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烹调油烟致大小鼠肺癌的实验研究 总被引:1,自引:0,他引:1
[目的]了解烹调油烟(cooking oil fumes,COF)的动物致癌性。[方法]采用动式染毒法给Balb/c小鼠(雌雄各半)吸入COF浓度为9.09、20.65、38.85mg/m^3,染毒1次/1~2d,30min/次,共150次,计8个月;SD大鼠(雌雄各半)吸入COF浓度为6、88、15.06、35.33mg/m^3,染毒1次/2d,30min/次,共191次,计12.5个月。分别制备COF慢性中毒动物模型;两实验均设空白对照组,吸入与实验组相同温度的清洁空气。[结果]COF诱发Balb/c小鼠实验组肺癌总发生率为18、95%(29/153),低、中、高浓度组肺癌发生率分别为15.09%、20、00%和22.00%,与对照组差异均有显著性。但低、中、高三组间差异无显著性(P〉0.05);COF诱发SD大鼠肺癌总发生率为9、10%(9/99),低、中、高浓度组肺癌发生率分别为6.45%、8.57%、12.12%,高浓度组肺癌发生率高于对照组(P〈0.05)。各性别组间肺癌发生率的差别无显著性(P〉0.05)。[结论]COF可以诱导Balb/c小鼠和SD大鼠肺癌,诱发的肺癌主要为肺腺癌(小鼠28/29,大鼠7/9),余为小细胞肺癌。 相似文献
3.
Sutureless bowel anastomosis using Nd:YAG laser 总被引:5,自引:0,他引:5
Small bowel anastomoses were performed without sutures by using the Nd:YAG laser to produce welded enterotomies. Optimal energy levels for contact and noncontact laser were determined. Anastomoses produced using five target energy levels between 100 and 500 J were examined. Short-term anastomotic strength of these enterotomies was measured 1 min after the welding. Bursting pressure of the laser welded enterotomies was compared to the bursting pressure of traditional two-layer, inverting, interrupted sutured bowel anastomoses. The overall mean bursting pressure of non-contact-welded enterotomies was 50.6 mmHg. Optimal laser settings determined in this initial phase were then used to produce anastomoses in rabbits which are recovered postoperatively for 1 or 2 weeks in order to examine long-term viability and integrity of the anastomoses. All chronic rabbit preparations recovered without complication. The mean bursting pressure was 200 mmHg, not significantly different from that of uncut bowel or two-layer sutured anastomosis. 相似文献
4.
烹调油烟对机体健康的危害 总被引:17,自引:0,他引:17
烹调油烟气含有200多种有害气体。实验研究和流行病学调查表明:油烟气可损伤肺部功能,引起机体免疫功能下降,并具有致突变性和致癌性,是肿瘤发生的可疑因素。 相似文献
5.
Progressive motor syndrome in a welder with pallidal T1 hyperintensity on MRI: A two-year follow-up.
Chronic exposure to manganese (Mn) fume during welding may lead to mainly extrapyramidal syndrome that is resistant to treatment. We present a 32-year-old patient who developed severe postural instability, Parkinsonism, dystonia, and pyramidal signs in the 10th year of welding. The neurological condition of the patient worsened markedly in the following 3 years, resulting in severe disability rendering him to be assisted in all his daily activities and he did not benefit from any dopaminergic agent. T1 sequences of the MRI of the brain showed pallidal hyperintensity symmetrically. Welders in our country often protect their eyes but ignore to use tools that protect them from inhalation of the fume. Since chronic Mn toxicity may cause serious disability and irreversible neurological disturbances, we strongly believe that it is necessary to inform welders and their employers about this potential hazard. 相似文献
6.
J. Angerer G. Lehnert 《International archives of occupational and environmental health》1990,61(8):7-10
Summary Stainless steel welders (n = 103) were examined. To estimate external exposure, personal air sampling was used. Internal exposure was quantified by
the determination of nickel levels in erythrocytes, plasma and urine. Men and women (n = 123) were examined for control purposes. In the plasma and erythrocytes of the controls the nickel concentration was below
the level of detection (< 1.81 μg/l). The element concentrations in urine were between < 0.1 and 13.3 μg/l. Of the controls
95% showed nickel levels in urine below 2.2 μg/l (reference value). The average concentration of nickel in the air was 93
± 81 μg/m3. The average concentration of nickel in the plasma samples was 4.9 ± 4.0 μg/l (95th percentile 12.8 μg/L). In erythrocytes
nickel could not be detected. The nickel concentrations in the urine of the welders were 18.5 ± 28.5 μg/l on average (95th
percentile 52.5 μg/l). Only a weak correlation between the nickel levels of plasma and urine could be detected (Curine = 2.07 + 8.45 Cplasma; r = 0.294; p < 0.01). Based on our results and on the reported literature a future limit value for the nickel concentration in urine should
lay between 30 and 50 μg/l. This value corresponds to an external exposure of 500 μg nickel per cubic metre. 相似文献
7.
目的观察以宗四维牵引和熏腰蒸气疗法治疗腰椎间盘突出症的临床疗效。方法应用仰卧纵轴骨盆牵引,俯卧骨盆牵引同时外展患肢牵引,仰卧屈曲双下肢悬吊牵引,俯卧过伸双下肢悬吊牵引,根据患者椎曲的改变类型辩证施治;牵引后进行熏腰蒸气治疗。结果腰椎间盘突出症治疗有效率为93%,无效率7%。 相似文献
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10.
烹调油烟致肺组织P^53基因异常表达的实验研究 总被引:2,自引:0,他引:2
目的 检测吸入烹调油烟 (COF)的大鼠肺组织中P53 蛋白含量 ,以测试烹调油烟的毒性作用。方法 亚急性吸入浓度为 (43± 4 )mg m3 的烹调油烟作实验组 ,吸入加热空气 (2 4~ 2 8℃ )为阴性对照组 ,B(a)P气注法染毒 [12mg (kg·次 ) ,5天 1次 ]动物作阳性组。常规病理组织取材、切片 ,免疫组化法 (S -P试剂盒 )检测P53 蛋白水平。结果 阴性对照组P53 蛋白表达阴性 ;COF组有P53 蛋白表达 ,染毒时间越长 ,P53 蛋白阳性数越多 ,以细胞增生、异型增生病变组织中P53 表达阳性数为多 ;B(a)P组有P53 蛋白表达 ,但看不出时相规律。结论 烹调油烟致P53 蛋白表达增高 相似文献