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71.
A 9-year-old dog was presented with generalized extensive pulmonary mineralization associated with exertional dyspnea and cyanosis. The differential diagnosis for the pulmonary mineralization included metastaticand dystrophic pulmonary calcification, atypical pulmonary neoplasia, alveolar microlithiasis, idiopathic pulmonary mineralization, and idiopathic pulmonary ossification. The dog was euthanized at the owner's request. The histologic diagnosis was idiopathic pulmonary ossification. No previous report of generalized extensive idiopathic pulmonary ossification was found. Idiopathic pulmonary ossification occurs in man, usually involves a limited area of lung, and is functionally unimportant. The pulmonary ossification in the dog reported here was generalized and associated with severe pulmonary dysfunction. The disease in man and that in the dog in this report do not appear to be directly comparable.  相似文献   
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屏边是我省杉木生产基地之一,其速生丰产技术的研究,对我省用材林的生产发展有着重要意义。本文根据林分密度效应规律,经过统计分析,优化计算,编制该县人工杉木密度管理图,立地指数图表,并对林分适宜密度变化规律及抚育间伐技术等营林措施进行了讨论,精度符合要求,可用于生产。  相似文献   
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Thermolysis of the heterobimetallic phosphinidene complex [Sb(PCy)3]2- Li6.6HNMe2 (Cy = C6H11) at 303 to 313 kelvin gives Zintl compounds containing (Sb7)3- anions. The complex thus constitutes a stable molecular single-source precursor to Zintl compounds and provides a potential low-temperature route to photoactive alkali metal antimonates. The new chemical reaction involved, which is driven thermodynamically by the formation of P-P bonds, has implications in the low-temperature synthesis of other technologically important materials (such as gallium arsenide).  相似文献   
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Clinical isolates (n = 63) of Pseudomonas aeruginosa obtained from various sites in 63 horses were compared using ERIC2 RAPD PCR to determine their genetic relatedness. Resulting banding patterns (n = 24 genotypes) showed a high degree of genetic heterogeneity amongst all isolates examined, indicating a relative non-clonal relationship between isolates from these patients, employing this genotyping technique. This study characterised 63 clinical isolates into 24 distinct genotypes, with the largest cluster (genotype E) accounting for 10/63 (15.9%) of the isolates. ERIC2 RAPD PCR proved to be a highly discriminatory molecular typing tool of P. aeruginosa in isolates recovered from horses. With the adoption of several controls to aid reproducibility, this technique may be useful as an alternative to PFGE, particularly in epidemiological investigations of outbreaks where speed may be a significant parameter. This is the first report of clonal heterogeneity amongst P. aeruginosa from horses and demonstrated that ERIC RAPD PCR is a rapid method for the examination of this species in horses, which may be useful in outbreak analysis.  相似文献   
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Osmium isotopic analyses of picritic lavas from Hawaii show enrichments in the osmium-186/osmium-188 ratio (186Os/188Os) of 0. 008 to 0.018%, relative to a chondritic upper mantle, that are positively correlated with enrichments in 187Os/188Os of 5.4 to 9.0%. The most viable mechanism to produce these coupled 186Os and 187Os enrichments is by addition of 0.5 to 1 weight percent of outer core metal to a portion of the D" layer and subsequent upwelling of the mixture. These data suggest that some plumes originate at the core-mantle boundary and that Os isotopes may be used to distinguish plumes derived from shallow versus deep mantle sources.  相似文献   
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A paramyxovirus virus termed Nipah virus has been identified as the etiologic agent of an outbreak of severe encephalitis in people with close contact exposure to pigs in Malaysia and Singapore. The outbreak was first noted in late September 1998 and by mid-June 1999, more than 265 encephalitis cases, including 105 deaths, had been reported in Malaysia, and 11 cases of encephalitis or respiratory illness with one death had been reported in Singapore. Electron microscopic, serologic, and genetic studies indicate that this virus belongs to the family Paramyxoviridae and is most closely related to the recently discovered Hendra virus. We suggest that these two viruses are representative of a new genus within the family Paramyxoviridae. Like Hendra virus, Nipah virus is unusual among the paramyxoviruses in its ability to infect and cause potentially fatal disease in a number of host species, including humans.  相似文献   
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