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81.
This study deals with the effects of carbon dioxide (CO2)-air concentration in the rapid curing method on the properties of cement-bonded particleboard manufactured using conventional cold pressing as the setting method. The hydration of cement was examined using X-ray diffractometry, thermal gravimetry, and scanning electron microscopy. The results are as follows: (1) The properties of CO2-cured boards improved with increasing CO2 concentration. When 10% or 20% CO2 was applied for 10 min of curing time, the properties of the CO2-cured boards were comparable to those obtained by conventional 2-week curing. (2) The hydration process of cement could be accelerated within several minutes using CO2 curing, even with a low concentration of 10%–20% CO2; a reduction in calcium hydroxide was observed followed by rapid formation of calcium carbonate.  相似文献   
82.
The extractives of shirakamba (Betula platyphylla Sukatchev var.japonica Hara) leaves were investigated. Two lignan glycosides were isolated, and their structures were elucidated to be 1-(4-hydroxy-3-methoxyphenyl)-2-[1-(3--l-rhamnopyranosyloxypropyl)-3-hydroxyphenoxy]-1,3-propanediol (I) and a new 2,3-dihydro-2-arylbenzofuran configuration neolignan,cis-2,3-dihydro-2-(4--l-rhamnopyranosyloxy-3-methoxyphenyl)-3-hydroxymethyl-7-hydroxy-5-benzofuranpropanol (II). These neolignan rhamnosides were newly found in shirakamba.  相似文献   
83.
Although the causes have not been specified yet, wild populations of northern fur seals (Callorhinus ursinus) have been decreasing, which is why conservation techniques such as captive breeding and health maintenance should be established. Hematological parameters can be used to maintain the health status of northern fur seals kept in captivity for artificial reproduction and public education. Year-round fluctuations of blood parameters have not been examined for northern fur seals due to the difficulties in obtaining serial blood samples from wild animals during the oceanic migration period from late autumn to spring. In this study, blood samples were collected from four captive northern fur seals and analyzed monthly for more than three years to clarify the seasonal fluctuation patterns in 14 hematological parameters. Many hematological parameters seemed to be seasonal patterns: summer–autumn and winter–spring; leukocyte-related parameters were higher in summer and autumn than in winter and spring; erythrocyte-related parameters were lower in summer and autumn than in winter and spring. Significant seasonal differences in nine of the 14 parameters were observed using a generalized linear mixed model (GLMM) analysis. These results have improved our understanding of the seasonal patterns of hematological characteristics in the northern fur seal and can contribute to the health care of protected or captive northern fur seals.  相似文献   
84.
Immunohistochemical investigations of the expression of surfactant protein A (SP-A) and surfactant protein D (SP-D) in the uterine and placental tissues of 13 pregnant mares were performed using anti-horse monoclonal primary antibodies. Strong positive reactions for both SP-A and SP-D were observed in the trophoblasts in the microcotyledons of the placentae at 182 to 314 days of gestation; in uterine glandular epithelial cells, faint-to-weak reactions were observed during gestation. This study describes, for the first time, the changes in the SP-A and SP-D expression levels in the endometrium of mares during gestation; the SP-A and SP-D expression levels increased after the second trimester of gestation.  相似文献   
85.
Prevalence of equine gastric ulcer syndrome in 85 young Thoroughbreds was investigated. The presence of gastric ulcers was confirmed in 27.1% (23/85) of the horses by endoscopic examination. Sixty-two horses without gastric ulcers were allocated randomly to either the treated group (31 horses) or sham-dosed control group (31 horses) in order to investigate the efficacy of omeprazole oral paste in the prevention of gastric ulcers. At the second endoscopic examination conducted after 28 days of administration, only 1 horse in the treated group developed gastric ulcers, while 12 horses developed gastric ulcers in the control group. Based on these data, the efficacy of omeprazole in prevention of equine gastric ulcers in young Thoroughbreds during the training period was confirmed.  相似文献   
86.
A series of in sacco and in vitro studies were carried out to evaluate bean husks for activation of fibrolytic rumen bacteria and rice straw digestion. First, lablab bean husk, chickpea husk and rice straw were suspended in the rumen of sheep to analyze the bacterial consortium developed on each fiber source. Known members of fiber‐associating bacteria were found on both lablab bean husk and rice straw, but some of these bacteria were lacking on chickpea husk. Second, a pure culture study was carried out using six strains of Fibrobacter succinogenes. Both husks stimulated the growth of all tested strains, including a strain that did not grow on rice straw. The strain OS128 that showed the highest growth on rice straw displayed even higher growth on lablab bean husk without a time lag. Finally, two‐step incubations were carried out to determine whether prior incubation of rumen fluid with husks stimulates subsequent rice straw digestion. Higher digestibility of rice straw was recorded in the second‐round incubation following the first incubation with bean husks. These results suggest that the tested bean husks improve the digestion of rice straw by activating fibrolytic F. succinogenes and other associated bacteria.  相似文献   
87.
88.
To understand roles of interleukin 6 (IL-6) family cytokines for pregnancy in mice, localization of IL-6 receptor (IL-6R) mRNA was investigated in non- and early pregnant uteri by in situ hybridization. IL-6R mRNA was expressed in all non-pregnant uteri and in pregnant uteri from the third day (Day 3) to the sixth day of pregnancy (Day 6; the day of plug = Day 1). IL-6R mRNA signals were detected in non-pregnant mice in the luminal and glandular epithelium. Signal strength varied according to the sexual cycle. There was no correlation between the signal strength of the IL-6R mRNA and the serum concentrations of progesterone and 17beta-estradiol, which show a monophasic rise in the non-pregnant sexual cycle. In pregnant mice, slight signals were detectable in the luminal and glandular epithelium on Day 3. IL-6R mRNA messages increased with progression towards Day 4, however, localization changed drastically on Day 5. Stromal cells abruptly expressed their mRNA on Day 5, and these cells strongly expressed it on Day 6. The function of IL-6R in the luminal and glandular epithelium might be different from that in the stroma during the implantation period. In addition, few signals were identified in the stromal cells adjacent to the luminal epithelium on Day 6. This suggests that there are two types of stromal cells on Day 6 in mice.  相似文献   
89.
Equine coronavirus (ECoV) was first isolated from a diarrheic foal and was found genetically similar to group II coronaviruses. However, its pathological characteristics were not adequately investigated. In our preliminary in vitro investigation, ECoV-induced cell death was observed in bovine kidney-derived MDBK cells. Based on this finding, we investigated whether the ECoV-induced CPE was apoptosis. Following ECoV infection, MDBK cells showed morphological changes such as cell rounding and detachment from the culture surface. Moreover, syncytium formation was observed as the other type of cytopathic effect in ECoV infection. Morphologic and biochemical features of apoptosis, such as nuclear fragmentation and DNA ladder formation, were also detected in ECoV-infected cells. Moreover, as is commonly observed in coronavirus infection in other animals, the activities of effecter caspases – caspase-3/7 – and initiator caspases – caspase-8 and caspase-9 – that are representative factors in the death receptor-mediated apoptotic pathway and mitochondrial apoptotic pathway, respectively, were increased in ECoV-infected MDBK cells. Therefore, it was suggested that ECoV can induce apoptosis in MDBK cells via a caspase-dependent pathway. Apoptotic death of infected cells is detrimental because it causes cell and tissue destruction and inflammatory responses. Although the pathological characteristics of ECoV are largely unknown, apoptosis may be the pathological basis of lesions of the digestive system in ECoV infection.  相似文献   
90.
Developing lymphoid tissues of bovine fetuses ranging from 70 to 270 days of fetal age were examined by histological and immunohistochemical procedures. In the peripheral blood, surface membrane immunoglobulin bearing cells (B-lymphocytes) and sheep red blood cell rosette forming cells (T-lymphocytes) had already appeared by 70 days of fetal age. In the lymph nodes intracytoplasmic IgM positive cells appeared at 90 days of fetal age. The cells positive for IgG appeared at 150 days of fetal age and IgA positive cells appeared at 180 days of fetal age. The spleen contained intracytoplasmic immunoglobulin positive cells at almost the same time as those in the lymph nodes. In the ileocecal region, IgM positive cells and IgG positive cells were present at 180 days of fetal age and IgA positive cells were present at 210 days of fetal age. The tonsils contained IgM positive cells and IgG positive cells at 240 days of fetal age. In the thymus, terminal deoxynucleotidyl transferase positive cells appeared at 90 days of fetal age.  相似文献   
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