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In canine lymphoma, drug resistance is the major factor hindering treatment. In this study, we performed immunohistochemical examination of P-glycoprotein (P-gp) and breast cancer resistance protein (BCRP), which are considered as transporters related to multidrug resistance in three recurrent canine lymphomas. All cases were negative for both transporters before anticancer drug administration, but became positive after this administration. The expression was confirmed in capillary endothelial cells, such as in brain capillaries acting as the blood-brain barrier (BBB). It is suggested that both transporters expressed on capillary endothelial cells in lymphoma tissue may inhibit the spread of anticancer drugs into tumor tissues from blood, the same as the BBB. Therefore, capillary endothelial cells could act as a blood-tumor barrier, which might be involved in drug resistance in canine lymphoma.  相似文献   
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The endometrial epidermal growth factor (EGF) profile is an indicator of uterine function and fertility in cattle. The present study aimed to investigate the effects of heat stress on the endometrial EGF profile and fertility in lactating Holstein cows. The endometrial EGF profiles of 365 cows in the Hokkaido and Kyushu regions were examined between June and September (heat stress period, n = 211) and between October and January (control period, n = 154). EGF profiles were investigated using uterine endometrial tissues obtained by biopsy 3 days after estrus (Day 3). The proportion of cows with an altered EGF profile was higher between June and September than between October and January (41.2 vs. 16.2%, P < 0.05). The effects of rectal temperature on Days 0 and 3 on the endometrial EGF profile were also assessed in cows (n = 79) between June and September in the Kyushu region. A single embryo was transferred to cow on Day 7 to evaluate fertility (n = 67). Regardless of the rectal temperature on Day 3, the proportion of cows with an altered EGF profile was higher (64.1 vs. 30.0%, P < 0.05) and the pregnancy rate after embryo transfer (ET) was lower (26.7 vs. 51.4%, P < 0.05) in cows with a rectal temperature ≥ 39.5°C on Day 0 than in cows with a rectal temperature < 39.5°C on Day 0. The present results indicate that alterations in the endometrial EGF profile induced by an elevated body temperature on Day 0 contributed to reductions in fertility in lactating dairy cows during the heat stress period.  相似文献   
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Tris(1,3-dichloro-2-propyl) phosphate (TDCIPP) is widely used as a flame retardant and is known to exhibit anti-androgenic effects in vitro and in vivo. To assess the reproductive toxicity potency of TDCIPP, we investigated the effects of 7 days of TDCIPP oral administration on epididymal sperm motion and concentration in adult male Wistar–Imamichi rats. Thirty-five days after the final administration, sperm parameters were evaluated by computer-assisted sperm analysis. Results showed that sperm swimming progression and vigor and sperm concentration in TDCIPP-treated rats were unexpectedly higher than those in control rats. TDCIPP did not significantly affect the percentage of motile sperms or sperm swimming pattern. These results contribute to the understanding of the biological effects of TDCIPP.  相似文献   
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When detached broad bean leaves were preinoculated with virulent strain B304 of Botrytis cinerea 24 h before a challenge inoculation with strain B304, lesion formation by B304 was significantly inhibited in red light but not in the dark. In leaves that were preinoculated with avirulent strain 021 and then challenged by B304, however, lesion formation was not inhibited even under red light. Such differences in lesion formation after the challenge inoculation with an avirulent strain were also observed with lesions caused by Alternaria alternata, a nonpathogen of broad bean and by avirulent strain 021R in the presence of germination fluid from spores of strains B304 and 021R. These results suggest the possibility that virulent B. cinerea produced a suppressor involved in induced susceptibility and an elicitor involved in resistance induced by red light during spore germination.  相似文献   
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In vitro cell culture is a convenient tool for studying cellular mechanisms. In the present study, production of matrix-metalloproteinases (MMPs) in bovine endometrial (containing both epithelial and stromal cells) monolayer cells was examined. Blastocysts attached to the endometrial cells in a monolayer culture were examined for their effects on MMP-2 production. Initial attachment of blastocysts to the monolayer inhibited MMP-2 production by endometrial cells. But once trophoblast cells began to migrate into the endometrial cell layer, MMP-2 production increased, and at the same time MMP-9 production also became evident in the medium. In order to understand how blastocysts affected MMP-2 production, we examined the effect of progesterone, estradiol, insulin-like growth factors (IGFs), tumor necrosis factors (TNFs), and interferon-tau (IFN-tau) supplementation. It was IFN-tau that inhibited the production of MMP-2. In addition, progesterone at a lower dose appeared to inhibit MMP-2 production. Both TNF-alpha and TNF-beta strongly stimulated the production of MMP-2 and MMP-9, whereas IGFs had no effect. Based on these findings, it appears that conceptus has the capacity to inhibit MMP activity.  相似文献   
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The development of a PCR assay based on the 16S ribosomal RNA gene (rDNA) sequence was carried out for the identification of Staphylococcus intermedius. Sixty-six strains of S. intermedius, 70 of Staphylococcus aureus and 2 of Staphylococcus hyicus were examined for the assay. The 16S rDNA, of which the PCR target fragment makes up 901 bp corresponding to the sequence data of the gene, was detected in all strains of S. intermedius, but it was not detected in any strains of either S. aureus or S. hyicus. These results suggest that the PCR allows a simple and precise identification of S. intermedius.  相似文献   
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From April 1999 to December 2000, a survey was made on the distribution of Staphylococcus species on the skin of 7 kinds of animals and humans. Staphylococci were isolated from 12 (100%) of 12 pigs, 17 (89.5%) of 19 horses, 30 (100%) of 30 cows, 73 (90.1%) of 81 chickens, 10 (40%) of 25 dogs, 23 (76.7%) of 30 laboratory mice, 20 (52.6%) of 38 pigeons, and 80 (88.9%) of 90 human beings. The predominant staphylococci isolated from a variety of animal species were novobiocin-resistant species, S. xylosus and S. sciuri regardless of the animal host species. The novobiocin-resistant species including S. xylosus and S. sciuri were only occasionally isolated from human skin. The predominant staphylococci found on human skin were novobiocin-sensitive species, S. epidermidis (63.8%), followed by S. warneri (28.8%) and S. hominis (13.8%). The results suggest that the staphylococcal flora inhabiting animal skin are different from those of human skin in regard to the predominant species isolated. In this study, we used pulsed-field gel electrophoresis to examine the chromosomal polymorphisms of S. epidermidis isolated most frequently from human skin. Strains of S. epidermidis showed the greatest genomic diversity in their fragment patterns.  相似文献   
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The prevalence of staphylococci that harbor the mecA gene responsible for methicillin resistance was examined in healthy breeding mares. Staphylococci often cause diseases of horses such as metritis, keratitis, and abscess. Methicillin-resistant staphylococci would make antibiotic treatments ineffective, so it may be significant to know the distribution of mecA-harboring staphylococci in mares. Isolation of mecA-harboring staphylococci was achieved from nares and pasterns of 100 mares in Hokkaido, Japan. From 13% of the mares, mecA-harboring staphylococci, including 15 isolates of Staphylococcus sciuri and 3 of Staphylococcus lentus, were isolated. Isolates of S. sciuri were found to be genetically polyclonal by pulsed-field gel electrophoresis. These isolates produced no PCase and showed low or no resistance to beta-lactam and other classes of antibiotics. Distribution of staphylococcal species and levels of antibiotic resistance were found to be different between isolates from the present mares and those previously reported from riding-horses. Antibiotic pressure may lead to these differences. In addition, it appears that mecA-harboring S. sciuri may be native to horses.  相似文献   
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