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The purpose of this study was to evaluate the feasibility of proton magnetic resonance spectroscopy (1H MRS) to study the concentration of metabolites in the brain of dogs at 3.0 and 7.0 T. Four healthy male beagles were scanned using 3.0 T and 7.0 T human magnetic resonance imaging (MRI) units. The results obtained showed that all dogs had excellent quality spectra for a small (1 cm3) and large (8 cm3) voxel at 3.0 T, whereas only 2 dogs had high quality spectra at 7.0 T due to insufficient water suppression. 1H MRS at 3.0 T appears to be a reliable method to study metabolite concentrations in the canine brain. The development of more advanced water suppression techniques is necessary to improve the results at 7.0 T.  相似文献   
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The production of sorghum is hampered by the parasitic weed Striga asiatica L. Mulching is promoted as a component of the conservation agriculture systems in sub Saharan Africa. The objective of the study was to assess the effects of mulching and Striga infestation on sorghum chlorophyll content, Striga attachments, sorghum height, and yield. The 2?×?2?×?10 factorial experiment was replicated three times for two seasons. The pot experiment was laid out as a completely randomised design. The first factor was mulching at 0 and 3?tons/ha. The second factor was infestation at two levels: infested and uninfested while the third factor was sorghum varieties at 10 levels. Data collected was plant height, chlorophyll content, Striga counts and sorghum yield. Results indicated that mulching increased chlorophyll content in the second season and not first. Infestation reduced chlorophyll content in both seasons. For the second season, mulching increased chlorophyll content in all genotypes except Ruzangwaya, Mukadziusaende and SC Sila. The genotypes Mukadziusaende, Chiredhi and Hlubi were able to maintain height despite infestation by Striga. Generally yield was higher in uninfested pots across all varieties except Mukadziusaende for the first season. Sorghum arundinaceum was highly susceptible to Striga and hence cannot be a source of resistant traits for Sorghum bicolour breeding. Mulching in Striga infested plants increased plant height and chlorophyll content. Mulching tended to diminish the pathological effects of the Striga parasite in some varieties. Therefore, mulching negated the effect of Striga parasitism and resulted in yield maintenance in some genotypes and hence can be taken up by farmers in Striga infested areas as a beneficial cultural practice.  相似文献   
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Capture fisheries in the north‐east Atlantic account for approximately 10% of all fish consumed from capture fisheries globally. The literature shows that consumers show considerable interest in social sustainability of products in general and of fish specifically. This interest, however, has not yet been investigated for fish from the north‐east Atlantic. The first objective of this study, therefore, was to investigate whether consumers are interested in social sustainability issues of whitefish from the north‐east Atlantic by determining preferences for four social sustainability issues with distinct benefits in relation to a known reference point (i.e. approach to overfishing). The second objective of this study was to determine to what degree case‐specific and general psychographic consumer characteristics explain preferences for these issues. Choice modelling results from an online survey among 457 Dutch consumers show that consumers have the strongest preference for the environmental sustainability issue approach to overfishing. In addition, results on the social sustainability issues showed that consumers prefer fish welfare over product quality, worker safety and local employment, indicating that in this case, consumers place animal benefits over personal, worker and community benefits. The case‐specific psychographic characteristic concern contributed most to explaining preferences for the environmental sustainability issue, whereas the general psychographic characteristic personal relevance contributed most to explaining preferences for the social sustainability issues. This result is likely explained by the principal focus on MSC certification in markets for fish products, which caused consumers to form opinions (e.g. concern) on overfishing, but not on social sustainability.  相似文献   
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OBJECTIVE: To compare rectal (C(R) degrees ), coronary band (P(CB) degrees ) and ear base (P(E) degrees ) temperatures with pulmonary arterial temperature (C(PA) degrees ), and to investigate the relationship between core-peripheral temperature difference ([C - P]t degrees ) and cardiac output (Qt) in an acute ovine trauma model (PIL 60/9064). STUDY DESIGN: Observational study. ANIMALS: Thirteen mixed-breed male sheep, body mass (mean +/- SD) 45.50 +/- 4.21 kg, aged approximately 1 year. MATERIALS AND METHODS: Anaesthesia was induced with intravenous etomidate 0.5 mg kg(-1) and midazolam 0.5 mg kg(-1) and following endotracheal intubation maintained with halothane in a 2:1 N(2)O:O(2) mixture. The lungs were mechanically ventilated to maintain normocapnia. Core temperature was measured using a pulmonary arterial thermistor. Rectal temperature and peripheral temperatures at the thoracic limb coronary band and ear base were recorded using thermistor probes with a multi-channel recorder. Cardiac output was measured by continuous thermodilution. Recordings were taken hourly over a 24-hour period. After baseline data collection, hypovolaemia was induced by haemorrhage from bilateral femoral fractures. The development of hypovolaemic shock was confirmed by falling Qt, central venous pressure, mean arterial pressure and urine output. Resuscitation was attempted using intravenous fluids, inotropes and vasoconstrictors. Nine sheep received lumbosacral extradural bupivacaine. RESULTS: The rectal temperature correlated closely with pulmonary arterial temperature in all sheep (r(c) = 0.924). There was no consistent statistically significant relationship between Qt and [C - P]t degrees . CONCLUSIONS AND CLINICAL RELEVANCE: Rectal temperature accurately reflected core temperature in anaesthetized sheep but [C - P]t degrees was unrelated to Qt, under the conditions described in this study.  相似文献   
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A 20-month-old castrated male Labrador Retriever with a 3-month history of anorexia, weight loss, and vomiting was evaluated. Plasma biochemical abnormalities included marked hyperglobulinemia and hypercalcemia. Serum levels of parathyroid hormone, parathyroid hormone-related protein, 25-hydroxyvitamin D, and 1,25-dihydroxyvitamin D were either low or within reference intervals. Gastric wall thickening and abdominal lymphadenomegaly were observed with abdominal ultrasonography. Cytologic evaluation of a sample obtained via fine-needle aspiration of the gastric wall revealed pyogranulomatous inflammation and numerous poorly stained hyphae. Partial gastrectomy was performed, and a diagnosis of gastric pythiosis was made by immunohistochemical staining of infected gastric tissue, as well as by immunoblot serology. This case demonstrates that diagnostic samples for cytologic evaluation can be obtained by fine-needle aspiration of Pythium insidiosum-infected tissues and that a presumptive diagnosis can be made by examination of a Romanowsky-stained smear. Furthermore, pythiosis should be considered as a differential diagnosis for hypercalcemia, especially in young dogs with inflammatory lesions that have a granulomatous component. The mechanism for the hypercalcemia in this dog was not determined; however, calcium concentrations normalized after surgical resection of the gastric lesion.  相似文献   
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ObjectiveTo evaluate the post‐tetanic count (PTC) for predicting the return of reversible neuromuscular blockade at the n. facialis–m. nasolabialis (nF–mNL) and n. ulnaris–mm. carpi flexorii (nU–mCF) nerve‐muscle units (NMUs) during profound vecuronium neuromuscular blockade in halothane‐anaesthetized dogs.Study designRandomized, prospective, experimental study.AnimalsTwenty‐five dogs (seven male 18 female) undergoing surgery; mean age: 4.8 years; mean body weight 22 kg.MethodsThirty minutes after acepromazine (0.05 mg kg?1) and morphine (0.5 mg kg?1) pre‐medication, anaesthesia was induced with intravenous (IV) thiopental and maintained with halothane, N2O and O2. The lungs were mechanically ventilated and end‐tidal halothane concentration (Fe′HAL) maintained at 1.04%. Neuromuscular transmission was monitored using the train‐of‐four count (TOFC) at one nF–mNL and both nU–mCF units. Vecuronium (50 µg kg?1 IV) was injected after 15 minutes constant Fe′HAL. When the first twitch (T1) at both nU–mCF units had disappeared (t = 0) one (randomly allocated) ulnar nerve was stimulated every 5 minutes using PTC; TOF stimulation continued at the other sites. The PTC was plotted against the interval between recording time and T1's reappearance at the other NMUs.ResultsAt t = 0, the mean PTC in the contralateral nU–mCF unit was 18 (range 0–20). Mean PTC was a minimum at t = 5, rising to the maximum (20) at 25 minutes. Six dogs were vecuronium‐resistant as monitored by PTC. Excluding data from these revealed a strong negative relationship between ulnar PTC and the time taken for T1's return at the facial (r = ?0.7018; p < 0.00001) and contralateral ulnar (r = ?0.8409; p < 0.00001) NMUs.Conclusion and clinical relevancePost‐tetanic count monitoring beginning >5 minutes after the TOFC at nU–mCF = 0 provided a reliable estimate of T1's return at ulnar and facial NMUs.  相似文献   
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