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101.
Iron oxides in two Oxisols from the Brazilian coastal plain   总被引:1,自引:0,他引:1  
Two Oxisols from the B2 horizon at similar locations 2 km apart on the Brazilian coastal plain with a udic, isohyperthermic regime were practically identical in chemical composition but differed markedly in colour; one was a dark reddish brown, the other a pale ochre. Mossbauer spectra at 295 K, 80 K and 4.2 K indicated a clear difference in iron oxide mineralogy. Iron was present as aluminous hematite and goethite, with Al substitutions of approximately 20% in the two phases. However, the relative proportion of iron present in hematite and goethite was 45:55 in the first sample and 12:88 in the second. Possible reasons for these differences are discussed.  相似文献   
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农业产业集群是推动农村经济发展的重要产业组织形式。现以新疆为研究对象,从新疆农业产业集群的发展优势和现状出发,结合区位商进行分析,发现当前新疆农业产业集群主要面临产业链条短、市场需求反应慢、支持服务体系不健全等问题,最后从产业链、科技投入、市场需求和网络体系等角度提出新疆农业产业集群发展的对策。  相似文献   
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108.
1. Sampling carcasses after plucking or after the post‐evisceration spray‐wash showed that 10 or 20 ppm available chlorine in the processing‐plant water supply caused little reduction in carcass contamination.

2. When 20 ppm chlorine was used in the water supply to parts of the processing‐plant other than the mechanical immersion chilling system, counts of faecal and spoilage bacteria from carcasses were reduced approximately 10‐fold after passage through the chilling system; bacterial numbers were correspondingly decreased in the chiller water due to a carry‐over of chlorine from the final spray‐washer.

3. Artificial contamination of carcasses with a readily identifiable strain of Escherichia coli confirmed the occurrence of cross‐contamination during plucking and evisceration; in‐plant chlorination reduced neither the proportion of carcasses contaminated nor the numbers of organisms transferred at these stages.

4. In most cases the chlorine‐resistance of poultry spoilage pseudo‐monads was greater than that of E. coli; hence in‐plant chlorination is to be recommended for processing‐plant water supplies which carry such spoilage organisms.  相似文献   

109.
Feline leukemia virus is an oncogenic retrovirus that can result in a wide variety of neoplastic and non-neoplastic diseases, including immunosuppression. Diagnosis of FeLV infection can be achieved by several methods, including virus isolation; IFA assay of a peripheral blood smear; and detection of a viral protein (called p27) by ELISA testing of whole blood, plasma, serum, saliva, or tears. Commercially available ELISA kits have revolutionized FeLV testing and have become very popular as "in-house" procedures. This article discusses the interpretation of ELISA results and compares them with IFA assay findings. Feline immunodeficiency virus is a lentivirus that causes immunosuppression, but not neoplasia, in cats. It originally was called feline T-lymphotropic lentivirus. Differentiating FIV infection from the immunosuppressive type of FeLV infection requires virus isolation or serology. The most rapid method for diagnosis of FIV infection is ELISA testing for antiviral antibody.  相似文献   
110.

Aim

A prospective, observational study to determine the prevalence of post‐exercise conditions at Australian Greyhound race meetings and to assess association with race performance and other environmental, race‐ and dog‐related factors was undertaken.

Methods

A total of 4020 starters were observed (2813 Greyhounds, 1009 trainers, 536 races, 52 race meets, 48 race dates and 11 race tracks) following a race. The presence of diaphragmatic flutter (DF), ataxia, seizure, collapse or sudden death was recorded. Risk factors were screened by univariable logistic regression prior to multivariable backward stepwise model building.

Results

In this study, 962 starters (n = 768 dogs) had DF (23.9%), 16 starters were ataxic (0.4%) and there were no observed cases of collapse, seizure or sudden death. Race track location, increasing race distance, race grade based on increasing 1st place prize value, lower (earlier) race number at the meeting, age, a previous observation of DF at the last start, females, colour (white) and better finishing position were all associated with an increased risk of a Greyhound being observed with DF. However, when logistic regression assessing the random effect of dog was performed, the presence of previous DF was not significant. In this cohort, DF was common following strenuous exercise in Greyhounds and on its own does not appear to result in reduced performance or distress to the animal.

Conclusion

The incidence of ataxia was low and collapse, seizure and sudden death were not observed. However, even though uncommon, ataxia has welfare concerns for racing Greyhounds that warrants further investigation.  相似文献   
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