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181.
To investigate the roles of mammary PTHrP in calcium uptake and/or release in the mammary gland of cows, plasma PTHrP and Ca levels, and their arterial-venous differences were examined in a Jersey cow during the periparturient period. Levels of Ca in both abdominal aorta and abdominal subcutaneous vein blood slightly decreased around the parturition and at 24 days after the parturition, however, no remarkable arterial-venous differences were observed. Plasma PTHrP levels in both arterial and venous samples were below the detection limit (0.57 pmol/l) during the experimental period. Milk PTHrP and Ca levels were measured in 9 Holstein dairy cows. Although plasma PTHrP levels in all arterial and venous samples were also below the detection limit, milk PTHrP and Ca levels were remarkably high, ranging from 14,900 pmol/l to 41,200 pmol/l and from 772 mg/l to 1,200 mg/l, respectively. In addition, a significant positive correlation (P<0.01) was observed between milk PTHrP and Ca levels. These results suggested that mammary PTHrP is closely related to Ca concentration in the milk.  相似文献   
182.
The aim of the present study was to evaluate short term urinary NAG levels in a model of reduced kidney mass. The half and quarter kidney mass were made from ligation of the renal artery. Both groups decreased in the level of excreted NAG on day 1 and 2 after operation. On day 5 after operation, both groups achieved urinary enzyme levels comparable to that of the sham-operated group. The remaining compensated nephrons held normal range of excreted urinary NAG levels, although reduced number of nephrons resulted in a decline in urinary NAG levels.  相似文献   
183.
A cell line, MCO-Y4, was established from a mammary gland osteosarcoma of a 16-year-old female mongrel dog. Histopathologically the tumor was composed of osteoblastic cells with an osteoid meshwork and chondroid matrix. The mean doubling time of the cells at the 93rd passage was 32.39+/-4.66 hr. Immunohistochemically, the osteoblastic and chondroblastic cells were positive for bone morphogenetic protein (BMP)-2/4 and BMP receptor (BMPR) II. The cultured cells were spindle in shape during the growth and the confluent phases. No tumor matrix was detected in the culture dish by alcian blue staining or von-Kossa silver impregnation. MCO-Y4 cells on the chamber slides showed intense immunoreactivity for BMP-2/4 and BMPR II. Noggin, an antagonist for BMP-2/4, showed the growth inhibition on MCO-Y4 cells. In addition, fibronectin might be potential for stimulating growth of MCO-Y4 cells. When transplanted into severe combined immunodeficiency mice, the cells formed tumors consisting of solid proliferation of osteoblastic and fibroblastic cells with woven-bone trabeculae. These tumor cells were intensely positive for BMP-2/4 and BMPR II. Our results suggested that the cell line might be useful for studying the role of BMPs in canine osteosarcoma and the mechanism of ossification.  相似文献   
184.
To clarify the crucial role of Toll-like receptor (TLR) 2 and TLR9 in immature gut-associated lymphoid tissues (GALT), we focused on the expression of TLR2 and TLR9 and the immune responses induced by their ligands in the GALT of presuckling newborn swine. Quantitative real-time PCR revealed that TLR2 and TLR9 mRNA were expressed at detectable levels in all tested tissues (heart, thymus, lung, spleen, liver, kidney, skeletal muscle, duodenum, jejunum, ileum, ileal Peyer patches (Pps), and mesenteric lymph nodes (MLN)). In particular, in immature intestinal tissues and GALT, TLR2 and TLR9 mRNA were expressed at higher levels in ileal Pps and MLN than in the duodenum, jejunum, and ileum. We confirmed that the TLR2 and TLR9 proteins were also highly expressed and that their ligands were preferentially recognized by TLR2- or TLR9-expressing cells in the MLN and ileal Pps. Zymosan, CpG2006, and lactic acid bacteria could promote mitogenesis and production of multiple cytokines by the MLN and ileal Pps. In addition, double immunostaining for cytokeratin 18 and either TLR2 or TLR9 revealed that both TLR2 and TLR9 are strongly expressed in the columnar membranous (M) cells. Interestingly, while the apical membrane of the columnar M cells strongly expressed TLR2 protein and preferentially recognized zymosan, both "TLR2 expression on the apical membrane" and "TLR2-mediated zymosan binding" were negligible in neighboring enterocytes. These results indicate that TLR2 and TLR9 allow MLN and ileal Pps to respond to a variety of bacterial components immediately after birth, thereby providing newborns with a host defense system.  相似文献   
185.
OBJECTIVE: To evaluate the efficacy of percutaneous administration of iohexol into the popliteal lymph node as a non-invasive technique for thoracic duct lymphangiography in dogs. STUDY DESIGN: Experimental study and clinical report. ANIMALS: Normal adult dogs (n=4) and 1 dog with recurrent chylothorax. METHODS: For the experimental study, 4 dogs (weight, 8.4-12.3 kg) had 5-10 mL iohexol injected percutaneously into 1 popliteal lymph node and then thoracic radiographs were taken. Popliteal lymph nodes were examined by histopathology 8 days later. One 25-kg dog with recurrent chylothorax had 25 mL iohexol injected into the right popliteal lymph node followed by thoracic radiography. RESULTS: In experimental dogs, the thoracic duct was best visualized on thoracic radiographs after administration of 10 mL iohexol. Clinically, no abnormalities were identified in the injected limb and except for 1 dog that had large numbers of siderocytes and erythrophagocytic macrophages in the injected lymph node, the histopathologic findings in the other injected popliteal lymph nodes were not different from contralateral nodes. In the clinical case, the thoracic duct was visualized, but there was leakage of iohexol around the node. CONCLUSION: The thoracic duct in dogs can be visualized by lymphography after percutaneous injection of iohexol (1 mL/kg at 2 mL/min) into the popliteal lymph node. CLINICAL RELEVANCE: Percutaneous popliteal lymph node administration of iohexol should be considered as an alternative to mesenteric lymph node injection for radiographic identification of the thoracic duct in dogs.  相似文献   
186.
In our studies of the chain-breaking antioxidant mechanism of natural phenols in food components, ferulic acid, a phenolic acid widely distributed in edible plants, especially grain, was investigated. The radical oxidation reaction of a large amount of ethyl linoleate in the presence of the methyl ester of ferulic acid produced four types of peroxides as radical termination products. The isolation and structure determination of the peroxides revealed that they had tricyclic structures which consisted of ethyl linoleate, methyl ferulate, and molecular oxygen. Based on the formation pathway of the products, a radical scavenging reaction occurred at the 3'-position of the ferulate radical with the four types of peroxyl radicals of ethyl linoleate. The produced peroxides subsequently underwent intramolecular Diels-Alder reaction to afford stable tricyclic peroxides.  相似文献   
187.
188.
The db/db mouse is one of the diabetes mellitus animal models and if the pathophysiological stages of diabetic changes in the mouse model could simulate the stages in human diabetes, the db/db mouse could be used to better evaluate drug candidates. Blood insulin, HbA1c levels and morphological features of pancreatic islets in db/db mice were evaluated to determine the pathophysiological stage. At 6 weeks of age, db/db mice showed the highest level of plasma insulin and lowest level of HbA1c, and histopathological examination revealed enlarged islets with a circular shape and hypertrophic islet cells. By 9 and 12 weeks of age, the plasma insulin levels had decreased to mid levels and HbA1c had increased to mid to high levels; histopathological examination at this time revealed two types of islets coexisting, enlarged circular islets and small irregular-shaped islets. By 15 and 22 weeks of age, plasma insulin had decreased further to low levels and HbA1c was at its highest level; the histopathological examination at this time revealed an increase in irregular-shaped and small islets. Based on blood insulin levels, HbA1c levels and histopathology findings in the db/db mice in this study, the clinical staging of diabetic changes were recognized. The pathophysiological stages of diabetes mellitus in this animal model were similar to the stages in humans.  相似文献   
189.
On March 22, 1998, a mature, male, hyposthenic Pacific striped dolphin (Lagenorhynchus obliquidens) was stranded at Aoshima Beach in Miyazaki prefecture, Japan. A necropsy performed 14 hr after death revealed mild diffuse congestion and edema of the leptomeninges and mild pulmonary atelectasis. Histopathologically, non-purulent inflammatory were observed throughout the cerebrum, thalamus, midbrain, pons, medulla oblongata, and spinal cord. Hematoxylin and eosin stain revealed no viral inclusion bodies. Immunohistochemistry using a monoclonal antibody against nucleoprotein of canine distemper virus (CDV-NP) revealed a number of CDV-NP-positive granular deposits in the cytoplasm and cell processes of the degenerating or intact neurons. The present paper is a first report of spontaneously occurred morbillivirus infection in a dolphin at the Pacific Ocean around Japan.  相似文献   
190.
A gelatinous focus with cystic spaces, was found in the posterior funiculus of the 2nd to 3rd lumbar levels of the spinal cord of a Japanese Black heifer, 2 years old, with clinical signs of severe dysstasia. Histopathological examination revealed that the spinal lesion consisted of multifocal and diffuse proliferation of round cells with abundant vacuolar cytoplasm and hyperchromatic nuclei. In the lesions there was a number of cystic spaces containing aggregates of small round cells. The neoplastic foci showed a honeycomb structure divided by thin blood vessels, representing typical lesions of oligodendroglioma. Diffuse and multifocal proliferation of these round cells were also recognized in the subarachnoidal space in the sacral spinal cord. Immunohistochemically, the proliferating round cells were negative for glial fibrillary acidic protein. Based on these morphological features, the case was diagnosed as lumbar spinal oligodendroglioma with diffuse arachnoidal dissemination.  相似文献   
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