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41.
Arginine-utilising mycoplasmas isolated from the pneumonic lungs of 4 pigs were identified as M. hyosynoviae by their growth characteristics, biochemical activity and serological similarity to each other and to 2 type strains of M. hyosynoviae in growth inhibition tests. A purified culture of one M. hyosynoviae isolate was inoculated intravenously into 3 pigs which were killed 9 days later. Although arthritis was not observed clinically, M. hyosynoviae was isolated from 8 of 9 joints cultured, the tonsils and retropharyngeal lymph nodes of all 3 pigs and the lungs of 2 pigs. No histopathological changes were observed in synovial membranes of the joints cultured or lungs but severe depletion of lymphocytes in the cortex of lymphoid follicles in lymph nodes and tonsils was observed.  相似文献   
42.
Antibody detection-based tests for paratuberculosis offer speed and economy, 2 diagnostic test attributes important to animal industries with narrow profit margins. Application of such tests to individual milk samples instead of serum samples can further improve testing efficiency and decrease testing cost. Accuracy of a commercial bovine paratuberculosis enzyme-linked immunosorbent assay (ELISA) adapted for use on goat serum and milk samples was determined. Fecal, blood, and milk samples were collected from 159 goats belonging to 2 Wisconsin goat herds with a prior history of paratuberculosis and 1 herd of 50 goats from a paratuberculosis-free Wisconsin herd. Fecal samples were cultured using the modified BACTEC 12B media. Sera were tested according to the manufacturer's instructions for bovine samples. Milk samples were centrifuged and mixed with the ELISA kit's Mycobacterium phlei-containing diluent at a ratio of 1:2. Using fecal culture as the "gold standard," the sensitivity of the ELISA on goat serum was 64% and the sensitivity of the ELISA on goat milk was 48%. The milk ELISA had higher agreement with fecal culture results (kappa = 0.525) than the serum ELISA (kappa = 0.425). ELISA specificity was 100% on both serum and milk. Regression analysis also showed good correlation between serum and milk S/P values (r2 = 0.67). Although less sensitive, the ELISA on goat milk samples appears to offer a useful, low-cost alternative for detection of goats with paratuberculosis that have progressed to the stage of shedding M. paratuberculosis in their feces.  相似文献   
43.
1. Conventional or gnotobiotic chicks, when injected from 1 d to 3 weeks of age with adrenocorticotrophic hormone (120IU/kg, three times weekly), showed a depressed growth rate, adrenal hypertrophy and depletion of cholesterol form the adrenal glands. 2. Feeding a diet supplemented with aureomycin (10 mg/kg) did not have any consistent ameliorating effect on the response of the stressed bird as judged by the above parameters. 3. It was found that treating germfree chicks with five daily injections of sterile milk on days 3 to 7 did not depress growth rate at any time, nor could differences in adrenal size or cholesterol stores be detected at the end of the 21-d experimental period. The responses were not modified by feeding an aureomycin-supplemented diet.  相似文献   
44.
The amounts of p,p′-DDT and of five other trichloroethane derivatives decreased upon incubation under anaerobic conditions with 12,000g × 30 min pigeon liver supernatant fraction. The addition of an exogenous NADPH-generating system sometimes, but not invariably, increased the rate of metabolism. Only one hexane-soluble metabolite was detected in the postincubation reaction medium of each of the six trichloroethane derivatives. After isolation by tlc the six metabolites were shown by mass spectrometry to have molecular weights 34 units less than their parent compounds. Comparison of the isotope patterns in the spectra of each substrate and its metabolite reveals that in each case the metabolism involves the loss of a chlorine atom. From these data it is concluded that several substituted trichloroethanes undergo reductive dechlorination when they are incubated with liver preparations in an atomosphere of nitrogen. Two dichloroethane derivatives, tested in a similar manner, were unchanged and were recovered quantitatively. Mass spectrometric and chromatographic data of reactants and products are recorded.  相似文献   
45.
1. Treating chicks, from 1 d or 5 weeks of age with ACTH three times weekly for 3 weeks depresses growth and causes adrenal hypertrophy at dose rates of 30 IU/kg or more, and depletion of adrenal cholesterol (greater than 10 IU/kg). 2. Treating chicks five times weekly at a dose rate of 30 IU/kg was as effective as a dose of 120 IU/kg three times weekly. 3. Plasma glucose and FFA concentrations of chicks treated thrice weekly with 120 IU ACTH/kg for 3 weeks were within the normal range. 4. Rhode Island Reds were more sensitive to ACTH than Light Sussex. 5. Adrenal cholesterol stores in normal chicks show significant variations with season.  相似文献   
46.
Gunduz I  Buss GR  Chen P  Tolin SA 《Phytopathology》2004,94(7):687-692
ABSTRACT Resistance to Soybean mosaic virus (SMV) was identified in PI 88788 soybean, a germ plasm accession from China that is used widely as a source of resistance to soybean cyst nematode. Strains SMV-G1 through -G7 infected the inoculated leaves of PI 88788 but were not detected in upper, noninoculated trifoliolate leaves. Inheritance of resistance was determined by inoculating progenies of crosses of PI 88788 with susceptible cvs. Essex and Lee 68 with SMV strains G1 and G7. Allelomorphic relationships with known genes for resistance to SMV were tested in crosses with the resistant genotypes PI 96983, L29, and V94-5152, possessing Rsv1, Rsv3, and Rsv4 genes, respectively. Data analyses showed that resistance in PI 88788 to SMV-G1 is controlled by a single, partially dominant gene; however, to SMV-G7, the same gene was completely dominant. The PI 88788 gene was independent of the Rsv1 and Rsv3 loci, but allelic to Rsv4 in V94-5152. Expression of the Rsv4 gene in PI 88788 resulted in a reduced number of infection sites and restricted short- and long-distance movement of virus, rather than hypersensitivity. A unique late susceptible phenotype was strongly associated with heterozygosity. This gene has potential value for use in gene pyramiding to achieve resistance to several SMV strains, as well as for rate-reducing resistance.  相似文献   
47.
The responses of 15 cats with histologically (n=14) or cytologically (n=1) confirmed nasal squamous cell carcinoma treated with (90)Strontium plesiotherapy were reviewed retrospectively. Cats were treated such that a total dose of 50Gy was delivered at a depth of 2mm, administered in five fractions over a 10-day period. Of the cats, 11 were stage T(2), three were T(is) and one had only a cytological diagnosis precluding staging. Eleven of the cats achieved complete response (no visible lesion after 6-8 weeks) following the first cycle of therapy, and two cats with partial response achieved complete response with a second cycle of therapy. The remaining two cats achieved partial response following therapy, but further intervention was declined. Euthanasia was performed in these two cats because of progressive disease after 81 and 142 days. Of the 85% of cats that achieved a complete response, there was no recurrence of disease during a follow-up period of 134-2,043 days (median 652 days). In addition to prolonged disease-free survivals, (90)Strontium therapy produced excellent cosmetic results from the owners' perspective. These results demonstrate that superficial squamous cell carcinoma of the feline nasal planum responds excellently to (90)Strontium plesiotherapy, and this form of therapy may offer advantages over other alternatives currently available.  相似文献   
48.
CASE DESCRIPTION: A 5-year-old sexually intact male cockatiel was examined because of progressive dyspnea of 1 week's duration. CLINICAL FINDINGS: On auscultation of the lungs and air sacs, crackles were detected; the abdomen was distended and fluctuant on palpation. Eleven milliliters of clear yellow fluid was collected via abdominocentesis. Radiography (with and without contrast medium) and ultrasonography revealed a soft tissue mass in the caudoventral portion of the coelom. TREATMENT AND OUTCOME: Exploratory surgery of the coelomic cavity was performed and the neoplasm was excised. Histologic examination of the neoplasm was consistent with a high-grade pancreatic exocrine adenocarcinoma. Celecoxib, a cyclooxygenase (COX)-2 inhibitor, was administered for pain management and for potential antineoplastic activity. For 4.5 months after surgery, the bird had no recurrence of clinical signs; however, dyspnea recurred and during evaluation, the bird died. Necropsy findings indicated that the pancreatic adenocarcinoma had metastasized to surrounding tissues and vessels, which was not unexpected given the high grade assigned to the neoplasm during histologic analysis. CLINICAL RELEVANCE: Pancreatic neoplasms are associated with a poor prognosis, regardless of treatment modality. Celecoxib can be administered as palliative treatment to affected birds, but as with any nonsteroidal anti-inflammatory drug, COX-2 inhibitors should be used cautiously because they can adversely affect renal function by decreasing renal prostaglandin synthesis.  相似文献   
49.
OBJECTIVE: To evaluate the pharmacokinetic-pharmacodynamic parameters of enrofloxacin and a low dose of amikacin administered via regional IV limb perfusion (RILP) in standing horses. ANIMALS: 14 adult horses. PROCEDURES: Standing horses (7 horses/group) received either enrofloxacin (1.5 mg/kg) or amikacin (250 mg) via RILP (involving tourniquet application) in 1 forelimb. Samples of interstitial fluid (collected via implanted capillary ultrafiltration devices) from the bone marrow (BMIF) of the third metacarpal bone and overlying subcutaneous tissues (STIF), blood, and synovial fluid of the radiocarpal joint were collected prior to (time 0) and at intervals after tourniquet release for determination of drug concentrations. For pharmacokinetic-pharmacodynamic analyses, minimum inhibitory concentrations (MICs) of 16 microg/mL (amikacin) and 0.5 microg/mL (enrofloxacin) were applied. RESULTS: After RILP with enrofloxacin, 3 horses developed vasculitis. The highest synovial fluid concentrations of enrofloxacin and amikacin were detected at time 0; median values (range) were 13.22 microg/mL (0.254 to 167.9 microg/mL) and 26.2 microg/mL (5.78 to 50.0 microg/mL), respectively. Enrofloxacin concentrations exceeded MIC for approximately 24 hours in STIF and synovial fluid and for 36 hours in BMIF. After perfusion of amikacin, concentrations greater than the MIC were not detected in any samples. Effective therapeutic concentrations of enrofloxacin were attained in all samples. CONCLUSIONS AND CLINICAL RELEVANCE: In horses with orthopedic infections, RILP of enrofloxacin (1.5 mg/kg) should be considered as a treatment option. However, care must be taken during administration. A dose of amikacin > 250 mg is recommended to attain effective tissue concentrations via RILP in standing horses.  相似文献   
50.
The association between high malting quality and pre-harvest sprouting (PHS) susceptibility is a key challenge when developing new malting barley varieties. A new malting barley variety Baudin has successfully combined high malting quality and PHS tolerance. A doubled haploid population was developed for mapping PHS tolerance and seed dormancy from a cross of Baudin?×?AC Metcalfe using 233 molecular markers. Three QTLs were mapped for seed dormancy based on the standard germination test at 24, 48 and 72?h. One major QTL was mapped to the long arm of chromosome 5H controlling seed dormancy and PHS tolerance from Baudin. Two other minor QTLs were identified from Baudin on chromosomes 3 and 7H. QTL/QTL interaction was detected for seed dormancy between chromosomes 3 and 5H. The PHS tolerance allele of the 5H QTL from Baudin contributes to higher malt yield without significant impact on diastatic power, beta-glucan content and wort viscosity. QTL from Baudin provide new sources to integrate PHS tolerance and high malting quality.  相似文献   
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