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71.
Purpose  Restorative proctocolectomy has become the most common surgical option for patients with familial adenomatous polyposis (FAP). However, adenomas may develop in the ileal pouch mucosa over time, and even carcinoma in the pouch has been reported. Our aim was to evaluate the prevalence, nature, and etiology of ileal pouch and nonpouch adenomas and carcinoma in patients with FAP. Patients and methods  This was a retrospective study of 31 FAP patients with Kock’s continent ileostomy (Kock; n = 8), ileorectal anastomosis (IRA; n = 7), and ileal pouch–anal anastomosis (IPAA) (n = 16). All patients were followed with a standardized protocol including chromoendoscopy and biopsies of visible polyps in the ileal pouch and nonpouch mucosa. Results  Sixteen of 24 pouch patients (Kock and IPAA) developed adenomas in the ileal pouch mucosa, and all patients with IRA developed adenomas in the rectal mucosa. The prevalence of ileal adenomas was significantly higher in pouch patients than in IRA patients (P = 0.002). Only one patient with Kock showed adenoma in the prepouch area. Two cases of adenocarcinomas and one case of advanced adenoma were found in the ileal pouch mucosa. Conclusion  Our results show a high frequency of adenomas in the ileal pouch mucosa, with evolution into carcinoma in some patients. Regular endoscopic surveillance of the pouch is recommended at a frequency similar to that for the rectal mucosa after IRA in pouch patients with FAP.  相似文献   
72.
Hypertrophic nonunion usually results from insufficient fracture stabilization. Therefore, most hypertrophic nonunions simply require the stabilization of the nonunion site. However, the reasons why union occurs without treating the nonunion site directly is not well understood biologically. In this study, we hypothesized that the intervening tissue at the hypertrophic nonunion site (nonunion tissue) could serve as a reservoir of mesenchymal progenitor cells and investigated whether the cells derived from nonunion tissue had the capacity for multilineage mesenchymal differentiation. After nonunion tissue was obtained, it was cut into strips and cultured. Homogenous fibroblastic adherent cells were obtained. Flow cytometry revealed that the adherent cells were consistently positive for mesenchymal stem cell related markers CD13, CD29, CD44, CD90, CD105, CD166, and negative for the hematopoietic markers CD14, CD34, CD45, and CD133, similar to control bone marrow stromal cells. In the presence of lineage‐specific induction factors, the adherent cells differentiated in vitro into osteogenic, chondrogenic, and adipogenic cells. These results demonstrated for the first time that hypertrophic nonunion tissue contains multilineage mesenchymal progenitor cells. This suggests that hypertrophic nonunion tissue plays an important role during the healing process of hypertrophic nonunion by serving as a reservoir of mesenchymal cells that are capable of transforming into cartilage and bone forming cells. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 27:208–215, 2009  相似文献   
73.
Recently, ischemic mitral regurgitation (IMR) has been shown to be an individual risk factor for ischemic heart disease. The main mechanism of IMR is tethering of the leaflet secondary to left ventricular (LV) dilatation. In this situation, surgical treatment for IMR has been limited to ring annuloplasty with varying degrees of effectiveness. However, mid-term follow-up studies have shown that the results obtained with this approach are not satisfactory. Therefore, there has been a need to develop additional techniques to achieve more secure repair of IMR. The characteristics of the mitral leaflet configuration in IMR are apical displacement of the leaflets relative to the annulus, concavity of the leaflets, and a dilated annulus. Our basic strategy for a tethered mitral valve is rigid ring annuloplasty and inward correction of the outwardly displaced papillary muscle. For the latter correction, we employ the overlapping method or septal anterior ventricular exclusion (SAVE) procedure for LV volume reduction in cases of broad antero-septal infarction, or elevate the posterior papillary muscle by folding the LV wall at the root of the posterior papillary muscle via a small incision in the inferior wall in cases of infero-posterior infarction. An additional procedure is chordal cutting in combination with rigid ring annuloplasty and papillary muscle imbrication in combination with LV volume reduction. We have successfully combined these methods with the aid of detailed echocardiographic studies in individual patients. However, long-term follow-up will be necessary before this approach can be routinely adopted.  相似文献   
74.
We report a case of Sertoli cell tumor. A 33-year-old man visited our clinic with a complaint of painless left scrotal swelling on September 29th, 2003. An elastic firm induration larger than a hen's egg in size was palpable on the surface of the left testis. Tumor markers for testicular tumor such as human chorionic gonadotropin-beta, alpha fetoprotein, and lactate dehydrogenase were not elevated. However, ultrasound showed a low echoic mass in the left testis. Therefore, we performed left high orchiectomy under the diagnosis of left testicular tumor. Its histology showed Sertoli cell tumor. Neither recurrence nor metastasis has been detected for about 8 months after the operation.  相似文献   
75.
Mucinous cystic neoplasms (MCN) of the pancreas are rare tumors that are almost exclusively located in the body or the tail of the pancreas. A 60-year-old woman with no history of pancreatic disease was referred to our hospital with a chief complaint of dull pain in the upper abdomen. Abdominal computed tomography showed a multilocular cystic mass of 7.0 cm in the head of the pancreas, and endoscopic retrograde cholangiopancreatography showed no communication between the cystic mass and the main pancreatic duct. A pancreatoduodenectomy was performed for the complete resection of the tumor, and an annular pancreas was discovered by accident. The pathological examination of the tumor led to a definitive diagnosis of MCN with ovarian-type stroma. To our knowledge this is the first documented case of MCN occurring in the head of the pancreas and associated with annular pancreas.  相似文献   
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78.
We evaluated the usefulness of fluorine-18-fluoro-2-deoxy-d-glucose positron emission tomography (FDG PET) in the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer and then compared the findings with the results of X-ray CT by region based on the histological diagnoses. We examined 29 patients with non-small cell lung cancer. One hundred and thirty-two mediastinal lymph nodes were surgically removed and the histological diagnoses were confirmed. FDG PET images, including 146 mediastinal regions, were visually analysed and the mediastinal lymph nodes were scored as positive when the FDG uptake was higher than that in the other mediastinal structures. On the X-ray CT scans, any mediastinal lymph nodes with a diameter of 10 mm or larger were scored as positive. All three examinations were successfully performed on 71 regions. For FDG PET, we found a sensitivity of 76%, a specificity of 98% and an accuracy of 93%. On the other hand, for X-ray CT a sensitivity of 65%, a specificity of 87% and an accuracy of 82% were observed. A significant difference was observed in respect of both specificity and accuracy (P<0.05). Based on the above findings, FDG PET is suggested to be superior to X-ray CT when used for the detection of mediastinal lymph node metastases in patients with non-small cell lung cancer.  相似文献   
79.
The clinical usefulness of FDG-PET in the prediction and assessment of response to radiation therapy in patients with bronchogenic carcinoma was evaluated. Thirty patients with untreated bronchogenic carcinoma were included in the study. All patients received FDG-PET before the initiation of radiation therapy, while 20 also received it after completing the therapy. The tumor to muscle ratio (TMR) was used as an index of the FDG uptake. The tumor response to therapy was classified as either a partial response (PR, n = 21) or no change (NC, n = 9) according to changes in the tumor size. Prognosis was made 6 months after the initiation of therapy, and was classified as either relapse (n = 19) or non-relapse (n = 9). The FDG uptakes both before and after therapy were compared with tumor response and prognosis. A high FDG uptake was noted in all 30 lesions before therapy. No significant differences in the uptake before therapy was observed according to the histological types nor T factors (UICC). The lesions with a higher uptake (TMR more than 7) responded better to therapy than those with a lower uptake (p < 0.05). The decrease in the uptake after therapy tended to be more prominent in the PR group than in the NC group. The rate of relapse was higher in lesions with a higher uptake before therapy (TMR more than 10) than in those with a lower uptake. The relapse group also showed a higher uptake after therapy than the non-relapse group. In addition, all 6 lesions showing a higher uptake (TMR more than 5) after therapy eventually relapsed (p < 0.05). Two lesions demonstrating a lower uptake both before and after therapy did not relapse, although no tumor regression due to the therapy was observed. These results indicate that FDG-PET plays a complementary role in both predicting and assessing the therapeutic response and prognosis in patients with bronchogenic carcinoma.  相似文献   
80.
A 52-year-old woman was referred to our hospital for treatment of urachal cancer. She complained of supurapubic dull pain and gross hematuria. Computed tomography and magnetic resonance imaging showed a non-papillary sessile tumor, which was located on the dome of the bladder and invaded the small intestine. The tumor was diagnosed as Sheldon's stage IIIC urachal cancer. After three courses of neoadjuvant chemotherapy with FOLFOX4 (oxaliplatin, 5-FU and leukovolin), the tumor was reduced from 7 x 6 cm to 5.5 x 5 cm in size. Consequently, the patient underwent an en-bloc resection of the urachal tumor with the dome of the bladder and the parts of the ileum invaded by the tumor. One course of adjuvant chemotherapy (FOLFOX4) was performed. Surgical specimen revealed histologically well differentiated squamous carcinoma and invasion to the propria of the ileum. The surgical margins were negative for the cancer. For 1.5 years after the surgery, no local recurrence or distant metastasis has been observed.  相似文献   
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