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81.
The following report describes two consecutive brothers from a nonimmigrant family, with no identifiable predisposing factors, who presented with osteosarcomas of their distal femurs, one at the age of 18 years and the other at the age of 21 years. Until a cost-effective program is developed to screen for osteosarcoma, a detailed family history should be obtained from every new patient with osteosarcoma and parents should be urged to schedule early evaluations of siblings with complaints of painful extremities. Increased frequency of cytogenetic studies to screen for genetic abnormalities in patients with osteosarcoma is recommended to help elucidate the cause of osteosarcoma. 相似文献
82.
The effect of adjuvant chemotherapy on osteoarticular allografts 总被引:6,自引:0,他引:6
Hazan EJ Hornicek FJ Tomford W Gebhardt MC Mankin HJ 《Clinical orthopaedics and related research》2001,(385):176-181
Two hundred lower extremity osteoarticular allografts (in 200 patients) performed for aggressive or malignant bone tumors between 1976 and 1997 included 124 grafts of the distal femur, 46 of the proximal tibia, and 30 of the proximal femur. Seventy-four patients did not receive chemotherapy, and 126 received either adjuvant or neoadjuvant therapy. The diagnoses, mean ages, and length of followup were different for the two groups because most of the patients in the chemotherapy group had osteosarcoma, whereas the largest number in the control group had chondrosarcoma or parosteal osteosarcoma. The extent of the surgery was essentially the same for both patient groups, as is reflected by a low recurrence rate (7% for the control and 6% for the chemotherapy group). A statistical comparison of the various parameters showed that the infection, fracture, and amputation rates were the same, but the nonunion rate was markedly increased in the patients who received chemotherapy (32% versus 12%). Cox regression and Kaplan-Meier studies showed that chemotherapy had a significant effect on outcome, with the success rates for the two groups being quite different (72% versus 56%). The results for the distal femur showed a greater effect than for either the proximal tibia or the proximal femur. Analysis of these data suggest the distal femur is perhaps the most prone to healing problems, possibly based in part on the extent of the surgery. A final study supports the concept that the results improved in later years, suggesting a modification or application of the drugs used, better selection of patients, and improvements in surgical technique. 相似文献
83.
Takeshita H Kusuzaki K Murata H Suginoshita T Hirata M Hashiguchi S Ashihara T Gebhardt MC Mankin HJ Hirasawa Y 《British journal of cancer》2000,82(7):1327-1331
A recent study of multidrug resistance (MDR) 1 gene transfected osteosarcoma cells found a cause-effect relationship between increased expression of P-glycoprotein (P-gp) and a low aggressive phenotype. However, several experimental and clinical studies have observed contradictory findings in that P-gp expression has been associated with tumour progression. In the present study, we characterized P-gp-positive and P-gp-negative single-cell clones of a murine osteosarcoma, to further investigate the relationship between P-gp expression and changes in cell phenotype. Although these clones were all selected by doxorubicin (DOX) exposure, they were heterogeneous with respect to MDR1 gene expression. The P-gp-positive clones revealed MDR phenotype, whereas the P-gp-negative clones showed no resistance to drugs. Morphological and functional analysis showed that both the P-gp-positive and P-gp-negative clones were more differentiated than the parent cells in terms of enhanced activity of cellular alkaline phosphatase, an increase in well-organized actin stress fibres and enhanced osteogenic activity. Moreover, these subclones all displayed a decrease in malignant potential such as oncogenic activity, tumour growth rate and metastatic ability, regardless of their P-gp status. These results indicate that the observed osteoblastic differentiation and less aggressive phenotype in DOX-selected osteosarcoma cells may not only be explained by the direct effect of P-gp, and accordingly, consideration of the effect of DOX, as well as P-gp, appears to be important. 相似文献
84.
McLean TW Hertel C Young ML Marcus K Schizer MA Gebhardt M Weinstein HJ Perez-Atayde A Grier HE 《Journal of pediatric hematology/oncology》1999,21(6):486-493
The outcome for 82 pediatric patients with Ewing sarcoma (ES) and primitive neuroectodermal tumor (PNET) of bone is reported; the patients were treated at the Dana-Farber Cancer Institute (DFCI) and Children's Hospital (CH) in Boston, MA (USA) from 1971-1988. The charts of all patients with ES/PNET of bone treated during this period were reviewed for disease status, therapy, sites of relapse, information on second malignancies, and survival status. Eighty-two patients with ES/PNET of bone treated at DFCI/CH were identified. The 10-year event-free survival (EFS) rates were 12% (95% confidence interval [CI] 0, 27%) and 38% (95% CI 26, 51%) for patients with and without metastases, respectively (P = 0.002); the overall survival (OS) rates were 17% (95% CI 1, 33%) and 48% (95% CI 35, 61%) for patients with and without metastases (P = 0.001). Median follow-up for surviving patients is 10.2 years. Primary site in the pelvis also was associated with a poor outcome for patients with no metastatic disease (P = 0.006 OS, P = 0.03 EFS). Thirty-one patients survived in first remission at least 5 years from diagnosis, and of these, five experienced relapse of original disease, and five experienced secondary malignancies. Pediatric patients treated for ES/PNET of bone remain at risk for life-threatening events into the second decade of follow-up. After 5 years, the risk of second malignant neoplasm is at least as high as the risk of late relapse. Prolonged follow-up of patients with ES and PNET of bone is indicated. 相似文献
85.
Steyn PS Gebhardt GS 《European journal of obstetrics, gynecology, and reproductive biology》1999,87(2):167-168
A case report is presented of a 30-year-old woman, gravida 3 para 2, presented with an advanced extra-uterine pregnancy with complete development of the placenta in the fallopian tube. 相似文献
86.
87.
In patients with haemorrhagic necrotizing pancreatitis who are scheduled for surgery we have been carrying out a preoperative retrograde investigation of the pancreatic duct system for the past months. The results in, to date, ten patients revealed four different morphological findings of importance for the surgical tactic: 1. A normal pancreatic duct system with no signs of fistulae: only peripancreatic necrosectomy is required. - 2. Contrast medium leaks via a ductal fistula: left resection including the removal of the fistulous area must be done. - 3. Normal duct system with complete segmental parenchymal staining, representing total necrosis in this region: left resection of the pancreas. - 4. Duodenoscopically demonstrable perforation into the duodenum of a necrotic cavity in the head of the pancreas: conservative management only, no surgery, since this lesion resulting in drainage of the necrotic cavity into the bowel permits self-healing, while the site of the perforation within the necrotic wall cannot be dealt with by surgery. - The experience gained so far indicates that the surgical tactic can be determined with greater selectivity by the use of ERP. 相似文献
88.
89.
Urinary matrix calculi consisting of microfibrillar protein in patients on maintenance hemodialysis 总被引:2,自引:0,他引:2
In seven patients on maintenance hemodialysis, de novo recurrent renal stone formation was observed. In all patients, the underlying disease was glomerulonephritis, with or without the nephrotic syndrome. All patients had considerable persistent proteinuria. The stones consisted predominantly of protein, as revealed by amino acid analysis, and had a negligible carbohydrate and lipid content. Only in some specimens, X-ray diffraction and scanning electron microscopy revealed the presence of small amounts of whewellit (calcium oxalate monohydrate) and/or uric acid. In semithin sections, the stones had a laminated texture and exhibited structural anisotropy under polarized light. With transmission electron microscopy, they were found to consist of peculair microfibrils. The proteinaceous material differed from fibrin or Tamm-Horsfall-protein, as indicated by ultrastructure, carbohydrate analysis, and amino acid analysis. Symptomatic de novo matrix stone formation constitutes another complication of dialyzed patients which has not been reported so far. 相似文献
90.