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OBJECTIVE: To evaluate the effect of intratesticular administration of lidocaine on cardiovascular responses and cremaster muscle tension during castration of isoflurane-anesthetized stallions. ANIMALS: 28 healthy stallions (mean +/- SD age, 4.2 +/- 2.8 years) with no testicular abnormalities that were scheduled for castration. PROCEDURE: Each horse was given acepromazine (20 microg/kg, IM), romifidine (50 microg/kg, IV), and butorphanol (20 microg/kg, IV). Anesthesia was induced with ketamine (2.5 mg/kg, IV) and midazolam (50 microg/kg, IV) and maintained with isoflurane (1.7% end-tidal concentration). After 10 minutes at a stable anesthetic plane, a needle was placed in each testicle and either no fluid or 15 mL of 2% lidocaine was injected; 10 minutes after needle placement, surgery was commenced. Pulse rate and arterial blood pressures were measured invasively at intervals from 5 minutes prior to castration (baseline) until 5 minutes after the left spermatic cord was clamped. The surgeon subjectively scored the degree of cremaster muscle tension. In 2 horses, lidocaine labeled with radioactive carbon (C(14)) was used and testicular autoradiograms were obtained. RESULTS: Compared with baseline values, castration significantly increased blood pressure measurements; intratesticular injection of lidocaine decreased this blood pressure response and cremaster muscle tension. In 2 horses, autoradiography revealed diffuse distribution of lidocaine into the spermatic cord but poor distribution into the cremaster muscle. CONCLUSIONS AND CLINICAL RELEVANCE: In isoflurane-anesthetized stallions, intratesticular injection of lidocaine prior to castration appeared to decrease intraoperative blood pressure responses and cremaster muscle tension and may be a beneficial supplement to isoflurane anesthesia.  相似文献   
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Calcium-41 has been suggested as a new tool for radiometric dating in the range of 10(5) to 10(6) years. The concentration of cosmogenic calcium-41 in natural samples of terrestrial origin has now been determined by high-sensitivity accelerator mass spectrometry after pre-enrichment in calcium-41 with an isotope separator. Ratios of calcium-41 to total calcium between 2 x 10(-14) and 3 x 10(-15) were measured for samples of contemporary bovine bone and from limestone deposits. Some prospects for the use of calcium-41 for dating Middle and Late Pleistocene bone and for other geophysical applications are discussed.  相似文献   
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The fur industry and the entire fur cluster are in many ways an interesting and instructive example from which many lessons can be learned. Up to now, the international fur industry has not been thoroughly described or analyzed. A major reason is the rather limited availability of national and international statistics about the fur sector. This article analyzes the production and international trade in fur based on information from official statistics, trade associations, companies, scientific papers and reports, interviews with experts, etc.. Markets and market conditions play a very important role with regards to the fur sector, and the price of fur is volatile in the short and long run. A new world trade pattern and international specialization have emerged in recent years. The comparative advantages of the fur sector change along the fur value chain, while China's position on the global fur market has changed significantly.  相似文献   
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Methacrifos (22.5 g t?1) and the three protectant combinations chlorpyrifos-methyl (10 g t?1) plus bioresmethrin (1 g t?1), fenitrothion (12 g t?1) plus (1R)-phenothrin (2 g t?1) and pirimiphos-methyl (4 g t?1) plus carbaryl (8 g t?1) were each applied to grain that was stored in at least 15 silos. Grain temperature and levels of protectant were regularly monitored, and samples from 12 storages using each treatment were taken for laboratory assays against Rhyzopertha dominica and Tribolium castaneum. Grain condition did not deteriorate during storage. Grain remained free of insects in 60 of the 63 storages treated; partial failure in the other 3 storages was attributed to low or irregular levels of protectant. The mean and range of residue values of all protectants were recorded as a function of time and the mean observed values corresponded to predicted values. In laboratory bioassay, the order of effectiveness against T. castaneum was methacrifos > chlorpyrifos-methyl plus bioresmethrin > fenitrothion plus (1R)-phenothrin = pirimiphos-methyl plus carbaryl. The order of effectiveness against R. dominica was carbaryl plus pirimiphos-methyl = (1R)-phenothrin plus fenitrothion > methacrifos > bioresmethrin plus chlorpyrifos-methyl.  相似文献   
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A multilocus sequence analysis (MLSA) was carried out to delineate Aeromonas hydrophila from fish in Uganda. Five housekeeping genes including recA, gyrB, metG, gltA and pps; and the 16S rRNA gene were amplified and sequenced from a total of nine A. hydrophila isolates. The obtained sequences were edited, and consensus sequences generated for each gene locus. The housekeeping gene sequences were concatenated and phylogenetic analysis performed in MEGA version 7.0.2. Pairwise distances ranged from 0.000 to 0.118, highest within the gltA gene locus and lowest within the 16S rRNA gene. The average evolutionary diversity within isolates from the same source ranged between 0.002 and 0.037, and it was 0.033 between the different sources. Similar tree topologies were obtained from the different gene loci with recA, metG and gyrB being more consistent in discriminating isolates according to sources while the 16S rRNA gene had the lowest resolution. The concatenated tree had the highest discriminatory power. This study revealed that A. hydrophila strains infecting fish in Uganda are of diverse genotypes suggesting different sources of infection in a given outbreak. Efforts to minimize spread of the bacteria across sources should be emphasized to control infections of mixed genotypes.  相似文献   
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OBJECTIVE: To report treatment and wound healing after radical surgical mass excision in the equine buccal region. STUDY DESIGN: Clinical case reports. ANIMALS: An 11-year-old Warmblood gelding and a 9-year-old Norwegian Trotter gelding. METHODS: Large tumoral masses were removed from the buccal region by radical electrosurgery, creating large defects into the oral cavity. Wound ultimately healed by second intention. RESULTS: Buccal defects in both horses healed well by second intention without tumor recurrence. CONCLUSIONS: Locally invasive tumors involving the cheek region of the horse can be successfully treated by radical electroexcision alone, creating transmural defects up to 14 cm length x 8 cm height. CLINICAL RELEVANCE: Large transmural defects in the cheek region of the horse, formed by radical surgery can heal satisfactorily by second intention healing without undue discomfort to the patient or major complications.  相似文献   
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