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91.
YY Ho 《Journal of Medical Imaging and Radiation Oncology》2005,49(6):445-459
Bone and soft tissue tumours are rare neoplasms. There are five major roles of imaging in the management of primary musculoskeletal tumours, that is, to differentiate between benignity and malignancy, to evaluate for local tumour extension, to screen for metastases, to judge the effect of chemotherapy, and to monitor for recurrence. To accomplish this, multiple modalities are required because no single examination is able to complete all these tasks. These modalities include plain radiography, CT, MRI, conventional nuclear medicine as well as positron emission tomography (PET) imaging. Elsewhere, PET imaging has been discussed at length, because it is likely to be superior in the assessment of bone and soft tissue tumours over conventional nuclear medicine procedures. However, conventional nuclear medicine may be of value when PET is unavailable. In this review, an overview of anatomical imaging will be given and the role of non‐PET functional imaging will be discussed in detail. A variety of illustrative cases will be presented. 相似文献
92.
93.
E. W. Brien Joseph M. Mirra Steven Kessler M. Suen J. K. S. Ho W. T. Yang 《Skeletal radiology》1997,26(4):246-255
It is not uncommon for sarcomatous transformation of giant cell tumor (GCT) of bone to occur after radiation, but rarely
does malignant transformation occur spontaneously, with less than 15 cases reported up to 1995. Only four of these cases have
been documented in detail. We report two additional cases of GCT of bone spontaneously transforming or ”dedifferentiating”
into osteosarcoma without radiation therapy. The first case is absolutely unique and most interesting in that the dedifferentiation
process occurred in one of multiple GCT lung metastases 6 years after successful eradication of a primary tibial tumor. The
right lung was resected due to development of a large tumor, and at pathologic examination, demonstrated several small nodules
of conventional GCT and a much larger, 14-cm mass composed of a mixture of GCT and high-grade osteosarcoma. The second case
involved a physician, who had a large tumor in the sacrum with vague symptoms for 8 years. Open biopsy revealed conventional,
benign GCT of bone with a secondary aneurysmal bone cyst. Complete curettage 2 weeks later revealed, in addition to areas
of conventional, benign GCT a second component of very high grade osteosarcoma. Both patients died less than 1.5 years from
diagnosis. This report of osteosarcomatous transformation of a conventional GCT of bone strengthens the theory that there
is a mesenchymal cell line in GCT that may spontaneously tansform to sarcoma. 相似文献
94.
Martin Zeier Jolanta Perz Reinhold P Linke Ugo Donini Rüdiger Waldherr Konrad Andrassy Anthony D Ho Hartmut Goldschmidt 《Nephrology, dialysis, transplantation》2003,18(12):2644-2647
BACKGROUND: High-dose chemotherapy followed by autologous blood stem cell transplantation induces remission of plasma cell dyscrasia in patients with AL amyloidosis. The impact of this treatment on the glomerular amyloid mass is still unknown. METHODS: In the present study, the quantity of the renal amyloid mass before and more than 3 years after high-dose melphalan treatment and autologous blood stem cell transplantation was assessed in two patients. At the time of the second renal biopsy, both patients were in complete remission without detectable serum and urinary monoclonal IgA-lambda and a normal percentage of plasma cells in the bone marrow. RESULTS: In both patients with biopsy-proven AL amyloidosis, urinary protein excretion decreased from 7 g/24 h to <2 g/24 h more than 3 years after autologous blood stem cell transplantation. In contrast, glomerular amyloid deposits persisted, as shown in the second biopsy. CONCLUSION: Despite complete remission of the plasma cell dyscrasia and improvement of glomerular permeability, the amount of glomerular amyloid mass did not regress. 相似文献
95.
Aneurysms of the upper extremity 总被引:2,自引:0,他引:2
Thirty aneurysms in the upper extremity in 28 patients over the last 10 years are reviewed. Analysis showed that false aneurysms develop from penetrating trauma, while true aneurysms tend to arise in parts of the arterial tree exposed to blunt trauma. Penetrating injury to vessels should be thoroughly explored and repaired. Arterial aneurysm should be included in the differential diagnosis of masses in the upper extremity, especially after trauma. Three-phase radionuclide scanning is a useful tool for evaluating lesions of the distal arterial tree. When an aneurysm is suspected, early treatment is advised. Treatment options of resection and ligation versus reconstitution of vessel flow should be based on preoperative and intraoperative evaluation of circulatory status. 相似文献
96.
Amir Tejani Ping Leung Ho Lea Emmett Donald M Stablein 《American journal of transplantation》2002,2(2):142-147
Chronic rejection accounted for 32% of all graft losses in 7123 pediatric transplants. In a previous study acute, multiple acute and late acute rejections were risk factors for the development of chronic rejection. We postulated that the recent decrease in acute rejections would translate into a lower risk for chronic rejection among patients with recent transplants. We reviewed our data on patients transplanted from 1995 to 2000, and using multivariate analysis and a proportional hazards model developed risk factors for patients whose grafts had failed due to chronic rejection. A late initial rejection increased the risk of chronic rejection graft failure 3.6-fold (p < 0.001), while a second rejection resulted in further increase of 4.2-fold (p < 0.001). Recipients who received less than 5 mg/kg of cyclosporine at 30 days post-transplant had a relative risk (RR) of 1.9 (p = 0.02). Patients transplanted from 1995 to 2000 had a significantly lower risk (RR = 0.54, p < 0.001) of graft failure from chronic rejection than those who received their transplants earlier (1987-94). Since we were able to demonstrate that there is a decreased risk of chronic rejection graft failure in our study cohort, we would conclude that the goal of future transplants should be to minimize acute rejections. 相似文献
97.
The impact of laparoscopic cholecystectomy on the treatment of symptomatic cholelithiasis 总被引:1,自引:0,他引:1
Background: There has been a debate about the cost-effectiveness of laparoscopic cholecystectomy (LC), as well as a concern regarding its possible overutilization and changes in the indication for surgery.
Methods: A retrospective analysis of all cholecystectomies performed at UCDMC from 1988 to 1994 was done. The annual rate of cholecystectomy increased by 50% in 1990 when LC was introduced but has since stabilized at a rate 11% higher than the rate before LC. The disease status and severity did not change.
Results: The incidence of nonelective surgery remained stable at 31.2% to 37.5%. Elective cholecystectomy had lower mortality (0.16% vs 1.8%, P=0.029), morbidity (2.6% vs 11.2%, P=0.0001), and conversion rate (2.6% vs 16%, P=0.0001) and a shorter length of stay (2.1 days vs 5.4 days), compared with nonelective procedure.
Conclusions: The indication for surgery in cholelithiasis has not changed since the introduction of LC. In patients with symptomatic gallstones, early elective surgery is recommended and may be more cost-effective.Presented at the annual meeting of the Society of American Gastrointestinal Endoscopic Surgeons (SAGES), Orlando, FL, March 12–14, 1995 相似文献
98.
99.
Yun Jeong Lim Young-Ho Kim Geung Hwan Ahn Ho Kwung Chun Woo Young Jang Jun Haeng Lee Hee Jung Son Poong-Lyul Rhee Jae J Kim Seung Woon Paik Byung Chul Yoo Jong Chul Rhee 《Taehan Sohwagi Hakhoe chi》2004,44(6):314-320
BACKGROUND/AIMS: Carcinogenesis is characterized by the abnormal regulation of cell cycle. The abnormal expression of the regulators of cell cycle may be related to the prognosis. Since the clinical significance of the expression of the three proteins in colorectal carcinomas is still controversial, we evaluated the prognostic value of the expression of cyclin E, p27 and mutant p53 in stage II colorectal cancer. METHODS: The expression levels of cyclin E, p27 and mutant p53 proteins in 41 patients with stage II colorectal carcinomas were analyzed by immunohistochemistry. RESULTS: In the univariate analysis, the level of CEA at diagnosis was associated with disease relapse. In the multivariate analysis, the clinicopathological variables such as age, gender, site of primary tumor, tumor size, state of tumor differentiation and preoperative plasma CEA level were not associated with disease relapse. When Kaplan-Meier survival curves were constructed to determine the prognosis, cyclin E, p27 and mutant p53 expressions did not predict poor prognosis. CONCLUSIONS: Our results suggested that the expression of cyclin E, p27 and mutant p53 proteins did not predict the clinical outcome in the stage II colorectal carcinomas. 相似文献
100.