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111.
江西某地“癌症高发区”的报道引起了社会的广泛关注。通过对该地土壤、水体、降尘地质环境调查评价,认为调查区土壤环境质量较好,为清洁区,仅镍元素达轻度污染级。地下水质量为较差级,外围为优良级。饮用水源地水质综合评价为较差级,有机氯农药检出2项,多环芳烃检出10项,萘达到轻度污染级。区域地质、水文地质背景不具特殊性,土壤、水体地质环境与周边南昌地区无明显异常,是否与癌症发病有直接的关系,尚需作进一步的调查研究工作。降尘污染较为严重,污染因子主要为镉,应引起重视。 相似文献
112.
Dr R. J. Morrow M. J. Whittle Margaret B. McNay P. A. M. Raine A. A. M. Gibson Jenny Crossley 《黑龙江环境通报》1993,13(2):111-115
An attempt was made to identify all the cases of abdominal wall defects occurring in the West of Scotland over a 7-year period to determine the current incidence, prenatal diagnosis, management, and prognosis for fetuses and neonates with abdominal wall defects. Cases were identified because they presented either for prenatal diagnosis, or to the Department of Pathology following termination or spontaneous pregnancy loss, or as neonates to the Neonatal Surgical Department. The incidence of abdominal wall defects was found to be 1 in 2500 births. Exomphalos was diagnosed before birth in 66 per cent of cases, and in 30 per cent of cases it was associated with another major abnormality. There was a 20 per cent intact survival in the cases diagnosed prenatally who had no fetal anomaly and who opted to continue with the pregnancy. Gastroschisis was diagnosed before delivery in 70 per cent of cases, and in the group who continued with the pregnancy there was an intact survival of 77 per cent. Body stalk anomalies were all diagnosed prenatally and terminated. Maternal serum alpha-fetoprotein was elevated in 89 per cent of the cases with exomphalos and in 100 per cent of the cases with gastroschisis and body stalk anomalies in which it was tested. 相似文献
113.
Eric Jauniaux Sanjay Vyas Caroline Finlayson Gonzalo Moscoso Marie Driver Stuart Campbell 《黑龙江环境通报》1990,10(2):127-132
Ultrasonographic features of a fetus at 18 weeks of gestation suggesting a body stalk anomaly are presented. These included a large abdominal anterior wall defect in apparent continuity with the placenta, severe kyphoscoliosis of the lower spine, the absence of one kidney, and a very short umbilical cord with only one umbilical artery. The amniotic fluid was reduced and the fetus was almost immobile at short-interval ultrasound examinations. The pregnancy was terminated and autopsy of the fetus showed abnormalities compatible with maldevelopment of both cephalic and caudal embryonic folds. 相似文献
114.
Dr. D. Arduini G. Rizzo C. Giorlandino H. Valensise S. Dell'Acqua C. Romanini 《黑龙江环境通报》1986,6(2):117-124
In order to evaluate the development of fetal behavioural states a longitudinal study was performed on 35 healthy fetuses during the last trimester of pregnancy. Fetal heart rate (FHR), gross fetal body movements (FM), fetal eye movements (FEM), fetal breathing movements (FBM) and micturition were simultaneously studied at two-week intervals from 28 weeks gestation onwards. Well-defined fetal behavioural states were observed only after 36 weeks gestation. Between 28 and 36 weeks the quiet-activity cycle of FHR was always detected and some fetal biophysical activites seemed to become related around this cycle. 相似文献
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用专用设备将待卷圆钢板两端先压成所需圆弧后再卷,提高焊缝质量,减少了加工工时。根据泰州第二纺织机械厂的生产需要,为其设计的360t压头机,成功地解决了该厂纺机产品中滚筒卷圆的生产问题。介绍了该机的工作原理,焊接式床身的结构以及液压传动系统的特点。 相似文献
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采用合理的模具结构、选择合适的模具材料、采用适宜的热处理工艺和表面强化工艺以及提高模具的加工质量等都可以显著提高温冲压模具的使用寿命。分析了超高强度钢制深盲孔壳体温冲压成形时,模具的工作条件及其失效形式,提出了能有效提高该壳体温冲压模具寿命的具体措施。 相似文献
120.
重金属对食品的污染及其危害 总被引:6,自引:0,他引:6
铅、砷、汞、镉、锡等有毒重金属通过各种途径污染食品,沿食物链进入人体后,给人体健康带来严重危害.本文综述了几种重金属对食品的污染及其来源,对人体的危害及其预防,以便提高人们的食品安全意识,加强环境保护,维护人体健康. 相似文献