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51.
G M Baxter W P Hay B A Selcer 《Journal of the American Veterinary Medical Association》1991,198(4):669-671
Osteochondritis dissecans of the proximal aspect of the medial trochlear ridge of the talus was found to be causing lameness and tarsocrural joint effusion in a male Limousin calf. Arthroscopy via a dorsolateral approach was unsuccessful in revealing the lesion in this calf. A caudomedial arthrotomy or medial malleolar osteotomy, which can be used to gain access to lesions of the medial trochlear ridge in dogs, was not attempted. The lameness gradually worsened, and the calf was slaughtered. 相似文献
52.
The genome sequence of Drosophila melanogaster 总被引:2,自引:0,他引:2
Adams MD Celniker SE Holt RA Evans CA Gocayne JD Amanatides PG Scherer SE Li PW Hoskins RA Galle RF George RA Lewis SE Richards S Ashburner M Henderson SN Sutton GG Wortman JR Yandell MD Zhang Q Chen LX Brandon RC Rogers YH Blazej RG Champe M Pfeiffer BD Wan KH Doyle C Baxter EG Helt G Nelson CR Gabor GL Abril JF Agbayani A An HJ Andrews-Pfannkoch C Baldwin D Ballew RM Basu A Baxendale J Bayraktaroglu L Beasley EM Beeson KY Benos PV Berman BP Bhandari D Bolshakov S Borkova D Botchan MR Bouck J 《Science (New York, N.Y.)》2000,287(5461):2185-2195
The fly Drosophila melanogaster is one of the most intensively studied organisms in biology and serves as a model system for the investigation of many developmental and cellular processes common to higher eukaryotes, including humans. We have determined the nucleotide sequence of nearly all of the approximately 120-megabase euchromatic portion of the Drosophila genome using a whole-genome shotgun sequencing strategy supported by extensive clone-based sequence and a high-quality bacterial artificial chromosome physical map. Efforts are under way to close the remaining gaps; however, the sequence is of sufficient accuracy and contiguity to be declared substantially complete and to support an initial analysis of genome structure and preliminary gene annotation and interpretation. The genome encodes approximately 13,600 genes, somewhat fewer than the smaller Caenorhabditis elegans genome, but with comparable functional diversity. 相似文献
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The isolated toad brain accumulates L-glutamate against strong concentration gradients until a tissue-to-medium concentration ratio of about 3000 : 1 is attained. The accumulated glutamate does not equilibrate with most of the endogenous tissue glutamate but is converted rapidly to glutamine and released into the medium. This mechanism may be involved in the preservation of low extracellular levels of cerebral glutamate. 相似文献
57.
Competition for attachment of aquaculture candidate probiotic and pathogenic bacteria on fish intestinal mucus 总被引:7,自引:0,他引:7
Probiotics for aquaculture are generally only selected by their ability to produce antimicrobial metabolites; however, attachment to intestinal mucus is important in order to remain within the gut of its host. Five candidate probiotics (AP1-AP5), isolated from the clownfish, Amphiprion percula (Lacepéde), were examined for their ability to attach to fish intestinal mucus and compete with two pathogens, Aeromonas hydrophila and Vibrio alginolyticus. Two different radioactive isotopes were used to quantify competition between pathogens and probionts. Attachment of the pathogens was enhanced by the presence of the candidate probiotics. However, the addition of the candidate probiotics after the pathogens resulted in reduced pathogen attachment. Only AP5 caused lower attachment success of V. alginolyticus when added before the pathogen. When AP5 was added first, the average attachment change was 41% compared with 72% when added after V. alginolyticus, suggesting that the probiotic is displaced but that enhanced attachment of the pathogen does not occur. Conversely, when V. alginolyticus was added first, followed by AP5, attachment change was 37% while AP5 had 92% attachment change when added second. This implies that the pathogen was displaced by the candidate probiotic and therefore it appeared that, based on the ability of probiont AP5 to attach to mucus, the growth of the pathogen in the digestive tract might be suppressed by the candidate probiont's presence. 相似文献
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Ilia Rodushkin Emma Engstr?m Dieke S?rlin Douglas Baxter Birger H?rnfeldt Erik Nyholm Frauke Ecke 《Water, air, and soil pollution》2011,217(1-4):603-610
Chitosan is a biodegradable cationic polymer that may be a potential substitute for aluminum salts in water treatment systems. In our study, we compared the coagulation performances of chitosan with those of coagulant mixtures of chitosan and aluminum sulfate and chitosan and poly-aluminum chloride, respectively. The coagulation efficiency was evaluated in terms of coagulant dosage, solution pH, settling velocity of flocs, floc diameter, and water turbidity. The optimum dosages for acid-soluble and water-soluble chitosan required for removal of a bentonite suspension (100 NTU) were only 1.25 and 1.50 mg/l, respectively, at a respective efficiency of 99.2% and 95.8%. The optimal dosage range for water-soluble chitosan was broader than that for acid-soluble chitosan. The coagulation of bentonite decreased with increasing pH when acid-soluble chitosan was the coagulant. In contrast, the coagulation efficiency of bentonite was not affected at pH 5?C9 when water-soluble chitosan was the coagulant. The mixing of chitosan with alum or PAC in a 1:1 mass ratio significantly improved the coagulation process in terms of preventing the occurrence of re-stabilization. The highest floc settling velocity occurred at a dosage of 5?C6 mg/l of the coagulant mixtures, which was also the highest coagulation efficiency. Given the relatively high cost of chitosan and the good coagulation performance of the coagulant mixtures, we suggest that a 1:1 mass ratio of chitosan mixed with alum or PAC may be an alternative method to the use of pure chitosan in water treatment systems. 相似文献
60.
Equine laminitis caused by distal displacement of the distal phalanx: 12 cases (1976-1985) 总被引:1,自引:0,他引:1
G M Baxter 《Journal of the American Veterinary Medical Association》1986,189(3):326-329
Clinical data from 12 cases of equine laminitis characterized by distal displacement of the distal phalanx (P3) were reviewed. Clinical features of horses that survived the syndrome were compared with the nonsurvivors to obtain prognostic indicators. Animals affected included 8 Quarter Horses, 2 Welsh ponies, 1 Thoroughbred, and 1 Arabian. Eight of the animals were females (67%), 2 were stallions, and 2 were geldings. The mean age of affected animals was 8.6 years (2 to 14 years), and the mean body weight was 442 kg. The survivors weighed less than the nonsurvivors (384 kg vs 473 kg, respectively), suggesting that body weight may be of prognostic value for horses affected with distal displacement of P3. Ten of the 12 animals (83%) were admitted because of a disorder other than laminitis, but subsequently developed laminitis during the treatment period. All affected animals had clinical evidence of endotoxemia and/or sepsis before the onset of laminitis. Cavitation or depression of the dorsal coronary band was detected in all animals and was the most reliable clinical indicator of distal displacement of P3. Five horses had fluid (blood or serum) ooze from their coronary bands and 2 of these sloughed one or more of their hooves. Necropsy findings of the 8 horses that were euthanatized included severe hemorrhagic, congested laminae and complete detachment of P3 from the hoof wall. Histologic examination of affected laminae revealed vascular thrombosis and multifocal areas of hemorrhage and necrosis. Radiography failed to reveal distal displacement of P3 in 8 animals, but the remaining 4 animals had an accentuation of the dorsal proximal hoof wall and cavitation of the coronary band visible on lateral radiographs. 相似文献