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71.
72.
Kei Sawata Masahiko Toda Satoru Kanetaka Yoshihisa Sasaki Takuro Hirai 《Journal of Wood Science》2011,57(6):536-541
When it is necessary to repair conventional Japanese wooden houses, the decayed lower parts of columns should be replaced
with new wood material. The bending resistance of columns repaired by four methods and the shear resistance of opening frames
with those repaired columns were investigated in this study. Bending tests of the repaired columns showed differences in initial
bending stiffness and maximum bending moment related to the repair methods and loading direction. Racking tests were conducted
on door opening frames with conventional door head members or upper partial walls sheathed with 12-mmthick plywood. The conventional
frame specimens broke at door head-column joints with no obvious bending deformation of the columns, resulting in little difference
in load-shear deformation curves among the repair methods. The columns of plywood-sheathed specimens, on the other hand, clearly
were bent after the nails at the plywood-to-wood frame joints started to pull off. The load-shear deformation curves of the
plywood-sheathed specimens did not vary regardless of the repair methods when shear deformations were small but were affected
by repair methods as shear deformation increased. 相似文献
73.
Hayashi K Bhandal J Rodriguez CO Kim SY Entwistle R Naydan D Kapatkin A Stover SM 《Veterinary surgery : VS》2011,40(2):198-203
Objective: To (1) determine the microanatomic vascular distribution in ruptured canine cranial cruciate ligaments (CCL) using specific vascular immunohistochemical techniques, and (2) compare vessel density between ruptured and intact canine CCL and between different areas of interest in ruptured CCL using histomorphometric analysis. Study Design: In vitro study. Animals: Dogs (n=41) admitted for surgical treatment of ruptured CCL and 19 dogs euthanatized for nonorthopedic conditions. Methods: Diseased (variable CCL rupture) and intact (normal control) CCL were processed for immunohistochemical staining specific to vessels (factor VIII, laminin). Mean vascular density was assessed and compared in areas of interest (torn end versus remaining core regions of CCL, proximal femoral versus distal tibial core CCL regions). Results: Ruptured CCL was more vascular than intact CCL; however there was no difference in vascular density between the torn end and the remaining core area of the ruptured CCL. Ruptured CCL was vascularized to a greater degree at the proximal portion than the distal portion of the CCL. Partially ruptured CCLs had a higher vessel density than completely ruptured CCLs. Conclusions: Vascular density is increased in diseased CCL compared with intact CCL. It remains to be determined whether this finding is associated with the cause of CCL rupture or is a result of CCL degeneration and rupture. 相似文献
74.
Ito H Takemura N Sonoyama K Kawagishi H Topping DL Conlon MA Morita T 《Journal of agricultural and food chemistry》2011,59(10):5771-5778
This study examined the role of degree of polymerization (DP) of inulin-fructans in modulating the interaction between lactic acid bacteria and IgA cecal secretion. Rats were fed a control diet or a diet containing one of the fructans with different DP. Consuming fructans increased the cecal IgA concentrations in the order DP4 > DP8 > DP16. Cecal lactobacilli counts were higher in DP4, DP8, and DP16, whereas bifidobacteria were higher in DP8, DP16, and DP23. Cecal IgA concentrations were correlated with cecal lactobacilli counts (P < 0.01). DP4, DP8, and DP16, but not DP23, significantly increased IgA-producing plasma cells in the cecal mucosa. IFN-γ and IL-10 production in the cecal CD4(+) T cells was enhanced solely in DP4. The results show that fructans with lower DP enhance cecal IgA secretion and increase the plasma cells and suggest that the increased lactobacilli may contribute to the stimulation of cecal IgA secretion. 相似文献
75.
Konishi K Yonai M Kaneyama K Ito S Matsuda H Yoshioka H Nagai T Imai K 《The Journal of reproduction and development》2011,57(5):572-578
The reproductive ability, milk-producing capacity, survival time and relationships of these parameters with telomere length were investigated in 4 groups of cows produced by somatic cell nuclear transfer (SCNT). Each group was produced using the same donor cells (6 Holstein (1H), 3 Holstein (2H), 4 Jersey (1J) and 5 Japanese Black (1B) cows). As controls, 47 Holstein cows produced by artificial insemination were used. The SCNT cows were artificially inseminated, and multiple deliveries were performed after successive rounds of breeding and conception. No correlation was observed between the telomere length and survival time in the SCNT cows. Causes of death of SCNT cows included accidents, accident-associated infections, inappropriate management, acute mastitis and hypocalcemia. The lifetime productivity of SCNT cows was superior to those of the controls and cell donor cows. All SCNT beef cows with a relatively light burden of lactation remained alive and showed significantly prolonged survival time compared with the cows in the SCNT dairy breeds. These results suggest that the lifetime productivity of SCNT cows was favorable, and their survival time was more strongly influenced by environmental burdens, such as pregnancy, delivery, lactation and feeding management, than by the telomere length. 相似文献
76.
This study was conducted to improve the developmental ability of nuclear transfer (NT) embryos by using blastomeres from in vitro fertilized (IVF) embryos with high quality as donor cells. The IVF embryos selected at the 2-cell stage at 24-h postinsemination (hpi) and again at the ≥8-cell stage at 48 hpi (Selected-IVF-embryos) showed the highest blastocyst formation rate among embryos. When blastomeres from the Selected-IVF-embryos (Selected-NT group) or Nonselected-IVF-embryos (Non-selected-NT group) were used as donor cells for NT, the blastocyst formation rate in the Selected-NT group (25.6%) was significantly higher than that in the Non-selected-NT group (13.5%). When blastomeres from the Selected-IVF-embryos at 108 (contained many cells before cell division) and 126 hpi (contained many cells immediately after cell division) were used as donor cells for NT (108- and 126-NT groups, respectively), the 126-NT group showed a significantly higher blastocyst formation rate (32.1%) than the 108-NT group (16.8%). Embryo transfer of blastocysts in the 126-NT group showed that 11 of 23 recipients became pregnant; nine calves were obtained. For the NT embryos reconstructed using in vivo derived embryos, 9 of 20 recipients became pregnant; seven calves were obtained. These results indicate that the blastocyst formation rate of NT embryos can be improved by using blastomeres from IVF embryos selected at the early developmental stage, especially immediately after cell division, and that the resultant NT embryos have a high developmental ability to progress to term that is comparable to NT embryos reconstructed using in vivo derived embryos. 相似文献
77.
Somfai T Imai K Kaneda M Akagi S Watanabe S Haraguchi S Mizutani E Dang-Nguyen TQ Inaba Y Geshi M Nagai T 《The Journal of reproduction and development》2011,57(6):723-730
Since BSE testing of slaughtered cattle is obligatory in Japan, storage of ovaries at 15-20 C overnight in phosphate buffered saline has become a routine protocol in in vitro production (IVP) of cattle embryos. Ovary storage is known to reduce developmental competence of oocytes; however, its effects on oocyte gene expression have not been clarified yet. This study compared oocytes collected from stored slaughterhouse-derived ovaries with those collected by Ovum Pick-Up (OPU) in terms of the expression of 20 selected genes to determine if ovary storage affects cellular processes at the molecular level. Expression of mRNA in oocytes was assayed before and after in vitro maturation (IVM) by real-time quantitative PCR. Maternal mRNA levels of genes were investigated in 2-cell stage embryos obtained from slaughterhouse oocytes to assess their roles for blastocyst formation. In immature OPU oocytes, genes related to metabolism (GAPDH), transporters (GLUT8, ATP1A1) and stress resistance protein (HSP70) showed significantly higher expression compared with oocytes derived from stored ovaries. During IVM, the expression of GDF9, GLUT8, CTNNB1 and PMSB1 was significantly decreased irrespective of oocyte source. Two-cell stage embryos cleaving at 22-25 h after in vitro fertilization (IVF) showed a significantly higher blastocyst formation rate and ATP1A1 gene expression level compared with those cleaving at 27-30 h after IVF. Our results reveal that storage of ovaries alters mRNA levels in oocytes. Correlation of Na/K ATPase ATP1A1 expression in IVP embryos at the 2-cell and 8-cell stages with their developmental ability to the blastocyst stage may suggest the importance of maternal mRNA of this gene during blastulation in embryos derived from slaughterhouse oocytes. 相似文献
78.
Okada H Iwamaru Y Imamura M Masujin K Matsuura Y Shimizu Y Kasai K Takata M Fukuda S Nikaido S Fujii K Onoe S Mohri S Yokoyama T 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2011,73(11):1465-1471
Bovine spongiform encephalopathy (BSE) is a fatal neurodegenerative disorder of cattle characterized by accumulation of the disease-associated prion protein (PrP(Sc)) in the central nervous system (CNS). The immunohistochemical patterns and distribution of PrP(Sc) were investigated in the CNS, brains, and spinal cords of 7 naturally occurring BSE cases confirmed by the fallen stock surveillance program in Japan. No animals showed characteristic clinical signs of the disease. Coronal slices of 14 different brain areas in each case were immunohistochemically analyzed using an anti-prion protein antibody. Immunolabeled PrP(Sc) deposition was widely observed throughout each brain and spinal cord. Intense PrP(Sc) deposition was greater in the thalamus, brainstem, and spinal cord of the gray matter than in the neocortices. The topographical distribution pattern and severity of PrP(Sc) accumulation were mapped and plotted as immunohistochemical profiles of the different brain areas along the caudal-rostral axis of the brain. The distribution pattern and severity of the immunolabeled PrP(Sc) in the CNS were almost the same among the 7 cases analyzed, suggesting that the naturally occurring cases in this study were at the preclinical stage of the disease. Immunohistochemical mapping of the PrP(Sc) deposits will be used to clarify the different stages of BSE in cattle. 相似文献
79.
Seroepidemiology of Toxoplasma gondii and Neospora caninum in seals around Hokkaido, Japan 总被引:1,自引:0,他引:1
Fujii K Kakumoto C Kobayashi M Saito S Kariya T Watanabe Y Xuan X Igarashi I Suzuki M 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2007,69(4):393-398
Serological analysis was performed to detect Toxoplasma gondii and Neospora caninum infection in seals in Hokkaido. Serum samples were collected from 322 Kuril harbor seals (Phoca vitulina stejnegeri) at Nosappu, Akkeshi and Erimo, from 46 spotted seals (P. largha) at Nosappu, Erimo, Yagishiri Island, Hamamasu and Syakotan, and from 4 ribbon seals (P. fasciata) and a bearded seal (Erignathus barbatus) at Nosappu between 1998 and 2006. Recombinant surface antigen of T. gondii (SAG2t) and N. caninum (NcSAG1t) were used as antigens for ELISA to detect antibodies. Antibodies against SAG2t were detected from 4% of 77 Kuril harbor seals at Nosappu in 2005. Antibodies against NcSAG1t were detected from 2% (1/66) in 2003, 5% (4/79) in 2004 and 10% (8/77) in 2005 of Kuril harbor seals and 11% of 9 spotted seals in 2004 sampled at Nosappu. Eight percent of 12 Kuril harbor seals from Akkeshi and 25% of 4 spotted seals from Erimo in 2005 also contained antibodies against NcSAG1t. These suggest sporadic infection of T. gondii and N. caninum in Kuril harbor seals and spotted seals in Hokkaido. Of the ELISA-positive seals, 2 seals having anti-SAG2t antibodies and 3 seals having anti-NcSAG1t antibodies in 2005 were judged to be juveniles that have no maternal antibodies. These suggest that the protozoan infections have occurred in recent years. Infection of terrestrial protozoa such as T. gondii and N. caninum in seals indicates that the sea environment has been contaminated with protozoa. 相似文献
80.
Gekeler F Gmeiner H Völker M Sachs H Messias A Eule C Bartz-Schmidt KU Zrenner E Shinoda K 《Veterinary ophthalmology》2007,10(3):173-178
OBJECTIVES: To assess the feasibility of optical coherence tomography (OCT) for examining the cat ocular fundus, to provide normative data on retinal thickness in different fundus regions, and to demonstrate selected surgically induced vitreoretinal pathologies in the cat. ANIMAL STUDIED: Forty-five eyes of 28 healthy domestic cats and two eyes of domestic cats that had undergone subretinal implantation surgery for a visual prosthesis were examined. PROCEDURES: An optical coherence tomograph (Zeiss-Humphrey) was used to examine the anesthetized animals. At least five vertical and five horizontal scans in regular distribution were recorded for each cat including (1) the peripapillary region, (2) the area centralis, and (3) the peripheral retina. Thickness was measured manually at five locations in each scan. Retinal thickness was compared in the three above-mentioned fundus regions, between eyes and between vertical and horizontal scans. OCT was additionally performed in animals with retinal detachment and a subretinal visual prosthesis. RESULTS: OCT measurements required only minimal adjustments of human settings and yielded high quality images. In comparison to humans intraretinal layers were more difficult to differentiate. Retinal thickness was highest in the peripapillary region (245 +/- 21 microm), followed by the peripheral retina (204 +/- 11 microm) and the area centralis (182 +/- 11 microm; all P < 0.0001). There was no statistically significant difference between right and left eye or between vertical and horizontal scans. OCT demonstrated retinal detachment, an iatrogenic break and a subretinal prosthetic device in high detail. CONCLUSIONS: Retinal thickness was measurable with high precision; values compare well to older histologic studies. OCT bears significant advantages over histology in enabling one to repeat measurements in living animals and thus allowing longitudinal studies. Various vitreoretinal pathologies common in feline eyes are detectable and quantifiable by OCT. 相似文献