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11.
Macrophage colony-stimulating factor (M-CSF) is a hemopoietic cytokine with a primary role in placental physiology. Gene expression of M-CSF in the bovine endometrium shows a temporal upward trend during early and mid pregnancy. This study determined the plasma M-CSF levels during pregnancy using ELISA. In experiment 1, to investigate the relationship between the concentration of M-CSF in peripheral blood and pregnancy, the plasma M-CSF levels were determined in 125 pregnant and 21 non-pregnant Japanese Black cows. The pregnant animals were divided into nine groups based on the month of pregnancy. An ELISA for bovine M-CSF established previously was used according to the authors' instructions. In experiment 2, the plasma M-CSF level was determined to investigate the temporal changes in its concentration in the peripheral blood during pregnancy. In experiment 1, the plasma M-CSF level varied from month to month during pregnancy; the mean level in the first-month of pregnancy was significantly higher than those in the third and last months of pregnancy and non-pregnancy (P<0.05). In experiment 2, the plasma M-CSF level varied with the day of pregnancy (P<0.05). The mean level of plasma M-CSF decreased gradually until 6 weeks of pregnancy; it appeared to increase during weeks 7-9, then varied with several small peaks until 27 weeks of pregnancy and finally decreased gradually until parturition. These results suggest that the plasma M-CSF level may be related to changes in the uterus and placenta as pregnancy progresses.  相似文献   
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Reasons for performing study: Measurement of cartilage oligomeric matrix protein (COMP) in serum has potential for diagnosis of equine osteoarthritis (OA), but clinical use is currently limited by the lack of specificity of an inhibition ELISA as well as by baseline increases due to exercise. Improved methods for ELISA with increased antigen specificity and sensitivity are therefore required for reliable measurement. Hypothesis: Measurement of the serum level of COMP by sandwich ELISA allows identification of horses with OA. Methods: New monoclonal antibodies (mAbs) were elicited against equine cartilage COMP, their epitopes were determined and a sandwich ELISA was developed. The concentrations of COMP in synovial fluid (SF; n = 100) and sera (n = 100) from OA cases were measured by sandwich ELISA as well as by inhibition ELISA and compared with concentrations in normal joints (n = 95) and horses (n = 50). Results: Immunoblots of enzymatically cleaved COMP showed that the new mAbs recognised different epitopes located on a 20 kDa fragment between K63 and K238 of the EGF‐like repeats. Inhibition ELISA with any mAb detected significantly increased levels of COMP in OA SF compared with normal SF, whereas no significant difference was detected between serum levels of COMP in OA and normal horses. Conversely, sandwich ELISA with the combination of unlabelled 2A11 × biotinylated 11F10 mAbs detected a significant increase in COMP levels in both serum and SF from OA cases compared with levels in normal animals. Conclusions and potential relevance: Measurement of serum COMP with sandwich ELISA may be useful in identifying horses with OA.  相似文献   
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The use of adhesive joints is gradually increasing, especially those with glued-in steel rods (GIRs). There are, however, some problems with the design methods when used for moment-transmitting applications. In this article, design methods for GIRs and cross-lapped glued joints (CLJs) are proposed. For CLJs, we made a hypothesis that both rotational deformation of CLJ and stress of the glue line occurred with bending and shearing deformation of the timber. Using this hypothesis and Kelvin’s theorem, a mechanical model of CLJ is proposed. For GIRs, the axial stress component of the rod and the lateral stress component of the rod were taken into account using the theory of a beam on an elastic foundation. From the comparisons between calculations and experimental results, it was recognized that the stiffness and strength of CLJs and GIRs could be predicted precisely using our proposed models.  相似文献   
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Taphrina wiesneri, the pathogen of witches’ broom of cherry, is highly pathogenic to Cerasus × yedoensis, the most widely planted ornamental cherry species in Japan. For adequate control of this disease, it is necessary to understand the life history of T. wiesneri. However, sites inhabited by T. wiesneri within infected trees are little understood, except during flowering and leafing periods in spring. Therefore, we attempted to detect the location of T. wiesneri in shoots of witches’ broom before flowering and leafing in spring using PCR with a T. wiesneri-specific primer pair that was designed from 69 sequences in rDNA-internal transcribed spacer region of 32 Taphrina species. DNA extracted from symptomatic and asymptomatic C. × yedoensis sampled before leafing was amplified by PCR. T. wiesneri was detected in every bud and 5-mm stem segment of symptomatic shoots, except for one stem segment, and locally inside buds and the inner bark of stem segments. These results indicate that T. wiesneri overwinters inside symptomatic shoots. Fungal hyphae were observed with an epifluorescence microscope in intercellular spaces of young leaves in symptomatic buds but not in asymptomatic ones in thin sections stained with fluorescein-isothiocyanate-conjugated concanavalin A. This observation supports the results of PCR detection.  相似文献   
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Equine arteritis virus (EAV) was readily isolated in RK-13 cell monolayers by plaque assay from seminal plasma of experimental carrier stallions when they contained high titers of virus regardless of the presence of non-viral cytotoxicity in the seminal plasma. The cytotoxicity interfered with virus isolation from seminal plasma which contained virus at titers less than 10 PFU/ml. However, it was possible to detect the virus in seminal plasma pretreated with PEG (#6000). EAV was consistently identified by RT-PCR from crude seminal plasma which contained virus at titers of more than 10(2.7) PFU/ml. In vitro detection of EAV by virus isolation supplemented with RT-PCR using seminal plasma was proved to be an effective alternative to the standard test mating as a diagnostic method for carrier stallions.  相似文献   
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Compressed wooden plates and dowels were used to connect members in post-and-beam structures as a substitute for a steel fastener. In order to take advantage of the characteristic properties of compressed wood and to achieve optimum joint performance, two compressed wooden plates were used in each joint to give multiple shear planes for each compressed wooden dowel. Consequently, this type of joint showed very good properties in pull-out and momen-trotation performance, and its engineering design could be further optimized. This joint is expected to be introduced to many kinds of structural systems, including long-span frame structures made of domestic timber found in Japanese residential houses.  相似文献   
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A wooden lattice floor with high stiffness and damping capacity has been developed to solve noise problems in wooden apartment houses. The lattice floor consisted of Douglas fir glulam beams with inserted steel plate joints and drift pins. To examine the structural performance of the floor, dynamic excitation and static loading tests were conducted on the full size floor. The first and second order resonance frequencies of the floor were 13.5Hz and 27.0Hz, respectively. These frequencies are similar to the peak frequency of a conventional wooden floor and the combined floor fabricated from glued laminated timber and iron. The maximum static load of the floor was 127kN. The apparent flexural rigidity was less than half the value of several floors studied in the past. However, it is considered that the stiffness is improved by constructing panels and this floor has almost equivalent performance. Relative deflection was not affected by the loading history.Part of this study was presented at the International Wood Engineering Conference, New Orleans, October 1996.  相似文献   
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