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81.
We report a case of a 33-year old man who presented with symptoms and signs of an acute biliary tract obstruction with jaundice and abdominal pain. Diagnostic imaging studies revealed a biliary stricture of the hepatic confluence, and a mass at the hepatic hilum which obstructed the extrahepatic bile duct from the outside. At laparotomy, there was 3-cm-size nodule at the hilum which presented with a rubbery consistency. We performed extrahepatic bile duct resection and right and left hepaticojejunostomy. Histological examination of the resected specimen revealed follicular lymphoma, which consisted of medium cleaved follicle-like cells, grade 1 of 3 according to the revised European-American classification of lymphoid neoplasms proposed by International Lymphoma Study Group. Postoperative follow-up of more than 1 year has been completely uneventful, without any symptoms or signs of disease recurrence. This is the second case report of follicular lymphoma of the extrahepatic bile duct.  相似文献   
82.
In contrast to malignant lymphomas or skin cancer, smooth muscle tumors including leiomyosarcoma are rarely associated with transplant recipients. We herein present a 33-year-old woman with end-stage renal disease who received a transplant at 27 years of age. Four years after the transplantation, at age 31, she underwent a mastectomy because of primary right breast cancer, which was found to be a 5-mm-sized mucinous carcinoma with no regional lymph node metastasis. Six years after the transplantation, a liver tumor was unexpectedly discovered. An explorative laparotomy revealed a well-encapsulated tumor occupying the posterior portion of the right lobe of the liver. The patient underwent a posterior segmentectomy. Histologically, the tumor possessed intermingling fascicles of spindle cells with eosinophilic cytoplasm and elongated nuclei. Based on an immunohistochemical examination, the tumor cells were positive for the muscle-associated antibody. In addition, RNA probes for Epstein-Barr virus were negative based on in situ hybridization. The histologic, immunohistochemical findings were considered to be diagnostic for leiomyosarcoma, which is a low-grade malignancy. Two years after surgery, the patient is doing well with no recurrence of liver tumors or breast cancer. Received: April 16, 2001 / Accepted: September 11, 2001  相似文献   
83.
Tamori Y  Masugi J  Nishino N  Kasuga M 《Diabetes》2002,51(7):2045-2055
Peroxisome proliferator-activated receptor (PPAR)-gamma plays an important role in adipogenesis. However, the functions of PPAR-gamma in differentiated adipocytes have remained unclear. The role of PPAR-gamma in mature 3T3-L1 adipocytes was therefore investigated by overexpression of a dominant negative mutant of this protein (PPAR-gamma-DeltaC) that lacks the 16 COOH-terminal amino acids and that has been shown to prevent the thiazolidinedione-induced differentiation of 3T3-L1 cells into adipocytes. Overexpression of PPAR-gamma-DeltaC in mature 3T3-L1 adipocytes by adenovirus gene transfer resulted in a decrease in both cell size and intracellular triglyceride content, an increase in the extent of lipolysis, and a reduction in the rate of free fatty acid uptake. Furthermore, overexpression of this mutant reduced the abundance of mRNAs for several key enzymes that contribute to triglyceride and free fatty acid metabolism as well as the amounts of GLUT4, insulin receptor, insulin receptor substrate (IRS), and C/EBPalpha mRNAs. It also reduced both the concentration of IRS2 and the insulin-stimulated glucose uptake. These results suggest that PPAR-gamma plays an important role in mature 3T3-L1 adipocytes at least in part by maintaining the expression of genes that confer the characteristics of mature adipocytes.  相似文献   
84.
BACKGROUND: The objective of this study was to evaluate the clinical outcome after surgical management of renal cell carcinoma (RCC) extending to the inferior vena cava (IVC). METHODS: This study included a total of 55 patients (41 men and 14 women; mean age, 59.3 years) with RCC (39 right- and 16 left-sided tumors) involving the IVC, who underwent radical nephrectomy and tumor thrombectomy between 1983 and 2005 at a single institution in Japan. The level of thrombus was classified as follows: level I, infrahepatic; level II, intrahepatic; level III, suprahepatic; and level IV, extending to the atrium. Clinicopathological data from these patients were retrospectively reviewed to identify factors associated with survival. RESULTS: There were 11 and 18 patients who were diagnosed as having lymph node and distant metastases, respectively. Twenty-two patients had tumor thrombus in level I, 20 in level II, 10 in level III, and 3 in level IV. Pathological examinations demonstrated that 34 and 21 patients had clear cell carcinoma and non-clear cell carcinoma, respectively, 42, 9 and 4 were pT3b, pT3c and pT4, respectively, and 6, 35 and 14 were Grades 1, 2 and 3, respectively. Cancer-specific 1-, 3- and 5-year survival rates of these 55 patients were 74.5%, 51.4% and 30.3%, respectively. Among several factors examined, clinical stage (P = 0.047), lymph node metastasis (P = 0.016), histological subtype (P = 0.034) and tumor grade (P < 0.001) were significantly associated with cancer-specific survival by univariate analysis. Furthermore, multivariate analysis demonstrated clinical stage (P = 0.037) and tumor grade (P < 0.001) as independent predictors of cancer-specific survival irrespective of other significant factors identified by univariate analysis. CONCLUSIONS: In patients with RCC involving the IVC, biological aggressiveness characterized by tumor grade rather than tumor extension would have more potential prognostic importance; therefore, more intensive multimodal therapy should be considered in patients with high grade RCC with tumor thrombus extending into the IVC.  相似文献   
85.
STUDY DESIGN: A human cadaveric biomechanical study of fixation strength of an improved novel pedicle screw (NPS) with cement and a conventional screw. OBJECTIVE: To clarify whether the NPS has adequate fixation strength without leakage in vertebrae with low bone quality. SUMMARY OF BACKGROUND DATA: The fixation strength of pedicle screws decreases in frail spines of elderly osteoporotic patients. Augmentation of screw fixation with bone cement must be balanced against increased difficulty of screw removal and risk of cement leakage. We developed the NPS consisting of an internal screw and an outer sheath to mitigate the disadvantages of cement augmentation. METHODS: The T12 and L1 vertebrae obtained from 18 formalin preserved cadavers (11 males and 7 females; mean age, 82.7 y) were used. The mean bone mineral density was 0.39 +/- 0.14 g/cm2. The NPS was inserted into one pedicle of each vertebra and the control screw, a Compact CD2 screw, was inserted into the contralateral pedicle. Both screws were 6mm in diameter and 40 mm in length. Pull-out tests were performed at a crosshead speed of 10 mm/min. Cyclic loading tests were performed with a maximum 250 N load at 2 Hz until 30,000 cycles. RESULTS: Cement leakage did not occur in any of the specimens tested. The mean maximum force at pull-out was 760 +/- 344 N for the NPS and 346 +/- 172N for the control screw (P < 0.01). Loosening of 50% of the screws was observed after 17,000 cycles of the NPS and after 30 cycles of the control screw. The hazard ratio of loosening was 19.6 (95% confidence interval 19.3-19.9) (P < 0.001). CONCLUSIONS: The NPS showed a significantly higher mechanical strength than the control screw in both pull-out tests and cyclic loading tests. The NPS showed more than adequate strength without cement leakage.  相似文献   
86.
The intracardiac growth and extension of liposarcoma was observed in a 60-year-old woman. The epicardial tumor was identified to originate from the anterior wall of the right ventricle. She initially showed symptoms associated with cardiac tamponade. A surgical operation was performed but it resulted in incomplete resection due to massive invasion and dissemination. The recurrence of the tumors led to congestive heart failure. Finally, she died of heart failure and liver dysfunction as a result of tumor metastasis and invasion. An autopsy detected the primary cardiac liposarcoma. Only a few cases of cardiogenic liposarcoma have so far been reported. A further elucidation of cardiac liposarcoma could reveal mechanisms of the disease, and thus contribute to development of complementary therapies after surgical intervention.  相似文献   
87.
Diagnostic and therapeutic strategies for acute biliary inflammation/infection (acute cholangitis and acute cholecystitis), according to severity grade, have not yet been established in the world. Therefore we formulated flowcharts for the management of acute biliary inflammation/infection in accordance with severity grade. For mild (grade I) acute cholangitis, medical treatment may be sufficient/appropriate. For moderate (grade II) acute cholangitis, early biliary drainage should be performed. For severe (grade III) acute cholangitis, appropriate organ support such as ventilatory/circulatory management is required. After hemodynamic stabilization is achieved, urgent endoscopic or percutaneous transhepatic biliary drainage should be performed. For patients with acute cholangitis of any grade of severity, treatment for the underlying etiology, including endoscopic, percutaneous, or surgical treatment should be performed after the patient's general condition has improved. For patients with mild (grade I) cholecystitis, early laparoscopic cholecystectomy is the preferred treatment. For patients with moderate (grade II) acute cholecystitis, early laparoscopic or open cholecystectomy is preferred. In patients with extensive local inflammation, elective cholecystectomy is recommended after initial management with percutaneous gallbladder drainage and/or cholecystostomy. For the patient with severe (grade III) acute cholecystitis, multiorgan support is a critical part of management. Biliary peritonitis due to perforation of the gallbladder is an indication for urgent cholecystectomy and/or drainage. Delayed elective cholecystectomy may be performed after initial treatment with gallbladder drainage and improvement of the patient's general medical condition.  相似文献   
88.
Introduction Flat foot and/or metatarsal primus varus are the major causes of hallux valgus, and it is important to correct these deformities in order to prevent the recurrence of this condition. We demonstrate the clinical and radiological assessment of the correction of hallux valgus, metatarsal primus varus, and flat foot after proximal oblique-domed osteotomy of the metatarsus with distal soft tissue reconstruction. Materials and methods Twenty-seven feet of 22 patients with moderate or severe hallux valgus who had undergone proximal oblique-domed osteotomy were studied. After the adductor hallucis tendon was cut at the attachment of the proximal phalanx and at the sesamoid bone, the osteotomy was performed 3 cm dorsal-distal to the metatarsocuneiform joint to transfer distal fragment approximately 5 mm in the plantar direction, and rotated laterally decreasing the first–second intermetatarsal angle to 5 degrees. Results The mean AOFAS score was 54.1 ± 2.8 points at pre-operation and 92.8 ± 4.8 points at the most recent follow-up (P < 0.0001). Significant improvement was seen between the hallux valgus angle (P < 0.0001), first–second intermetatarsal angle (P < 0.0001), first–fifth intermetatarsal angle (P < 0.0001), talar pitch (P = 0.0032), and calcaneal plantar angle (P = 0.0327) before surgery and at one year after surgery. The average improvement of the talar pitch and calcaneal plantar angle was 2.6 ± 1.4 and 2.4 ± 1.5 degrees, respectively. Conclusion This study suggest that proximal oblique-domed osteotomy of the metatarsal as a surgical procedure for the treatment of moderate or severe hallux valgus with flat foot can be recommended to correct the longitudinal arch of the foot and the first–second intermetatarsal angle.  相似文献   
89.
Malignant fibrous histiocytoma (MFH) of the lung is rare, accounting for less than 0.2% of all pulmonary neoplasms, and an optimal treatment strategy has not yet been elucidated. We encountered a 62-year-old male patient with MFH of the lung who underwent a resection of the lymph node of recurrence 7 months after a lobectomy. We herein review 93 cases of pulmonary MFH in the literature, and discuss the surgical treatment for this disorder with special reference to lymph node involvement. Lymphogenic metastasis was observed in 14 of 72 cases (19%) who underwent surgical treatment. The 5-year survival rates for these reported patients with and without surgical treatment were 43% and 0% (P = 0.01) and the 5-year survival rates for “resected” patients with and without lymph node metastasis were 27% and 49%, respectively (P = 0.03). A complete resection with the systematic dissection of regional lymph nodes is therefore considered to positively contribute to the survival of patients with primary pulmonary MFH.  相似文献   
90.
Background There has been a trend toward minimally invasive treatment of early gastric cancer. We report the preliminary results of laparoscopy-assisted distal gastrectomy with laparoscopic sentinel lymph node biopsy after endoscopic mucosal resection. Methods Six patients underwent laparoscopy-assisted distal gastrectomy after endoscopic mucosal resection between February 2002 and October 2005 at Mie University Hospital. These patients first underwent laparoscopic sentinel lymph node biopsy and then laparoscopy-assisted distal gastrectomy with lymphadenectomy. Results No patient underwent conversion to open surgery during the operation. None of the patients had any postoperative complications. The mean length of postoperative hospital stay was 11.3 days. Sentinel lymph nodes were identified laparoscopically in five patients. There were 20 sentinel and 85 nonsentinel lymph nodes in the six patients. Postoperatively, tissue sections showed that none of the lymph nodes were metastasized. Immunohistochemistry with D2-40 antibody showed that there were normal lymphatics in the submucosal layer with mucosal defects at the endoscopic mucosal resection site. No patients had any tumor recurrence during followup. Conclusions Laparoscopy-assisted distal gastrectomy after endoscopic mucosal resection was a safe and curative procedure. Endoscopic mucosal resection before sentinel lymph node biopsy was acceptable for early gastric cancer.  相似文献   
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