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Biopsies of skin from a 2-year-old heifer with spontaneously regressing dermal leukosis were examined. The heifer was not infected with bovine leukemia virus and was negative for tumor-associated antigens of enzootic bovine lymphosarcoma. By hematological standards for bovine leukemia, the heifer was positive at about 60 days post-occurrence of the disease (POD). At 53 days POD, lymphoblastic neoplastic cells in the dermis reacted with anti-T lymphocyte monoclonal antibody by the avidin biotin peroxidase complex method. The cells had intracytoplasmic clustered dense bodies under electron microscopy. From 53 to 83 days POD, figures of the transepithelial elimination (TE) against neoplastic cells and perivascular infiltration of small lymphocytes were in the dermis. Small lymphocytes reacted with anti-T lymphocyte monoclonal antibody. At necropsy there were no neoplastic lesions; there were flat lymph node-like tissues in the subcutis. Many germinal centers were seen in the lymphatic organs. Blood lymphocytes at 46 days POD were stimulated by phytohemagglutinin-P and concanavalin A. Sera, taken until 75 days POD and at necropsy, showed an inhibitory effect on mitogen-induced blastogenesis of normal bovine lymphocytes. These results suggested the existence of a spontaneous regressive mechanism against neoplastic lesions by TE and tumor immunity.  相似文献   
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Tubulointerstitial nephritis antigen-like 1 (Tinagl1, also known as adrenocortical zonation factor 1 [AZ-1] or lipocalin 7) is a matricellular protein. Previously, we demonstrated that Tinagl1 expression was restricted to extraembryonic regions during the postimplantation period and detected marked expression in mouse Reichert’s membranes. In uteri, Tinagl1 is markedly expressed in the decidual endometrium during the postimplantation period, suggesting that it plays a physical and physiological role in embryo development and/or decidualization of the uterine endometrium during pregnancy. In the present study, in order to determine the role of Tinagl1 during embryonic development and pregnancy, we generated Tinagl1-deficient mice. Although Tinagl1–/– embryos were not lethal during development to term, homologous matings of Tinagl1–/– females and Tinagl1–/– males showed impaired fertility during pregnancy, including failure to carry pregnancy to term and perinatal lethality. To examine ovarian function, ovulation was induced with equine chorionic gonadotropin (eCG) and human chorionic gonadotropin (hCG); the number of ovulated oocytes did not differ between Tinagl1–/– and Tinagl1flox/flox. In vitro fertilization followed by embryo culture also demonstrated the normal developmental potential of Tinagl1-null embryos during the preimplantation period. Our results demonstrate that Tinagl1 deficiency affects female mice and results in subfertility phenotypes, and they suggest that although the potential of Tinagl1–/– oocytes is normal, Tinagl1 is related to fertility in adult females but is not essential for either fertilization or preimplantation development in vitro.  相似文献   
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We observed a significant difference in the organic acid profile of diarrheal feces between pigs infected with and free from pathogenic spirochetes. Diarrhea and loose feces were collected from growing pigs, held at 15 different commercial farms. A total of 106 samples were measured for organic acid concentration by HPLC and were checked for the presence of B. hyodysenteriae and B. pilosicoli by PCR. B. hyodysenteriae was detected in 3 samples collected from one farm. B. pilosicoli was detected in 5 samples collected from another farm. Lower concentrations of iso-butyrate and iso-valerate were likely associated with development of pathogenic spirochete infection.  相似文献   
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Previous our studies have shown that CD44, the principal receptor for hyaluronan, is present on cumulus cells during oocyte maturation. Although hyaluronan-CD44 interaction has been implicated in cumulus expansion and/or oocyte maturation, the full significance of CD44 remains unknown. The objective of the present study was to further investigate the role of CD44 in cumulus expansion and oocyte maturation in pigs. We demonstrate here in that CD44 has a key role in oocyte maturation but not in cumulus expansion. Previous studies have reported the physiological significance of cumulus expansion in oocyte maturation. However, our results suggest that cumulus expansion is a necessary condition for oocyte maturation, but that it is not sufficient on its own. Furthermore, western blot analysis demonstrated that the CD44 of the in vitro-matured cumulus-oocyte complexes (COCs) had a larger molecular weight and more terminal sialic acid, which has been proven to inhibit the hyaluronan-binding ability of the receptor, than the CD44 of the in vivo-matured COCs, indicating that the hyaluronan-CD44 interactions during in vitro maturation might be insufficient compared with those in vivo. The insufficient interactions of hyaluronan-CD44 during in vitro maturation may cause the inferior capacity of fertilization and development of oocytes matured in vitro.  相似文献   
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We previously reported that calcium (Ca) nutrition in tomato (Lycopersicon esculentum Mill.) significantly affected the resistance to bacterial wilt caused by Ralstonia solanacearum Smith. To elucidate the mechanisms underlying the Ca-dependent resistance, the effect of the Ca concentration in the nutrient solution applied before and after inoculation with the pathogen on the resistance of tomato seedlings to bacterial wilt was studied. One week before inoculation, seedlings were transferred to nutrient solutions containing Ca at concentrations of 0.4, 4.4, or 20.4 mM. Soon after inoculation, the seedlings that were treated with each concentration of Ca before inoculation were transferred to solutions containing the same three concentrations of Ca. Although the disease development was not affected by the concentration of Ca in the solution before inoculation, a higher concentration of Ca after inoculation reduced the disease severity. This result suggests that the concentration of Ca in the host, especially in the cell walls, before infection may not be directly involved in the Ca-dependent resistance of tomato seedlings to bacterial wilt.  相似文献   
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To clarify the effects of temperature on the recruitment of chub mackerel (Scomber japonicus) in the North Pacific, we investigated the influence of winter surface temperature (WST) on spawners at the time of maturity around the spawning grounds and the influence of ambient spring temperature on larvae using estimated temperature (ET) obtained from particle tracking experiments. We found a significant positive correlation between ET approximately 10 days following hatching and the recruitment per spawning stock biomass (RPS) after 2000. The closer (more meandering) the Kuroshio Current (KC) axis was in relation to the spawning ground, the higher (lower) the spring surface temperature and the higher (lower) RPS was in the spawning ground. In contrast, WST inside KC near the maturity/spawning ground was significantly negatively correlated with RPS. A significant negative correlation between the temperatures in winter and spring was detected in the area after 2000, when the conditions of the Pacific decadal oscillation index and the stability of the Kuroshio Extension were synchronous, indicating that KC shifted northward during this time. The reversed temperature pattern was consistent with the winter–spring movement of KC axis in the offshore direction and was correlated with the winter–spring difference in the intensity of the Aleutian low. These results suggest that the annual variation in chub mackerel recruitment after 2000 was strongly affected by the combined effects of ambient temperature because of the reversal of conditions that occurred between winter and spring around the maturity/spawning ground, which was related to the KC path.  相似文献   
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OBJECTIVE: To investigate the effects of long-term administration of recombinant bovine tumor necrosis factor-alpha (rbTNF) on plasma glucose and growth hormone concentrations, and to determine whether treatment with rbTNF causes insulin resistance in steers. ANIMALS: 5 steers treated with rbTNF and 5 steers treated with saline (0.9% NaCl) solution (control). PROCEDURES: In experiment 1, rbTNF (5.0 microg/kg of body weight) or saline solution (5 ml) was administered SC daily for 12 days. Blood samples were obtained before treatment, and plasma was harvested for determination of glucose, insulin, and growth hormone (GH) concentrations. In experiment 2, insulin, glucose, or growth hormone-releasing hormone (GHRH) was administered IV on days 7, 9, and 11, respectively, after initiation of rbTNF or saline treatment in experiment 1. Plasma glucose and insulin concentrations were measured before and at various times for 4 hours after insulin or glucose administration. Plasma GH concentrations were measured at various times for 3 hours after GHRH administration. RESULTS: In experiment 1, administration of rbTNF resulted in hyperinsulinemia without hypoglycemia and decreased plasma GH concentrations. In experiment 2, plasma glucose concentrations were higher in steers treated with rbTNF and insulin than in controls. Plasma GH concentrations were lower in steers treated with rbTNF and GHRH than in controls. CONCLUSIONS AND CLINICAL RELEVANCE: Prolonged treatment with rbTNF induced insulin resistance and inhibited GHRH-stimulated release of GH in steers. Results indicate that rbTNF is a proximal mediator of insulin resistance and inhibits release of GH during periods of endotoxemia or infection.  相似文献   
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