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Two Thoroughbred horses were presented with various clinical signs which included sweating, agitation, muscle twitching and synchronous diaphragmatic flutter. These signs were associated with profound hypocalcaemia. A diagnosis of primary hypoparathyroidism was made on the basis of low serum ionised calcium concentration, hyperphosphataemia and markedly reduced serum immunoreactive parathyroid hormone concentrations in the presence of normal renal function. Treatment with a combination of intravenous calcium and subsequently oral calcium, magnesium and a vitamin D analogue (dihydrotachysterol) for up to 65 days resulted in complete remission of clinical signs. Horse 1 was euthanased 12 months after the initial recognition of signs. Results of necropsy were unremarkable apart from an absence of detectable parathyroid tissue. Horse 2 returned to athletic activities while receiving only maintenance doses of oral calcium carbonate.  相似文献   
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OBJECTIVE: To examine the effect of acute haemorrhage on the QRS amplitude of the canine lead II surface electrocardiograph (ECG). DESIGN: Ten adult racing Greyhounds were tranquilised, anaesthetised, positioned in right lateral recumbency and connected to recording electrodes of an ECG unit. Baseline six-lead ECG traces were recorded, and further traces were obtained after one unit (460 mL) of blood, and then a second unit, were collected from the femoral artery. RESULTS: There was a consistent and progressive reduction in amplitude of the QRS complex in all leads during acute haemorrhage. QRS amplitude in lead II after removal of two units of blood averaged 74% of the baseline voltage, with individual values of 61 to 91% (P < 0.0001). There were even greater reductions in QRS amplitudes in lead aVL during haemorrhage. In three additional dogs, reductions in QRS voltages were shown to be accompanied by reductions in end-diastolic left ventricular internal dimensions measured echocardiographically. Furthermore, the effects of haemorrhage on the QRS amplitude and echocardiographic measurements were reversed when circulating blood volume was restored by re-infusion of blood removed previously. CONCLUSION: Acute haemorrhage corresponding to an approximately one-third reduction in blood volume caused a substantial reduction in QRS voltage of the surface ECG. It is postulated that this resulted from diminished ventricular distension as a consequence of reduced venous return. A similar mechanism may account for the small-amplitude ECG complexes associated with pericardial effusion, severe dehydration and hypovolaemia.  相似文献   
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This paper assesses the extent to which threshold firms have emerged within British Columbia's wood processing industries. Threshold firms comprise an innovative business segment and are growth oriented, larger than most small firms but not giant, locally owned, international in scope at least with respect to exporting, reliant on skilled, well paid employees, and that have developed knowledge‐based product market advantages. The analysis draws on an extended case study survey of 14 firms located in the lower mainland and Okanagan regions of British Columbia, and selected for their potential as threshold firms. The analysis examines six characteristics associated with threshold firms: size and ownership, internationalization, wood supply, labor relations, innovative design and collaboration, and local embeddedness. These firms reveal attributes of threshold firms, and the paper concludes by suggesting that an innovative forest policy for British Columbia could usefully focus on this type of firm.  相似文献   
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Background: Hematologic analysis is an important tool in evaluating the general health status of free‐ranging manatees and in the diagnosis and monitoring of rehabilitating animals. Objectives: The purpose of this study was to evaluate diagnostically important hematologic analytes in healthy manatees (Trichechus manatus) and to assess variations with respect to location (free ranging vs captive), age class (small calves, large calves, subadults, and adults), and gender. Methods: Blood was collected from 55 free‐ranging and 63 captive healthy manatees. Most analytes were measured using a CELL‐DYN 3500R; automated reticulocytes were measured with an ADVIA 120. Standard manual methods were used for differential leukocyte counts, reticulocyte and Heinz body counts, and plasma protein and fibrinogen concentrations. Results: Rouleaux, slight polychromasia, stomatocytosis, and low numbers of schistocytes and nucleated RBCs (NRBCs) were seen often in stained blood films. Manual reticulocyte counts were higher than automated reticulocyte counts. Heinz bodies were present in erythrocytes of most manatees. Compared with free‐ranging manatees, captive animals had slightly lower MCV, MCH, and eosinophil counts and slightly higher heterophil and NRBC counts, and fibrinogen concentration. Total leukocyte, heterophil, and monocyte counts tended to be lower in adults than in younger animals. Small calves tended to have higher reticulocyte counts and NRBC counts than older animals. Conclusions: Hematologic findings were generally similar between captive and free‐ranging manatees. Higher manual reticulocyte counts suggest the ADVIA detects only reticulocytes containing large amounts of RNA. Higher reticulocyte and NRBC counts in young calves probably reflect an increased rate of erythropoiesis compared with older animals.  相似文献   
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The Atmosphere Structure Instrument on the Galileo probe detected wavelike temperature fluctuations superimposed on a 700-kelvin temperature increase in Jupiter's thermosphere. These fluctuations are consistent with gravity waves that are viscously damped in the thermosphere. Moreover, heating by these waves can explain the temperature increase measured by the probe. This heating mechanism should be applicable to the thermospheres of the other giant planets and may help solve the long-standing question of the source of their high thermospheric temperatures.  相似文献   
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The contemporary process of financialization has been a major driver of the remarkable changes witnessed in global food and agricultural markets over the past decade, contributing to the rise and subsequent volatility of food and agricultural commodity prices since 2006. In the wake of these developments it has become clear that the turmoil has intensified the relationship between agriculture and finance in ways that have profound and enduring implications for the sector, and the people whose lives and livelihoods depend upon it. This symposium brings together four original research articles that contemplate the contemporary relationship between the agrifood and financial sectors. They examine a variety of overlapping themes, including the creation of financial assets from farmland and agricultural commodities, the activities of different types of investors in these assets in specific geographic contexts, and the challenges of governing this activity at the global scale. These articles show that the period of market volatility that began a decade ago re-invigorated investor interest in financial products linked to agriculture and farming, and inspired the packaging of new forms of financial assets in ways that have affected politics and practice on the ground, and are likely to leave a lasting legacy.  相似文献   
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