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141.
OBJECTIVE: To identify factors affecting radial alignment after oblique corrective osteotomy stabilized with a type II external fixator and to evaluate the results of this treatment for antebrachial growth deformities. STUDY DESIGN: Retrospective study SAMPLE POPULATION: Twenty-eight dogs with unilateral antebrachial growth deformities treated with acute corrective osteotomy stabilized with a type II external fixator. METHODS: Medical records and preoperative and postoperative radiographs of the affected and contralateral limb were reviewed. Cause of deformity, age, weight, and gender were recorded. Radial length, varus/valgus angulation, and cranial/caudal angulation were measured from radiographs of the treated and contralateral limbs. Preoperative and postoperative angulation and length discrepancy were compared between affected and contralateral limbs. RESULTS: Correction of varus/valgus angle discrepancy was achieved by using acute corrective osteotomy stabilized with type II external skeletal fixation. No significant change was noted for correction of cranial/caudal angle discrepancy or length discrepancy between the affected and control limb. CLINICAL RELEVANCE: Varus/valgus angle deformities can be treated successfully with type III external fixation after oblique corrective osteotomy. Patients with significant length or cranial/caudal angle discrepancies or both that negatively impact function may require the use of hinged circular fixators or other dynamic techniques to achieve adequate correction. 相似文献
142.
Johnson EH Windsor JJ Muirhead DE King GJ Al-Busaidy R 《Veterinary research communications》2000,24(1):63-67
Veterinary Research Communications - 相似文献
143.
Paracox anticoccidial vaccine was administered to a 7-day-old flock of commercial broiler breeder stock subsequently reared to point-of-lay in the same house. For comparison, three subgroups of another flock of broiler breeders were also vaccinated with Paracox at 7 days of age, reared to 42 days and then transferred to new litter on another farm until point-of-lay. The first subgroup received no further treatment, but the second and third each received a second vaccination with Paracox, either immediately after transfer to the new litter or 42 days after transfer. Using an Eimeria necatrix model, protective immunity was demonstrated by virulent challenge of samples of birds from all groups by the age of 37–40 days (30–33 days after the first vaccination), and was maintained to at least 122–125 days of age, whether the birds remained on the same litter or were transferred to another farm, and whether they received one or two anticoccidial vaccinations. Therefore, there is no disadvantage in transferring birds onto new litter 35 days after a single Paracox vaccination, nor is there any advantage in giving a second vaccination after such a transfer. Vaccinated birds seeded the new litter with oocysts, despite being clinically immune to coccidiosis. A supplementary laboratory experiment showed that birds vaccinated at 8 days of age passed almost no oocysts after a second vaccination at 43 days of age. This indicated that they were not only protected against clinical coccidiosis, but were almost solidly immune to a homologous infection 5 weeks after a single vaccination. Nevertheless, oocysts appeared in the litter of all four groups of commercial breeders throughout the trial, showing that wild-type heterologous infections occurred whether the birds were transferred to new litter or not, but these did not overwhelm the acquired protective immunity and cause clinical coccidiosis. 相似文献
144.
Estimation of sensitivity and specificity of diagnostic tests and disease prevalence when the true disease state is unknown 总被引:1,自引:0,他引:1
The performance of a new diagnostic test is frequently evaluated by comparison to a perfect reference test (i.e. a gold standard). In many instances, however, a reference test is less than perfect. In this paper, we review methods for estimation of the accuracy of a diagnostic test when an imperfect reference test with known classification errors is available. Furthermore, we focus our presentation on available methods of estimation of test characteristics when the sensitivity and specificity of both tests are unknown. We present some of the available statistical methods for estimation of the accuracy of diagnostic tests when a reference test does not exist (including maximum likelihood estimation and Bayesian inference). We illustrate the application of the described methods using data from an evaluation of a nested polymerase chain reaction and microscopic examination of kidney imprints for detection of Nucleospora salmonis in rainbow trout. 相似文献
145.
We investigated the effect of raising runt white sturgeon (Acipenser transmontanus) separately from dominant fish during the initial stages of grow-out in a commercial farm. Runt fish are poor-growers, have underdeveloped muscle mass, swim slowly and are more-frequently found at the top of the water column. The objective of the study was to describe the mortality and recovery rates (and their determinants) of white-sturgeon runts after separating them from dominant fish. Runt white sturgeon were stocked into twelve 2 m × 2 m rectangular tanks and graded periodically during a follow-up of 46–102 days. Overall mortality rates ranged from 0.3 to 7 dead fish per 1000 sturgeon-days at risk and overall recovery rates from 3.9 to 13.5 recovered fish per 1000 sturgeon-days at risk. Period-specific mortality and recovery rates increased over time. The period-specific mortality rates for all three periods were significantly higher for tanks of runts originating from grow-out tanks with high mortality (p-values: first period = 0.06; second period = 0.09; third period = 0.03), but were similar for tanks of runts of high- and low-mean initial weight. The period-specific recovery rates were significantly higher in runts originating from high-mortality grow-out tanks only for the third period (p = 0.05) but not the first and second periods (p-values = 0.33 and 0.25, respectively). Recovery rates were significantly higher in the higher-mean-weight runts tanks for the first and third period but not for the second (p-values: first period = 0.02; second period = 0.65; third period = 0.06). We concluded that the proportion of runts that recover during a 46–89 day period is substantial (16–58%); therefore, it might be worthwhile growing such fish separately in a fish farm for about three months. Financial analysis showed that this practice was profitable, if the value of white sturgeon fish for the farm exceeded $2.05 per kg. 相似文献
146.
Stockham SL Kjemtrup AM Conrad PA Schmidt DA Scott MA Robinson TW Tyler JW Johnson GC Carson CA Cuddihee P 《Veterinary pathology》2000,37(1):11-21
A 6-year-old Simmental cow infected with Theileria buffeli had a clinical disease characterized by theilerial parasitemia, macrocytic normochromic anemia with acanthocytosis and spherocytosis, lymphoid hyperplasia (lymphocytosis, edematous lymphadenomegaly), dysproteinemia, evidence of liver disease, and a low serum antibody titer against T. buffeli. The cow was in a herd in which all cattle originated in Missouri; 22/75 (29%) of cattle had a theilerial parasitemia and 26/75 (35%) had titers to T. buffeli of > or =1:160. Classification of the Missouri bovine organism as T. buffeli was based on DNA sequencing and comparison to sequences for T. buffeli and Theileria sp. type A obtained from GenBank. Intraerythrocytic veils and piroplasms were seen during transmission electron microscopy. The organism was successfully transmitted to two splenectomized calves, which developed mild anemias while parasitemic. Blood from the second calf was used as the source of T. buffeli antigen for an indirect immunofluorescence antibody test. Theilerial isolates from a Missouri white-tailed deer were also sequenced and resembled Theileria sp. types F and G and were not consistent with the bovine organism. 相似文献
147.
Singer RS Jeffrey JS Carpenter TE Cooke CL Atwill ER Johnson WO Hirsh DC 《Veterinary microbiology》2000,75(1):59-71
Avian cellulitis in broiler chickens is primarily caused by Escherichia coli. Previous research found that the E. coli isolates of cellulitis origin were unique to each ranch, suggesting that these E. coli were endemic within the ranch environment. To test the hypothesis that the E. coli associated with cellulitis are endemic in the litter of the broiler house, we designed a study to determine whether E. coli DNA fingerprints associated with cellulitis persist over successive flocks that are grown in the same house. In addition, we assessed the impact of different cleaning and disinfection strategies on this persistence. Two broiler houses were followed on each of five farms over 3-4 flocks. A total of 353 E. coli isolates from cellulitis lesions were analyzed in this study, and 314 of these isolates (89%) were DNA fingerprinted by PFGE. In each ranch, there were several DNA fingerprint patterns that were present over successive flocks, regardless of the cleaning and disinfection strategy utilized. Isolates persisted as long as 191 days, implying that these E. coli are capable of persisting in the broiler house environment for long periods of time. In addition, these E. coli isolates were associated with cellulitis lesions in successive flocks. Thus, the isolates of E. coli that are associated with cellulitis in broiler chickens appear to be endemic in the litter environment of the broiler house. 相似文献
148.
Norris CR Williams BJ Ling GV Franti CE Johnson Ruby AL 《Journal of the American Animal Hospital Association》2000,36(6):484-492
Laboratory records of bacterial urine cultures from 383 dogs with recurrent or persistent urinary tract infections (UTI) diagnosed at the University of California Veterinary Medical Teaching Hospital (VMTH) between 1969 and 1995 were reviewed retrospectively to characterize the bacteria involved and their association with age, gender, and breed of dogs affected. Sixty-eight breeds and a mixed-breed group were represented. Escherichia coli was the most common isolate, although mixed-bacterial infections were seen in 58% of the female and 55% of the male dogs. Recurrent and persistent UTI were most prevalent in middle-aged to older German shepherd dogs, miniature/toy poodles, and Labrador retrievers, with no apparent sex predilection. Criteria fitting recurrent and persistent UTI were present in 0.3% of all dogs seen at the VMTH during this 26-year period. 相似文献
149.
ABSTRACT Alternaria alternata apple pathotype (previously A. mali) causes Alternaria blotch on susceptible apple cultivars through the production of a host-specific toxin, AM-toxin. Identification of some Alternaria species, especially those that produce host-specific toxins, has been extremely difficult due to a high level of variability which extends even to nonpathogenic isolates. We have recently cloned and characterized a gene (AMT) that plays a crucial role in AM-toxin biosynthesis and demonstrated that it is only present in isolates of A. alternata apple pathotype. Using primers designed for the AMT gene, we developed a polymerase chainreaction-based method to specifically detect AM-toxin producing isolates of A. alternata apple pathotype. 相似文献
150.
Dystocia in the class Reptilia is a common problem. In turtles, it is often difficult to distinguish between a normal gravid state and dystocia. This case report describes nonobstructive dystocia in a free-living freshwater chelonian, Chelodina longicollis, complicated by traumatic injuries to the head, bridge, and plastron. Medical treatment of the dystocia and external fixation of the facial injuries provided a successful outcome. 相似文献