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101.
This report describes a spontaneous nephroblastoma with lung metastasis in a 10-week-old male Crl:CD(SD) rat. Macroscopically, a white mass in the kidney and two white masses in the lung were observed. Histopathologically, the renal mass was located in the cortex of a kidney, and it caused pressure on the surrounding renal parenchyma. Three components could be distinguished in the tumor: blastemal, epithelial (primitive glomerular/tubular structures) and mesenchymal (neoplastic connective tissues) elements. Immunohistochemically, the tumor cells were positive for Wilms tumor 1 protein (WT1) and vimentin. Metastasis was found in the lung. Thus, the case was diagnosed as a nephroblastoma with lung metastasis.  相似文献   
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The development and regeneration of the pancreas is of considerable interest because of the role of these processes in pancreatic diseases, such as diabetes. Here, we sought to develop a large animal model in which the pancreatic cell lineage could be tracked. The pancreatic and duodenal homeobox-1 (Pdx1) gene promoter was conjugated to Venus, a green fluorescent protein, and introduced into 370 in vitro-matured porcine oocytes by intracytoplasmic sperm injection-mediated gene transfer. These oocytes were transferred into four recipient gilts, all of which became pregnant. Three gilts were sacrificed at 47–65 days of gestation, and the fourth was allowed to farrow. Seven of 16 fetuses obtained were transgenic (Tg) and exhibited pancreas-specific green fluorescence. The fourth recipient gilt produced a litter of six piglets, two of which were Tg. The founder Tg offspring matured normally and produced healthy first-generation (G1) progeny. A postweaning autopsy of four 27-day-old G1 Tg piglets confirmed the pancreas-specific Venus expression. Immunostaining of the pancreatic tissue indicated the transgene was expressed in β-cells. Pancreatic islets from Tg pigs were transplanted under the renal capsules of NOD/SCID mice and expressed fluorescence up to one month after transplantation. Tg G1 pigs developed normally and had blood glucose levels within the normal range. Insulin levels before and after sexual maturity were within normal ranges, as were other blood biochemistry parameters, indicating that pancreatic function was normal. We conclude that Pdx1-Venus Tg pigs represent a large animal model suitable for research on pancreatic development/regeneration and diabetes.  相似文献   
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The purpose of this retrospective study was to describe pre‐ and postcontrast computed tomographic (CT) characteristics of confirmed nonparenchymal hemangiosarcoma in a group of dogs. Medical records were searched during the period of July 2003 and October 2011 and dogs with histologically confirmed nonparenchymal hemangiosarcoma and pre‐ and postcontrast CT images were recruited. Two observers recorded a consensus opinion for the following CT characteristics for each dog: largest transverse tumor diameter, number of masses, general tumor shape, character of the tumor margin, precontrast appearance, presence of dystrophic calcification, presence of postcontrast enhancement, pattern of postcontrast enhancement, presence of regional lymphadenopathy, and presence of associated cavitary fluid. A total of 17 dogs met inclusion criteria. Tumors were located in the nasal cavity, muscle, mandible, mesentery, subcutaneous tissue, and retroperitoneal space. Computed tomographic features of nonparenchymal hemangiosarcoma were similar to those of other soft tissue sarcomas, with most tumors being heterogeneous in precontrast images, invasive into adjacent tissue, and heterogeneously contrast enhancing. One unexpected finding was the presence of intense foci of contrast enhancement in 13 of the 17 tumors (76%). This appearance, which is not typical of other soft tissue sarcomas, was consistent with contrast medium residing in vascular channels. Findings indicated that there were no unique distinguishing CT characteristics for nonparenchymal hemangiosarcoma in dogs; however, the presence of highly attenuating foci of contrast enhancement may warrant further investigation in prospective diagnostic sensitivity and treatment outcome studies.  相似文献   
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Nasal lymphoma (NL) is the most common nasal tumor in cats, and radiotherapy, chemotherapy, or a combination of these treatments have been described as the treatment for this disease. However, the previous studies included various machines and protocols of radiotherapy. Therefore, we aimed to retrospectively compare the prognosis among cases treated with palliative hypofractionated radiotherapy, chemotherapy, and a combination of them with united machine and protocol of radiotherapy. When compared overall survival and progression free survival, there was no significant difference among these three groups. The data of this study suggested that similar efficacy could be achieved by palliative hypofractionated radiotherapy, chemotherapy, or a combination of them.  相似文献   
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A simple and rapid method for determining 1-deoxynojirimycin (DNJ), a potent glucosidase inihibitor present in mulberry leaves (Morus alba and Morus bombysis), by high-performance liquid chromatography coupled to an evaporative light scattering detector (ELSD) has been developed. DNJ was separated from an extract of mulberry leaves on a TSKgel Amide-80 column, which is a representative column for hydrophilic interaction chromatography. During postcolumn detection, DNJ was detected by ELSD and concurrently identified by mass spectrometry. The detection limit was 100 ng. This method is sufficiently sensitive for determining DNJ in mulberry leaves and other related products.  相似文献   
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To clarify the feeding strategy of pelagic larvae of stone flounder in Mutsu Bay, the dietary composition and pray size was investigated from February to April during 1989–1999. Diets were compared with the numerical and volumetric compositions and frequency of occurrence of each prey species. Mensuration formulae were applied to estimate individual prey volume in the diet, while the length of planktonic species was measured from net and water samples. Prey shapes were assumed as sphere, cylinder, ellipsoid, pyramid, two elliptical cones, or a combination of ellipsoid and cylinder. Prey-size range increased as the larvae grew. Preflexion larvae fed mainly on copepod nauplii. Flexion and postflexion larvae ingested primarily appendicularians, with a suggestion that these larvae might depend on some parts of the microbial food web. Low frequencies of flexion and postflexion larvae with empty guts (1.7 and 1.4%, respectively) might be derived from feeding on slow-swimming appendicularians. From a size comparison between ‘house’-like organ length and trunk length of the appendicularian Oikopleura sp., almost all house-like organs with trunks in the larval diet were nonexpanded ‘house rudiments’, not expanded ‘houses’. Thus, stone flounder larvae may not chew the houses, but swallow the house rudiments with trunks.  相似文献   
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