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71.

Background

Ewing sarcoma (ES) is the second most common bone tumor in children, and survival of those with metastatic ES has not improved. Previous studies have shown a survival benefit to whole lung irradiation in patients with pulmonary metastases and may be given either before, after, or instead of surgical pulmonary metastasectomy (PM). The contribution of surgery compared with irradiation in ES has not previously been studied.

Methods

A retrospective review of patients younger than 21 years (median age, 16 years) treated at a single institution (1990-2006) was performed. Kaplan-Meier survival curves were compared using log-rank test and a multivariate Cox proportional hazards model. P ≤ .05 was regarded as significant.

Results

Eighty patients with ES were identified. Of these, 31 (39%) had pulmonary metastases. Nine patients had incomplete details of their full treatment regimen, but the following groups could be defined from the remainder: resection alone (n = 5), radiation alone (n = 3), radiation and resection (n = 3), or chemotherapy alone (n = 11). There were 24 deaths overall, with a median overall survival (OS) of 2.7 (95% confidence interval [CI], 1.7-5.2) years. Patients who had PM had the best OS (80%), whereas those who underwent radiation to the lung without PM compared with chemotherapy only for pulmonary metastasis both had similar OS of 0% at 5 years (P = .002). Patients who had radiation followed by PM for lung metastasis had a 5-year OS of 65%. Patients with PM had a longer OS compared with those without lung resection (P < .0001).

Conclusion

These data suggest a possible benefit for ES patients who undergo surgical resection of lung metastases.  相似文献   
72.
Three patients with compound injuries of the lower extremities were treated with pedicle fibular grafts and a free muscle flap concomitantly. There were 1 female and 2 male patients, all of whom sustained high-energy trauma in a motor vehicle accident. The bone defect of the tibia ranged from 8 to 12 cm. The size of the soft-tissue defect ranged from 24 x 15 cm to 28 x 15 cm. All patients underwent preoperative angiography to ensure the patency of the peroneal artery and to avoid its use by risking viability of the leg. All patients were treated with an antegrade-flow pedicle fibular graft. The fibular graft was inserted as a single strut in 2 patients and as a double-barrel strut in 1 patient. The pedicle of the free muscle flap was anastomosed to the distal runoff of the fibular bone flap. All free muscle flap transfers succeeded without complication. Bone scans performed on postoperative day 7 showed viability of transferred bone. The average time to radiological union was 9 months, and the average time to full weight bearing was 12 months. Screw loosening occurred in 2 patients and osteomyelitis was noted in another patient who was treated successfully with sequestrectomy and antibiotics. Indications for this technique are a large segmental bone defect with a huge soft-tissue defect, and patency of the peroneal artery and at least one other major artery. This method provides the advantages of one-stage reconstruction, avoidance of contralateral donor site morbidity, easy control of infection, and chance for early weight bearing. When selected carefully, this technique can be considered when one wants to avoid a two-stage, two free flap transfer.  相似文献   
73.
PURPOSE: Video urodynamic changes were compared after the pubovaginal sling procedure using rectus fascia or polypropylene mesh in women with stress urinary incontinence. MATERIALS AND METHODS: A total of 50 women with various types of stress urinary incontinence were treated with the pubovaginal sling procedure using randomly abdominal rectus fascia in 24 or polypropylene mesh in 26. The sling was placed at the level of the bladder neck and tied with sufficient tension to prevent urinary leakage without obstructing the bladder outlet. Video urodynamics were performed preoperatively, and 7 to 14 days and 3 to 6 months postoperatively in all cases. Surgical results and urodynamic changes after the pubovaginal sling procedure were compared in the 2 groups. Long-term results were evaluated at a mean followup of 2 years. RESULTS: Complete continence was achieved in 23 patients (95.8%) in the rectus fascia group and 26 (100%) in the polypropylene mesh group, including 1 initial failure with reoperation, at a median followup of 24 and 23 months, respectively. The subjective success rate was 91.6% for rectus fascia and 92.3% for polypropylene mesh. The main cause of dissatisfaction was persistent urge incontinence and dysuria in 2 cases each. In each group video urodynamics revealed a mild but nonsignificant decrease in maximum urinary flow and a significant increase in bladder neck opening time at 7 to 14 days versus baseline. However, these parameters returned to baseline within 3 to 6 months postoperatively. Voiding pressure, cystometric capacity and post-void residual urine also showed no significant change in either group after the pubovaginal sling procedure. Patients treated with a polypropylene mesh sling had a shorter operative time and hospital stay, a higher spontaneous voiding rate after catheter removal and a lower incidence of wound pain after surgery. One patient treated with polypropylene mesh had sling margin extrusion. The incidence of new onset detrusor instability and persistent dysuria was similar in the 2 groups. Transrectal sonography of the sling showed that it was located beneath the bladder neck and proximal urethra in all patients in each group. CONCLUSIONS: The results of this study show that the pubovaginal sling procedure using rectus fascia or polypropylene mesh as the sling material had similar effectiveness for treating female stress incontinence but the polypropylene group had more rapid recovery. Postoperatively video urodynamics demonstrated that the pubovaginal sling using either sling material did not cause bladder outlet obstruction with proper surgical technique.  相似文献   
74.
The concept of virtual reality (VR) involves the computer generation of environments with which a user can interact directly. Virtual reality is now being used for medical applications, especially in the area of surgical simulation. As technology advances, VR simulation will play an important training role for both residents and urologists already in practice. This paper examines the history of VR, current developments, and its future implications for the field of urology.  相似文献   
75.
BACKGROUND: This study examined crash severity and injury patterns between helmeted and unhelmeted adolescent motorcycle riders. METHODS: Among an initial population of 4,721 junior college students, 1,284 students were involved in 1,889 motorcycle crashes during a 20-month follow-up period. Crash severity was measured by both the type of collision object and the repair cost of motorcycle damage. RESULTS: The incidence rates of crash, injury, hospitalization, and deaths per 1,000 person-years in the cohort were 358, 104, 14, and 1.3, respectively. Compared with helmeted riders, unhelmeted riders had more noncollisions and fewer collisions with a moving car but there was no significant difference in repair cost of motorcycle damage between these groups. More injuries to the external skin, face, and head and more severe injuries occurred in unhelmeted than in helmeted riders. Among crashes resulting in hospitalization/death, more injuries to the face and head occurred in unhelmeted riders than in helmeted riders. CONCLUSION: Crashes involving unhelmeted riders were not more severe but more frequently involved face and head injuries than crashes involving helmeted riders.  相似文献   
76.

Introduction

Adhesive small bowel obstruction (SBO) is a common postoperative complication. Published data in the pediatric literature characterizing SBO are scant. Furthermore, the relationship between the risk of SBO for a given procedure is not well described. To evaluate these parameters, we reviewed the incidence of SBO after laparoscopic appendectomy (LA) and open appendectomy (OA) performed at our institution.

Methods

With institutional review board approval, all patients that developed SBO after appendectomy for appendicitis from January 1998 to June 2005 were investigated. Hospital records were reviewed to identify the details of their postappendectomy SBO. The incidences of SBO after LA and OA were compared with χ2 analysis using Yates correction.

Results

During the study period, 1105 appendectomies were performed: 477 OAs (8 converted to OA during laparoscopy) and 628 LAs. After OA, 7 (6 perforated appendicitis) patients later developed SBO of which 6 required adhesiolysis. In contrast, a patient with perforated appendicitis developed SBO after LA requiring adhesiolysis (P = .01). The mean time from appendectomy to the development of intestinal obstruction for the entire group was 46 ± 32 days.

Conclusions

The overall risk of SBO after appendectomy in children is low (0.7%) and is significantly related to perforated appendicitis. Small bowel obstruction after LA appears statistically less common than OA. Laparoscopic appendectomy remains our preferred approach for both perforated and nonperforated appendectomy.  相似文献   
77.
We have recently shown that genetic or pharmacological blockade of the melanocortin-4 receptor (MC4-R) attenuates uremia-associated cachexia. However, the potential clinical utility of this approach has been limited by the need to deliver a peptide MC4-R antagonist into the ventricles of the brain. NBI-12i is a recently developed small molecule MC4-R antagonist, with high affinity and selectivity that penetrates the central nervous system after peripheral administration. We tested whether NBI-12i would also be effective in attenuating uremia-associated cachexia in a mouse model. Intraperitoneal administration of NBI-12i stimulated food intake and weight gain in uremic mice. Furthermore, NBI-12i-treated uremic mice gained lean body mass, fat mass, and had a lower basal metabolic rate compared to vehicle-treated and diet-supplemented uremic mice, which lost both lean body mass and fat mass and had an increase in basal metabolic rate. We found that NBI-12i normalizes the expression of uncoupling protein, which is normally upregulated in uremic mice, and we speculate that this may contribute to the drug's protective effect. These data underscore the importance of melanocortin signaling in the pathogenesis of uremia-associated cachexia and demonstrate the potential of peripheral administration of MC4-R antagonists as a novel therapeutic approach.  相似文献   
78.
Takami Y  Russell MB  Gao C  Mi Z  Guo H  Mantyh CR  Kuo PC 《Surgery》2007,142(2):163-169
  相似文献   
79.
80.
The introduction of erythropoiesis‐stimulating agents (ESAs) markedly improved the lives of many anaemic patients with chronic kidney disease (CKD). In Taiwan, the strategy of management of anaemia in patients with CKD was different from many other parts of the world. In 1996, the National Health Insurance Administration of Taiwan applied a more restrictive reimbursement criteria for ESA use in patients with CKD. ESA is to be initiated when non‐dialysis CKD patients have a serum creatinine >6 mg/dL and a hematocrit <28% to maintain a hematocrit level not exceeding 30%. The maximal dose of epoetin‐α or β was 20 000 U per month. The target haemoglobin range and dose limitation for ESAs were the same for dialysis CKD patients. Thus, long before randomized controlled trials showing an increased risk for cardiovascular events at nearly normal haemoglobin concentrations and higher ESA doses in CKD, nephrologists in Taiwan had avoided the use of disproportionately high dosages of ESAs to achieve a haemoglobin level of 10–11 g/dL. Moreover, intravenous iron supplementation was encouraged earlier in Taiwan in 1996, when we reached consensus on the diagnostic criteria for iron deficiency (serum ferritin <300 ng/mL and/or transferrin saturation <30%). The experience of CKD anaemia management in Taiwan demonstrated that a reasonable haemoglobin target can be achieved by using the lowest possible ESA dose and intravenous iron supplementation.  相似文献   
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