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91.
Bulletin of Environmental Contamination and Toxicology - The toxicity of high-chlorinated polychlorinated biphenyls (PCBs) can be efficiently reduced through anaerobic dechlorination. However, this...  相似文献   
92.

The relationship between the migration process and speciation distribution of Cr is important for the risk assessment in the underground environment. In this work, soil columns were collected from the chromate production site, with a 40-year operation, in the groundwater depression cone area of North China plain. The relationship between chromium pollution features and the geochemical properties of soil was established, and the migration risk of Cr(VI) was assessed based on the Nemerow composite index and Hydrus-1D model. The maximum total Cr concentration in the chromium slag dumping site reached 907 mg/kg, and that in the chromate production workshop was more than 200 mg/kg across the depth. The migration of Cr might be accelerated in the soil with abundant Mn (236–1461 mg/kg) but scarce organic matters (<?0.45%). The Hydrus simulation indicated that Cr(VI) would reach a cumulative flux of 300–729 mg/cm2 after 50 years.

  相似文献   
93.

Air samples were collected around industrial parks in Jiangsu, China, to allow the concentrations, profiles, and risk assessment of polybrominated dibenzo-p-dioxins and dibenzofurans (PBDD/Fs), polychlorinated naphthalenes (PCNs), and metals to be investigated. The concentrations of ΣPBDD/Fs and ΣPCNs were 1324.26–2080.98 fg/m3 (11.35–42.57 fg I-TEQ/m3) and 10,404.9–29,322.9 fg/m3 (1.32–7.19 fg I-TEQ/ m3), respectively. The highest concentration of ΣPBDD/Fs and ΣPCNs were observed at site C. PBDD/Fs were mainly dominated by PBDFs. The main contributor to the ΣPBDD/Fs in all samples was 1,2,3,4,6,7,8-HpBDF, which accounted for 25.75%–39.4%. For PCNs, the predominating homologues were tetra-, tri- and penta-CNs, which contributed 30.7%–43.3%, 24.7%–31.0%, and 10.6%–21.6%, respectively. As for metals, the pollution of As, Mn, Cr, and Ni in most samples exceeded National Ambient Air Quality Standards of China. Assessing the risk of inhalation exposure showed that there were potential carcinogenic risks to local residents.

  相似文献   
94.
Bulletin of Environmental Contamination and Toxicology - Phthalates are one of ubiquitous contaminants in the indoor environment. In this study, we analyzed concentrations and profiles of 9...  相似文献   
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97.
应用核酸分子杂交技术检测心肌炎组织中的肠道病毒RNA   总被引:4,自引:0,他引:4  
沈茜  汪美先 《中华病理学杂志》1994,23(2):79-81,T014
用生物素标记pCBIII/35和pCBIII/51肠道病毒属特异性探针,对45心肌炎和心肮病尸检或心肌活检心脏组织进行原位杂交,结果显示:12例(26.6%)存在肠道病毒RNA。柯萨基B3病毒型特异性探针pCBIII/29进一步杂交表明,12例经证实存在肠道病毒RNA的心肌组织中5例(41.7%)出现阳性杂交信号。阳性杂信号主要位于单个或多个心肌细胞的胞浆和心肌的间质组织,偶见竽心肌小血管内皮细胞  相似文献   
98.
目的 探讨降纤酶对青年人短暂性脑缺血(TIA)发作的治疗效果。方法 将72例患者随机分为两组。治疗组37例,给予降纤酶静滴至TIA发作终止或治疗达1周;对照组35例,给予阿司匹林、尼莫地平、低分子右旋糖酐、脉络宁治疗2周。两组于治疗前、后分别采静脉血检测血浆纤维蛋白原、红细胞压积、全血粘度和血浆粘度的变化。结果 总有效率治疗组为91.66%,对照组为77.14%,2组间有显著性差异(P〈0.01)  相似文献   
99.
采用抽样研究方法,对438名不同专业、不同层次的大学生进行了医德认知调查,以了解大学生对医德基本知识掌握的情况,结果表明,大学生对开设医学伦理学课必要性认识均率为62.9%,课外经常阅读医德书籍均率为22.75%,对中外基德发展史各朝代典型的人物及代表作了解的均率为31.1%,文中对调查结果进行了分析。  相似文献   
100.
Intermittent administration of PTH has been found to be an effective anabolic agent in cancellous bone. We have reported previously that combined treatment with PTH and estrogen in estrogen-deficient rats was beneficial in correcting established osteopenia. To determine if the beneficial effects of PTH therapy can be preserved by estrogen alone and whether PTH therapy can be effective in treating osteopenic subjects stabilized with estrogen, we have undertaken a "crossover" study in the rat model of estrogen-deficiency induced osteopenia. Six-month-old female rats were ovariectomized and after 5 wk treated for 8 wk with vehicle, 30 micrograms/kg per day of rPTH(1-34) plus 15 micrograms/kg per day of 17 beta-estradiol or 17 beta-estradiol alone. One group from each treatment regimen was then sacrificed and for an additional 8 weeks the remaining rats were (a) maintained on their previous treatment; (b) "crossed over" to their reciprocal treatment; or (c) administered vehicle only. At the end of this second 8-wk treatment period all rats were sacrificed. Bone mineral density of the distal femur, histomorphometric measurements of the proximal tibia and mechanical testing of the distal femur and selected vertebral bodies were performed. Our results demonstrated that (a) the gains in bone mass, trabecular connectivity and mechanical strength induced by PTH can be maintained by estrogen alone, but are reversed when both agents are withdrawn; and (b) rats with established osteopenia, maintained on estrogen treatment alone, can derive the full beneficial effects from the addition of PTH to the treatment at a later date. These data indicate that combined and/or sequential use of antiresorptive and anabolic agents may be a promising approach to the treatment of osteoporosis.  相似文献   
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