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61.
Seven dogs with non-regenerative anaemia were diagnosed as having myelofibrosis on the basis of the presence of collagen and increased deposits of reticulin fibre in the haemopoietic spaces of bone marrow core biopsies. A scoring system was used to assess the cellularity of the marrow and the amounts of collagen, reticulin and haemosiderin present. These scores, together with the haematological findings, were compared with the dogs' responses to treatment and their outcome. Treatment consisted of blood transfusions, where required, and anabolic steroids and corticosteroids. Three dogs deteriorated and were euthanased within three months of diagnosis, but the other four recovered fully. There was no correlation between the collagen and reticulin scores, or the degree of anaemia and the outcome, but the four dogs which recovered all had a macrocytosis when first examined. There was no evidence of an underlying lymphoproliferative or myeloproliferative disease in any of the seven cases.  相似文献   
62.
The summary discusses techniques used to investigate mechanisms of resistance in the Colorado potato beetle (Leptinotarsa decemlineata) to several classes of pesticides.  相似文献   
63.
Between 1950 and 1989, marine fisheries catch in the open‐ocean and deep‐sea beyond 200 nautical miles from shore increased by a factor of more than 10. While high seas catches have since plateaued, fishing effort continues to increase linearly. The combination of increasing effort and illegal, unreported and unregulated (IUU) fishing has led to overfishing of target stocks and declines in biodiversity. To improve management, there have been numerous calls to increase monitoring, control and surveillance (MCS). However, MCS has been unevenly implemented, undermining efforts to sustainably use high seas and straddling stocks and protect associated species and ecosystems. The United Nations General Assembly is currently negotiating a new international treaty for the conservation and sustainable use of biodiversity beyond national jurisdiction (BBNJ). The new treaty offers an excellent opportunity to address discrepancies in how MCS is applied across regional fisheries management organizations (RFMOs). This paper identifies ways that automatic identification system (AIS) data can inform MCS on the high seas and thereby enhance conservation and management of biodiversity beyond national jurisdictions. AIS data can be used to (i) identify gaps in governance to underpin the importance of a holistic scope for the new agreement; (ii) monitor area‐based management tools; and (iii) increase the capacity of countries and RFMOs to manage via the technology transfer. Any new BBNJ treaty should emphasize MCS and the role of electronic monitoring including the use of AIS data, as well as government–industry–civil society partnerships to ensure critically important technology transfer and capacity building.  相似文献   
64.
Most laboratories make potassium (K) fertilizer recommendations based on field research calibrated with soil K from atomic absorption spectroscopy, flame emission spectroscopy, or inductively coupled plasma mass spectrometry. Information is needed to interpret readings from K+ meters on cotton. The objective was to compare soil and cotton plant sap potassium content from a Laqua Twin? K+ meter to results from standard tests. Aluminum sulfate solution was used with the meter to extract K from 10 soil samples from the North America Proficiency Testing program. A linear relationship (R2 = 0.86) was found between K measured with a K+ meter and K measured with 138 labs using ammonium acetate or Mehlich-3. Using a factor of 1.4754 to adjust readings, fertilizer recommendations with the K+ meter were similar to results from atomic absorption spectroscopy. A linear relationship was found between petiole K measured in the lab and petiole sap measured with the K+ meter.  相似文献   
65.
66.
Background: Glucocorticoids affect carbohydrate and lactate metabolism.
Hypothesis: Administration of prednisone to healthy dogs will result in clinically relevant hyperlactatemia.
Animals: Twelve healthy adult Beagle dogs.
Methods: Prospective, controlled experimental study. Twelve healthy adult Beagles were divided into 2 groups (3 of each sex per group). One group served as control. The other group received 2 treatments: low, 1 mg/kg prednisone PO q24h for 2 weeks; high, 4 mg/kg prednisone PO q24h for 2 weeks. A washout period of 6 weeks separated the treatments. Blood samples were drawn for whole blood lactate measurement on day (D) 0, D4, and D14 and measured in duplicate.
Results: Compared with the control group, low and high groups had significantly higher blood lactate concentrations at D4 and D14. There was no difference at D0. There was no effect of time within the control group. In the low and high groups, blood lactate concentration was increased at D4 and D14 versus D0. Blood lactate concentration was greater in the high group than the low group at D14 only.
Conclusions and Clinical Importance: Dogs treated with prednisone experience statistically significant increases in blood lactate concentrations, which can result in type B hyperlactatemia. In such cases, improving tissue perfusion, treatment for the commonest form of hyperlactatemia (type A) would be unnecessary.  相似文献   
67.
The purpose of this study was to determine the effectiveness of dry heat, steam, and microwave treatments in decreasing lipase activity, while retaining antioxidant activity, to stabilize whole wheat flour against lipid degradation during storage. Bran was heat‐treated in 230‐g batches using four levels (exposure times) for each of the three treatment methods. Lipase activity and antioxidant activity were quantified for all treatment combinations. None of the treatments significantly decreased antioxidant activity; the levels determined to be optimal, inasmuch as further heating did not significantly decrease lipase activity, were 25 min of dry heat, 60 sec of microwave (1000W), and 60 sec of steam. These treatments effectively decreased lipase activity by 74, 93, and 96%, respectively. Optimum treatments were evaluated for acceptance using a consumer sensory panel during a 12‐month storage period. No significant differences in acceptance were found between the control and any of the samples either at baseline or after storage. This suggests that whole wheat flour can be stabilized against lipolysis by utilizing the treatments described in this study without decreasing antioxidant activity, and that manufacturers may utilize these treatments without risking decreased consumer acceptance.  相似文献   
68.
Portable instruments have reduced on-site testing costs for soil pH and potassium in isolated locations. Acids could not be shipped to a remote Africa field laboratory. Bray-1 phosphorus (P) testing is difficult because hydrochloric (HCl) is required in the extraction solution and sulfuric acid (H2SO4) is used in color development stock solutions. Muriatic HCl acid and battery H2SO4 were available in a local stores. The objectives of this study were to evaluate the accuracy of P soil testing using diluted, non-reagent HCl for making modified Bray1-P extractant and non-reagent H2SO4 for color development. Experiment 1 was conducted with soil samples from fields using Sunnyside? and Klean Strip? HCl muriatic acids. Soil samples extracted with diluted reagent HCl were closely related to P results using diluted Klean Strip (R2 = 0.96) and Sunnyside (R2 = 0.84) HCl. In Experiment 2, two commercial brands of H2SO4 acid used to refill car battery cells were evaluated. Test results suggested that the battery H2SO4 acids are not suitable for making color development solution. In Experiment 3, a small battery powered spectrometer for P testing aquarium water was calibrated for soils. Samples from the Soil Science Society of America –North American Proficiency Testing program (NAPT) were tested with the meter and non-reagent HCl. Fiske-Subbarrow reducing agent and HCl were used in a variation procedure which does not require H2SO4 for color development. Eight of 10 samples tested proficient based on NAPT limits (2.5 x Median Absolute Deviation).  相似文献   
69.
There are various optical sensors in the market for precision nitrogen (N) management, which estimate leaf N status from chlorophyll content of leaves. However, readings may also be affected by the amounts of other nutrients in the plant leaves like potassium (K) and phosphorus (P), as well as sampling location within a plant or leaf. SPAD-502 and atLEAF optical sensors were used on Salvia ‘Vista Red’ plants grown with 0N-7.9P-0K, 41N-0P-0K, 0N-0P-31.6K, 0N-7.9P-0K + 41N-0P-0K, 0N-7.9P-0K + 0N-0P-31.6K, 41N-0P-0K + 0N-0P-31.6K, or 0N-7.9P-0K + 41N-0P-0K + 0N-0P-31.6K fertilizer plus a control. Both sensors were correlated with leaf N and each other. However, both sensor readings were affected by the presence or absence of P and K in the leaves, and thus these nutrients should be analyzed and reported along with leaf N values. Sensor readings were found to vary within a leaf and within leaf canopy location, so sampling needs to be consistent.  相似文献   
70.
Many oomycete and fungal plant pathogens are obligate biotrophs, which extract nutrients only from living plant tissue and cannot grow apart from their hosts. Although these pathogens cause substantial crop losses, little is known about the molecular basis or evolution of obligate biotrophy. Here, we report the genome sequence of the oomycete Hyaloperonospora arabidopsidis (Hpa), an obligate biotroph and natural pathogen of Arabidopsis thaliana. In comparison with genomes of related, hemibiotrophic Phytophthora species, the Hpa genome exhibits dramatic reductions in genes encoding (i) RXLR effectors and other secreted pathogenicity proteins, (ii) enzymes for assimilation of inorganic nitrogen and sulfur, and (iii) proteins associated with zoospore formation and motility. These attributes comprise a genomic signature of evolution toward obligate biotrophy.  相似文献   
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