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41.
Ten dogs suffered acute renal failure after ingesting > or = 3 g/kg (dry matter) of grapes or raisins. All dogs had degeneration or necrosis (or both) of proximal renal tubules with basement membranes remaining intact, and epithelial regeneration was observed in 5 out of 10 cases. Mineralized tubular debris or granular to proteinaceous casts (or both) were present in all cases. A golden-brown, globular, intracellular pigment of varying amounts and sizes was observed in 6 out of 10 cases with variable reaction with Prussian blue. Multifocal fibrinous arteritis of the large colon was seen in 2 out of 5 cases with globulin insudation of vessel wall demonstrated by immunohistochemical staining for immunoglobulin (Ig)G and IgM. Mineral analysis on frozen renal tissue from 2 out of 2 cases revealed mildly elevated Ca:P ratio in both. Clinically significant observations were preservation of the integrity of basement membranes after grape-induced tubular injury and presence of early epithelial regeneration. Thus, recovery may be possible if anuria is aggressively managed. With respect to potential pathophysiologic mechanisms, further research into the roles of calcium homeostasis, vascular reactivity, and the significance of the golden-brown pigment is indicated.  相似文献   
42.
The use of cysteine proteinases from Fasciola hepatica adult flukes for the serodiagnosis of caprine fasciolosis by means of an indirect ELISA test was studied. Two proteolytic fractions from adult fluke homogenates, with apparent molecular weights of 28 and 34 kDa (P28 and P34 respectively), were characterised as cysteine proteinases using azocasein assays and gelatin gel analysis. Both P28 and P34 fractions were electroluted and used as antigens in two different indirect ELISA tests. Serum IgG levels against P28 and P34 in goats given an experimental primary infection with 200 metacercariae or in goats given two experimental infections with 200 metacercariae were determined and compared with those observed in an uninfected control group. ELISA tests using both cysteine proteases showed a rapid and consistent detection of specific IgG in all experimentally infected goats. The IgG response to P28 was the first to be detected as early as 2-3 weeks post-infection and remained elevated throughout the experiment. The response to P34 was detected later (4-6 wpi) and disappeared in some animals at 18 wpi, while flukes were still present in the bile ducts. No significant differences were observed between the anti-P28 and anti-P34 IgG responses between animals receiving a primary or a challenge infection. The results of our study, although preliminary, are promising since the P28 ELISA described here may be a reliable method for the immunodiagnosis of F. hepatica infection in goats.  相似文献   
43.
We investigated the therapeutic effects of a progesterone releasing intravaginal device (PRID) on cystic ovarian disease (COD) and reproduction performance of cows. The possible influence of PRID on metabolic and/or health status was also examined. A total of 40 Holstein-Friesian cattle, with ovarian cystic structures, > or =2.5 cm in diameter, persisting for more than 7-14 days, without a corpus luteum (CL) were used for the study. PRID or placebos were inserted into the vagina for 12 days. Five animals lost the intravaginal device before removal and one was culled. Based on plasma progesterone concentration on the day of treatment, 20 (17 PRID and 3 placebos) of the remaining 34 cows had follicular cysts (progesterone < or =1 ng/ml) and 14 (10 PRID and 4 placebos) had luteal cysts (progesterone >1 ng/m l). Fourteen (82%) of the PRID-treated follicular cystic cows responded with formation of a CL within 14 days after treatment, and an overall conception rate of 53.8%. Likewise, 70% of the treated luteal cystic cows responded with CL formation and 71.4% conception rate. No significant differences were observed in hematocrit (Ht), white blood cell count and serum levels of glucose, blood urea nitrogen, aspartate aminotransferase, and alanine aminotransferase, between the day of PRID insertion and removal, in animals with follicular and luteal cysts. PRID treatment resulted in ovulation 2-4 days later and formation of a CL in cows that recovered.  相似文献   
44.
45.
Primary porcine endothelial cells have a limited life span in culture. After four to five passages, they tend to de-differentiate and eventually reach senescence. The aim of this work was to establish immortalized porcine aortic endothelial cell lines (AOCs) to facilitate in vitro studies of different pathological process involving the endothelium. Primary porcine aortic endothelial cells (PAECs) were transfected with a plasmid containing the SV40 genome and selected on the basis of morphological and phenotypical features. Flow cytometry analysis demonstrated uptake of acetylated low density lipoproteins (Ac-LDL) and constitutive expression of SLA class I, CD29, CD31, CD41/61, CD80/86, CD46, SWC3, and LAMP-1 antigens by all analyzed lines and showed little differences to primary cells. The functional similarity between primary and immortalized endothelial cells was demonstrated in a cytotoxicity assay using a human natural killer cell line (NKL) as effector. The AOCs cell lines should be valuable tools for in vitro study of the human immune response against pig endothelial cells. In addition, they would be very useful to gain insight in the pathogenesis of some viral haemorrhagic diseases of pig such as African swine fever (ASF) or classical swine fever (CSF).  相似文献   
46.
Immunity to Taenia solium infection was investigated using an experimental intramuscular oncosphere infection assay (IMOA) model in pigs. Three naturally infected pigs with cysticercosis were treated with oxfendazole (OFZ), a drug demonstrated to kill cysts in porcine muscle. These animals were then challenged with oncospheres but did not develop any cysts while three uninfected pigs that were similarly challenged, did develop intramuscular cysts. In another study, two groups of three pigs each were immunized with crude T. solium oncosphere and metacestode antigens, respectively, and tested with the IMOA. Immunization with crude oncosphere antigens (OAs) induced 100% protection, while metacestode antigens provided only partial protection. Immunoblots showed that pigs with complete immune protection to oncosphere intramuscular challenge had antibodies to two OAs at 31.3 and 22.5 kDa, respectively. Antibody to these two antigens was absent in pigs immunized with metacestodes or in uninfected control pigs. This study demonstrated the presence of two antigens that are unique to the oncosphere. Although, antibody to these two antigens is consistently present in pigs that are protected from an oncosphere intramuscular challenge their role in preventing infection by T. solium larval cysts is still hypothetical.  相似文献   
47.
Practicing veterinarians in small-animal or mixed-animal practice in New York state were surveyed about their beliefs and practices regarding the age at which dogs and cats should be neutered and their attitudes toward early neutering (at 4 months of age or younger). The majority of veterinarians routinely recommended neutering for all client animals (70.6%) and supported the routine neutering of shelter animals before adoption (90.3%). More veterinarians in this study reported at least one perceived benefit (91.3%) for early neutering than reported at least one perceived risk (84.4%). Veterinarians with experience neutering early were less likely to believe that the procedure was associated with one or more risks.  相似文献   
48.
Genotyping of Mycobacterium bovis by geographic location within Mexico   总被引:1,自引:0,他引:1  
The spacer oligonucleotide typing (spoligotyping) method was used to differentiate 62 Mycobacterium bovis isolates obtained from tissues with macroscopic lesions typical of tuberculosis in dairy cattle from different regions of Mexico. Our purpose was to see if a strain from one region was genetically different from those of other regions (with the long-term aim of doing molecular trace back of isolates obtained in the laboratory). Results from the genetic analysis indicate that M. bovis isolates cannot be grouped by geographic location due to a wide range of genetic types involved in dairy cattle infections. Isolates even from the same herd showed different spoligotypes but some isolates from different region had similar genetic patterns. Genetic typing without epidemiologic information does not seem to be a plausible method to trace back animals to source of origin to detect and eliminate sources of infection.  相似文献   
49.
ABSTRACT Mixed infections of cucurbits by Cucumber mosaic virus (CMV) and potyviruses exhibit a synergistic interaction. Zucchini squash and melon plants coinfected by the potyvirus Zucchini yellow mosaic virus (ZYMV) and either Fny-CMV (subgroup IA) or LS-CMV (subgroup II) displayed strong synergistic pathological responses, eventually progressing to vascular wilt and plant death. Accumulation of Fny- or LS-CMV RNAs in a mixed infection with ZYMV in zucchini squash was slightly higher than infection with CMV strains alone. There was an increase in CMV (+) strand RNA levels, but no increase in CMV (-) RNA3 levels during mixed infection with ZYMV. Moreover, only the level of capsid protein from LS-CMV increased in mixed infection. ZYMV accumulated to similar levels in singly and mixed infected zucchini squash and melon plants. Coinfection of squash with the potyvirus Watermelon mosaic virus (WMV) and CMV strains increased both the Fny-CMV RNA levels and the LS-CMV RNA levels. However, CMV (-) strand RNA3 levels were increased little or not at all for CMV on coinfection with WMV. Infection of CMV strains (LS and Fny) containing satellite RNAs (WL47-sat RNA and B5*-sat RNA) reduced the accumulation of the helper virus RNA, except when B5*-sat RNA was mixed with LS- CMV. However, mixed infection containing ZYMV and the CMV strains with satellites reversed the suppression effect of satellite RNAs on helper virus accumulation and increased satellite RNA accumulation. The synergistic interaction between CMV and potyviruses in cucurbits exhibited different features from that documented in tobacco, indicating there are differences in the mechanisms of potyvirus synergistic phenomena.  相似文献   
50.
An epizootiological survey of necropsied cases (1993-1997) at University of the Philippines was performed. A total of 368 cases included 238 avian and 111 porcine cases. Amongst avian cases, the major cause of death was infectious diseases in 212 (89%) cases including 97 (41%) bacterial, 36 (15%) viral, and 21(9%) parasitic diseases. The majority of the avian bacterial diseases presented as septicemia (73 cases) and the viral diseases as Newcastle disease (17 cases). In porcine cases, the major cause of death was also infectious diseases, in 100 (90%) cases including 52 bacterial and 29 viral diseases. Porcine bacterial diseases were classified into 36 septicemia, 4 hemophillosis and 4 colibacillosis. Amongst the porcine viral diseases, most cases were diagnosed as Hog cholera (22 cases).  相似文献   
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