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61.
62.
We describe herein the case of a 51-year-old woman in whom metastatic tumor seeding of the percutaneous transhepatic biliary drainage tract occurred following a pancreatoduodenectomy for carcinoma of the distal common bile, duct. An abdominal computed tomography scan done 6 months after the initial operation detected a hepatic lesion located at the site of the previous percutaneous transhepatic biliary drainage tract. Implantation of bile duct carcinoma in the drainage tract was diagnosed, and the recurrent tumor was successfully resected by performing a subsegmentectomy of segment 3 and removal of the adjacent abdominal wall. At present, 5 years and 4 months after the second resection, the patient is in good health without any signs of recurrence. This case report demonstrates that an aggressive surgical approach should be performed for tumor seeding of a transhepatic biliary catheter tract.  相似文献   
63.
Purpose. To investigate the role of phospholipase A2 (PLA2) in reperfusion injury of the kidney in an in vivo animal model, renal mitochondrial PLA2 activity was measured under three different conditions. Methods. Male Wistar rats (n = 72) anesthetized with pentobarbital underwent renal ischemia surgically for 45 min and were reperfused for the indicated time (renal ischemia/reperfusion). Treatments included reperfusion for various predetermined periods (phase 1), exposure to hyperbaric oxygen (phase 2), and administration of reactive oxygen species (ROS) scavenger (phase 3). Thereafter, each kidney was harvested, and mitochondrial PLA2 activity was measured by a radioisotope technique. Results. Ischemia/reperfusion resulted in time-related PLA2 activation in the renal mitochondria up to 48 h of reperfusion after renal ischemia. Renal mitochondrial PLA2 activity was further augmented by hyperbaric oxygen exposure prior to reperfusion, whereas administration of the ROS scavengers suppressed mitochondrial PLA2 activity. Conclusion. These data suggest that ROS may play an important role in the in vivo activation of PLA2 associated with renal ischemia/reperfusion. Received for publication on July 6, 1998; accepted on November 30, 1998  相似文献   
64.
We present a case of malignant fibrous histiocytoma of the spermatic cord. An 86-year-old man was admitted to the hospital with a right painless scrotal mass. Under the diagnosis of a testicular tumor, right radical orchiectomy was performed. Grossly, the tumor firmly adhered to the spermatic cord. The right testis and epididymis were normal. The histologic diagnosis was malignant fibrous histiocytoma. There was local recurrence 2 months after surgery. The recurrent tumor was resected with the surrounding soft tissue, but the patient died 5 months after the initial operation.  相似文献   
65.
We implanted 60 posterior stabilized total knee prostheses (P.F.C. Sigma, DePuy, Warsaw, USA). In 30 cases, we used a CT-free navigation system (Vector Vision, Brain LAB, Heimstetten, Germany), and in 30 matched-paired controls, we used a conventional manual implantation. We compared postoperative long-leg radiographs in the two groups. The results revealed a significant difference in favor of navigation. In addition, we compared the preoperative anteroposterior dimension of the femoral condyle with the postoperative value. While there were no significant differences in the preoperative anteroposterior dimension of the femoral condyle between the two groups, the postoperative value in the navigation group was significantly larger than that of the preoperative value. Therefore, surgeons using navigation systems should guard against the possibility of oversizing when determining the size of the femoral component.
Résumé Nous avons implanté 60 prothèses totales postéro-stabilisées du genou (P.F.C. Sigma, DePuy). Dans 30 cas nous avons utilisé un système de navigation sans scanner (Vector vision R, Laboratoire du Cerveau, Heimstetten, Allemagne) et dans 30 contrôles appairés nous avons utilisé une implantation manuelle habituelle. Nous avons comparé les grandes radiographies postopératoires des membres inférieurs dans les deux groupes. Les résultats ont révélé une différence notable en faveur de la navigation. De plus nous avons comparé la dimension antéro-postérieure du condyle fémoral avant lintervention avec la valeur postopératoire. Tandis quil ny avait pas de différence notable dans la dimension antéro-postérieure préopératoire du condyle fémoral entre les deux groupes, la valeur postopératoire dans le groupe de la navigation était nettement plus grande que la valeur préopératoire. Par conséquent les chirurgiens qui utilisent des systèmes de navigation doivent prendre garde à ne pas implanter un composant fémoral sur-dimensionné.
  相似文献   
66.
PURPOSE: To determine efficacy, safety, and requirements for adjunctive embolization or surgery in the treatment of symptomatic arteriovenous malformations (AVMs) with superabsorbent polymer microsphere (SAP-MS) particles. MATERIALS AND METHODS: SAP-MS particles (sodium acrylate and vinyl alcohol copolymer) are nonbiodegradable spheres with a precisely calibrated diameter. SAP-MS particles swell by absorbing fluids and become soft and deformable. Twenty-five patients (16 men, nine women; mean age, 32 y; range 12-66 y) with symptomatic facial (n = 5), upper- (n = 8) and lower- (n = 12) extremity AVMs were treated primarily (n = 23) or preoperatively (n = 2) by transarterial embolization (TAE) treatment with use of SAP-MS particles. Direct puncture embolization (DPE; n = 4) and/or surgical intervention (n = 5; ie, skin graft, resection, or amputation) were required. Surgical specimens from the resected (n = 2) and the amputated (n = 2) patients were evaluated histologically. Follow-up study, including clinical findings and imaging studies, was performed at intervals ranging from 3 months to 1 year. Clinical outcome was evaluated retrospectively, depending on the subjective improvement of symptoms and signs, according to the medical records. RESULTS: Seventy-two TAEs (range, 1-11; mean, 2.8) and 12 DPEs (range, 1-3; mean, 2.4) were performed during the mean follow-up period of 38 months (range, 7-110 mo). Twenty patients (80%) experienced symptom improvement by embolotherapy alone (n = 17) or in combination with surgery (n = 3). One lip and two finger AVMs were totally removed by surgical excision or amputation after TAE treatment. In diffuse upper- (n = 1) and lower- (n = 1) extremity AVMs, the symptoms were uncontrolled. No nerve injury or skin necrosis was observed after TAE treatment with SAP-MS particles. Mucosal necrosis was induced by DPE with ethanol in one patient. Histologically, SAP-MS particles penetrated intralesional vessels and conformed to the vessel lumen, resulting in tight vessel occlusion. Minimal perivascular reaction was observed. CONCLUSION: SAP-MS particles were used safely in TAE treatment of AVM. TAE treatment with use of SAP-MS particles was suitable for certain symptomatic AVMs, but diffuse AVMs remain a challenge and a combination of alternative methods will be necessary for further strategy.  相似文献   
67.
BACKGROUND: Initial graft tension influences clinical results of anterior cruciate ligament reconstruction. HYPOTHESIS: Under repetitive loading conditions, the effect of initial graft tension on the biomechanical behavior of the femur-graft-tibia complex may depend on the graft and the fixation. STUDY DESIGN: Ex vivo biomechanical laboratory study. METHODS: After anterior cruciate ligament reconstruction, initial graft tension of 20, 80, or 140 N was applied to the complex for 2 minutes. Then, a cyclic force-relaxation test was performed for 5000 cycles so that the graft was stretched by 2 mm. RESULTS: In a patellar tendon graft with interference screws, the average peak load values at the 5000 th cycle were 105, 157, and 205 N for the complexes with initial tension of 20, 80, and 140 N, respectively. In a flexor tendon graft with interference screws, the values were 27, 41, and 39 N. In a flexor tendon graft with Endobutton fixation, the values were 17, 40, and 77 N. CONCLUSIONS: Considering the tension of the normal anterior cruciate ligament (16 to 87 N), an initial tension of 20 N appears to be high enough for a patellar tendon graft. For a flexor tendon graft with interference screws, an increase in initial tension above 80 N has no biomechanical advantages.  相似文献   
68.
Improvements in image quality and quantitation measurement, and the addition of detailed anatomical structures are important topics for single-photon emission tomography (SPECT). The goal of this study was to develop a practical system enabling both nonuniform attenuation correction and image fusion of SPECT images by means of high-performance X-ray computed tomography (CT). A SPECT system and a helical X-ray CT system were placed next to each other and linked with Ethernet. To avoid positional differences between the SPECT and X-ray CT studies, identical flat patient tables were used for both scans; body distortion was minimized with laser beams from the upper and lateral directions to detect the position of the skin surface. For the raw projection data of SPECT, a scatter correction was performed with the triple energy window method. Image fusion of the X-ray CT and SPECT images was performed automatically by auto-registration of fiducial markers attached to the skin surface. After registration of the X-ray CT and SPECT images, an X-ray CT-derived attenuation map was created with the calibration curve for 99mTc. The SPECT images were then reconstructed with scatter and attenuation correction by means of a maximum likelihood expectation maximization algorithm. This system was evaluated in torso and cylindlical phantoms and in 4 patients referred for myocardial SPECT imaging with Tc-99m tetrofosmin. In the torso phantom study, the SPECT and X-ray CT images overlapped exactly on the computer display. After scatter and attenuation correction, the artifactual activity reduction in the inferior wall of the myocardium improved. Conversely, the incresed activity around the torso surface and the lungs was reduced. In the abdomen, the liver activity, which was originally uniform, had recovered after scatter and attenuation correction processing. The clinical study also showed good overlapping of cardiac and skin surface outlines on the fused SPECT and X-ray CT images. The effectiveness of the scatter and attenuation correction process was similar to that observed in the phantom study. Because the total time required for computer processing was less than 10 minutes, this method of attenuation correction and image fusion for SPECT images is expected to become popular in clinical practice.  相似文献   
69.
Surgical management is the accepted treatment choice for grade III or IV spondylolisthesis, and many satisfactory clinical and radiologic follow-up results have been reported. Very little, however, has been written about long-term results in preteenage patients in whom dysplastic spondylolisthesis has been treated nonoperatively, especially in those who have > or =50% displacement of the fifth lumbar vertebra on the sacrum. We report an unusual case of spontaneous stabilization of severe dysplastic spondylolisthesis in an 8-year-old girl who presented with grade III spondylolisthesis of L5-S1 and was followed up for >14 years in the absence of surgical intervention. On presentation, she complained of a restriction in forward bending and tightness of hamstrings, but she was undisturbed in her daily activities. Initial radiographs showed severe dysplastic spondylolisthesis; however, magnetic resonance imaging (MRI) performed at age 9 years showed that the amount of listhesis was much less than that seen in the initial radiograph. Routine radiographic follow-ups were chosen over early operative measures until she became a teenager. There was no change in the slip, and unusually a gradual ossification of the cartilaginous promontory of the S1 and the posterior lip of the L5 was observed. At 22 years old, the patient is asymptomatic and not conscious of her cosmetic appearance. Surgical treatment has generally been indicated for patients with grade III or IV spondylolisthesis, because slippage progression has been noted in most reported cases. However, MRI may be a tool for predicting which dysplastic spondylolisthesis cases are more likely to progress and therefore circumvent surgical intervention, while maintaining an excellent outcome.  相似文献   
70.
OBJECTIVE: Many phase II trials have shown that preoperative chemotherapy for lung cancer is feasible but associated with postoperative morbidity and mortality. However, little is known about the effect of preoperative chemotherapy on surgical stress and postoperative complications associated with surgical intervention. We evaluated the effect of preoperative chemotherapy on perioperative inflammatory cytokine production as a surgical stress marker. METHODS: The study group comprised 38 patients undergoing anatomical lung resection and mediastinal nodal dissection for clinical stage IB/II non-small cell lung cancer during the period October 2001-December 2003. Nineteen patients received a single cycle of cisplatin (80 mg/m(2)) and docetaxel (60 mg/m(2)) chemotherapy prior to surgery (neoadjuvant group), and 19 patients underwent surgery without any previous chemotherapy (control group). White blood cell and neutrophil counts and serum concentrations of C-reactive protein (CRP), interleukin-6 (IL-6), and granulocyte colony-stimulating factor (GCSF) were determined before surgery and on postoperative days 1 and 3. Postoperative complications were reviewed. Differences were assessed by repeated analysis of variance. RESULTS: Serum concentrations of IL-6 and GCSF rose significantly on postoperative days 1 and 3 in the neoadjuvant group in comparison to concentrations in the control group, but white blood cell count, neutrophil count, and CRP did not differ between the groups. No major complication occurred in either group. CONCLUSIONS: A single cycle of cisplatin and docetaxel chemotherapy followed by surgery can exacerbate overproduction of inflammatory cytokines during the perioperative period in lung cancer patients.  相似文献   
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