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991.
992.
993.

Purpose

In the recent years in Japan, an increasing number of patients with neuroblastoma (NB) are being treated by the “delayed local treatment (DL)” policy, undergoing surgery after the completion of high-dose chemotherapy with hematopoietic stem cell rescue (HDC). We reviewed the histopathological findings of second-look operations, including those of patients treated with DL.

Patients

From 1998 to 2013, 26 patients with high-risk NB underwent radical operation following chemotherapy. Surgery was performed after induction chemotherapy in 17 cases (standard; STD), whereas 9 cases completed induction chemotherapy and HDC before undergoing tumor resection (DL). The amount of necrosis and the degree of differentiation within the post-treatment tumor were assessed.

Results

Eighty-eight percent of the tumors showed necrosis in more than 1/3 of the specimen. Two DL cases showed complete disappearance of viable tumor cells. Amount of necrosis did not affect the prognosis of the patient. Tumors with immature, poorly differentiated phenotypes showed an extremely aggressive thereafter. Though not statistically proven, 123I-MIBG (metaiodobenzylguanidine) uptake may be correlated with the amount of viable cells remaining within the tumor, but not with the degree of differentiation.

Conclusions

Our results support the previous reports advocating that tumors that sustain unfavorable histology after chemotherapy behave aggressively thereafter.  相似文献   
994.
Ewing sarcoma (ES) of the bladder is extremely rare. Here we report the successful treatment of the youngest case of ES arising from bladder encountered to date and a literature review. A 10-year-old boy who presented with polyuria and lower abdominal swelling was found to have a 13 cm mass arising from the bladder localized to the center of the lower abdomen. Biopsy confirmed ES. Following chemotherapy, the mass shrank to 5 cm and was found to be localized to the right side of the bladder with invasion of the right vas deferens. One-third of the right side of the bladder and part of the right vas deferens were resected. No viable cancer cells were detected in the resected specimen, and the surgical margins were reported to be negative. The patient is currently well with no recurrence or metastases after 11 months. There are 12 cases of Ewings sarcoma arising from the bladder reported in the English literature; two cases in children. Our case will be the third pediatric case and the youngest.  相似文献   
995.
996.
Alterations in histoarchitecture of the brainstem were examined immunohistochemically in 4‐week‐old rats with a single whole body X‐irradiation at a dose of 0.5, 1.0, or 1.5 Gy on embryonic day (ED) 15 using anti‐heat shock protein 25 (HSP25). HSP25 immunostaining was seen in the neuronal perikarya of cranial nerve motoneurons, that is, the motor and mesencephalic nuclei of the trigeminal nerve, facial nucleus, abducens nucleus and accessory facial nucleus in the pons, and the ambiguous nucleus, dorsal nucleus of vagus nerve and hypoglossus nucleus in the medulla oblongata of intact controls. In 0.5 to 1.5 Gy‐irradiated rats, HSP25 immunostaining in those neurons was more intense than in controls, while the most intense immunostaining was marked in 1.5 Gy‐irradiated rats. HSP25 immunostaining was also apparent in the spinal tract of the trigeminal nerve and facial nerve tracts in 0.5 to 1.5 Gy‐irradiated rats, but was faint in controls. Interestingly, HSP25 immunostaining was aberrantly enhanced in dendritic arbors in the magnocellular region of medial vestibular nucleus of 0.5–1.5 Gy‐irradiated rats. Those arbors were identified as excitatory secondary vestibulo‐ocular neurons by double immunofluorescence for HSP25 and SMI‐32. The results suggest an increase of HSP25 expression in cranial nerve motoneurons and their related fiber tracts from prenatal exposure to ionizing irradiation. This may be an adaptive response to chronic hypoxia due to malformed brain arteries caused by prenatal ionizing irradiation.  相似文献   
997.
We verified the feasibility of telediagnosis of fetal disease by (i) grading telediagnosis by a pediatric cardiologist into five confidence levels; and (ii) comparison of fetal telediagnosis with hands‐on fetal diagnosis or postnatal diagnosis. In 114 patients suspected of having heart disease (real time, n = 15; recorded image transmission, n = 99), 79 patients were in level 5 (excellent), 17 in level 4 (good), eight in level 3 (fair), 10 in level 2 (poor), and no patients in level 1 (bad). The average was 4.5, and in 96 patients (84% of all) telediagnosis was accurate (above 4), whereas in 18 patients it was inaccurate (level 2 or 3). In re‐examination of 25 patients, telediagnosis was confirmed in patients in level 4 and 5, whereas heart disease was missed in patients in levels 2 or 3. The correct diagnosis matched the high confidence level of a specialist based on recognizable transmitted images.  相似文献   
998.
999.
We report a case of a 44-year-old woman with bilateral ovarian carcinoma that had metastasized from the colon and mimicked primary mucinous cystadenocarcinoma. Macroscopically, both ovarian tumors were large, multiloculated cystic masses with abundant mucinous content. Histologically, they were lined with mucinous epithelium with mild to moderate nuclear atypia and showed stromal invasion and surface involvement. At first, the tumors were diagnosed as bilateral primary ovarian mucinous cystadenocarcinomas. However, three months after surgery, a large villous tumor was discovered in the ascending colon by colonoscopic examination and was surgically resected. Histologically, the colonic tumor was a villous adenomatous tumor with invasive components of mucinous adenocarcinoma composed of well-differentiated adenocarcinoma and exhibited abundant extracellular mucin production. As a villous adenomatous component was present in the mucosal area, the colonic tumor was considered a primary tumor. Therefore, the original diagnosis of bilateral ovarian tumors was revised for consistent with metastasis from the colon carcinoma, in line with the findings of immunohistochemistry and loss of heterozygosity analysis. This case highlights the importance of considering the possibility of metastatic tumors from the gastrointestinal tract in the diagnosis of mucinous ovarian tumors.  相似文献   
1000.

Objectives

The purpose of this study was to evaluate the application of 15 % propolis and 2 % acidulated-phosphate sodium fluoride solutions on the root surface-adhered necrotic cemental periodontal ligament in delayed tooth replantation.

Materials and methods

Thirty Wistar rats (Rattus norvegicus, albinus) had their right upper incisor extracted and maintained in dry storage for 60 min. After this period, the dental papilla, enamel organ, and pulp tissue were removed, and the animals were randomly assigned to three groups: group I = immersion in saline for 10 min; group II = immersion in a 2 % acidulated-phosphate sodium fluoride solution for 10 min; and group III = immersion in a 15 % propolis and propylene glycol solution for 10 min. The root canals were filled with a calcium hydroxide paste and the teeth were replanted.

Results

Inflammatory resorption, replacement resorption, and ankylosis were observed in all groups without a statistically significant difference (p?>?0.05) among them.

Conclusions

Under the tested conditions, the application of fluoride or propolis on root surface-adhered necrotic periodontal ligament did not favor the healing process in delayed tooth replantation.  相似文献   
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