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Fish medicine has common diagnostic and clinical procedures that are essential for disease diagnosis and patient management. With a few modifications for handling of the fish patient, these resemble procedures performed in most veterinary hospitals and clinics in our other companion species. The predictive value of these diagnostic methods is improving with the ever-increasing number of publications in fish medicine. Training in aquatic clinical procedures is offered at most large continuing education conferences and as specialty courses. These basic procedures are the important first steps toward improving the health of our aquatic companion animals.  相似文献   
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The aim of this study was to induce embryogenic callus from various cultivars of cotton in tissue culture, so that a stable and efficient regeneration system could be developed to produce new cotton varieties for cultivation in Xinjiang. The explant materials were hypocotyls of the main cotton cultivars grown in Xinjiang, i. e. Xinhai 25, Xinhai 16, Xinluzao 39, and Xinluzao 42. We tested the effects of different combinations of two hormones (kinetin, KT; 2,4-dichlorophenoxyacetic acid, 2,4-D) on induction of callus from these explants. Calli were produced by the explants under four different combinations of hormones in the media. The optimal hormone combination to induce callus from Gossypium hirsutum explants was 0.1 mg·L-1 KT + 0.05 mg·L-1 2,4-D, while that to induce callus from Gossypium barbadense explants was 0.1 mg·L-1 KT + 0.1 mg·L-1 2,4-D. Hormone-free medium and medium containing double to the normal concentration of KNO3 promoted the emergence of embryogenic callus. Filter paper placed under the medium promoted somatic embryo growth and regeneration of the root system. The differentiation and embryogenesis processes occurred more rapidly in G. hirsutum explants than those in G. barbadense explants. Using this protocol, normal plantlets of these cotton cultivars with strong roots were produced within 10 to 12 months. These methods could be used to increase the number of cotton genotypes that can be regenerated in tissue culture.  相似文献   
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Very high energy gamma-rays probe the long-standing mystery of the origin of cosmic rays. Produced in the interactions of accelerated particles in astrophysical objects, they can be used to image cosmic particle accelerators. A first sensitive survey of the inner part of the Milky Way with the High Energy Stereoscopic System (HESS) reveals a population of eight previously unknown firmly detected sources of very high energy gamma-rays. At least two have no known radio or x-ray counterpart and may be representative of a new class of "dark" nucleonic cosmic ray sources.  相似文献   
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The objective of this study was to determine whether models developed from infrared spectroscopy could be used to estimate organic carbon (C) content, total nitrogen (N) content and the C:N ratio in the particulate organic matter (POM) and particle size fraction samples of Brookston clay loam. The POM model was developed with 165 samples, and the particle size fraction models were developed using 221 samples. Soil organic C and total N contents in the POM and particle size fractions (sand, 2000–53 µm; silt, 53–2 µm; clay, <2 µm) were determined by using dry combustion techniques. The bulk soil samples were scanned from 4000 to 400 cm?1 for mid‐infrared (MIR) spectra and from 8000 to 4000 cm?1 for near‐infrared (NIR) spectra. Partial least squares regression (PLSR) analysis and the ‘leave‐one‐out' cross‐validation procedure were used for the model calibration and validation. Organic C and N content and C:N ratio in the POM were well predicted with both MIR‐ and NIR‐PLSR models ( = 0.84–0.92; = 0.78–0.87). The predictions of organic C content in soil particle size fractions were also very good for the model calibration ( = 0.84–0.94 for MIR and = 0.86–0.92 for NIR) and model validation ( = 0.79–0.94 for MIR and = 0.84–0.91 for NIR). The prediction of MIR‐ and NIR‐PLSR models for the N content and the C:N ratio in the sand and clay fractions was also satisfactory ( = 0.73–0.88; = 0.67–0.85). However, the predictions for the N content and C:N ratio in the silt fraction were poor ( = 0.23–0.55; = 0.20–0.40). The results indicate that both MIR and NIR methods can be used as alternative methods for estimating organic C and total N in the POM and particle size fractions of soil samples. However, the NIR model is better for estimating organic C and N in POM and sand fractions than the MIR model, whereas the MIR model is superior to the NIR model for estimating organic C in silt and clay fractions and N in clay fractions.  相似文献   
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Three dogs were presented with a history of oral administration of a topical endectocide containing imidacloprid and moxidectin. They were diagnosed with imidacloprid and moxidectin intoxication, having ingested doses ranging from 7.5 to 1.4 mg/kg of imidacloprid and 1.9 to 2.8 mg/kg of moxidectin. The three dogs were affected to different degrees of severity, but all displayed signs of ataxia, generalised muscle tremors, paresis, hypersalivation and disorientation. Temporary blindness occurred in two cases. The three dogs were tested for the presence of the multi-drug resistance 1 gene deletion, which can cause an increased sensitivity to the toxic effects of moxidectin, and were found to be negative. Treatment included gastrointestinal decontamination, intravenous fluid therapy and benzodiazepines to control muscle tremors. All three dogs made a complete recovery within 48 h of ingestion.  相似文献   
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Objective   To assess the incidence of lymphoma and wasting-related deaths in the National Baboon Colony of Australia and relate it to the presence of simian T-cell lymphotrophic virus 1 (STLV-1) infection.
Design and procedure   The records of all animals that had died since establishment of the National Baboon Colony in Australia were reviewed retrospectively. The clinical signs and histopathological findings were recorded and assessed to determine the involvement of lymphoma in the deaths. The presence of STLV-1 was recorded if known and correlated with the STLV-1 status of the colony.
Results   Of the deaths from disease or illness, 53% were diagnosed as or suspected to be lymphoma, occurring in mature animals with no sex predisposition. The most common presentation was rapidly occurring generalised lymphadenomegaly.
Conclusions   This study has described a relatively high prevalence of lymphoma in a colony of captive-bred baboons, and it is evident that STLV-1 may play a role in the disease. Management practices in baboon colonies need to take into account the possible presence of STLV-1 and aim to reduce the transmission of the virus by preventing sexual contact between positive and negative animals. Lymphoma needs to be considered as one of the more common causes of wasting and death.  相似文献   
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