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991.
992.
Hugh Clapin Katherine Neal John Wennerbom Barbara Nunn Deborah Dysart Andy Pickering Lisa Featherstone Hiram Caton Dale Jacquette Laura Ruetsche William A. Turner Cornelia Lüdecke Birgit Lohmann James Ladyman Jonathan Coopersmith David Oldroyd Dennis Dean Michael Ruse Nicolas Rasmussen William N. Kaghan Martin Bridgstock Geoffrey Cocks Stephanie H. Kenen Ivan Crozier Sokhieng Au Desmond Barrett Mark Cortiula Ian D. Lawrie 《Metascience》2001,10(1):50-149
993.
N. Vleduts-Stokolov 《Information processing & management》1982,18(6):313-321
The paper describes a technique developed as automatic support to subject heading indexing at BIOSIS. The technique is based on the use of a formalized language for semantic representation of biological texts and subject headings—the language of Concept Primitives. The structure of the language is discussed as well as the structure of the Semantic Vocabulary, in which natural language words from biological texts are described by Concept Primitives. The Semantic Vocabulary is being constructed. Approximately 8,000 entries corresponding to high frequency significant words have been compiled, comprising at least three-quarters of the final number. Results of experiments checking the approach are given, and journal/subject heading and author/subject heading correlation data are analyzed to be used as a supporting technique. 相似文献
994.
M. I. Akpanabiatu I. B. Umoh E. O. Udosen A. E. Udoh E. E. Edet 《Indian journal of clinical biochemistry : IJCB》2005,20(2):29-34
Aqueous extract of the leaf and root ofNauclea latifolia Sm. (Rubiaceae) is used in Nigerian folk medicine for the treatment of hypertension. This work is carried out to investigate
the effect ofNauclea latifolia leaf extract on lipid profile and cardiovascular activity of rats. Normal and 10% coconut oil fed rats were treated with
the water-soluble fraction of the ethanol extract ofNauclea latifolia leaf for 2 weeks. Forty-eight mature male albino rats of the Wistar strain were divided into two experiments of four groups,
each group having 6 animals. Experiment I animals were treated with the water-soluble fraction of the ethanol extract whilst
experiment II animals were fed 10% coconut oil meal before treatment with the water-soluble fraction of the ethanol extract.
A single oral dose ofNauclea latifolia was 170, 340 and 510 mg/kg body wt/day of the extracts respectively for 2 wks. There was no significant change in the lipid
profile of the experimental animals as compared with the controls. There was about 40% relaxation on contracted thoracic aorta
that was pre-contracted with 2 μM phenylephrine. The viability of the tissue was tested against 10 μM of acetylcholine. There
was no significant (P>0.05) change in Na+ concentration in the serum. However, the K+ concentration in the serum of the experimental animals showed a significant increase. The study shows that ethanol extract
ofNauclea latifolia has vasodilator action on the aorta and that lipid profiles of experimental rats were not affected. Furthermore, the increase
in the K+ may be contributing to the vasodilator effect ofNauclea latifolia. 相似文献
995.
This paper presents findings from an analysis of the determinants of the formation of university spin-off companies within the university's research park. We find that university spin-off companies are a greater proportion of the companies in older parks and in parks that are associated with richer university research environments. We also find that university spin-off companies are a larger proportion of companies in parks that are geographically closer to their university and in parks that have a biotechnology focus. 相似文献
996.
N.H. Farhat 《Journal of The Franklin Institute》1973,296(6):393-402
The advantages of real-time microwave holography are reviewed. Real-time capabilities require real-time acquisition of the raw hologram data and real-time retrieval of images from the collected data. This paper examines in detail the acquisition of microwave hologram data by double circular scanning of a single reciever in the context of quasi real-time operation. The principle of the double circular scan is presented and the effect of this sampling format on the retrieved image analyzed. Optical bench simulation of hologram recording employing this sampling format is also presented. It is shown that such a scanning format has the attractive properties of economy, speed (?1 holographic frame/sec) and excellent retrieved image quality. Finally, the compatibility of the double circular scan format with scanned transmitter-receiver holography is discussed in the context of practical low-cost systems. 相似文献
997.
998.
膝关节受伤以后,最早出现萎缩的肌肉是股四头肌内侧头。足球运动员膝关节伤病多,所以对其股四头肌肌粗值进行定量分析,具有实际意义。以体表形态数据建立数学模型,推导出股四头肌肌粗值,建立了统一的对比衡量标准。肌粗值的变化,首先是受髌骨上5cm 外缘腿围影响,其次是受髌中围的影响,相关程度分别为高度相关和低度相关,而肌粗值与髌骨上10cm 外缘腿围间变化呈不相关。 相似文献
999.
In our target article (Dempster & Corkill, 1999a) we presented an overview of recent work on interference and inhibition in cognition and behavior. The commentators provided highly informative feedback about a range of implications of this new body of work for educational psychology, including learning disabilities. In our response to the commentators, we reply to two relatively broad topics they touch on: consciousness and the functionalist tradition of American psychology. We also remark on two relatively narrow issues raised by the commentators: what constitutes irrelevant information and perseveration in the missing addend task. 相似文献
1000.
Joan I. Vondra Daniel S. Shaw Laure Swearingen Meredith Cohen Elizabeth B. Owens 《Early education and development》1999,10(2):163-190
The aim of this investigation was to examine the role of social relationships in the home as predictors of social functioning in the first years of school. Longitudinal data gathered on 156 children from urban, low-income families were used to examine the unique contributions of mother-child attachment classification at ages 1 and 2 years, the child's relationship with another adult caregiver, the child's closeness to a sibling, and the child's status in the family relative to siblings between ages 3 and 4 years, to teacher reports of their own relationship to the child and the child's social skills in the classroom and peer relations. The role of family-based relationships as possible protective factors for children at social or demographic risk for problems in school was also tested. Results indicate that quality of different family relationships provides relatively independent and complementary information about early social functioning in school, with more limited evidence for compensatory or protective processes at work. 相似文献