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Herpesvirus anguillae (HVA) was detected during disease investigations of European eel, Anguilla anguilla L. at two stillwater fisheries in central England. These represent the first records of HVA from UK eels. Both mortalities were eel‐specific and took place during August 2009 and July 2010 at water temperatures between 17 and 19.4 °C. Pathological changes consistent with HVA infection included haemorrhaging in the fins, skin lesions and necrosis within the gills and liver. Transmission electron microscopy revealed active virion replication within the gill tissue. An initial assessment of risk is presented, indicating that HVA represents a high disease risk to UK eel stocks. However, further studies are required to establish the distribution of HVA before a reliable assessment of impact may be obtained. Until then, the detection of HVA holds important implications for eel conservation and management, in particular eel stocking activity.  相似文献   
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We report a catalytic system that produces olefin block copolymers with alternating semicrystalline and amorphous segments, achieved by varying the ratio of alpha-olefin to ethylene in the two types of blocks. The system uses a chain shuttling agent to transfer growing chains between two distinct catalysts with different monomer selectivities in a single polymerization reactor. The block copolymers simultaneously have high melting temperatures and low glass transition temperatures, and therefore they maintain excellent elastomeric properties at high temperatures. Furthermore, the materials are effectively produced in economically favorable, continuous polymerization processes.  相似文献   
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CASE DESCRIPTION: A 7-year-old Golden Retriever was examined because of anorexia, lethargy, vomiting, and gradual weight loss. CLINICAL FINDINGS: Splenomegaly, pancytopenia, high serum calcium concentration, and high alkaline phosphatase activity were detected. Magnetic resonance imaging revealed an enlarged mesenteric lymph node and increased signals from the bone marrow of the ilium and vertebral bodies. Histologic examination and immunophenotyping of biopsy specimens confirmed a stage V (b) T-cell malignant lymphoma. TREATMENT AND OUTCOME: Clinical remission was attained by use of 2 chemotherapy cycles, followed by an allogeneic hematopoietic cell transplant performed at 18 weeks after diagnosis. A donor was identified by molecular dog leukocyte antigen typing methods. The patient was conditioned with 2 fractions of 4 Gy total body irradiation delivered 3 hours apart at 7 cGy/min, followed by an IV infusion of recombinant canine granulocyte colony-stimulating factor mobilized leukapheresis product and postgrafting immunosuppression with cyclosporine. Chimerism analyses revealed full donor engraftment that has been maintained for at least 58 weeks after transplant. Remission has been confirmed by normal results of serum thymidine kinase assays and the absence of peripheral blood clonal T-cell receptor gene rearrangements. CLINICAL RELEVANCE: Systemic chemotherapy induces remissions; however, most dogs succumb to disease recurrence because of multidrug resistance. Outcome of allogeneic hematopoietic cell transplantation in dogs can be excellent because of improved donor-recipient selection by use of molecular dog leukocyte antigen typing, compared with early attempts, and better prevention of graft versus host disease, better supportive care, and substitution of peripheral blood mononuclear cells for bone marrow.  相似文献   
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Three soil nodules and an iron-pan have been analysed for the elements Al, Si, Ti, V, Mn, Fe, Co, Ni, Cu and Zn using an electron microprobe. From the surface analysis it appears that the nodules consist of two major concentration zones of enrichment, viz. Mn-rich, Fe-rich zones and a third zone low in Mn and Fe. The elements Co, Ni, Cu and Zn are enriched in the first zone, whereas vanadium is enriched in the second zone. Four concentration zones are distinguishable in the iron-pan, Ti-rich, Fe-rich, Ti and Fe-rich and a zone low in Ti and Fe. The metals Mn, Co, Ni, Cu and Zn are mainly enriched in the Ti/Fe-rich zone. The associations of the trace elements with the major components of the nodules and iron pan are discussed in terms of physico-chemical factors.  相似文献   
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The precision of instruments used in 3 collaborative studies conducted within the Food and Drug Administration over a 4-year period (1981, 1982, 1984) for water activity (aw) determinations according to the official AOAC method is evaluated. Calibration responses of the instruments were tested for linearity over the aw range from 0.75 to 0.97. Average absolute percent difference between predicted and assigned aw values for the linear model ranged from 0.3 to 0.7% for a fiber-dimensional hygrometer (Abbeon) and 3 electrical hygrometers (Beckman, Rotronics, and Weather Measure). The calibration responses for another electrical hygrometer (Hygrodynamics) were nonlinear. The fiber-dimensional hygrometer yielded mean aw values and precision estimates that did not differ significantly from those obtained with the electrical hygrometers for (NH4)2SO4slush, KNO3 slush, sweetened condensed milk, pancake syrup, and cheese spread. However, the mean aw value for a soy sauce was 0.838 for the electrical hygrometers compared with 0.911 for the fiber-dimensional hygrometer. The fiber-dimensional hygrometer was affected by a volatile component(s) in the soy sauce that caused an erroneously high aw value. Pooled estimates of reproducibility (Sx) in the 3 studies were 0.008 for the fiber-dimensional hygrometer and 0.010 for the electrical hygrometers; these values were not significantly different from those reported in the study that verified the current official AOAC method.  相似文献   
67.
A collaborative study was conducted in which 2 different sample preparation techniques were used to determine alkaline phosphatase in casein by the rapid colorimetric test. Seven collaborators tested 10 unknown casein products containing different amounts of residual phosphatase. Results indicated that the phosphatase contents of casein prepared by the 2 methods were not significantly different. The collaborators correctly analyzed 100% of the test samples that were ground and 98% of the test samples that were unground. The alternative rapid sample preparation method has been adopted official first action.  相似文献   
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