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71.
The present study was undertaken to investigate whether withdrawal of estrogen and progesterone (EP-withdrawal) stimulates prostaglandin F2alpha (PGF2alpha) production through oxygen radical (ROS)-induced NF-kappaB activation in human endometrial stromal cells (ESC). To study the EP-withdrawal, ESC that had been treated with estradiol (E, 10(-8) M) and medroxyprogesterone acetate (MPA, 10(-6) M) for 12 days were then incubated with or without E+MPA for a further 11 days. PGF2alpha concentrations in the medium and cyclooxygenase-2 (COX-2) mRNA levels were significantly increased after EP-withdrawal, while they were unchanged by the continuous treatment with E+MPA. When ESC were incubated with N-acetyl-L-cysteine (Nac, 50 mM), an antioxidant, during EP-withdrawal, Nac blocked the increases in PGF2alpha production and COX-2 mRNA expression caused by EP-withdrawal. Next, we examined whether ROS generated in response to EP-withdrawal acted through NF-kappaB activation. Electrophoretic mobility shift assay revealed that EP-withdrawal caused marked increases in NF-kappaB DNA binding activity, which was completely suppressed by Nac. Furthermore, when ESC were incubated with MG132 (3 microM), which inhibits NF-kappaB activation, during EP-withdrawal, MG132 blocked the increases in PGF2alpha production and COX-2 mRNA expression caused by EP-withdrawal. In conclusion, EP-withdrawal stimulates COX-2 expression and PGF2alpha production through ROS-induced NF-kappaB activation, suggesting a possible mechanism for menstruation.  相似文献   
72.
To examine the differences between juvenile and mature wood, 12 aged sample trees from two areas of Nagano Prefecture were harvested; and the radial development of tracheid length, the ring density, and the relation of the radial growth rate (observed by ring width) with some selected indices of ring structure were investigated. The results proved that the radial variation of tracheid length with ring number can be described by a logarithmic formula, and both plantations reached the demarcation of juvenile and mature wood at age 18. With the segmented regression method, we also analyzed radial variation of mean density and found that the demarcation of juvenile and mature wood was at age 15 for sample trees from Saku and at age 21 for those from Yabuhara. By using the results of estimates from juvenile and mature wood based on ring density, we found that high growth rates resulted when producing lower-density wood during the juvenile period, but these rates did not occur during the mature period. The basic reason for this phenomenon is the variation in patterns of earlywood and latewood in juvenile and mature wood, respectively. This result advised us that when managing plantations of Japanese larch it is necessary to take different measurements at different growth periods.  相似文献   
73.
H5 highly pathogenic avian influenza (HPAI) viruses have spread worldwide, and antigenic variants of different clades have been selected. In this study, the national stockpiled vaccine prepared from A/duck/Hokkaido/Vac-1/2004 (H5N1) strain was evaluated for the protective efficacy against H5N8 HPAI virus isolated in Kumamoto prefecture, Japan, in April 2014. In the challenge test, all of the vaccinated chickens survived without showing any clinical signs and reduced virus shedding. It was concluded that the present stockpiled vaccine was effective against the H5N8 HPAI virus.  相似文献   
74.
This pilot study assessed the efficacy of 2 minimally invasive techniques for proximal interphalangeal (PIP) joint arthrodesis in horses. The PIP joints of both forelimbs (n = 6) were stabilized with locking compression plates (LCP) using a minimally invasive technique (LCP technique). Subsequently, for 1 randomly selected PIP joint of each horse, surgical drilling (SurD) was performed and tissue engineering (TE) was applied (LCP/SurD/TE technique). Minimally invasive PIP joint arthrodesis with LCP demonstrated low postoperative infection rates. Gross and histological evaluations revealed considerable destruction of the articular cartilage in the LCP/SurD/TE-treated joints. In contrast, almost no destruction of the cartilage was observed in the LCP-treated joints. Our results suggest that the LCP technique alone is not sufficient for PIP joint arthrodesis and that the LCP/SurD/TE technique may be useful for PIP joint arthrodesis in horses.  相似文献   
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An 8-month-old common marmoset (Callithrix jacchus) was presented with tic-like symptoms, and a 2-year-old pigmy marmoset (Callithrix pygmaea) was presented with dyspnea and hypersalivation. Both monkeys died within a few days, and necropsies were performed. Histopathological examinations revealed ulcerative stomatitis with epithelial cell swelling and eosinophilic intranuclear inclusion bodies in the oral epithelium of both cases. In the central and peripheral nervous systems, neuronal cell degeneration with intranuclear inclusion bodies was observed. Immunohistochemical examination using anti-herpes simplex virus type 1 antibody revealed virus antigens in both cases. Both animals had been kept as pets with limited exposure to the ambient environment except via their owners. Therefore, herpes simplex virus type-1 was probably acquired from close contact with their owners.  相似文献   
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The occurrence of multiple metabolic and inflammatory diseases in dairy cows is higher during the periparturient period, which may be triggered by bacterial components, but not a viable bacterium. This study aimed to determine the association of endometritis and ovarian follicular cyst (OFC) with mastitis in dairy cows. Ninety-eight Holstein dairy cows were clinically examined for endometritis and OFC approximately 30–50 days after calving. Blood and milk samples were collected for the determination of milk somatic cell count (SCC); milk interleukin-1β (IL-1β), tumor necrosis factor-α (TNFα), and interleukin-8 (IL-8) concentrations; and plasma haptoglobin (Hp) and lipopolysaccharide-binding protein (LBP) concentrations. Of the 98 dairy cows included in this study, 12 were diagnosed with endometritis and 37 cows were identified as OFC-positive, whereas the remaining 49 cows were healthy (without endometritis or OFC). The average and maximum SCCs and plasma Hp and LBP concentrations were not significantly different between the healthy cows and those with endometritis or OFC. However, when the maximum SCC was classified as <300, 300–1,000, or >1,000 × 103 cells/ml, the percentage of cows with the maximum SCC <300 × 103 cells/ml was significantly lower in the endometritis and OFC-positive groups than in the healthy group. These results suggested that cows with endometritis and OFC during the postpartum period exhibit high SCC, indicating that some bacterial components can be transferred between organs.  相似文献   
80.
Nasal lymphoma (NL) is the most common nasal tumor in cats, and radiotherapy, chemotherapy, or a combination of these treatments have been described as the treatment for this disease. However, the previous studies included various machines and protocols of radiotherapy. Therefore, we aimed to retrospectively compare the prognosis among cases treated with palliative hypofractionated radiotherapy, chemotherapy, and a combination of them with united machine and protocol of radiotherapy. When compared overall survival and progression free survival, there was no significant difference among these three groups. The data of this study suggested that similar efficacy could be achieved by palliative hypofractionated radiotherapy, chemotherapy, or a combination of them.  相似文献   
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