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Healthy ruminants carry intestinal Shiga toxin (Stx)-producing Escherichia coli (STEC). Stx has antiviral activities in vitro and STEC numbers correlate with reduced early viremia in sheep experimentally infected with bovine leukemia virus (BLV). This study assessed the impact of intestinal STEC on BLV-induced disease for one year post-BLV-challenge. High STEC scores (CFU/g feces × frequency of STEC-positive samples) correlated with good health, whereas poor weight gain, distress, and tumor development occurred only among animals with low STEC scores. STEC carriage was associated with increased percentages of B cells in peripheral blood.  相似文献   
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Objective— To describe the clinical features and determine oncologic outcome and prognostic factors for dogs with primary tumors of the osseous chest wall. Study Design— Historical cohort. Animals— Dogs (n=39) with spontaneous tumors involving the chest wall. Methods— Medical records were reviewed for dogs with rib and/or sternal tumors treated by chest wall resection and reconstruction. Signalment, preoperative clinical features, reconstruction technique, and oncologic outcome (local tumor recurrence, metastasis, and survival time) were determined from medical records and by telephone contact with owners and referring veterinarians. Oncologic outcome and prognostic factors were determined using Kaplan–Meier survival analysis and Cox proportional hazards. Logistic regression was used to determine if increased serum alkaline phosphatase (ALP) concentration was associated with tumor type. Results— Of the 39 dogs with tumors arising from the chest wall, 25 had osteosarcoma, 12 had chondrosarcoma, and 2 dogs had hemangiosarcoma. Median survival time (MST) for dogs with rib osteosarcoma was 290 days. Increased activity of total ALP significantly decreased survival in dogs with osteosarcoma (210 days versus 675 days, P=.0035). MST for dogs with rib chondrosarcoma was not reached (mean 1301 days) and survival was significantly greater than all other types of rib tumors (P=.0321). Conclusion— Rib tumors should be resected with wide margins to decrease the risk of incomplete excision, because local tumor recurrence has a significant impact on the survival time. The prognosis for dogs with rib chondrosarcoma is very good, but guarded for other types of tumors. Clinical Relevance— Osteosarcoma and chondrosarcoma are the most common primary tumors of the chest wall. Prognosis for dogs with primary rib chondrosarcoma is very good with surgery alone, but surgery and adjunctive chemotherapy is recommended for dogs with primary rib osteosarcoma and the prognosis remains guarded.  相似文献   
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To examine effects of nutrient restriction and dietary Se on maternal and fetal visceral tissues, 36 pregnant Targhee-cross ewe lambs were allotted randomly to 1 of 4 treatments in a 2 x 2 factorial arrangement. Treatments were plane of nutrition [control, 100% of requirements vs. restricted, 60% of controls] and dietary Se [adequate Se, ASe (6 microg/kg of BW) vs. high Se, HSe (80 microg/kg of BW)] from Se-enriched yeast. Selenium treatments were initiated 21 d before breeding and dietary restriction began on d 64 of gestation. Diets contained 16% CP and 2.12 Mcal/kg of ME (DM basis) and differing amounts were fed to control and restricted groups. On d 135 +/- 5 (mean +/- range) of gestation, ewes were slaughtered and visceral tissues were harvested. There was a nutrition x Se interaction (P = 0.02) for maternal jejunal RNA:DNA; no other interactions were detected for maternal measurements. Maternal BW, stomach complex, small intestine, large intestine, liver, and kidney mass were less (P < or = 0.01) in restricted than control ewes. Lung mass (g/kg of empty BW) was greater (P = 0.09) in restricted than control ewes and for HSe compared with ASe ewes. Maternal jejunal protein content and protein:DNA were less (P < or = 0.002) in restricted than control ewes. Maternal jejunal DNA and RNA concentrations and total proliferating jejunal cells were not affected (P > or = 0.11) by treatment. Total jejunal and mucosal vascularity (mL) were less (P < or = 0.01) in restricted than control ewes. Fetuses from restricted ewes had less BW (P = 0.06), empty carcass weight (P = 0.06), crown-rump length (P = 0.03), liver (P = 0.01), pancreas (P = 0.07), perirenal fat (P = 0.02), small intestine (P = 0.007), and spleen weights (P = 0.03) compared with controls. Fetuses from HSe ewes had heavier (P < or = 0.09) BW, and empty carcass, heart, lung, spleen, total viscera, and large intestine weights compared with ASe ewes. Nutrient restriction resulted in less protein content (mg, P = 0.01) and protein:DNA (P = 0.06) in fetal jejunum. Fetal muscle DNA (nutrition by Se interaction, P = 0.04) concentration was greater (P < 0.05) in restricted ewes fed HSe compared with other treatments. Fetal muscle RNA concentration (P = 0.01) and heart RNA content (P = 0.04) were greater in HSe vs. ASe ewes. These data indicate that maternal dietary Se may alter fetal responses, as noted by greater fetal heart, lung, spleen, and BW.  相似文献   
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We have developed a PCR assay that in a single reaction distinguishes between Leishmania infantum and Leishmania donovani strains on the basis of different size of the amplicon. The targeted intergenic region between putative biopterin transporter and nucleotide binding protein on chromosome 35 is highly variable, species-specific and can be amplified from clinical samples. Based on the assay, five tested Leishmania archibaldi and L. infantun strains from the Sudan and Ethiopia clearly belong to L. donovani, which is in accordance with a recent multifactorial analysis of these strains. The nucleotide sequence reported in this paper has been submitted to the GenBankTM with accession number EU068004.  相似文献   
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