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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   
73.
Angiogenesis in the developing corpus luteum (CL) is a prerequisite for establishment and maintenance of an early pregnancy. To explore the physiological significance of insulin-like growth factor-binding protein-7 (IGFBP7) in the developing CL, the effects of IGFBP7 on vascular endothelial growth factor (VEGFA)- and luteinizing hormone (LH)-induced in vitro tube formation were tested using isolated luteal microvascular endothelial cells (LECs). Capillary-like tube formation of LECs and their proliferation were stimulated by both VEGFA and LH. IGFBP7 treatment suppressed VEGFA- or LH-induced tube formation. The proliferation and migration of LECs, and phosphorylation of mitogen-activated protein kinase kinase and extracellular signal-regulated kinase 1/2 were inhibited by IGFBP7. Furthermore, IGFBP7 attenuated VEGFA-enhanced cyclooxygenase (COX)-2 mRNA expression and prostaglandin E2 secretion. These findings suggest the possibility that luteal IGFBP7 secretion may suppress the stimulatory effect of VEGFA on angiogenesis in the early CL.  相似文献   
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This study aimed to evaluate the effects of dietary lysine/protein ratio and fat levels on the growth, carcass characteristics and meat quality of finishing pigs fed feed made from food waste, including noodles and chocolate. Four dietary treatments, 2 levels of lysine/protein ratio (0.035 and 0.046) and 2 levels of fat (3.3% and 6.0%), were adapted to a 2 × 2 factorial arrangement. Each diet for the finishing pigs contained the same levels of adequate crude protein (16%) and lysine (0.58–0.75%), and similar levels of high total digestible nutrients (90.2–92.6%). In total, 32 LWD pigs with an average body weight of 57.2 kg were assigned to 4 dietary groups. The pigs were slaughtered at about 115 kg. Growth performance was not influenced by the dietary treatments. Carcass characteristics were slightly influenced by the dietary fat level. As the dietary lysine/protein ratio decreased, the marbling score of Longissimus dorsi muscle increased and the intramuscular fat (IMF) increased from 6.82% to 9.46%. Marbling score was not significantly influenced by the dietary fat level. These results indicate that IMF increased without adverse effects on growth, carcass characteristics and meat quality, when pigs were fed a diet with low lysine/protein ratio.  相似文献   
76.
Eucrites are a class of basaltic meteorites that share common mineralogical, isotopic, and chemical properties and are thought to have been derived from the same parent body, possibly asteroid 4 Vesta. The texture, mineralogy, and noble gas data of the recently recovered meteorite, Northwest Africa (NWA) 011, are similar to those of basaltic eucrites. However, the oxygen isotopic composition of NWA011 is different from that of other eucrites, indicating that NWA011 may be derived from a different parent body. The presence of basaltic meteorites with variable oxygen isotopic composition suggests the occurrence of multiple basaltic meteorite parent bodies, perhaps similar to 4 Vesta, in the early solar system.  相似文献   
77.
How nitrogen (N) cycling is regulated and how environmental change affects it are major study questions in forest ecology, because N availability often limits the primary production of plants in many forest ecosystems. These are being extensively highlighted because of growing concerns regarding chronic and elevated N deposition in forest ecosystems on a global scale. Until now, N cycling has been mainly documented in association with various environmental factors other than microbial communities. However, with the recent rapid development in culture-independent molecular-based techniques, microbial ecologists have discovered that alterations in N cycling are highly associated with alternations in microbial communities through changes in either resource supplies or processing rates. In this review, we describe nitrification as a key N cycling process and present general approaches to associate the nitrification process with the nitrifying community in forest soils. Furthermore, we briefly summarize currently available information about the relationship between the process and nitrifying community dynamics in soil. We suppose that linking N cycling processes with microbial community dynamics provides a deeper insight into the mechanisms regulating N cycling in forest ecosystems.  相似文献   
78.
Severe spotting and blight of leaves caused by Colletotrichum destructivum were found on snapdragon (Antirrhinum majus L.), a scrophulariaceous ornamental, in open fields in Shizuoka Prefecture, Japan, from June through September 2004. The fungus is added to the group of the pathogens causing anthracnose of snapdragon.  相似文献   
79.
Diabetes mellitus (DM) and obesity are believed to be risk factors for colorectal cancer in humans. In experiment 1, male nondiabetic Long-Evans Tokushima Otsuka (LETO) rats and Otsuka Long-Evans Tokushima Fatty (OLETF) rats, a model animal of type 2 DM, were whole-body X-irradiated (4 Gy) at 6 and 8 weeks of age and euthanized at 78 weeks of age (n=15, respectively). The incidences of small intestine adenocarcinoma in LETO and OLETF rats were 0% and 30%, respectively. In experiment 2, male LETO and OLETF rats (n=24, respectively) were given s.c. injections of 15 mg/kg azoxymethane (AOM) once weekly for 3 weeks and euthanized at 36 weeks of age. The incidences of Zymbal gland tumors in LETO and OLETF rats were 0% and 67%, respectively (P<0.001), whereas those of small intestine adenocarcinoma were 0% and 43% (P<0.001) and those of cecum/colon adenocarcinoma were 46% and 79% (P<0.05), respectively. Fatty change of hepatocytes was common in OLETF rats (63%) but not in LETO rats. Serum triglyceride and free fatty acid levels in OLETF rats were significantly higher than in LETO rats at sacrifice, whereas serum insulin levels in OLETF rats were very diverse. These data suggest that hyperlipidemia plays a significant role in high susceptibility to lower intestinal tract carcinogenesis in OLETF rats; this strain is susceptible to AOM-induced Zymbal gland carcinogenesis.  相似文献   
80.
Intrathecal (IT) immunization involves injecting antigens directly into the intraventricular or subarachnoid spaces, or brain, to induce antigen-specific antibodies (Ab) in the cerebrospinal fluid (CSF). In the present study, rabbits were immunized IT with inactivated rabies virus to investigate the origins of CSF Ab. The time course of Ab induction and tumor necrosis factor-alpha expression suggested the possibility that the CSF Ab originated in the serum. In addition, Ab-producing cells infiltrated around the blood vessels of the brain, suggesting local production of Ab within the central nervous system (CNS). Furthermore, subcutaneous (SC) immunization prior to IT immunization induced a rapid and magnified Ab response in the CSF compared with IT immunization alone. These results were confirmed by the fact that mice immunized SC prior to IT were more resistant to intracerebral challenge with rabies virus than mice immunized via the IT route alone. Taken together, these results suggest that combined SC and IT immunization is a more effective vaccination protocol for prophylaxis and treatment of rabies.  相似文献   
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