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We evaluated the usefulness of MRI and compared it with CT for diagnosis of mesenteric lymphoma in a dog. The results in the plain CT, dynamic CT and plain MR (T1WI and T2WI) images suggested that the mass was a large single nodular lesion with abundant blood perfusion. On enhanced MRI(T1WI) , the mass was depicted as a tumor with adhesion to the gut wall. Exploratory laparotomy confirmed the mass was consistent with the findings on enhanced MRI. We think that MRI might be a useful imaging tool for diagnosis of canine mesenteric lymphoma.  相似文献   
33.
In order to evaluate the physiological roles of the testicular endothelin (Edn) signaling via Edn receptor subtype-A (Ednra) in mammals, the localization of Ednra was investigated by in situ hybridization and immunohistochemistry in the testis of rats, dogs, and monkeys. For in situ hybridization, a rat Ednra RNA probe which is highly homologous to the subcloned canine and monkey Ednra (88.7% and 87.9% identical, respectively) was used. Both Ednra mRNA and protein were detected in interstitial cells and cells in the basal compartment of the seminiferous tubules, mainly Sertoli cells, as well as spermatogonia and some early spermatocytes, but not spermatids. The localization pattern of Ednra was exhibited in a same manner among species, indicating that the physiological role of Edn signaling throughout Ednra was maintained in the mammalian testis.  相似文献   
34.
Xenografting of ovarian tissue into immunodeficient mice has been used as a model to study the dynamics of follicular development and provides an alternative method for the production of mature oocytes. In a previous experiment, we demonstrated that xenografted bovine secondary follicles developed to the antral stage in severe combined immunodeficient (SCID) mice. In the present study, we examined the development of bovine secondary follicles (140-190 microm in diameter) grafted into ovariectomized mice in comparison with intact female mice as a control. At 4 weeks after grafting, several antral follicles ranging from 350 to 550 microm (457.6 +/- 50.8 microm) in diameter were found in the control mice, while a single large (larger than 2.5 mm) antral follicle and other small follicles were observed in every ovariectomized mouse. At 6 weeks after grafting, the mean diameter of morphologically normal follicles had further increased in the control group (591.8 +/- 132.0 microm). In ovariectomized mice, however, the mean diameter of follicles decreased (4 weeks: 864.2 +/- 988.2 microm; 6 weeks: 496.5 +/- 137.6 microm), since the single large antral follicle observed at 4 weeks had degenerated by 6 weeks. In control mice, more than 70% of follicles were morphologically normal and formed an antrum, and most of the follicles contained morphologically normal oocytes which grew to 122.5 +/- 2.2 microm. In ovariectomized mice, morphologically normal oocytes also grew larger than before grafting, but their survival rate was significantly lower than that in control mice. These results suggest that ovariectomy of host mice alters the developmental pattern of xenografted bovine secondary follicles to accelerate a single follicle to develop in the graft.  相似文献   
35.
Recently we reported that a chimeric molecule containing mouse transferrin receptor and immunoglobulin G1 (IgG1) Fc, mTR-Fc, induced higher immune responses and can be used as a vaccine adjuvant. In this study, the immunological property of the molecule was investigated. Although, the mTR-Fc did not activate complement classical pathway, it was recognized by activated macrophage as like intact IgG Fc, which is recognized by macrophage via Fcgamma receptor. In addition, we found that splenocyte simultaneously exposed to lipopolysaccaride (LPS) and mTR-Fc produced higher amount of interleukin-10, comparing to that exposed to only LPS. These results suggest that the mTR-Fc molecules conserved the IgG Fc property to biasing immune responses via modulation of cytokine production by antigen presenting cell.  相似文献   
36.
Previously we reported that immunization with pseudorabies virus (PRV), harboring chimeric Fc on the surface of the virus particles (PRV/Fc), induced higher immune responses than normal PRV particles. The chimeric Fc was fused with mouse transferrin receptor of transmembrane domain (mTR) and the Fc region of immunoglobulin G1. Since it has been reported that some chimeric protein of Fc and self-antigen induce auto-reactive antibodies, in this present study, we examined whether PRV/Fc induces auto-reactive antibodies that react with mTR. PRV/Fc immunized mice produced higher levels of anti-PRV antibodies and antibodies that reacted with mouse-derived 3T3/A31 cells (A31 cell), compared to normal PRV immunized mice. However, antibodies that reacted with mTR in A31 cells were not detected in both Western blot analyses and indirect immunofluorescence assay. The antibodies reacted with an antigen of approximately 16 kDa in A31 cells, but this antigen has a different molecular mass from that of mTR. The antibody also reacted with the antigen of approximately 16 kDa in RK13 cells in which the virus had been propagated. In addition, antibodies induced by immunization with normal PRV also reacted with the same antigen in A31 and RK13 cells. Moreover, neither kidney disorders, in which high levels of mTR were expressed, nor clinical symptoms of autoimmune diseases were observed in mice immunized with either PRV or PRV/Fc. These results indicated that the antibodies were not induced by mTR-Fc, but were instead induced by trace amounts of RK13 derived antigens contained in PRV or PRV/Fc preparations, and cross-reacted with equivalent molecules in mouse derived A31 cells. Therefore, this study confirmed that immunization with PRV/Fc did not induce harmful auto-reactive antibodies.  相似文献   
37.
The reaction between Amadori compounds and cysteine was investigated. When 1-deoxymaltulosyl-glycine (glycyl-fructosyl-glucose) was heated at 100 degrees C with cysteine in a neutral aqueous solution, a novel intermediate composed of 1-deoxyosone and cysteine was detected. NMR and mass spectrometry studies revealed the structure of the isolated intermediate to be 7,8a-dihydroxy-4a-methyl-8-(alpha-d-glucopyranosyloxy)hexahydro-5-oxa-4-thia-1-azanaphthalene-2-carboxylic acid. This intermediate easily generated isomaltol and acetylfuran as volatile compounds in 1 mol/L HCl at 100 degrees C.  相似文献   
38.
39.
In this study, an inexpensive camera-observation system called the Crop Phenology Recording System (CPRS), which consists of a standard digital color camera (RGB cam) and a modified near-infrared (NIR) digital camera (NIR cam), was applied to estimate green leaf area index (LAI), total LAI, green leaf biomass and total dry biomass of stalks and leaves of maize. The CPRS was installed for the 2009 growing season over a rainfed maize field at the University of Nebraska-Lincoln Agricultural Research and Development Center near Mead, NE, USA. The vegetation indices called Visible Atmospherically Resistant Index (VARI) and two green–red–blue (2g–r–b) were calculated from day-time RGB images taken by the standard commercially-available camera. The other vegetation index called Night-time Relative Brightness Index in NIR (NRBINIR) was calculated from night-time flash NIR images taken by the modified digital camera on which a NIR band-pass filter was attached. Sampling inspections were conducted to measure bio-physical parameters of maize in the same experimental field. The vegetation indices were compared with the biophysical parameters for a whole growing season. The VARI was found to accurately estimate green LAI (R2 = 0.99) and green leaf biomass (R2 = 0.98), as well as track seasonal changes in maize green vegetation fraction. The 2g–r–b was able to accurately estimate total LAI (R2 = 0.97). The NRBINIR showed the highest accuracy in estimation of the total dry biomass weight of the stalks and leaves (R2 = 0.99). The results show that the camera-observation system has potential for the remote assessment of maize biophysical parameters at low cost.  相似文献   
40.
We studied the effects of a single oral administration of ferulic acid (FA) on the blood pressure (BP) and lipid profile in stroke-prone spontaneously hypertensive rats (SHRSP). Male 12-week-old SHRSP were administered FA (9.5 mg/kg of body weight) and distilled water as the control (C) (1 mL) via a gastric tube. The hypotensive effect of FA was observed at the lowest value after 2 h administration. A decrease in the angiotensin-1-converting enzyme (ACE) activity in the plasma corresponded well with the reduction of BP. Plasma total cholesterol and triglyceride levels were lower after 2 h administration. The mRNA expression of genes involved in lipid and drug metabolism was downregulated in the FA group. These results suggest that oral administration of FA appears beneficial in improving hypertension and hyperlipidemia.  相似文献   
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