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排序方式: 共有4434条查询结果,搜索用时 15 毫秒
261.
目的探讨人细小病毒B19(HPVB19)感染与早期自然流产的关系。方法用酶联免疫吸附试验(ELISA)法检测52例早期自然流产患者(研究组)和45例无异常人工流产孕妇(对照组)血清中HPVB19-IgM和IgG。结果研究组血中B19V-IgM阳性率为23.08%,而对照组阳性率为6.67%,2组间具有显著性差异(P<0.05);研究组近期HPVB19感染的概率是对照组的4.20倍(95%CI 1.10~15.99)。研究组B19V-IgG阳性率为32.69%,对照组为28.89%,2组差异无统计学意义(P>0.05)。结论 HPVB19感染可能是导致早期自然流产的原因之一。 相似文献
262.
大学校园规划应由对“物”转而对“人”,“以人为本——表现和展示校园文化和生活”应成为校园规划的出发点和目标。该文以西南科技大学新校区为例,从设计构思、规划结构布局、多层次交流空间,以及校园环境等方面对高校校园规划进行了探讨。总结出围合空间具有较强的亲和力和凝聚力,流动的水体和山坡的原生树林,规划设计较好的利用地形地貌、自然环境,创造出校园的人文环境。 相似文献
263.
264.
PCBs and OCPs in human milk and selected foods from Luqiao and Pingqiao in Zhejiang, China 总被引:1,自引:0,他引:1
This study was conducted to measure the levels of 23 PCB congeners and 6 organochlorine pesticides (OCPs) in human milk and three food types collected from Luqiao and Pingqiao in Zhejiang Province, China. An effort was also made to explore the potential health risk for the mothers and breast-fed infants living in these two localities. Luqiao was selected as the sampling site because it is the largest place for the disassembly of obsolete transformers and electrical waste in China. Pingqiao, located 100 km NW of Luqiao, is not known to be a place for any electronic or electrical waste and hence was chosen as the control site. Both localities are important agricultural places in the province. The organochlorines were measured in the samples using the GC-muECD technique. Micro-EROD bioassay method was also used as a complement of the chemical analysis to estimate the TEQ levels of dioxin-like PCBs in human milk. The data showed that the human milk, rice, hen egg, and fish samples from Luqiao were more heavily contaminated with PCBs than those from Pingqiao, suggesting that the mothers and their breast-fed infants in Luqiao tended to receive greater exposure to PCBs than those living in Pingqiao. The OCP levels in the two localities were found comparable, suggesting that the major source of contamination with these pesticides was from their agricultural uses. Significant correlation (R2 = 0.87, P<0.001) of PCB TEQs was found between the bioassay and chemical analysis method, suggesting that micro-EROD is an effective method for comprehensive determination of TEQ levels in human milk. Comparison with literature data showed that the PCB levels in milk samples from Luqiao were significantly higher than those from localities in other Chinese provinces and comparable to those in developed or industrialized countries. 相似文献
265.
Zhang Tianyu YangYanhong 《建筑师》2008,(1)
建筑的本体应是人化的本体,而研究人化的本体要从构成人的基本要素——身体开始研究起。人类在建筑深层心理结构时,在形成建筑形态时,身体起到了重要作用;同时,"身体安全图式"作为人的心理结构,是人感知外界环境的标尺,人的生存空间只有与这个图式相吻合,人在其中才会有心理上的安全感与舒适感;而身体对外部世界的感知和理解又是通过知觉实现这个目的。因而,人性化的建筑应成为真正关乎人的身体和知觉的创造。 相似文献
266.
An evaluation of resident exposure to respirable particulate matter and health economic loss in Beijing during Beijing 2008 Olympic Games 总被引:1,自引:0,他引:1
Previous epidemiological studies showed that air pollutants, especially respirable particulate matter, including PM10, could impose harmful effects on human health. The assessment of the effects of PM10 on mortality and morbidity makes an important basis for enhancing pollution control efforts, and for protecting public health. In this study, we measured the levels of Beijing residents' exposure to PM10 during three different time periods around the Beijing Olympic Games held in 2008, and calculated the economic cost associated with human health. A comparative analysis of human exposure to PM10 and associated health economics was also made to see the difference between 2005 and 2008. GIS technology was employed to interpolate the distribution of population and PM10 data collected by 27 stations at a scale of 1 km × 1 km. Study results show that Beijing's population is distributed in a highly inhomogeneous manner, with the majority of people dwelling in the city proper. During the Olympic Games, population-weighted PM10 exposure came down by 46% and 19% respectively, compared with the pre-OG and the post-OG periods. Consequently, the economic cost associated with human health during the Games came down by 38% and 16% respectively, compared with the pre-OG and the post-OG periods. Comparative analysis shows that during the Olympic Games, both PM10 and the economic cost associated with health as a proportion of GDP sat at the bottom of the 4-year statistics, indicating that in addition to favorable weather conditions, enhanced traffic and emission control policies and measures have produced a noticeable effect on PM10 reduction. 相似文献
267.
借"名画"之余晖点江山之异彩--济南"鹊华历史文化公园"刍议 总被引:2,自引:0,他引:2
快速推进的城市化正在给中国城乡生态环境和文化环境带来极大的影响,以济南历史上的名胜地区鹊华为例,建议规划建设济南“鹊华历史文化公园“,希望在城乡统筹、可持续发展思想指导下,探索具有保护自然、改善生态、发扬文化、重振河山等多方面效益的人居环境建设新模式. 相似文献
268.
Incidence of adenoviruses in raw and treated water 总被引:6,自引:0,他引:6
Adenoviruses are of major public health importance and are associated with a variety of clinical manifestations, i.e. gastroenteritis, eye infections and respiratory infections. The importance of water in the epidemiology of adenoviruses and the potential health risks constituted by adenoviruses in water sources and supplies are widely recognised. This study was conducted to assess the incidence of human adenoviruses in raw and treated water systems. Various raw and treated water were routinely monitored for the presence of adenoviruses, over a 1-year period (July 2000-June 2001). The supplies were derived from acceptable quality surface water sources using treatment processes, which conform to international standards for the production of safe drinking water. Adenoviruses were detected by firstly amplifying the viruses in cell cultures and then amplifying the extracted nucleic acids of these viruses using molecular techniques (nested PCR). The results indicated human adenoviruses present in 13 (12.75%) of the raw and 9 (4.41%) of the treated water samples tested. The combination of cell culture and nested PCR has proved to be a quick and reliable method for the detection of adenoviruses in water environments. 相似文献
269.
A variety of human land uses involve the release of toxins into the environment. Wildlife live alongside humans across this array of land uses and thus, are exposed to varying chemical milieus. Kidneys are the principle excretory organs for vertebrates and excessive or chronic exposure to exogenous toxins can lead to renal pathology and renal failure. Although studies have linked chemical exposure to specific renal diseases across diverse taxa, none compare renal lesions occurring in wildlife living in different types of human-modified landscapes. We identify lesions characteristic of renal stress, including toxin exposure, in 82 giant toad (Bufo marinus) males living in habitats ranging from suburban to agricultural. In a previous study [McCoy K.A., Bortnick L.J., Campbell C.M., Hamlin H.J., Guillette L.J., Jr., St. Mary C.M. Agriculture Alters Gonadal Form and Function in Bufo marinus. Environ Health Persp; in press.], these individuals were examined for gonadal abnormalities, which were significantly and positively associated with percentage of agriculture at the collection site. Thus, we hypothesized the same association for renal abnormalities. We scored gross anatomical abnormalities and used light microscopy to identify tubular and interstitial lesions that have been associated with toxicant exposure in other organisms, including humans. Renal lesions indicative of tubular disease were observed at one suburban and two agricultural sites, whereas interstitial lesions were most severe at one agricultural site. Although there was no relationship between frequency of renal disease and proportion of agriculture in the collection vicinity, the renal lesions we identify are consistent with toxin exposure and are similar to those found in human drug abusers and patients suffering medication-induced nephropathy. This is the first study to describe renal lesions in a wild amphibian species and investigate the distribution of renal lesions across human altered landscapes. Indentifying the chemicals inducing renal lesions across these landscapes, their toxicological mechanisms, and their implications on wildlife health will help us devise strategies to mitigate the impacts of toxins on humans and animals living in human-modified environments. 相似文献
270.
HMI又称人机交互界面,由菜单、控制按钮和页面组成。当设计制作多达几十、上百个页面时,通过编程使如此多的页面一一对应众多按键往往十分繁琐。本文介绍一种页面切换控制方法,不需重复编程来切换页面,使菜单布置更简单,也给后期增添菜单和页面带来方便。 相似文献