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排序方式: 共有1763条查询结果,搜索用时 31 毫秒
1.
Environmental chemicals comprise a major portion of the human exposome, with some shown to impact the health of susceptible populations, including pregnant women and developing fetuses. The placenta and cord blood serve as important biological windows into the maternal and fetal environments. In this article we review how environmental chemicals (defined here to include man-made chemicals [e.g., flame retardants, pesticides/herbicides, per- and polyfluoroalkyl substances], toxins, metals, and other xenobiotic compounds) contribute to the prenatal exposome and highlight future directions to advance this research field. Our findings from a survey of recent literature indicate the need to better understand the breadth of environmental chemicals that reach the placenta and cord blood, as well as the linkages between prenatal exposures, mechanisms of toxicity, and subsequent health outcomes. Research efforts tailored towards addressing these needs will provide a more comprehensive understanding of how environmental chemicals impact maternal and fetal health. 相似文献
2.
中老年人前列腺体积增长的城乡差异 总被引:27,自引:1,他引:26
为了解国人中年以后前列腺的生长情况及其可能的影响因素,对北京、河北、湖北等地四个社区的城乡居民前列腺体积进行了经腹B超测量。结果表明城区居民的前列腺体积明显大于相应年龄段的农村居民,城区居民的前列腺增长速率比农村居民高二倍。生活环境和饮食习惯的不同可能为其原因之一。 相似文献
3.
R. James 《Journal of Renal Care》2007,33(3):119-123
Dialysis, with its high dependence upon technology, disposable products and transport requirements, presents an unusual perspective for environmental management. This study considers and compares the environmental aspects arising from the provision of haemodialysis (HD) in the hospital and home setting. Resource items were measured at two levels of aggregation — unit and individual patient. Unit level items applied to common resources used for HD and require apportioning appropriately with patient level items that could be attributable to individuals. The data was measured in standard units such as hours and number of treatments or apportioned appropriately. With equivalent emissions calculated as CO2 annually per patient for standard HD. The findings indicate that HD in the home offers a net reduction in CO2 emissions per patient annually compared to hospital based HD, and provides an overview of how healthcare provision and the use of resources can be measured, enabling refinement in environmental management plans. 相似文献
4.
Effect of environment on extremely severe road traffic crashes:retrospective epidemic analysis during 2000-2001 总被引:1,自引:0,他引:1
Objective: To make an epidemiological analysis of the effect of environment on extremely severe road traffic crashes (RTCs). Methods: Epidemiologic data of extremely severe RTCs associated with environmental factors, including weather, topography, road conditions and other traffic conditions in Mainland China during 2000-2001, were collected and analyzed. Results: ( 1 ) During 2000-2001, there were 3 365 extremely severe RTCs with 13 666 deaths, 12 204 injuries and a direct economical loss of 136 million RMB. ( 2 ) Most extremely severe RTCs occurred in fine weather days and in the daytime. The high occurrence sites were plain areas, horizontal and straight roads, Grade B and C roads, ordinary road segment, and asphalt, smooth and mixed roads. (3) Compared with other RTCs, extremely severe RTCs were more likely to happen under following conditions: on cloudy, snowing, misty and blustering days; in hill and mountainous areas; on crooked and sloping roads; on freeway, Grade A, B, and C roads; mixed roads; ordinary, bridge, narrow and transitional roads; sand and dirt-roads; without traffic control measures; night without lighting. (4) Extremely severe RTCs of mountainous area or crooked and sloping roads were most severe in terms of deaths and injures per crash. Conclusions: Extremely severe RTCs are closely related with environmental factors. Rational road programming, enhancing road establishment and improving road conditions are probably effective measures to reduce the road traffic injuries. 相似文献
5.
Stressors in ICU: patients’ evaluation 总被引:3,自引:0,他引:3
M. A. F. P. Novaes A. Aronovich M. B. Ferraz E. Knobel 《Intensive care medicine》1997,23(12):1282-1285
Objective: To study the physical and psychological stressors in the intensive care unit (ICU) and to correlate stressors with different
demographic variables. Design: Cross-sectional analytical survey. Setting: Intensive care unit of a private hospital. Patients and participants: 50 randomly selected ICU patients during the first week of their ICU stay. Measurements and results: The Intensive Care Unit Environmental Stressor Scale was administered to 50 patients. Pain and the impossibility of sleeping
due to noise and having tubes in the nose and mouth were considered the most important physical stressors. Loss of self control
and lack of understanding about the attitudes and procedures were the main psychological stressors. Conclusions: Interventions should be aimed at relieving the patient's pain and at controlling the level of noise to make sleep possible.
From the psychological standpoint, the independence of the patient should be encouraged, thus stimulating the recovery of
self-control. The team should also inform the patient about the procedures which will be carried out.
Received: 1 April 1997 Accepted: 24 September 1997 相似文献
6.
The Physical Inactivity Matrix: Lessons from the classification of physical inactivity interventions
Kypros Kypri Alex Donaldson Elizabeth Johnstone 《Journal of Science and Medicine in Sport》2006,9(1-2):98-102
Physical inactivity (PI), a leading modifiable cause of disease and injury, is endemic in industrialised nations. Although considerable research has been undertaken in this field, we lack a system to synthesise the research literature to inform policy and identify research needs. The aims of this study were to (1) develop a system to classify physical inactivity intervention studies, (2) examine the distribution of PI interventions published in the peer-reviewed health literature using the system, and (3) consider implications for future research. We developed the Physical Inactivity Matrix (PIM), with 12 intervention points, created by the intersection of two dimensions: the intervention target (individual, physical environment and social/cultural environment) and the activity focus (transport, work/school, leisure and consumer). A formal search of the health research literature identified 529 eligible studies and each was classified into one of the 12 cells of the PIM. Most studies were categorised as: individual-leisure (68%), individual-work/school (12%) or social/cultural environment-leisure (13%). Only 4% targeted the physical environment. The findings of this initial application of the PIM support the call for greater investment in policies, interventions and research that focus on the relationship between the environment and PI, and transportation in particular. There would be merit in establishing the inter-rater reliability of the PIM and applying it to a wider variety of studies, including those published in the transportation and urban planning literatures. The PIM could be a useful tool for monitoring trends in research directions and funding levels over time and across countries. 相似文献
7.
云南阳春砂仁的质量与生态环境关系的探讨 总被引:7,自引:0,他引:7
当前云南阳春砂仁产量,占全国总产量的65.5%,商品有左右全国砂仁市场之势。经调查云南产区生态环境较原产区广东阳春县为优,故表现出植株生长较高,果实较大,每室籽粒数较多等性状特征之差,这些差异并非是物种的变异,而是生态环境较好所致。从两地商品中的精油成分和微量元素分析结果也基本一致,认为影响云南阳春砂仁质量的酸味,两地商品均有,并都来源于假种皮,只不过云南商品果实较大,假种皮较厚,总酸含量较高,但是总酸均为无毒副作用的低分子有机酸,不影响砂仁的质量。因此我们认为云南引种区的阳春砂仁质量,与广东原产区的阳春砂仁质量应基本一致。 相似文献
8.
Esther Kahana Nelly Zilber Joseph H. Abramson Victor Biton Yaffa Leibowitz Oded Abramsky 《Journal of neurology》1994,241(5):341-346
The incidence and prevalence of multiple sclerosis (MS) were compared, controlling for age, in native-born Israelis of different origins and in immigrants to Israel. This comparison was carried out in two populations, countrywide and in Jerusalem. In the countrywide population, ascertainment was based mainly on hospitalizations; it included 252 patients who were native-born and 150 who had immigrated from Africa-Asia (AA immigrants). The 89 MS patients of Jerusalem also included patients diagnosed in outpatient clinics. In native-born Israelis whose father was born in Europe-America (I-EA), the incidence and prevalence of MS were found to be as high as or even higher than that found previously in immigrants from Europe-America. Among native-born Israelis whose father was born in Africa or Asia (I-AA), the yearly age-adjusted incidence and prevalence rates were found to be 1.4- to 1.8-fold higher than among AA immigrants, pointing to environmental factors. The incidence and prevalence rates in the I-EA were 1.2- to 1.6-fold higher than in the I-AA, pointing to genetic factors. These results seem to point to both environmental and genetic factors in the aetiology of MS. Further research is needed, however, to disentangle the genetic factors from possible environmental differences in the two ethnic groups. 相似文献
9.
10.
Kenefick RW Mahood NV Hazzard MP Quinn TJ Castellani JW 《European journal of applied physiology》2004,92(4-5):565-570
Hyperosmotic hypovolemia impairs vasoconstriction during sedentary cold exposure. The purpose of this study was to determine whether hypohydration alters thermoregulation and cardiovascular responses to exercise in cold air. On four occasions, eight males [35.1 (2.7) years, 175.5 (3.1) cm, 73.3 (2.6) kg, 57.2 (2.6) ml kg–1 min–1 maximal oxygen uptake (O2max), 19.6 (2.4)% fat] walked, in t-shirt, shorts, and shoes, at 50% O2max, for 60 min in either a 4°C (Cold) or a 25°C (Temperate) environment in both hypohydrated state (HYPO, –4% body mass) and euhydrated state (EU). During exercise–cold stress, rectal temperature (Tre), mean weighted skin temperature, heart rate (HR), cardiac output (CO), and stroke volume (SV) were measured every 20 min. Mean weighted skin temperature values were not different between HYPO and EU but were lower (P<0.05) in Cold versus Temperate trials. Tre was not different (P>0.05) between HYPO–Cold and EU–Cold. CO and SV were not different within hydration states and were not different between Cold and Temperate trials (P<0.05). HR was not different between HYPO–Cold and EU–Cold. These data demonstrate that moderate intensity exercise in the cold while hypohydrated does not alter metabolic heat production, skin temperatures and heat loss, nor does it increase thermoregulatory and cardiovascular strain. 相似文献