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181.
OBJECTIVE: The aim of this study is to examine the correlation between tumor angiogenesis and response to preoperative radiotherapy evaluated using 201Tl single photon emission computed tomography (Tl SPECT) in oral cavity squamous cell carcinoma (SCC). METHODS: Tl SPECTs before and after preoperative radiotherapy were obtained from 11 patients diagnosed with SCC in oral cavity. Regions of interest were set around the tumor and scalp respectively, and the ratio of mean counts in the tumor to those in the scalp was calculated (T/N). Immunohistochemical staining for investigating microvessel density of pre-treatment biopsy specimen was performed using CD31 monoclonal antibody. We compared microvessel density with semi-quantitative parameters obtained using Tl SPECT (T/N at pre- an post-treatment, reduction ratio) and prognosis. RESULTS: The subgroup with higher microvessel density showed a significantly higher reduction ratio than the one with lower microvessel density. Regarding prognosis, the subgroup with locoregional recurrent disease exhibited a significantly higher microvessel density than the one without recurrence. CONCLUSIONS: In SCC of the oral cavity, there was a significant correlation between microvessel density and response to preoperative radiotherapy. Namely, it was revealed that change of 201Tl uptake after preoperative radiotherapy correlated with tumor angiogenesis of oral cavity SCC.  相似文献   
182.
A 30-year-old man presented with a 2-year history of intermittent headache. No neurological deficit was detected. Computed tomography (CT) and magnetic resonance imaging showed a tumor with a diameter of 2.5 cm in the left anterior skull base associated with bone scalloping on three-dimensional CT. Angiography showed a hypovascular tumor. Craniotomy demonstrated a tumor in the region of the left olfactory groove attached to the anterior part of the cribriform plate. The histological diagnosis was schwannoma. Schwannoma arising from near the olfactory groove is rare, with only 13 other cases reported. The precise origin of these tumors is not well understood, but the tumor in this case probably arose from the fila olfactoria, because the olfactory bulb was involved in the tumor, whereas the olfactory tract remained intact.  相似文献   
183.
Idiopathic (primary) tubulointerstitial nephritis (TIN) of childhood is relatively rare. Four children, two with concomitant uveitis, aged 8–14 years, with idiopathic TIN who underwent repeat renal biopsy were retrospectively evaluated. At presentation, all had a significant elevation of the urinary 2-microglobulin/creatinine ratio (2MG ratio), ranging from 10,100 to 44,550, with increased histological indices of tubulointerstitial scores (TI scores) in excess of 6 points. Three of the children received prednisolone (PSL) therapy following diagnosis, while the remaining child received the therapy 30 months after the first renal biopsy. In the children that received prompt PSL therapy, a rapid decrease in urinary 2MG ratio was observed and the TI scores obtained at a mean interval of 16 months after the first biopsy decreased to less than 5, while preserving renal function. In the remaining child that received delayed PSL therapy, persistent elevations of urinary 2MG ratio and TI scores were observed. He subsequently progressed to chronic renal insufficiency. These clinical findings suggest that persistent elevations of urinary 2MG ratio and TI scores are indicators of progression of renal failure in TIN. For successful treatment, early therapeutic intervention should be deployed in selected patients with severe idiopathic TIN.  相似文献   
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We describe a case involving a 75-year-old woman presenting with a femur fracture 10 years after radiation therapy for metastatic breast cancer, which developed in the right femur. The lesion showed complete response with bone healing following radiation therapy; however, the patient sustained a femur fracture ten years later. Histological examination of the specimens obtained from the lesion revealed features of radiation osteonecrosis, but there was no histological evidence of tumor. To our knowledge, there has been no reported case of pathological fracture ten years after radiation therapy from radiation osteonecrosis rather than progression of the metastatic lesion. Late complications of radiation therapy should be considered with care, even when metastatic lesions demonstrate complete response to treatment.  相似文献   
187.
Hepatitis B virus (HBV) mutants with deletions in the preS region have not been evaluated for association with viral genotypes. In a case-control study, HBV DNA samples collected from 80 each of carriers infected with HBV genotype B or C were examined for preS deletions. PreS deletion mutants were found in a total of 37 of 160 (23%) HBV carriers. Carriers with preS deletion mutants were older (56.0 +/- 12.7 vs 49.3 +/- 16.9 years, P < 0.05), were infected more frequently with HBV genotype C (84% vs 40%, P < 0.05), and had more advanced disease, such as liver cirrhosis and hepatocellular carcinoma (54% vs 31%; P < 0.05), than did those without such mutants. In a multivariate analysis, genotype C (odds ratio [OR] = 9.3, P < 0.001) and advanced liver disease (OR = 3.1, P < 0.01) were the most significant variables in association with preS deletions. A direct repeat sequence (TCAGG) was found at the start or at the end of preS1 deletions in 6 of the 20 (30%) cases examined, and preS2 deletions in these cases were clustered over the 5'-terminal half of this region. These results indicate that the development of preS deletion mutants depends on HBV genotypes and that it may be associated with progressive liver disease.  相似文献   
188.
Recent studies suggest a chemical perception of dietary fat in the oral cavity. To examine the role of gustation for the recognition of oleate and triolein, very short-term (5-min), two-bottle preference tests were conducted in anosmic rats. To minimize the effects of olfaction, texture and postingestive effects, rats were rendered anosmic with intranasal zinc sulfate, test substances were suspended in 0.3% xanthan gum solution and test fluids were offered for 5 min. Rats preferred oleate fluid but not triolein fluid to the control of 0.3% xanthan gum solution. The preference threshold for oleate in the rat oral cavity was between 0.2% and 0.5%. In the two-bottle preference tests between oleate and triolein, rats preferred oleate fluid to triolein fluid, showing discrimination of oleate and triolein. The results suggest that rat recognizes oleate by a gustatory cue and that fatty acid but not triglyceride is important for gustatory recognition of fat.  相似文献   
189.
BACKGROUND: Extracellular signal-regulated kinase 2 (ERK2) has been implicated in cell proliferation, differentiation, and survival. However, its role in vivo remains to be determined. RESULTS: Here we show that the targeted disruption of the mouse ERK2 gene results in embryonic lethality by E11.5 and severe abnormality of the placenta. In these animals, the labyrinthine layer of the placenta is very thin and few foetal blood vessels are observed. ERK2 mutants can be rescued by the transgenic expression of ERK2, demonstrating that these abnormalities are caused by ERK2-deficiency. Although ERK2-deficient fetuses are much smaller than wild-type littermates, this seems to be secondary to malfunction of the placenta. When the placental defect is rescued by tetraploid-aggregation, ERK2-deficient foetuses grow as well as littermate controls. CONCLUSION: These observations indicate that ERK2 is essential for placental development and suggest that ERK2 in the trophoblast compartment may be indispensable for the vascularization of the labyrinth.  相似文献   
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