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151.
152.
S A Center C A Smith E Wilkinson H N Erb R M Lewis 《Journal of the American Veterinary Medical Association》1987,190(1):81-90
In a 10-year retrospective study, we evaluated the clinicopathologic features and renal immunofluorescence patterns of glomerulonephritis in 41 dogs. On the basis of results of histologic examinations, the dogs were segregated into 3 groups, including membranous (n = 12), mesangioproliferative (n = 15), or membranoproliferative glomerulonephritis (n = 14). No significant differences existed among groups in regard to age or duration of illness. Most dogs had been ill for one month or longer. The proportion of dogs with azotemia, anemia, and hyperphosphatemia were not different among the disease groups. Proportion of dogs with hypoalbuminemia and the severity of hypoalbuminemia were not different among groups. Highest urine protein losses and 24-hour urine protein/creatinine ratios developed in dogs with membranous glomerulonephritis. Although hypoalbuminemia and hypercholesterolemia were common (49%), the formation of edema or ascites was not (15%) and, therefore, few dogs had all of the classic features of the nephrotic syndrome. Few dogs suffered thromboembolic complications. Antinuclear antibody titers developed in 11 dogs, the highest titers developing in dogs with polyarthritis and systemic lupus erythematosis. Cellulose acetate electrophoresis detected alpha 2 and beta 1 globulin spikes in most dogs (87%). Results of renal immunofluorescence testing were positive in 36 dogs, using polyvalent antisera for immunoglobulins (Ig)G, IgA, IgM, and/or antisera for complement factor C3. When monovalent antisera for IgG, IgA, and IgM, and fibrinogen were used, immunofluorescence was not observed as often. The major fluorescent pattern was discrete multifocal segmental granular glomerular fluorescence, consistent with immune-complex deposition. Two dogs had linear glomerular staining patterns; however, antibodies directed against normal glomerular basement membrane were not found via elution studies. A high prevalence of glucocorticoid excess (treatment with glucocorticoids and spontaneous hyperadrenocorticism) (34%), chronic inflammatory skin disease (27%), neoplasia (17%), polyarthritis (12%), and systemic lupus erythematosis (7%) were observed as clinical problems concurrent with glomerulonephritis. In 5 dogs, treatment of glomerulonephritis with prednisolone (0.5 to 1.1 mg/kg) did not result in beneficial effects and in fact appeared to be detrimental, leading to azotemia and worsening proteinuria and physical condition in some of the dogs.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
153.
R P Del Vecchio D J Matsas T J Inzana D P Sponenberg G S Lewis 《Journal of animal science》1992,70(10):3158-3162
Multiparous Angus and crossbred Angus cows were used to determine the effect of induced endometritis on plasma concentrations of 13,14-dihydro-15-keto-prostaglandin F2 alpha (PGFM) and progesterone (P4) and on duration of the estrous cycle of treatment. Beginning on the day of calving (d 0), blood samples were collected on alternate days. On three consecutive days, ranging from d 8 to 14 of the first postpartum estrous cycle, uterine horns were inoculated transcervically with either 3 x 10(9) colony forming units (cfu) of Actinomyces pyogenes and 1.5 x 10(9) cfu of beta-hemolytic Escherichia coli (treated; n = 9) in sterile PBS or with sterile PBS alone (control; n = 9). Samples of uterine fluid were collected by transcervical aspiration twice weekly from just before the start of each series of inoculations until the end of the experiment. Endometrial biopsies were collected transcervically between d 4 to 6 and 11 to 13 after inoculation. Based on clinical observations and results of bacterial cultures, all treated cows developed acute uterine infections. Controls did not develop uterine infections. Endometrial biopsies indicated that there were no significant diffuse or focal cellular reactions in response to the infection. The interestrous interval was greater (P less than .0003) for treated (27.7 +/- 1.0 d) than for control (20.6 +/- 1.0 d) cows, but P4 concentrations were similar between the two groups. Mean PGFM concentration and PGFM profiles were similar (P greater than .10) between treated and control cows before bacterial infusions. Bacterial infusions increased mean PGFM concentration (P less than .0001) and changed the shape of the PGFM profile (P less than .02).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
154.
1. Egg production records of 31,455 individually caged hens, 27 to 34 weeks of age and of 4 genotypes, were examined. 2. Sixty-nine non-layers were identified in the 30 to 40 week age group, and examined post mortem; an incidence of 2.1 per 1000. 3. Some of the 69 individuals had more than one abnormality. Forty-two percent were internal layers, 34% had some form of neoplasia, 24% had an abnormal or diseased oviduct, 18% were sex reversals, 16% had a diseased ovary, 8% were of poor condition and considered culls, and 7% were in good condition, but with small, immature ovaries. 4. Of 54 birds not in lay at 27 weeks, 43 (80%) had come into lay by 34 weeks of age. 5. Genotype influenced the incidence of neoplasia and, in turn, the number of non-layers. 相似文献
155.
Sethunathan N Megharaj M Chen ZL Williams BD Lewis G Naidu R 《Journal of agricultural and food chemistry》2004,52(10):3030-3035
The role of algae in the persistence, transformation, and bioremediation of two endocrine disrupting chemicals, alpha-endosulfan (a cyclodiene insecticide) and its oxidation product endosulfan sulfate, in soil (incubated under light or in darkness) and a liquid medium was examined. Incubation of soil under light dramatically decreased the persistence of alpha-endosulfan and enhanced its transformation to endosulfan sulfate, over that of dark-incubated soil samples, under both nonflooded and flooded conditions. This enhanced degradation of soil-applied alpha-endosulfan was associated with profuse growth of indigenous phototrophic organisms such as algae in soil incubated under light. Inoculation of soil with green algae, Chlorococcum sp. or Scenedesmus sp., further enhanced the degradation of alpha-endosulfan. The role of algae in alpha-endosulfan degradation was convincingly demonstrated when these algae degraded alpha-endosulfan to endosulfan sulfate, the major metabolite, and endosulfan ether, a minor metabolite, in a defined liquid medium. When a high density of the algal inoculum was used, both metabolites appeared to undergo further degradation as evident from their accumulation only in small amounts and the appearance of an endosulfan-derived aldehyde. Interestingly, beta-endosulfan was detected during degradation of alpha-endosulfan by high density algal cultures. These algae were also capable of degrading endosulfan sulfate but to a lesser extent than alpha-endosulfan. Evidence suggested that both alpha-endosulfan and endosulfan sulfate were immediately sorbed by the algae from the medium, which then effected their degradation. Biosorption, coupled with their biotransformation ability, especially at a high inoculum density, makes algae effective candidates for remediation of alpha-endosulfan-polluted environments. 相似文献
156.
Lewis RE van Walsum KL Spafford MM Edwards JC Turnwald GH 《Journal of veterinary medical education》2004,31(2):128-137
The veterinary school admission interview is a widely used selection tool, yet concerns persist about its reliability, validity, and cost. Relative to medicine, optometry, and dentistry schools, veterinary schools have been more likely to conduct panel interviews and to fix the interview's weight in selection decisions, strategies that increase interview validity. This article provides strategies for further increasing the veterinary school interview's validity. Interview reliability and validity studies point to key strategies the veterinary school admissions committee can implement before the interview: (1) establishing the interview's purpose(s); (2) conducting a "job" analysis to identify desirable candidate skills, knowledge, and attributes; (3) developing a structured and panel interview where interviewers, if possible, are blind to other admission data; (4) training interviewers; (5) setting a reasonable interview schedule; and (6) determining methods for analyzing applicant data. During the interview, interviewers should proceed through a structured series of steps: (1) open the interview with a specified agenda; (2) probe for information using structured questions and anchored rating scales; (3) close the interview to allow for candidate questions; and (4) evaluate the interview data. After the interview, the admissions committee should (1) analyze the interview data within and across interviewers and (2) analyze the data across all selection tools in order to assign relative weights to the selection tools. 相似文献
157.
Terrell SP Sundeep Chandra AM Pablo LS Lewis DD 《Journal of the American Animal Hospital Association》2004,40(4):345-348
A 3-year-old, German shepherd dog died suddenly during cemented total hip arthroplasty. Gross necropsy findings included severe pulmonary edema and congestion as well as congestion of the liver and kidneys. Acute pulmonary embolism was suspected as the cause of death. Microscopic examination of hematoxylin and eosin-stained, formalin-fixed, and oil red O-stained frozen tissue sections confirmed the presence of large numbers of fat globules in blood vessels in the lungs, liver, and kidneys. Fat embolism during total hip arthroplasty is a common surgical complication in humans, but it is uncommon in veterinary cases and is rarely a cause of death. 相似文献
158.
159.
160.
Lewis CJ 《The Veterinary record》2006,158(2):71-2; author reply 72