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951.
Sugar metabolism by Brucellae 总被引:3,自引:0,他引:3
The metabolic capabilities of the species of Brucella were originally of interest as a means of distinguishing them from each other and from other genera. Certain unusual characteristics, especially erythritol utilization, were studied in the hopes they would shed light on the pathogenicity. With the advent of modern genetic methods and genomic sequencing, it is now possible to get a good idea of the total capabilities of the organism and to do tests to confirm these deductions. Brucella appears to be a fairly normal member of the -proteobacteria, but with some differences. A few questions remain, such as whether Brucella uses the Entner–Doudoroff pathway. Some of the genes in carbohydrate utilization have been shown to be important in virulence. 相似文献
952.
Nelson L Reidesel E Ware WA Christensen WF 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2002,16(4):418-425
The purpose of this study was to assess the effects of systemic hypertension (SHT) on echocardiographic and radiographic cardiovascular variables in affected cats compared with healthy geriatric cats. Secondary objectives were to determine whether there were any relationships between these findings and age or systolic blood pressure (SBP). Fifteen healthy cats (>8 years of age with normal SBP) and 15 hypertensive cats (SBP > 180 mm Hg) were studied. Each cat was evaluated for standard echocardiographic parameters and 4 different aortic root dimensions. Seventeen variables were measured from right lateral and dorsoventral radiographic views. Left ventricle wall thickness was greater in the SHT group (5.1 +/- 0.9 mm) than in the healthy cats (4.2 +/- 0.5 mm). Left ventricular hypertrophy in the SHT cats often was not severe, and mean measures were considered normal. Some cats had asymmetrical septal hypertrophy (ASH) in the basilar portion of the septum as determined from the 2-dimensional view of the left ventricular outflow tract. ASH was greater in cats with SHT. Comparisons of the proximal ascending aorta indicated the presence of dilatation in the SHT cats, and comparison of the ascending aorta to the aortic annulus was helpful in differentiating between the 2 groups. The distal aortic root measurements and ratios evaluated by echocardiography were significantly different between the 2 groups of cats (P = .0001) and were significantly correlated with SBP (P = .0001) but not age (P > .3). 相似文献
953.
Myxobolus porofilus sp. n. is described infecting the visceral cavity of Prochilodus lineatus (Valenciennes, 1836) cultivated in S?o Paulo State, Brazil. The plasmodial form of the parasite is 3-5 mm in length and appeared compressed between the wall of the visceral cavity and the pyloric caecum, reposing on this organ. The spores are small (length 5.7 +/- 0.3 microm, width 4.8 +/- 0.2 microm; mean +/- SD) and round to elliptical in frontal view. The valve surfaces are smooth and have sutural folds. The polar capsules are ovoid, small (length 1.6 +/- 0.1 microm, width 1.1 +/- 0.1 microm) and equal in size. The polar filaments have three turns aligned perpendicularly to the longitudinal axis of the capsule. A conspicuous polar filament pore is arranged at the anterior end of the spore. The only reaction observed upon histological analysis was the presence of a capsule of connective tissue surrounding the plasmodia. This is the first report of a myxosporean parasite in the Prochilodontidae. 相似文献
954.
Spencer M Barber 《Veterinary Clinics of North America: Equine Practice》2005,21(1):191-215
The horse, a flight animal that is used extensively by man, frequently receives injuries to its neck or head that result mostly from its management and handling. Better facilities, training of the horse, and horsemanship skills of the handler could prevent many of these injuries. Because many body systems can be involved, with potentially major consequences regarding health, performance, and appearance, early recognition of trauma and competent treatment are crucial.Progress has been made in the treatment of some tracheal and esophageal injuries. Severe tracheal trauma and rupture of the esophagus still represent major challenges for the attending veterinarian, however. Lacerations of the head generally heal well, likely because of an abundant blood supply.Thorough yet conservative debridement is necessary, as is accurate reconstruction of the tissues to maintain normal function and an acceptable cosmetic appearance. Fractures of the facial bones can result in complications, such as sequestrum formation, sinusitis, nasolacrimal duct injury,facial deformity, and injury to or entrapment of the globe. An awareness of the treatment methods available can help to diminish the complication rate and to restore a normal or acceptable appearance. 相似文献
955.
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957.
Three insecticides, pyrethrins + piperonil butoxide (PBO), pymetrozine and triflumuron, were tested as potential alternatives
for controlling the Mediterranean fruit flyCeratitis capitata (Wiedemann) (Diptera: Tephritidae). The compounds were administered to adult flies in the laboratory by different uptake
methods at the recommended rates currently used in fruit crops in Spain. Pyrethrins + PBO (80 + 320 ppm a.i.) exhibited a
comparable knock-down effect to malathion (1,500 ppm a.i.) in the laboratory, irrespective of the method of application used.
After these results were obtained, the number of concentrations tested was increased to carry out a dose-response analysis.
Pymetrozine (300 ppm a.i.) and triflumuron (150 ppm a.i.) did not kill adults at the concentrations tested. However, pymetrozine
diminished the fecundity, especially when adults were fed the insecticide; egg hatch was decreased by 59.3% compared with
controls. Further experiments showed that increased period of ingestion and higher concentrations had a clear effect in reducing
both fecundity and fertility. The possible use of pyrethrins + PBO and pymetrozine to reduce populations ofC. capitata is discussed.
http://www.phytoparasitica.org posting July 22, 2006.
Corresponding author 相似文献
958.
Fresh fescue (Festuca arundinacea) was obtained from farms where toxicity was encountered in cattle grazing the fescue. The fescue was dried in a forced draft oven at 60 degrees C and then ground. The dry ground fescue was extracted with ether and then re-extracted with either 1% sodium bicarbonate (NaHCO3), sodium hydroxide or hydrochloric acid. The residual ether was evaporated and the residue resuspended in ethyl alcohol diluted with water 1% (control) and 1 mL of the above extracts of fescue were given daily to rats, via stomach tube, beginning the seventh day after breeding. Two of the seven rats given the 1% NaHCO3 fraction of the extract of fescue gave birth to live young. One of these litters contained only five pups, with one being stillborn. Three of the seven rats aborted, one gave birth to seven stillborn pups and one female died during birth. All females fed the 1% NaHCO3 and the other extracts of the fescue gave birth to normal litters. Rats fed the ether extract which was re-extracted with 1% NaHCO3, acidified and re-extracted with ether, dried and resuspended in 1% NaHCO3 produced similar reproductive problems as those rats given the ether extract of fescue which was re-extracted only once with 1% NaHCO3. Therefore, it appears that the toxic entity(s) of fescue can be extracted and that infertility/abortion/still-birth ratio of rats may be used as a bioassay. 相似文献
959.
960.
Late-onset cerebellar degeneration in a dog 总被引:1,自引:0,他引:1