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The aim of this study is to estimate the reference level of lifetime cadmium intake (LCd) as the benchmark doses (BMDs) and their 95% lower confidence limits (BMDLs) for various renal effects by applying a hybrid approach. The participants comprised 3,013 (1,362 men and 1,651 women) and 278 (129 men and 149 women) inhabitants of the Cd‐polluted and nonpolluted areas, respectively, in the environmentally exposed Kakehashi River basin. Glucose, protein, aminonitrogen, metallothionein, and β2‐microglobulin in urine were measured as indicators of renal dysfunction. The BMD and BMDL that corresponded to an additional risk of 5% were calculated with background risk at zero exposure set at 5%. The obtained BMDLs of LCd were 3.7 g (glucose), 3.2 g (protein), 3.7 g (aminonitrogen), 1.7 g (metallothionein), and 1.8 g (β2‐microglobulin) in men and 2.9 g (glucose), 2.5 g (protein), 2.0 g (aminonitrogen), 1.6 g (metallothionein), and 1.3 g (β2‐microglobulin) in women. The lowest BMDL was 1.7 g (metallothionein) and 1.3 g (β2‐microglobulin) in men and women, respectively. The lowest BMDL of LCd (1.3 g) was somewhat lower than the representative threshold LCd (2.0 g) calculated in the previous studies. The obtained BMDLs may contribute to further discussion on the health risk assessment of cadmium exposure.  相似文献   
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Summary A cattle population presents three spatial patterns according to their behaviour. These patterns are as follows: the random spatial pattern which occurs when the cattle move during grazing (feeding), the aggregated spatial pattern which occurs when they rest, and the regular or quasi-regular spatial pattern which occurs when they separate into two or more subgroups. In this study, these three states of behaviour were represented by a mathematical model, and a method to test the pattern statistically was derived.  相似文献   
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Infants born very preterm (PT), prior to 32 weeks gestation, are at increased risk of developing cerebral palsy. Children with spastic cerebral palsy have impaired selective leg joint movement, which contributes to lifelong walking limitations. We investigated whether infants born PT generated more selective hip–knee joint movement (e.g., hip flexes as knee extends) while participating in a scaffolded mobile task. Infants born PT and infants born full-term (FT) at 4 months corrected age participated in a scaffolded mobile task for 2–3 consecutive days. The scaffolded mobile task required infants to raise their legs vertically over a virtual threshold. Three threshold heights (low, middle, and high) were used to test whether the middle and high heights encourage infants to move their legs more selectively. Fifteen infants born FT learned the task and showed more selective hip–knee movement at each of the three threshold heights on the day that they learned, compared with their baseline spontaneous kicking. Thirteen infants born PT learned the task and showed more selective hip–knee movement on their learning day, but only when the middle and high thresholds were used. The results show that the scaffolded mobile task effectively encouraged infants to generate more selective hip–knee joint movement.  相似文献   
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从比较信托法看中国信托法的立法及其解释   总被引:2,自引:0,他引:2  
《中华人民共和国信托法》是亚洲第五部信托法 ,它在总体上是肯定的 ,但仍有一些值得商榷的地方。首先 ,从立法角度看中国信托法的条文 ,其定义非常明确 ,它构筑了信托的基本结构 ,但有一些不完善的地方需要改进 ;其次 ,从释义方面看中国信托法的条文 ,其内容不同程度地存在不周全的地方 ,在释义时容易使人产生误解 ,应该规定得更加明确和严密 ;再次 ,从经济方面看信托活用的效用 ,信托作为财产管理的制度具有无穷的效用 ,应该“用活”信托制度。  相似文献   
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The racial characteristics of children adopted from abroad by American parents have fluctuated sharply over time in response to changing legislation and attitudes toward intercountry adoptions in the United States and the sending countries. This study investigates how the likelihood of parents adopting a White versus non-White child varies by the characteristics of the adopted child, the parents, and the household. Our analyses, using the 2008–2012 American Community Survey, show that parents consider the child's age, sex, and health; the presence of adopted and biologically related children in the household; and shifts in the availability of children across major sending countries.  相似文献   
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Prior research supports that infants born very preterm (PT), compared with full term (FT), have early differences in rate of learning and motor control that may hinder their ability to learn challenging motor tasks. Four-month-old infants born FT (= 18) and PT (n = 18) participated in an infant kick-activated mobile task that was scaffolded to motivate progressively higher kicks. We found the FT group learned the association between their leg movements and mobile activation on the second day, but the PT group learned the association on the third day. Both groups of infants increased the height of their kicks on the day they learned the task, compared with their spontaneous kicking height. These findings suggest that infants born PT have the ability to learn challenging motor tasks, such as kicking high, when participating in a task environment that uses scaffolding.  相似文献   
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Complex systems often involve a huge number of variables whose interdependence must be taken into account. This makes the adoption of an integrated approach essential for the proper management of a wide range of aspects related to human life, from social matters to the environment. In particular, this paper takes into consideration three different experiences in which the use of an integrated approach represented the most effective response for managing the evolving realities we took into consideration. We focused on the issue of land management, with particular attention to the problem of monoculture in Brazil. Then we analyzed the attempted cooperation between the States of the Aral Sea area for efficient water management of the basin and, finally, we dealt with the matter of energy efficiency and how the production of home integrated systems could lead to a better rationalization of energy consumption in the near future.   相似文献   
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