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Feline immunodeficiency virus (FIV) antibodies were detected in 9 of 123 (7.3%) cats. More clinically ill cats had titers to FIV than did healthy cats (15% vs 3.6%). Previous or current illnesses in these FIV-positive cats included urinary bladder disease, anemia, cat-bite abscesses, bacterial infections, bleeding disorders, diabetes mellitus, and chronic respiratory tract disease. All FIV-positive cats were males, with mean age of 6.0 years (range, 1 to 11 years). Half (n = 3) of the clinically ill FIV-positive cats were concurrently seropositive for FeLV antigen. Three of the ill cats were euthanatized or died 1 month after initially testing, whereas the remaining 3 ill cats and the 3 healthy FIV-positive cats were healthy 1 year after initial testing. Antibody titer to FIV persisted in 4 of 5 cats, but serotest results were equivocal in 1 cat evaluated 1 year later.  相似文献   
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Although common among bacteria, lateral gene transfer-the movement of genes between distantly related organisms-is thought to occur only rarely between bacteria and multicellular eukaryotes. However, the presence of endosymbionts, such as Wolbachia pipientis, within some eukaryotic germlines may facilitate bacterial gene transfers to eukaryotic host genomes. We therefore examined host genomes for evidence of gene transfer events from Wolbachia bacteria to their hosts. We found and confirmed transfers into the genomes of four insect and four nematode species that range from nearly the entire Wolbachia genome (>1 megabase) to short (<500 base pairs) insertions. Potential Wolbachia-to-host transfers were also detected computationally in three additional sequenced insect genomes. We also show that some of these inserted Wolbachia genes are transcribed within eukaryotic cells lacking endosymbionts. Therefore, heritable lateral gene transfer occurs into eukaryotic hosts from their prokaryote symbionts, potentially providing a mechanism for acquisition of new genes and functions.  相似文献   
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The wild South American camelids developed a strategy of seasonal reproduction during spring and summer with singleton birth. The photoperiod is one of the factors that may modulate this seasonality where light would be translated into a hormonal signal. This study evaluated the influence of changes in daily light intensity on melatonin concentration in captive guanacos under a long‐day photoperiod (16 hr light/8 hr dark; 33 ‘28′S). Mean melatonin concentration was 28.3 ± 20.3 pg/ml, with a maximum of 52.14 ± 17.19 pg/ml at 23:30 and minimum of 14.29 ± 6.64 pg/ml at 08:30 (p < .001). There was a negative association between light intensity and melatonin concentration (r = ?0.57; p < .001). The results indicate that guanacos respond to variation in daily environmental light with a hormonal response and point to a circannual rhythm as a function of the photoperiod.  相似文献   
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