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1.
A 6-mo-old female scarlet macaw (Ara macao) was presented after a 2-mo period of anorexia and weakness. The bird was reluctant to fly 1 wk before referral due to a painful left wing. Physical examination revealed a firm swelling around the left shoulder. On radiographs, the diaphysis and proximal metaphysis of the left scapula were radiolucent. Computer tomography revealed an osteolytic process, suggestive of a bone tumor, affecting the left scapula. Cytology of a fine needle aspiration biopsy of the mass showed erythrocytes, a proliferation of spindle-shaped mesenchymal cells, and multinucleated giant cells (osteoclasts) suggestive of a giant cell tumor. The left wing, including the scapula, was amputated. The bird showed a fast recovery but died 1 hr later. Findings during the pathological examination were compatible with shock due to blood loss. The shoulder process was characterized as a giant cell tumor. To our knowledge, this is the first complete report of a giant cell tumor of the bone in a bird.  相似文献   
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Muscles from male and female C57BL/6J Chediak-Higashi syndrome (CHS) and phenotypically normal mice with the bgJ allele were studied microscopically and histochemically for the presence of basophilic cytoplasmic structures seen by other investigators in muscles of CHS mice of the SB/Le strain. Triceps brachii, gastrocnemius, quadriceps femoris, and biceps femoris muscles were examined. Multiple basophilic cylindrical lesions were present in hematoxylin and eosin-stained muscle from all groups. Lesions were positive for esterase, Sudan black, and periodic acid-Schiff. Lesions were only seen in type II muscle fibers. Type I muscle cells comprised less than an estimated 5% of the total muscle fibers in the four muscles examined. Scores were assigned based on the presence or absence of lesions in each muscle. Male mice of both phenotypes had significantly more lesions (P less than 0.05) than female mice. When sexes were combined, lesions were significantly (P less than 0.05) more numerous in normal mice than CHS mice for all muscles except the gastrocnemius. Lesions were significantly (P less than 0.05) more numerous in the phenotypically normal male than the CHS male mice for the triceps and quadriceps muscles. There was no significant difference (P greater than 0.05) between lesions of phenotypically normal female and female CHS mice. Basophilic cytoplasmic structures did not prove to be a manifestation of the CHS trait.  相似文献   
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Accurate emission inventories are crucial for informed decisions about emission control strategies. Emission inventory activities are now well established throughout the world and a large body of resources is available to assist in estimating emissions at the global, regional and local scale. Work is ongoing to refine methodologies and to address additional sources and pollutants such as fine particulate matter. During the last decade innovative concepts for emission control legislation were developed. Market based instruments can achieve envisaged emission reductions at lower costs than conventional approaches. Air quality management is now understood as a multi-pollutant, multi-effect task, which offers a significant cost saving potential if synergistic effects are fully utilized. Integrated assessment models proved useful in managing the vast volume of relevant information needed for the design of cost-effective emission control strategies. Europe and North America have embarked on ambitious control strategies that will lead to significant reductions in the emissions of some of the conventional pollutants (e.g., SO2, NOx, VOC). There are also first indications of a structural break that could reverse the long-term growth trend of SO2 emissions also in the fast developing nations of Asia.  相似文献   
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In order to contribute to the analysis and solution of regional scale environmental problems in East Asia, we developed a tool for the comprehensive assessment of alternative policy options to improve air quality. This tool projects the future regional energy supply, calculates the emission levels of sulfur dioxide and estimates the geographical pattern of sulfur deposition resulting from emissions. Sulfur deposition in Japan through 2030 was forecasted for various energy supply and emission control scenarios using the analysis tool. Future sulfur depositions were calculated from the source-receptor matrix for 1995 and the growth rate of emission for the source subregion. In the case of the current legislation scenario, anthropogenic SO2 emissions in East Asia would grow by 34 percent and sulfur deposition in Japan would increase by approximately 20 percent between 1995 and 2030. This increase in sulfur deposition over these 35 years is sligthly less than the contribution from volcanic emission to sulfur deposition in Japan. In the case of the hypothetical dirty scenario for China, sulfur deposition in several grids which face the Sea of Japan would double by 2030.  相似文献   
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Klimont  Z.  Cofala  J.  Schöpp  W.  Amann  M.  Streets  D.G.  Ichikawa  Y.  Fujita  S. 《Water, air, and soil pollution》2001,130(1-4):193-198
Starting from an inventory of SO2, NOx, VOC and NH3 emissions for the years 1990 and 1995 in East Asia (Japan, South and North Korea, China, Mongolia and Taiwan), the temporal development of the emissions of the four air pollutants is projected to the year 2030 based on scenarios of economic development. The projections are prepared at a regional level (prefectures or provinces of individual countries) and distinguish more than 100 source categories for each region. The emission estimates are presented with a spatial resolution of 1×1 degree longitude/latitude. First results suggest that, due to the emission control legislation taken in the region, SO2 emissions would only grow by about 46 percent until 2030. Emissions of NOx and VOC may increase by 95 and 65 percent, respectively, mainly driven by the expected increase in road traffic volume. Ammonia, mainly emitted from agriculture, is projected to double by 2030.  相似文献   
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Effects of season and photoperiod on the anterior pituitary gland and testes were studied by responses to exogenous GnRH. Stallions were assigned to one of three treatments: 1) control, exposed to natural day length; 2) S-L, 8 h of light and 16 h dark (8:16) for 20 wk beginning July 16, 1982 then 16:8 from December 2, 1982 until March 5, 1984; or 3) S-S, 8:16 from July 16, 1982 until March 5, 1984. Approximately every 8 wk, stallions were administered GnRH (2 micrograms/kg BW) and blood was sampled at 20-min intervals for 2 h before and 8 h after GnRH administration. Concentrations of LH, FSH and testosterone were determined. Baseline concentrations (mean of pre-GnRH samples) of all hormones fluctuated seasonally (P less than .05), but only LH and testosterone displayed seasonal changes (P less than .05) in maximum response to GnRH (highest concentration above baseline after GnRH). The FSH response to GnRH was not affected (P greater than .05) by season, photoperiod or the season X treatment interaction. Exposure of S-L stallions to 16:8 in December resulted in early recrudescence of baseline concentrations of LH, FSH and testosterone. Maximum concentration of testosterone in response to GnRH was stimulated by 16:8, but the increase in baseline LH concentrations in S-L stallions was not associated with an increase in maximum LH response to GnRH. Seasonal patterns of baseline concentrations of FSH and testosterone and maximum LH response to GnRH in S-S stallions were similar to those for control stallions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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