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排序方式: 共有407条查询结果,搜索用时 9 毫秒
401.
This article identifies a serious legal gap in current United States Department of Agriculture (USDA) policy concerning decisions about the review and release of biological pest control agents. Currently, most of the critical documents and the quantitative evidence underlying USDA decisions and policy related to the petition, review, and release of biological pest control agents (biocontrols) for weeds are inaccessible. Current practices do not provide sufficient information for biologists or an informed public to understand or evaluate policy decisions and environmental outcomes. The USDA needs to comply with federal law by making all relevant documents and data available on the internet. Federal law and policy requires that the USDA release all relevant information, and make it readily accessible to all interested parties. Public disclosure of all relevant documents, along with the scientific evidence related to the review and release of biocontrols, is required by the Administrative Procedure Act, the Freedom of Information Act, the Federal Advisory Committee Act, the National Environmental Policy Act of 1970, and the Plant Protection Act of 2000. Disclosure of this information will impose at most a trivial financial and administrative burden on the USDA Animal and Plant Health Inspection Service, or the Division of Plant Protection and Quarantine. The importance of full information and open debate in the pursuit of both scientific knowledge and sound environmental management far outweighs any administrative burden.  相似文献   
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Ann Forsten 《Geobios》1978,11(1):31-42
The species of the fossil genus Hipparion found in Bulgaria to this date, and their affinities, are discussed. Of the earlier described 8 different species, only 3 are here considered possibly valid.  相似文献   
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This review is aimed to summarize the experimental researches in the influences of static magnetic field on laboratory rodent models, reported by laboratory scientists, experimental technicians, clinical surgeons, animal veterinarians, and other researchers. Past studies suggested that static magnetic field-singly applied or used combined with other physical or chemical substances-significantly relieved some pains and ameliorated certain diseases in different organ systems, e.g. hypertension, osteoporosis, neuralgia, diabetes and leukemia etc. But on the other hand, some harmful events have also been observed in a number of investigations, from cellular level to fetal development. So exposure to static magnetic field might have dual effects on experimental rodent in various environments, viz. there are potentially therapeutic benefits, as well as adverse effects from it. The positive effect may relate to moderate intensities, while negative influence seems to be in connection with acute strong static magnetic fields. In addition, different orientations of static magnetic field exert different degrees of impact. Thus, the bioeffects of static magnetic field exposure on mice/rats depend on magnetic field intensities, durations and directions, though the exactly relationship between them is still vague. Further researches need to perform with appropriate methodologies, ingenious designs repeatedly and systemically, not only in animal models, but also in human volunteers and patients.  相似文献   
406.
A comprehensive knowledge of the thoracic shape and kinematics is essential for effective risk prevention, diagnose and proper management of thoracic disorders and assessment of treatment or rehabilitation strategies as well as for in silico and in vitro models for realistic applications of boundary conditions.After an extensive search of the existing literature, this study summarizes 45 studies on in vivo thoracic kyphosis and kinematics and creates a systematic and detailed database. The thoracic kyphosis over T1–12 determined using non-radiological devices (34°) was relatively less than measured using radiological devices (40°) during standing. The majority of kinematical measurements are based on non-radiological devices. The thoracic range of motion (RoM) was greatest during axial rotation (40°), followed by lateral bending (26°), and flexion (21°) when determined using non-radiological devices during standing. The smallest RoM was identified during extension (13°). The lower thoracic level (T8–12) contributed more to the RoM than the upper (T1–4) and middle (T4–8) levels during flexion and lateral bending. During axial rotation and extension, the middle level (T4–8) contributed the most. Coupled motion was evident, mostly during lateral bending and axial rotation. With aging, the thoracic kyphosis increased by about 3° per decade, whereas the RoM decreased by about 5° per decade for all load directions. These changes with aging mainly occurred in the lower region (T6–12). The influence of sex on thoracic kyphosis and the RoM has been described as partly contradictory. Obesity was found to decrease the thoracic RoM. Studies comparing standing, sitting and lying reported the effect of posture as significant.  相似文献   
407.
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