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541.
A diagnosis of plasma cell myeloma was made in a 6-year-old Holstein cow that showed continuous nosebleed, progressing emaciation, and hyperglobulinemia. Necropsy revealed enlargement of the caudal mesenteric lymph nodes. Lymph nodes and spleen were infiltrated by neoplastic plasma cells. Renal lymph nodes, bone marrow, and kidneys also were affected. Amyloid-like material that was negative for Congo red was present in most of the affected lymph nodes. Congo red-positive amyloid material was noted in spleen, kidneys, liver, and adrenal glands. Neoplastic plasma cells exhibited immunohistochemical reactions for lambda-light chain and 3 classes of heavy chain but not for kappa-light chain. Nonamyloid deposits were labeled with antisera against lambda-light chain and heavy chains. Plasmacytoid cells, which stained positively for IgG, IgM, or IgA, were intermingled in all lesions. Production of 3 types of immunoglobulins may be caused by heavy-chain class switching, constantly occurring in certain proportions.  相似文献   
542.
To clarify the genetic influence of mycoplasmal pneumonia of swine (MPS) lesion‐selected Landrace (La) on MPS resistance and immune characteristics in three‐way crossbred pigs (LaWaDa), the LaWaDa pigs were compared with the non‐selected crossbred (LbWbDb) and purebred (La) pigs. The MPS lesion score in the three lines was as follows: La line < LaWaDa line < LbWbDb line, with significant differences among the lines. The proportions of myeloid cells and T cells were lower and higher, respectively, in the LaWaDa pigs compared with those in the other two lines. Messenger RNA (mRNA) expression of interleukin (IL)‐6, IL‐10, transforming growth factor‐β, and interferon‐γ in peripheral blood was significantly increased after vaccination in the La and LaWaDa lines. IL‐4 mRNA expression in the LaWaDa line was intermediate to the La and LbWbDb lines. Furthermore, principal component analysis for immune traits and MPS lesions was executed to clarify the characteristics of each pig line. These findings suggest that the immune responses in the three pig lines are genetically distinct and that MPS resistance and some immunity characteristics from the La line were transmitted to the three‐way crossbred pigs.  相似文献   
543.
Many bony fish type I collagens have a characteristic third chain designated as α3(I). However, much less is known about the primary structure and distinction of the proα(I) chains. Their cDNAs were cloned by RT-PCR from the muscle tissue of Japanese eel, Anguilla japonica. Three cDNAs coding for the triple-helical domain of fibrillar collagen were identified as proα1(I), proα2(I) and proα3(I) chains by sequencing selected tryptic peptides isolated from eel type I collagen subunit chains, α1(I), α2(I) and α3(I). Eel proα3(I) had high amino acid sequence identity (81 %) to its proα1(I). The distribution of seven Cys residues in the C-propeptide of proα3(I) was identical to that of proα1(I). There was a third Cys residue at the 1,268th position from the N-terminus in proα1(I), though a supposed Cys residue at the 1,264th position in proα3(I) was replaced by a Ser residue. Similar replacement has been observed in the proα3(I) chains of trout and zebrafish. These combined results suggest that replacement of the Cys residue allows for the identification of fish collagen proα(I) previously not identified as proα3(I).  相似文献   
544.
Distributions of eggs, larvae and juveniles of Pacific herring Clupea pallasii were surveyed in Lake Akkeshi and the connecting Akkeshi Bay on the Pacific coast of eastern Hokkaido. Eggs were found attached to seagrasses and seaweeds in the densely vegetated eastern inner lake. Larvae (7.1–34.9 mm total length) were distributed in the less densely vegetated inner lake during April and June. Juveniles (35.0–89.6 mm) were collected in the central and western parts of the lake. The sites containing juveniles were less densely vegetated with water temperatures lower than 20 °C from June to August. When the water temperature of the entire lake rose to 20 °C in late summer, juveniles appeared to move from the lake to the bottom layer of Akkeshi Bay, which has lower temperatures. Thus, in Akkeshi waters, C. pallasii successively used different habitats during its egg, larval and juvenile stages. A comparison of the current limited distribution of eggs and larvae with the distribution over the entire lake and bay areas in the 1950s and 1960s (periods of large catch size) indicates that the spawning grounds and larval habitats of C. pallasii have contracted to the lake area due to low spawning stock biomass in recent years.  相似文献   
545.
This study was conducted to clarify the relationships among immunoglobulin (Ig)M, IgG, IgA, β‐carotene, vitamin A and α‐tocopherol contents in colostrum of 24 Japanese Black multiparous cows in order to evaluate the role of IgM on colostral IgG and IgA production. Compared with colostral IgG, colostral IgM and IgA were very low but varied widely. There was positive correlation between colostral IgM and IgG, but colostral IgM was not related with colostral IgA. There was no relationship between colostral IgM and age of cows, although colostral IgG was increased with aging. There were positive correlations among colostral β‐carotene, vitamin A and α‐tocopherol and these vitamins were positively correlated with colostral IgM and IgG. These results indicate that fat‐soluble vitamins may affect colostral IgG and IgM in cows and colostral IgG increases with the increase of colostral IgM.  相似文献   
546.
547.
Probiotic bacteria such as lactic acid bacteria (LAB) have recently received attention as candidates for alternative anti‐microbial feed additives. We previously isolated Enterococcus faecium strain NHRD IHARA (FERM BP‐11090, NHRD IHARA strain) and reported its probiotic efficacy. However, we have not determined the effect of oral administration of heat‐killed cells of this strain. Here, we performed two experiments to investigate the effect of oral administration of the heat‐killed NHRD IHARA strain on post‐weaning piglets. In Experiment 1, there was a significant improvement in growth performance (P = 0.04) and increase in serum immunoglobulin A (IgA) production (P = 0.03) in the group fed heat‐killed cells. These results were similar to previous results we obtained with live cells. We also found changes in serum and fecal IgA production that were unrelated to the patterns of microbiotal change. In Experiment 2, we detected a significant improvement in villus growth in the jejunum (P = 0.0002). In conclusion, oral administration of the heat‐killed NHRD IHARA strain in post‐weaning piglets had the same efficacy as administration of the live strain. The heat‐killed NHRD IHARA strain can be used as feed additives to improve pig growth and health on commercial farms.  相似文献   
548.
549.
Summary Linear viscoelastic properties of laboratory handsheets have been investigated from the two dimensional aspect. According to the linear theory of viscoelasticity, the behavior of transverse isotropic materials such as handsheets subjected to plane stresses is fully described by the two in-plane relaxation functions G11 (t) and G12 (t). In the present paper, some viscoelastic characteristic functions describing responses to in-plane deformation histories are derived from G11 (t) and G12 (t) determined by strip biaxial stress relaxation testing. The predicted uniaxial relaxation function curve was in good agreement with the experimental one, and the viscoelastic Poisson's ratios in uniaxial stress relaxation and in uniaxial constant strain rate extension were decrease functions of time. Effects of beating on the areal dilatation and shear relaxation functions are discussed by introducing the classical concept of relaxation spectrum.  相似文献   
550.
Accumulating evidences indicate that an endotoxin originating from intestinal gram-negative bacteria may be involved in alcohol-induced liver injury including fatty liver. Therefore, whether immunization against intestinal bacterial endotoxin blocked fatty liver induced by chronic alcohol and diet including much-unsaturated fatty acid was investigated in rats. The titer of antibody against the endotoxin increased significantly after 13 weeks of continuous immunization. Daily alcohol treatment was initiated at 12 weeks and continued for 4 weeks. Plasma glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT) and triglyceride (TG) levels increased significantly in non-immunized rats receiving alcohol, but not in immunized rats. Continuous alcohol treatment gradually decreased the survival rate to 60% from 13 days after beginning administration in non-immunized, but not immunized, rats. A histochemical study revealed that continuous treatment with alcohol and unsaturated fatty acids caused fatty liver in non-immunized, but not immunized, rats. This study strongly supports the hypothesis that alcohol-induced fatty liver is due to a circulating endotoxin, and suggests that immunization for endotoxin prevent the alcoholic fatty liver.  相似文献   
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