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31.
This study examined 117 patients with mild cervical atypia or atypical squamous cells of uncertain significance; it was found that 25% had histologically proven CIN lesions by colposcopically-directed punch biopsy or cone biopsy. 18% were found to have at least CIN 2 lesions and there was 1 case of invasive cancer. These data strongly support the recommendation of early colposcopic referral in patients with mild cervical atypia. 相似文献
32.
M Casu G Saba A Lai M Luhmer A Kirsch-De Mesmaeker C Moucheron J Reisse 《Canadian Metallurgical Quarterly》1996,59(1-2):133-138
The possibility of using sodium-23 spin-lattice relaxation rate measurements to probe the interaction modes of Ru11 polyazaaaromatic complexes with DNA is investigated. The following complexes are considered: Ru(phen)3(2+) (phen = 1.10-phenanthroline), Ru(phen)2HAT2+ (HAT = 1,4,5,8,9,12-hexaazatriphenylene), and Ru(diMeTAP)3(2+) (diMeTAP = 2,7-dimethyl-1,4,5,8-tetraazaphenanthrene). The addition of Ru(diMeTAP)3(2+) to a solution of NaDNA leads to a decrease in the sodium-23 spin-lattice relaxation rate (R1) similar to the effect observed upon addition of Mg2+. This indicates that Ru(diMeTAP)3(2+) interacts like Mg2+ with DNA and consequently that the electrostatic interaction dominates the association with DNA, Ru(phen)3(2+) and Ru(phen)2HAT2+ diminish R1 more efficiently than Mg2+, in a manner similar to ethidium bromide, which is known for its intercalation properties. Thus interactions other than electrostatic occur between these two complexes and DNA. These results are in agreement with data obtained from other techniques, according to which Ru(phen)3(2+) and Ru(phen)2HAT2+ are located partially inside the DNA double helix, in contrast to Ru(diMeTAP)3(2+) which remains in the ionic atmosphere around the phosphate backbone. 相似文献
33.
This paper investigates the deformation mechanism of a single-walled carbon nanotube in pure bending. The molecular dynamics
analysis and continuum mechanics characterisation were used together to achieve a deeper understanding. It was found that
at a bending angle of 24° the nanotube buckles locally, forming a kink in the middle of the nanotube. As the bending angle
increases, the kink progresses along the nanotube and varies its shape in both longitudinal and circumferential directions.
The kink formation can be considered as the result of rotations of planes/surfaces about the moving and stationary hinge lines.
It was also found that the kink deformation influences the load bearing capacity of the nanotube. 相似文献
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Mehvish Iram Umar Asghar Zile Huma Saba Jamil Muhammad Nadeem 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(3):364-372
In this study, sugarcane bagasse (2 mm) was pretreated with 2.5% NaOH followed by steaming at 121°C for various time periods. Maximum cellulose content of 81% and delignification of 68.5% were achieved by soaking bagasse in 2.5% NaOH with a residence time of 1 h at room temperature followed by steaming at 121°C for 30 min residence time. The pretreated substrate was analyzed by SEM and FTIR to study the structural modification and functional group of the untreated and pretreated substrates. The pretreated substrate was saccharified by commercial cellulase enzyme depicting 106 µm mesh size of substrate yields maximum saccharification rate. The saccharified material was fermented by Saccharomyces cerevisiae and Pichia stipitis in mono- and co-culture modes. Maximum product yield (Yp/s) was observed by monoculture using Saccharomyces cerevisiae after 96 h of fermentation period. 相似文献
39.
Hosain Darvishi Nasser Behroozi-Khazaei Mahmoud Koushesh Saba Zakaria Alimohammadi Himan Nourbakhsh 《International Journal of Food Science & Technology》2021,56(9):4789-4798
The antioxidant, phenol, ascorbic acid, electrode corrosion and engineering factors of concentration process of kiwifruit juice by ohmic heating-vacuum conditions (OHVC) were evaluated and compared with ohmic heating under atmospheric conditions (OHAC). Results showed that the total phenol content was decreased with an increasing voltage gradient for both heating modes. The OHVC can better save the antioxidant capacity and ascorbic acid of concentrated samples than the OHAC. The processing time of OHVC was significantly higher than the OHAC at the same voltage gradient (P < 0.05). The electrode corrosion rate at the vacuum mode was 7- to 40-fold higher than the atmospheric mode. The energy efficiency at OHAC was lower than the OHVC. The energy consumption was found in the range of 3.37 to 3.75 MJ kg−1 water for OHAC and 4.08 to 11.09 MJ kg−1 water for OHVC. The electrical conductivity under the vacuum mode was lower than the atmospheric mode. 相似文献
40.
Changes in olive oil volatile organic compounds induced by water status and light environment in canopies of Olea europaea L. trees 下载免费PDF全文