A series of bioassays such as sister chromatid exchange frequencies ( SCE.), chromosomal aberration ( CA ), micronuclel rate (MN) and cell-cycle delay have been used to detecting the genotoxic effect of cigarette smok...A series of bioassays such as sister chromatid exchange frequencies ( SCE.), chromosomal aberration ( CA ), micronuclel rate (MN) and cell-cycle delay have been used to detecting the genotoxic effect of cigarette smoke condensate (CSC) on human diploid cell 2BS strain. The results suggested that a higher SCE, ( 17. 0/ cell) was observed In 2BS cells treated with CSC at 100 μg/ml, as compared with 6. 9/cell of the background (P<0. 001). CA rate was significantly increased from 4% to 36% In cells treated with 10 μg/ml CSC (P< 0.001). MN rate varied from 9 -26‰ In cells treated with CSC compared to that of control (6‰). Meanwhile, the cell-cycle of cells was markedly delayed by CSC. The survival rate of 2BS cells declined to 59. 6% for treatment with CSC at 200 μg/ ml. There was a dose-effect response In SCE., CA, MN rate. We proposed that active oxygen might responsible for genotoxiclty of CSC on cells.展开更多
For studying the influence of smoking on temporary threshold shift (TTS), six normal subjects (3 smokers and 3 nonsmokers) were selected for carrying out this work. Nonsmokers were exposed separately for 7 min to 95 ...For studying the influence of smoking on temporary threshold shift (TTS), six normal subjects (3 smokers and 3 nonsmokers) were selected for carrying out this work. Nonsmokers were exposed separately for 7 min to 95 dB SPL in 1/3-octave band filtered noise centred at 2 kHz. Pre and post exposure thresholds (leftear) were recorded in a sound-proof booth using Bruel & Kjaer (B & K) Audiometer type 1800. For smokers, each one smoked a cigarette during the five minutes following the pre-exposure threshold measurement. All the assessments were conducted at a temperature between 22-25℃. The results indicated that smokers evidenced less TTS than did nonsmokers in the frequency range from 1 kHz to 5 kHz. At 6 kHz smokers evidenced nearly higher value. Maximum TTS was attained at frequency that was about 1/2-octave higher than that of the exposed noise. Comparison between recovery curves for smokers and nonsmokers was also made.展开更多
文摘A series of bioassays such as sister chromatid exchange frequencies ( SCE.), chromosomal aberration ( CA ), micronuclel rate (MN) and cell-cycle delay have been used to detecting the genotoxic effect of cigarette smoke condensate (CSC) on human diploid cell 2BS strain. The results suggested that a higher SCE, ( 17. 0/ cell) was observed In 2BS cells treated with CSC at 100 μg/ml, as compared with 6. 9/cell of the background (P<0. 001). CA rate was significantly increased from 4% to 36% In cells treated with 10 μg/ml CSC (P< 0.001). MN rate varied from 9 -26‰ In cells treated with CSC compared to that of control (6‰). Meanwhile, the cell-cycle of cells was markedly delayed by CSC. The survival rate of 2BS cells declined to 59. 6% for treatment with CSC at 200 μg/ ml. There was a dose-effect response In SCE., CA, MN rate. We proposed that active oxygen might responsible for genotoxiclty of CSC on cells.
文摘For studying the influence of smoking on temporary threshold shift (TTS), six normal subjects (3 smokers and 3 nonsmokers) were selected for carrying out this work. Nonsmokers were exposed separately for 7 min to 95 dB SPL in 1/3-octave band filtered noise centred at 2 kHz. Pre and post exposure thresholds (leftear) were recorded in a sound-proof booth using Bruel & Kjaer (B & K) Audiometer type 1800. For smokers, each one smoked a cigarette during the five minutes following the pre-exposure threshold measurement. All the assessments were conducted at a temperature between 22-25℃. The results indicated that smokers evidenced less TTS than did nonsmokers in the frequency range from 1 kHz to 5 kHz. At 6 kHz smokers evidenced nearly higher value. Maximum TTS was attained at frequency that was about 1/2-octave higher than that of the exposed noise. Comparison between recovery curves for smokers and nonsmokers was also made.
