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41.
AIM: To describe the histopathology of a previously unrecorded canine disease and deduce the cause of the lesions. METHODS: Formalin-fixed tissues were processed into paraffin wax and epoxy resin for light and electron microscopy of variously stained sections of liver, brain, heart muscle and kidney. RESULTS: Periodic acid Schiff (PAS) -positive bodies in liver and myocardium were typical of a polyglucosan body disease. Neurons contained coarse granular material that stained similarly to the polyglucosan bodies. CONCLUSION: The nature, distribution and histochemistry of lesions observed are consistent with a putative diagnosis of Glycogen storage disease type IV, an inherited metabolic defect associated with a deficiency of glycogen-branching enzyme not previously reported in dogs.  相似文献   
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The concentration of 1, 2-dibromoethane (EDB) gas in the air space during fumigation can be expressed by the empirical equation c = exp [k(t+ I)b]. In this equation c is the concentration of EDB in g/m3 and t is the lapsed time in minutes; k is the natural log of the nominal dosage and b is a parameter which depends on the contents of the fumigation chamber. The b value is obtained from the linear relationship In [(In c)/k] = b In (t+1). The concentration-time product is obtained from the integral   相似文献   
44.
近年来,围绕核心期刊存与废的争论,一直是图书情报界、学术界和出版界的热门话题,引起业内人士的极大关注。核心期刊的推出缘何会造成如此大的影响?究其原因,主要是由于核心期刊功能的延伸和强化,特别是在成果认定、期刊评价方面的广泛应用,直接影响到期刊编者、作者等诸多方面的利益,因此人们会从各自不同的角度对它持有不同看法。本文分析和探讨了核心期刊概念引发的问题。  相似文献   
45.
An adult male Eastern Grey kangaroo from a wildlife reserve near Melbourne was submitted for necropsy examination and was discovered to have abnormal dentition. There was no evidence that any premolars or molars had ever been present on the right mandible, whilst the incisors were normal. The age of the kangaroo was estimated to be 1 year 9 months using the right maxillary molars and 2 years 4 months old using the contralateral side, presumably due to the asymmetry of the dental arcades. 'Lumpy jaw', a common periodontal disease of kangaroos, from which Bacteroides sp was cultured, was present on the base of the vertical ramus of the left mandible. Complete unilateral absence of premolar and molar teeth in the mandible of a kangaroo has not been described. This condition affected molar progression in both sets of maxillary molars.  相似文献   
46.
Selection pressure with the acaricide, amitraz was applied to a strain of Rhipicephalus (Boophilus) microplus (Canestrini) in 13 out of 18 generations, resulting in a 28.7-fold increase in resistance, indicating a shift in the phenotypic composition of the ticks, from a heterogenous mixture of both susceptible and resistant ticks when selection began to a homogenous composition of predominantly resistant ticks when selection ended. Resistant larvae of the last selected generation were infested on cattle three separate times at 20, 13, and 6 d (7 d intervals) before being dipped in a total immersion vat charged at 0.02, 0.044, and 0.096% active ingredient (AI) amitraz. There was a dose related, though not always significant, response to amitraz whereby each increase in concentration produced increased adverse effects. The number of ticks and index of fecundity (IF) of females recovered from cattle treated at 0.02 and 0.044% AI were not different from that of untreated ticks. However, female weight and egg mass weight of females recovered from cattle treated at 0.044% were lower than untreated females or females treated at 0.02% AI. All measured parameters obtained from ticks recovered from cattle treated at 0.096% AI were significantly lower than the untreated control group, but tick numbers and IF were not different from the other treated groups. At 0.02% AI the level of control was significantly lower (34.6%) than treatment at 0.096% AI (81.2%), while the level of control at 0.044% AI (57.6%) was intermediate between the other treated groups. Therefore, none of the amitraz treatments provided the required 99% control necessary for use in the U.S. Cattle Fever Tick Eradication Program, and the estimated line derived from regression analysis showed that a concentration of ca. 0.2% AI amitraz would be needed to achieve 99% control of the resistant ticks.  相似文献   
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Biochar application has been received much attention because biochar can improve the fertilizer utilization efficiency of soil. However, the effect of biochar produced at different temperature on the nutrient retention and leaching remains poorly understood. In this study, we observed the nutrients leaching from a sandy loam soil amended with biochar produced at different temperature. The properties of biochars produced from wheat straw at four contrasting pyrolysis temperatures (250, 350, 450, and 550°C) showed that increasing pyrolysis temperature increased pH value and specific surface area but reduced the electrical conductivity and cation exchange capacity. With the temperature increased, the nitrogen loss was significant decreased (p > 0.05) from 109.6 mg to 53.3 mg in biochar amended soil. However, dissolved organic carbon (DOC), available P, Na and K were significant increased (p > 0.05). These results demonstrate that the pyrolytic temperature has a great influence on biochar properties, which in turn affect the leaching of the available nutrients.  相似文献   
49.
  • 1. Quantitative subtidal surveys of fishes, macro‐invertebrates and sessile organisms at 33 sites within the Lord Howe Island Marine Park revealed a rich fauna and flora, including 164 fishes, 40 mobile invertebrate taxa, 53 coral and other sessile invertebrate taxa, 32 algal taxa, and two seagrasses. The biota in this newly‐zoned marine park was overwhelmingly tropical when species lists were tabulated; however, species with distributions centred on temperate coasts of eastern Australia and New Zealand occurred in disproportionately high densities compared with the tropical species.
  • 2. Lord Howe Island reefs were generally in good condition. Virtually no bleached coral was observed (0.2% of the reef surface; 0.8% of total hard coral cover). Living scleractinian coral comprised the predominant group of organisms growing on reef surfaces, with 25.5% cover overall. Other major taxa observed were brown algae (18.8% cover) and red algae (16.9% cover).
  • 3. Three distinctive community types were identified within the marine park—coral reefs, macroalgal beds and an offshore/open coast community. The distribution of these community types was strongly related to wave exposure, as indicated by an extremely high correlation with the first principal coordinates axis for biotic data (R2=0.80).
  • 4. The close (<3 km) proximity of tropical coral and temperate macroalgal community types off Lord Howe Island is highly unusual, with localized patterns of nutrient enrichment suggested as the primary cause. The macroalgal community type is only known from a small area off the south‐western coast that is not protected from fishing. This community is considered highly susceptible to threats because of potential impacts of global warming and the possibility of expansion of sea urchin barrens. Coral bleaching and ocean acidification associated with global climate change also threaten the coral reef community, which includes relatively high numbers of endemic and near endemic fish species. Copyright © 2009 John Wiley & Sons, Ltd.
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50.
L-ascorbic acid (L-AA) concentration changes during the development of cv. Conference pears and the influence of postharvest handlings (gas condition, cooling rate, cooling duration) on L-AA breakdown were studied. L-AA concentration fluctuates in young fruits, remains stable during fruit maturation, and starts to decline 1 week before commercial harvest. The most rapid decrease in L-AA concentration was found during immediate controlled atmosphere. During short-term storage, only the gas condition was found to influence L-AA breakdown; no significant difference between gradually or immediately cooled pears was determined. Under air conditions, both cooling strategies did not differ from the L-AA breakdown in pears allowed to ripen on the tree up until 3 weeks after the optimal harvest date. During long-term storage, the cooling duration (1-3 weeks) had no effect whereas both O2 and CO2 had a significant effect on L-AA retention. After 7 months of storage, no difference was found in dehydroascorbic acid concentration; the L-AA and total L-AA concentrations, in contrast, were significantly lower in the 5% CO2 conditions.  相似文献   
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