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971.
Tsukahara K Takema Y Fujimura T Moriwaki S Kitahara T Imokawa G 《International journal of cosmetic science》2000,22(4):247-258
The usefulness of the photo standard for evaluating skin sagging in the face, especially in the cheeks, was evaluated. A six-stage photo standard was prepared using photos of women aged 17-83-years-old at three magnification rates (136-188 women in each group). Based on this photo standard, scoring was performed using a six-grade scoring system by two specialists to obtain the consensus score. Scoring was also performed in parallel by five general observers. The degree of agreement between the two scores was evaluated by calculating the Kappa value. In each group, the Kappa value was 0.452-0.563, indicating moderate agreement. Thus, the photo standard may be useful for evaluating sagging. Based on the photo standard, a score of 2, at which sagging becomes detectable appeared at the age of 40 years. In parallel, 3D analysis of replicas around the cheek was performed to morphologically analyse age-related changes in sagging. When the depth parameter was compared between the nasolabial groove and the mouth corners, a higher value was observed in the nasolabial groove until the age of 40 years, but higher values were seen in the mouth corners thereafter. This may have been because sagging in the cheeks descends to the area around the mouth, resulting in reversion in the sWv value. These findings indicated that sagging in the cheeks becomes morphologically distinct in women in their forties. 相似文献
972.
Microbial succession during ripening of Naples-type salami, a southern Italian fermented sausage 总被引:6,自引:0,他引:6
Studies were carried out on the microbiological and physico-chemical changes which occurred during the ripening of five batches of Naples-type salami, manufactured without starter cultures. Salami were sampled internally and externally, and the following microbial groups were studied: lactic acid bacteria, Micrococcaceae and yeasts. The results obtained indicated that lactobacilli constituted the predominant flora, both on the surface and in the interior of the pieces throughout the ripening period. Micrococcaceae and yeasts were also found in considerable number in both locations. Characterisation of 191 lactic isolates indicated that the salami microflora was dominated by homofermentative lactobacilli; approximately 63% of them could be identified as Lactobacillus sake; 40% showing the traits of a racemase negative variant of this species, once referred to Lactobacillus bavaricus. Yeast population mainly comprised Debaryomyces strains. All the colonies grown on mannitol salt and Kranep agar were catalase-positive cocci; novobiocin-resistant staphylococci were the only Micrococcaceae found. The API Staph identification system did not prove to be reliable: 82% of the isolates remained unidentified. To achieve improved characterisation, cluster analysis was subsequently performed on this group, corroborating the existence of a fairly homogeneous group representing an intermediate variety between Staphylococcus xylosus and Staphylococcus saprophyticus that was isolated during the whole ripening process. 相似文献
973.
Multidrug-resistant Salmonella Typhimurium DT104 in poultry 总被引:2,自引:0,他引:2
Rajashekara G Haverly E Halvorson DA Ferris KE Lauer DC Nagaraja KV 《Journal of food protection》2000,63(2):155-161
Salmonella Typhimurium isolates from feed ingredients or poultry sources isolated during 1995 to 1997 from different geographical locations within Minnesota were examined for the presence of Salmonella Typhimurium definitive type 104 (DT104). Antibiotic susceptibility studies indicated that 15 of 50 isolates of Salmonella Typhimurium had an antibiotic resistance pattern (ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline) that is usually observed with multidrug-resistant Salmonella Typhimurium DT104. Of the 15 isolates showing the antibiotic resistance pattern, 8 isolates were phage type 104, 3 isolates were typed as phage type 104 complex, and the remaining 4 isolates belonged to phage types 193, 81, and 126. DT104 was recovered from both feed ingredients and poultry samples. Of the seven feed ingredient-associated Salmonella Typhimurium isolates, four were DT104, whereas only 7 of 43 poultry-associated Salmonella Typhimurium isolates were DT104. A repetitive sequence-based polymerase chain reaction (rep-PCR) of 50 isolates of Salmonella Typhimurium representing 13 phage types identified seven distinct fingerprint profiles. No correlation between phage type and rep-PCR type was noticed. Eleven Salmonella Typhimurium isolates belonging to DT104 and its complex were grouped into two closely related rep-PCR types. 相似文献
974.
Ikeda K Pant B Mishiro A Ozawa K Masujima T Sugiyama M 《Journal of Bioscience and Bioengineering》2000,90(5):574-576
Mitotic index (MI), defined as the ratio (%) of the mitotic-phase-arrested cell number to the total cell number, is higher in the presence of colcemid than in its absence. MI is reduced by anti-tumor agents used in conjunction with colcemid. The ratio of MI, which is defined by the dose of colcemid to that of the supplement with etoposide as an anti-tumor agent and is designated MIR, was 10% at an exposure of 2 h, suggesting that etoposide blocks the cell cycle before 2 h of the mitotic phase. Thus, we established a convenient method to identify a target point in the cell cycle for anti-tumor agents using colcemid. RBL-2H3, a mammalian cell line, exhibited a large number of 2-fold swollen nuclear envelopes after exposure to etoposide. The G2-index, which is the ratio of the number of swollen nuclei to the total number of nuclei, was higher when the cells were incubated with etoposide than without it. In this study, we suggest that the measurement of the G2-index contributes to the screening of putative anti-tumor agents. 相似文献
975.
The use of lipid-containing semipermeable membrane devices (SPMDs) is becoming commonplace, but the potential effects of environmental variables affecting the accumulation of contaminants into SPMDs had not been characterized sufficiently, yet. To characterize the effect of hydrodynamic conditions on the contaminant uptake kinetics, accumulation of pentachlorobenzene, hexachlorobenzene, and hexachlorocyclohexane isomers from water into SPMD was studied at various water flow rates. The accumulation kinetics of hydrophobic compounds (log Kow > 4) are governed by the aqueous boundary layer in linear flow velocity range from 0.06 to 0.28 cm s(-1) and sensitive to slight changes in flow rate. The effect of flow velocity on the exchange kinetics increases with increasing hydrophobicity. Under faster, but still laminar flow conditions (0.28-1.14 cm s(-1)), the sensitivity to changes in flow decreases to a nonsignificant level for the substances under consideration. The results of this study confirm that the use of the laboratory-derived calibration data for estimation of analyte concentrations in the ambient environment is limited unless flow-sensitive performance reference compounds are used. 相似文献
976.
奥地利SML公司的纺丝生产线可以生产各种各样的长丝。在巴黎ITMA’99上,SML公司展出了第一台用复丝来生产BCF丝的设备-Austrofil,这套设备会给生产商带来极大的便利。 相似文献
977.
Janvikul W Uppanan P Thavornyutikarn B Prateepasen R Swasdison S 《Journal of materials science. Materials in medicine》2007,18(5):943-949
The interaction between L929 cells and carboxymethylchitosan (CM-chitosan)-based hydrogels, hydrogels from pure CM-chitosan
and its blends, was examined in this study. Cytotoxicity of all materials was also assessed. The cellular morphology and behavior
on the surfaces of the hydrogels were observed by scanning electron microscopy (SEM). The effects of various parameters, e.g.,
type and content of blended polymers, surface structure of hydrogels, and steaming condition used for the preparation of the
hydrogels, on the cell-material response were investigated. The results of the cytotoxicity test revealed that all hydrogels
were non-cytotoxic. The SEM micrographs demonstrated that the cells proliferated and spread onto a porous CM-chitosan sample.
Better cell spreading was found on a flat surface of a CM-chitosan film. Rounded cells were observed when poly(vinyl alcohol)
(PVA) was incorporated into CM-chitosan. Fewer cells were found when the content of PVA increased. Spherical clusters of the
aggregated cells existed in the blends with ultra high viscosity carboxymethylcellulose (CM-cellulose). In contrast, with
the use of low viscosity CM-cellulose, the cells appeared more spreading. The attached cells on the CM-chitosan film steamed
at the highest temperature and longest period appeared to spread the most among all tested steaming conditions. 相似文献
978.
The cause and control of foaming and bulking in triple oxidation ditch at a wastewater treatment plant (WWTP) were investigated. The results showed that the foaming and bulking was mainly caused by the excessive propagation of Microthrix parvicella, and mostly occurred in the cold winter and spring. Batch and continuous flow experiments indicated that biological techniques such as reducing sludge retention time (SRT) and increasing F/M ratio, chemical methods such as addition of chlorine (NaOCl), quaternary ammonium salt (QAS), or cationic polyacrylamide flocculants (PAM), polyaluminum salt (PAC) could decrease Sludge Volume Index (SVI) and control foaming and bulking at different levels. In practical application, the shorter SRT was effective to control foaming and bulking in initial stage, although it took longer time. Addition of 10gClkgMLSSd(-1) could gradually change the activated sludge with serious foaming and bulking to normal state within a week. Pre-alert control strategies should be established for the control of filamentous foaming and bulking. 相似文献
979.
Mahalakshmi M Arabindoo B Palanichamy M Murugesan V 《Journal of hazardous materials》2007,143(1-2):240-245
The photocatalytic degradation of carbofuran (2,3-dihydro-2,2-dimethylbenzofuran-7-yl methylcarbamate) was investigated in an aqueous solution using Degussa P-25 TiO2 and ZnO as photocatalysts. The progress of degradation was monitored using TOC analyzer, HPLC, GC-MS and UV-vis spectrophotometer. The effects of various experimental parameters such as initial concentration of carbofuran, pH of the solution, catalyst loading and light intensity were systematically studied in order to achieve maximum degradation efficiency. The complete mineralization of carbofuran was confirmed by TOC analyzer. The degradation with ZnO showed less efficiency than TiO2. The formation of NO(3)(-) was identified and quantified using HPLC. In addition, four different intermediates formed during the degradation process were also identified and characterized by GC-MS. The mineralization rate was compared with lamps of wavelength 254 and 365 nm under similar conditions. The rate with 254 nm was observed to be very close to that of 365 nm. 相似文献
980.
The purpose was to estimate the radiation dose to the thyroid from total cranial irradiation with parallel opposed lateral fields of 1.25 MeV gamma rays of (60)Co, to represent the current treatment modality, and with 6 MV photon beams derived from a linear accelerator. The mean thyroid doses were measured using thermoluminescence dosemeters in the Rando phantom with two cranial irradiation set-ups: (1) the lateral beams were angled by rotating the collimator to avoid irradiation of the lens and healthy tissues and (2) the lateral beams were not angled, and shielding blocks were used to protect the lens and healthy tissues. For a cranial dose of 18 Gy, thyroid doses for child patients for (60)Co with the open and blocked fields were 0.27 and 0.32 Gy, respectively. With 6 MV, the thyroid dose was less than the doses for (60)Co open and blocked cranial fields by 17 and 10%, respectively. Unblocked cranial fields and a high-energy photon beam should be preferred for cranial irradiation of children. 相似文献