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The objective of this study was to identify risk factors for pancreatic fistula (PF) after stapled transection in distal pancreatectomy (DP). Patients undergoing DP using a stapler for transection between 2005 and 2009 were identified from a pancreatic resection database. Variables examined included patient and tumor characteristics, staple size, and the use of mesh reinforcement. Univariate and multivariate regression analyses were performed to identify risk factors for postoperative PF. One hundred forty-nine had stapled transection, and of these, 25 (17%) had mesh reinforcement. The overall morbidity and mortality rates were 28 per cent and less than 1 per cent; 34 (23%) were diabetic. The rate of clinically significant PF was 14 per cent. On univariate analysis, diabetes (P = 0.04), a firm pancreas (P = 0.03), use of mesh staple line reinforcement (P = 0.02), use of a 4.1-mm staple cartridge (P = 0.01), and blood loss greater than 100 mL (P = 0.01) were associated with higher pancreatic fistula rates. On multivariate analysis, only the presence of diabetes (OR, 4.17; 95% CI, 1.1-15.3; P = 0.03) and the use of a 4.1-mm cartridge (OR, 8.57; 95% CI, 1.2-60.2; P = 0.03) were independently associated with pancreatic fistula formation. Stapled pancreatic transection provides an acceptable PF rate after DP. Diabetes and staple size influence PF rates. In our experience, use of mesh staple line reinforcement did not reduce the incidence of PF after stapled transection.  相似文献   
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Magnetic resonance imaging (MRI) studies of the caudate nucleus have reported reversal asymmetry and alterations of its size, suggesting a striate cortical disorder related to attention-deficit hyperactivity disorder (ADHD). The objective was to evaluate whether alterations of the asymmetry and size of the caudate nucleus head exist in a sample of well-controlled 7- to 11-year-old Colombian children, with different types of ADHD. Two groups of cases-ADHD of the combined type and ADHD of the inattentive type-and one control group, were selected. Multiple methods for assessing ADHD (rating scales, psychologic.interview, neurologic history and examination, and neuropsychologic evaluation) were used to confirm the diagnoses. Participants with a history of language disorder, learning disabilities, depression, and other major neurologic and psychiatric conditions were excluded. Finally all groups had 15 children, matched by sex (7 male, 8 female), age, socioeconomic status, and grade. Height, weight, head circumference, and encephalic index were statistically controlled. Three T1-weighted volumetric (three-dimensional) MRI slides of the caudate nucleus head were obtained with a 1.5-Tesla Gyroscan apparatus. The control group had a significantly higher Wechsler Full-Scale IQ than the groups with ADHD of the combined type and ADHD of the inattentive type (P < .001). Volumes from the left caudate nucleus head were significantly larger than volumes from the right in all groups (P < .001). There were no group differences when volumes were compared between groups. All of the groups had left caudate nucleus head volumes significantly higher than right, although there were no between-group differences. The results in relation to previous studies are discussed.  相似文献   
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To examine the healing of surface defects in articular fractures, gaps measuring 0.5 mm wide and 2 mm deep were created in 0.5-mm coronal step-offs on the medial femoral condyles of 16 rabbits, and identical gaps without step-offs were created in another set of 13 rabbits. Evaluation of repair was done 6, 12, and 24 weeks postoperatively. Histologically, subchondral bone restoration of gaps in step-offs was complete by 24 weeks, whereas restoration was incomplete in most gap-only lesions. Bone density measured by peripheral quantitative computed tomography was normal in gaps in step-offs by 24 weeks, but values were less than in controls in the gap-only group. A moderate degree of degeneration was detected only at the high sides of step-off + gap lesions. The joint surface was restored by fibrous cartilage that showed gradually improving maturity in all defects, however, real integration with adjacent original cartilage did not occur. Immunohistologic examination showed decreasing collagen Type I and increasing Type II staining intensity in repair tissue of both types of lesions. These observations suggest that minor surface gaps and steps of articular fractures may regenerate without inducing severe early joint degeneration. However, certain repair features make the long-term outcome of these defects uncertain.  相似文献   
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OBJECTIVE: The aim of this study was to assess the efficacy, effectiveness, technical difficulty, and clinical usefulness of the popliteal sciatic peripheral nerve block for unilateral hallus valgux surgery and to compare the posterior and lateral approaches. We also aimed to investigate patient comfort during the procedure. MATERIALS AND METHODS: This prospective, randomized trial enrolled 60 patients scheduled for unilateral hallux valgus surgery. The patients were randomly assigned to groups of 30 patients to receive a nerve block by either a posterior or lateral approach. A nerve stimulator was used to locate the response of the two branches forming the sciatic nerve--the posterior tibial nerve and the common peroneal nerve. Then, 20 mL of 0.5% ropivacaine was injected for each nerve. Variables analyzed were efficacy, complications, quality and duration of postoperative analgesia, degree of comfort while the technique was being performed, and level of satisfaction. RESULTS: The level of comfort was good for 19 patients (70%) in the posterior approach group and for 29 (97%) in the lateral approach group (P<0.05). Level of satisfaction was good or very good for 93% and 96% of the patients in the posterior and lateral approach groups, respectively. Block efficacy was excellent for 48 patients (80%), good for 9 (15%), and poor for 3 (5%), with no significant differences between the groups. CONCLUSION: Both the posterior and lateral approaches provide easy access to the sciatic nerve for performing a block. The rate of success is high and postoperative analgesia is good, with no noteworthy complications. However, the lateral approach is more comfortable for the patient.  相似文献   
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Shortening of the radius is observed in Galeazzi (Piedmont) fractures and results from muscle pull after distal radioulnar joint disruption. A cadaver study was designed to examine the normal laxity at the distal radioulnar joint and contributions of the fibrocartilaginous complex (triangular ligament) and the interosseous membrane in prevention of proximal displacement of the distal radius fragment. It was found that up to 5 mm of radial shortening occurred after osteotomy alone. Shortening of over 10 mm did not occur unless both the interosseous ligament and the triangular ligament were sectioned. Some Galeazzi-type fractures may occur in the absence of distal radioulnar joint disruption, and others may result in disruption of the interosseous membrane of the forearm in addition to disruption of the triangular ligament at the wrist. Diaphyseal fractures of the distal radius may occur in several stages of severity. Attempts to produce a Galeazzi lesion by axial loading and pronation of the forearm above the dorsiflexed wrist caused a variety of injuries but did not result in an isolated fracture of the distal radius or disruption of the distal radioulnar joint.  相似文献   
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A 66-year-old woman developed hemodynamic instability, oliguria, prostration, fever, and coagulopathy 4 hours after surgery to replace the femoral stem component of a hip prosthesis under a combined subarachnoid-epidural block. Dyspnea and tachypnea developed, and a petechial rash appeared 24 hours later. The diagnosis was fat embolism after other possible causes were ruled out. Supplementary oxygen, fluid replacement therapy, and inotropic support were started. The patient's condition improved and she was discharged from the postoperative recovery unit 5 days after admission. Although fat embolism usually appears in young men after large bone fractures, it should be considered when symptoms consistent with this diagnosis arise in patients who have undergone orthopedic surgery so that appropriate treatment can be started early.  相似文献   
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