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81.
Purpose To determine the age and gender distribution and imaging features of low-grade central osteosarcoma (LGCOS) of the long bones and pelvis and to discuss our findings in the context of lesions for which LGCOS has been mistaken.Materials and methods We reviewed 99 cases of LGCOS collected between 1919 and 2002 from our institution and pathology consultation files. Adequate imaging was available in 70 cases (36 radiographs only, 17 radiographs/CT, 12 radiographs/MRI, 2 radiographs/CT/MRI, 2 CT only, 1 MRI only, 5 bone scans).Results Patient average age was 30.1±14.2 years, with a slight female predominance. The femur and tibia were the most common long bones involved (29 and 20 each) with the majority of these tumors arising around the knee, followed by the fibula, radius, humerus and ulna (four, three, two and one case each). Flat bones were involved in six cases (three pelvis, one rib, two scapulae). Short tubular bones were involved in five cases (two metatarsal, two phalanges, one clavicle). The lesion extended to the end of the affected long bone in 22 of 59 cases. Lesions were large at presentation (mean 7.9±4.6 cm, range 2–24). Four radiographic patterns were identified: lytic with varying amounts of thick and coarse trabeculation (n=22), predominantly lytic with few thin, incomplete trabecula (n=21), densely sclerotic (n=17) and mixed lytic and sclerotic (n=10). Lesions were benign-appearing overall with focally aggressive features. CT or MRI demonstrated cortical breech or extension into the soft tissues in all cases.Conclusions LGCOS has a variable appearance on radiographs. A frequent pattern is a slow-growing large intracompartmental fibro-osseous lesion with varying amounts of septal ossification associated with focal areas of aggression. A homogeneously sclerotic pattern was also noted. Imaging with CT or MRI was helpful in every instance in our series in identifying areas of soft tissue extension or cortical disruption suggestive of a low-grade malignancy.  相似文献   
82.
European Journal of Orthopaedic Surgery & Traumatology - The goals of this study were to compare patient satisfaction and wound-related complications in patients receiving 2-octyl cyanoacrylate...  相似文献   
83.
OBJECTIVES: To study the morbidity of radical cystectomy and radical radiotherapy in the treatment of patients with invasive carcinoma of the bladder and to report the long-term survival following these treatments. PATIENT AND METHODS: 398 patients with invasive carcinoma of the bladder treated between 1993 and 1996 in the Yorkshire region were studied. Of 398 patients studied, 302 patients received radical radiotherapy and 96 underwent radical cystectomy. A retrospective review of patients' case notes was performed to construct a highly detailed database. Crude estimates of survival differences were derived using Kaplan-Meier methods. Log-rank tests (or, where appropriate, Wilcoxon tests) were used to test for the equality of these survivor functions. These functions were produced as all-cause survival. The proportional hazards regression modelling was used to assess the impact of definitive treatment on survival. A backwards-stepwise approach was used to derive a final predictive model of survival, with likelihood ratio tests to assess the statistical significance of variables to be included in the model. RESULTS: The patients undergoing radiotherapy were significantly older (mean age: 71 years versus 66 years), but no difference was identified in the distribution of American Society of Anaesthesiologists (ASA) grades in the two treatment groups. The stage distribution of cases in the treatment groups was not significantly different. Significant treatment delays were observed in both treatment groups. The median time from being seen in the clinic to transurethral resection of bladder tumour (TURBT) and subsequent radical treatment (cystectomy or radiotherapy) was 4.3 and 9 weeks, respectively. Age was the most significant independent factor accounting for treatment delays (p < 0.001). The 30-day and 3-month treatment-associated mortality for radical cystectomy and radiotherapy was 3.1% and 8.3% and 0.3% and 1.65%. Of the patients who received radiotherapy, 57 (18.8%) were subsequently subjected to a salvage cystectomy. For these 57 patients, 30-day and 3-month mortality after the salvage cystectomy were 8.8% and 15.7%. Gastrointestinal complications were the major source of early morbidity after primary and salvage cystectomy. Bowel leakage occurred in 3% following radical and 8.7% after salvage cystectomy. Bowel complications (leakage and obstruction) were the major cause of death following salvage cystectomy. No specific cause was predominant in those undergoing radical cystectomy with intestinal anastomotic leakage and urinary leakage accounting for one death each. Exacerbation of co-morbid conditions accounted for the remaining causes of mortality. Urinary leakage occurred in 4% following both forms of cystectomy. Recurrent pyelonephritis and intestinal obstruction were responsible for the majority of complications in the follow-up period. Bladder and gastrointestinal complications accounted for the majority of complications following radical radiotherapy. Some degree of irritative bladder and rectal were noted commonly. Severe bladder problems, which rendered the bladder non-functional or required surgical correction, occurred in 6.3% of patients. 2.3% of patients underwent surgery for bowel obstruction related to radiotherapy induced bowel strictures. Following radiotherapy, 43.6% of patients had a recurrence in the bladder at varying intervals post-treatment. Of these, 40% had > or =T2 disease. The 5-year survival following radiotherapy (with or without salvage cystectomy) was 37.4% while 36.5% of patients were alive 5 years after radical cystectomy. There was no statistically significant difference in the overall 5-year survival figures between the two primary treatments. Tumour stage, ASA grade and sex were the only independent predictors of 5-year survival on multivariate analysis. CONCLUSIONS: This retrospective regional study shows that there is no significant difference in the 5-year survival of patients with invasive bladder cancer treated with either radical radiotherapy or radical cystectomy. All forms of radical treatment for bladder cancer are associated with a significant treatment-associated morbidity and mortality. Gastrointestinal complications were responsible for the majority of complications. The treatment-associated mortality at 3 months was two- or three-fold higher than the 30-day mortality; emphasising its importance as an indicator of the true risks of cystectomy. The clinical T stage, the sex and the ASA grade of the patient were the only independent predictors of survival. The data in this series suggests that radical radiotherapy and radical cystectomy should be both considered as valid primary treatment options for the management of invasive bladder cancer.  相似文献   
84.
Evolution of Endpoints for Renal Transplant Outcome   总被引:3,自引:0,他引:3  
Progressive improvement in short-term kidney transplant survival and reduction in acute rejection rates have restricted our ability to assess newer therapy. Past and present conventional endpoints, such as short-term graft survival and acute rejection rates, are no longer practical. This has prompted investigators to search for alternative endpoints. Long-term graft survival is an ideal endpoint. However, this requires a large cohort of patients with longer follow-up. A simpler approach would be to identify short-term markers, which can predict long-term survival. Short-term potential markers that can predict long-term survival are: clinical (renal function), histological (renal pathological markers) and immunological (anti-donor antibody, blood and urine cytokines). Post-transplant renal function estimated by serum creatinine, cystatin C and creatinine clearance within 1 year, and histological indices, as the Banff chronicity score, have the potential to predict long-term graft survival. Serum creatinine is limited as a marker by its variability based on recipient age, body weight, race and sex. Histological indices are limited, due to the invasive nature of evaluation. Post-transplant renal function and histological indices can be used potentially as a composite endpoint, in combination with conventional endpoints, such as graft loss, death and acute rejection. A practical approach for assessing newer therapies in future studies is to use composite endpoints, which combine conventional endpoints (graft loss, death, acute rejection) with newer endpoints (renal function, histological indices).  相似文献   
85.
BACKGROUND: Various techniques for vascular control have been used during urologic laparoscopic procedures. The importance of optimizing the vessel length and securing reliable vascular control are critical for procedures like laparoscopic donor nephrectomy. We aimed to determine the length of vessel lost by using 4 common techniques of vascular control in a fresh human cadaveric vascular model. METHODS: The techniques include application of 2 non-absorbable polymer-ligating clips (10-mm Hem-o-Lok MLX Weck Closure Systems, Research Triangle Park, NC), Endo-GIA II stapler (30-mm length, 2.5-mm staples, Auto Suture, US Surgical, Norwalk, CT), Endopath ETS35 stapler (35 mm length, 2.5mm staples, Ethicon Endo-Surgery), and the Endo Ta-30 stapler (30-mm length, 2.5-mm staples, Auto Suture, US Surgical, Norwalk, CT). RESULTS: The Endo-TA-30 stapler and the polymer clips resulted in significantly less compromise of the vessel length, when compared with the other methods of vascular control. CONCLUSIONS: The Endo-TA-30 stapler and the polymer clips can be applied during laparoscopic procedures where optimizing vascular length is important.  相似文献   
86.
The impact of subclinical inflammation (SCI) noted on early kidney allograft biopsies remains unclear. This study evaluated the outcome of SCI noted on 3‐month biopsy. A total of 273/363 (75%) kidney transplant recipients with a functioning kidney underwent allograft biopsies 3‐months posttransplant. Among those with stable allograft function at 3 months, 200 biopsies that did not meet the Banff criteria for acute rejection were identified. These were Group I: No Inflammation (NI, n = 71) and Group II: Subclinical Inflammation (SCI, n = 129). We evaluated differences in kidney function at 24‐months and allograft histology score at 12‐month biopsy. SCI patients had a higher serum creatinine (1.6 ± 0.7 vs 1.38 ± 0.45; P = .02) at 24‐months posttransplant, and at last follow‐up at a mean of 42.5 months (1.69 ± 0.9 vs 1.46 ± 0.5 mg/dL; P = .027). The allograft chronicity score (ci + ct + cg + cv) at 12‐months posttransplant was higher in the SCI group (2.4 ± 1.35 vs 1.9 ± 1.2; P = .02). The incidence of subsequent rejections within the first year in SCI and NI groups was 24% vs 10%, respectively (P = .015). De novo donor‐specific antibody within 12 months was more prevalent in the SCI group (12/129 vs 1/71, P = .03). SCI is likely not a benign finding and may have long‐term implications for kidney allograft function.  相似文献   
87.
Long‐term success of heart transplantation is hindered by humoral and cell‐mediated immune responses. We studied preexisting antibodies to cardiac self‐antigens, myosin and vimentin, and exosomes induced by antibodies to self‐antigens in eliciting immune responses to cardiac grafts. After syngeneic heterotopic murine heart transplantation, rabbit anti‐myosin or normal rabbit immunoglobulin was administered at day 0 or 7. Sera were collected after heartbeat cessation, cellular infiltration was analyzed, and exosomes were isolated from sera. Histopathologic examination of the controls' transplanted hearts demonstrated normal architecture, and their sera demonstrated neither antibodies to self‐antigens nor exosomes expressing self‐antigens. Administration of antibodies to cardiac myosin immediately posttransplantation (day 0) but not on day 7 triggered graft failure on day 7, and histopathologic examination revealed marked cellular infiltration with neutrophils and lymphocytes. Histopathologic examination of rejected hearts also demonstrated myocyte damage as sera had increased antibodies to myosin and vimentin and development of exosomes expressing self‐antigens. Administration of exosomes isolated from failed grafts containing self‐antigens induced graft dysfunction; exosomes isolated from stable mice did not induce graft failure. Antibodies to self‐antigens can induce exosomes containing self‐antigens, initiating an immune response and causing graft failure after cardiac transplantation.  相似文献   
88.

Background  

Although gastroesophageal reflux disease (GERD) is common in adolescents, the burden of GERD on health-related quality of life (HRQOL) in adolescents has not been previously evaluated. Therefore, the objective of the study was to examine the effect of GERD on HRQOL in adolescents.  相似文献   
89.
Odor learning induces structural and functional modifications throughout the olfactory system, but it is currently unknown whether this plasticity extends to the olfactory receptors (Or) in the sensory periphery. Here, we demonstrate that odor learning induces plasticity in olfactory receptor expression in the honeybee, Apis mellifera. Using quantitative RT‐PCR analysis, we show that six putative floral scent receptors were differentially expressed in the bee antennae depending on the scent environment that the bees experienced. Or151, which we characterized using an in vitro cell expression system as a broadly tuned receptor binding floral odorants such as linalool, and Or11, the specific receptor for the queen pheromone 9‐oxo‐decenoic acid, were significantly down‐regulated after honeybees were conditioned with the respective odorants in an olfactory learning paradigm. Electroantennogram recordings showed that the neural response of the antenna was similarly reduced after odor learning. Long‐term odor memory was essential for inducing these changes, suggesting that the molecular mechanisms involved in olfactory memory also regulate olfactory receptor expression. Our study demonstrates for the first time that olfactory receptor expression is experience‐dependent and modulated by scent conditioning, providing novel insight into how molecular regulation at the periphery contributes to plasticity in the olfactory system.  相似文献   
90.
We describe the clinical presentation, course and pathologic findings found in three adult patients with lipid storage myopathy. Excessive lipid storage was found in Type 1 fibers of muscle. Clinical improvement on oral levo-carnitine therapy suggests the possibility of carnitine deficiency as the most likely etiology in two of the patients and one had mitochondrial myopathy confirmed on genetic analysis.  相似文献   
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