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排序方式: 共有4150条查询结果,搜索用时 15 毫秒
1.
Lead content of rice collected from various areas in the world 总被引:1,自引:0,他引:1
ZW Zhang CS Moon T Watanabe S Shimbo M Ikeda 《Canadian Metallurgical Quarterly》1996,191(1-2):169-175
Rice samples consumed by local populations were collected between 1990 and 1995 in 17 areas in the world, mostly from Asia (10 areas), but also from 7 areas outside of Asia. In total, 1528 samples were obtained (about one half from Japan) and were analyzed for lead (Pb) by electrothermal atomic absorption spectrometry. When the Pb contents in rice samples were classified into 10 areas in Asia, the highest and the lowest geometric means (GMs) were for Indonesia (38 ng/g) and Australia (2 ng/g), respectively. Among 7 regions outside Asia, the GM was highest for Spain (58 ng/g) and the lowest for the USA. (3 ng/g). Moreover, inter-regional differences were significant, when more than 100 samples from one area were divided into 3-9 regions and GMs for regions were compared. There was a marked difference in Pb contents in rice by areas and regions in the world. Nevertheless, comparison by area of the present results with those reported in literature show that there has been no substantial reduction in Pb in rice in the past decade either in Japan or elsewhere in the world. 相似文献
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Pre-transplant nephrectomy was done in a 25-year-old man for calculous pyelonephritis using a retroperitoneal laparoscopic approach with a newly devised ligature applicator-dissector- kidney retractor. 相似文献
4.
DL Arnold PF McGuire D Miller S Malcolm S Hayward A Paquet 《Canadian Metallurgical Quarterly》1998,36(9-10):771-779
Two experiments with Sprague Dawley rats tested their ability to hydrolyse myristoyl-methionine (M-M) into myristic acid and L-methionine (M). In the first experiment, lasting for 3 days. male rats were orally administered [9,10-3H]myristoyl-L-[35S]methionine. The recovery of radioactivity was approximately 90% for both isotopes; 19% of the administered 3H was recovered in the urine and 16% in the faeces, while the recovered 35S activity was 13 and 12%, respectively. The balance of the radioactivity was found among the tissues, organs and blood. In the second experiment, male and female rats received soybean-based diets which were supplemented with either 0.305% M-M or 0.2% M (both diets contained equal amounts of M) for periods up to 4 weeks. The growth rate of the rats receiving the 0.305% M-M diets was slightly slower than that for the rats on the 0.2% M diet, but the difference was not statistically significant (P > 0.05). The M-M rats had a transitory decrease in feed consumption, suggesting that palatability may have contributed to the growth difference and that a somewhat greater amount of M-M was necessary for the rat to attain the same growth rate as that produced by 0.2% M. When the amount of dietary M-M was increased to 3.05% M-M, a greater reduction in feed consumption and body weight gain was observed. This latter diet was an initial attempt to study the potential toxicity of M-M. None of the haematological, clinical chemistry or organ weight data suggested that M-M was overtly toxic per se, but longer-term feeding studies are needed to evaluate the potential toxicity of M-M more fully. 相似文献
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E Bazopoulou-Kyrkanidou P Neou CS Bartsocas S Kyrkanides I Fanourakis 《Canadian Metallurgical Quarterly》1995,6(3):227-232
PURPOSE: To select ideal radiologic projections for mapping and ablation of tachycardias of right ventricular outflow tract (RVOT). METHODS: Ten hearts from human corpses were studied utilizing radiopaque material to identify the pulmonary valve and three distinct sites on this valve: septal anterior (A), septal posterior (P) and free-wall (L). Next, the hearts were filmed in the frontal plane and in oblique projections with 15 degrees increments to the right and to the left. The projections in which the sites were lateralized on the valve, eased radiologic interpretation and were considered ideal for mapping and ablation. Depending on the proximity of the sites to the lateral extremes of the pulmonary valve, the projections were considered ideal ( ), intermediary (++) and inadequate (+). RESULTS: Projections [table: see text] CONCLUSION: The A site of RVOT was best indicated in the 60 and 45 degrees left anterior oblique projections; the 0 degree postero anterior projection was best for mapping the P site; the L region was best explored in the 60 degrees right anterior oblique projection. 相似文献
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Jianxin Wei Mark R Pickering Michael R Frater John F Arnold John A Boman Wenjun Zeng 《IEEE transactions on image processing》2005,14(8):1033-1042
It is well known that tile-boundary artifacts occur in wavelet-based lossy image coding. However, until now, their cause has not been understood well. In this paper, we show that boundary artifacts are an inescapable consequence of the usual methods used to choose tile size and the type of symmetric extension employed in a wavelet-based image decomposition system. This paper presents a novel method for reducing these tile-boundary artifacts. The method employs odd tile sizes (2N + 1 samples) rather than the conventional even tile sizes (2N samples). It is shown that, for the same bit rate, an image compressed using an odd tile length low-pass first (OTLPF) convention has significantly less boundary artifacts than an image compressed using even tile sizes. The OTLPF convention can also be incorporated into the JPEG 2000 image compression algorithm using extensions defined in Part 2 of this standard. 相似文献
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We discuss some different ideas about the sort of formalism appropriate for translation (more specifically, transfer) that have been explored within Eurotra. The intention is not to evaluate these different ideas, but to outline the issues of general interest and relevance that they raise. Section 1 describes some common assumptions, section 2 describes the different ways they have been interpreted, and section 3 considers some further implications. 相似文献
10.
The occurrence of fungi was investigated in the gut of 200 common garden lizards (Agama agama). The most important pathogenic fungus isolated was Basidiobolus haptosporus, an aetiological agent of subcutaneous zygomycosis. It was recovered from the intestinal contents of 112 (56%) lizards. Other important fungi isolated included Aspergillus spp. in 24 (12%) lizards, Candida spp. in 12 (6%), Penicillium spp. in 12 (6%) and Fusarium spp. in 12 (6%). Mucor spp. were isolated from eight (4%) male lizards only. Agamid lizards are plentiful in rural and urban areas of Nigeria. As they live in close vicinity to man, they are likely to play an important role in the spread of disease that may be caused by these fungi and its transmission to man. None of the animals investigated that yielded fungal cultures revealed any external fungal infection. 相似文献