hydroxyl (HOSC) and 2,2-diphenyl-1-picrylhydrazyl
(DPPH) (RDSC) radicals, and antiproliferative capacity against HT-29 human colon cancer cells. The cold-pressed parsley seed
flour contained a very high concentration of total oil—17.6 g/100 g flour—with primarily C18:1 fatty acid at 86.2 g/100 g
fatty acids. All other flour oils had relatively high levels of saturated fats, ranging from 39.0 to 62.9 g/100 g fatty acids.
The tested seed flours demonstrated significant TPC and free radical scavenging activities. Milk thistle seed flour had the
highest TPC value of 25.2 mg gallic acid equivalent per g flour (GAE mg/g) followed by that of parsley seed flour at 8.1 GAE
mg/g. Milk thistle seed-flour extract also had significantly higher antioxidant activities than all other extracts against
all tested radicals. The milk thistle seed-flour extract had an ORAC value of 1131 μmol trolox equivalents (TE) per g flour
(TE μmol/g), a HOSC value of 893 TE μmol/g, and an RDSC value of 61 TE μmol/g. Also, ORAC, HOSC, and TPC values were significantly
correlated (P < 0.01) under the experimental conditions. The cold-pressed milk thistle seed flour inhibited the proliferation of HT-29
cancer cells in a dose-dependent manner. Results from this study suggest that these cold-pressed seed flours may serve as
natural sources of antioxidants and may be used to improve human health. 相似文献
19.
Nitrogen (N) and phosphorus (P) co-doped anatase TiO2 nanosheets were realized by low-temperature self-doping N–TiO2 followed by high-temperature P doping with foreign precursor. It is found that P doping process can maintain good TiO2 nanosheets morphology with exposed {001} facets. Chemical state of dopants indicates that N and P atoms replace O on O sites in TiO2 lattice. Compared with pure TiO2 and N-doped TiO2, N–P co-doped TiO2 nanosheets exhibits stronger optical absorption and higher degradation rate of dye molecules in visible light regime. The enhanced photocatalytic properties are attributed to two factors. On one hand, N–P co-doping can effectively reduce band gap of TiO2 from 3.20 to 2.48 eV, leading to an enhancement of the absorption in visible light regime. On the other hand, the presence of exposed {001} facets of TiO2 nanosheets can induce the effective separation of photogenerated electrons and holes in reaction. 相似文献
20.
Despite structured enforcement of food hygiene requirements known to prevent foodborne disease outbreaks, catering businesses continue to be the most common setting for outbreaks in the United Kingdom. In a matched case control study of catering businesses, 148 businesses associated with outbreaks were compared with 148 control businesses. Hazard analysis critical control point systems and/or formal food hygiene training qualifications were not protective. Food hygiene inspection scores were not useful in predicting which catering businesses were associated with outbreaks. Businesses associated with outbreaks were more likely to be larger small and medium-sized enterprises (SMEs) or to serve Chinese cuisine and less likely to have the owner or manager working in the kitchen, but when size of the SME was taken into account these two differences were no longer significant. In larger businesses, case businesses were more likely to be hotels and were more commonly associated with viral foodborne outbreaks, but there was no explanation within the data for this association. 相似文献