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Backround  

Diverticulosis is a common disease in the western society with an incidence of 33–66%. 10–25% of these patients will develop diverticulitis. In order to prevent a high-risk acute operation it is advised to perform elective sigmoid resection after two episodes of diverticulitis in the elderly patient or after one episode in the younger (< 50 years) patient. Open sigmoid resection is still the gold standard, but laparoscopic colon resections seem to have certain advantages over open procedures. On the other hand, a double blind investigation has never been performed. The Sigma-trial is designed to evaluate the presumed advantages of laparoscopic over open sigmoid resections in patients with symptomatic diverticulitis.  相似文献   
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Background Neoadjuvant therapy is increasingly used in resectable locally advanced rectal cancer. The exact role of the addition of chemotherapy is not established. We compared neoadjuvant therapy using chemoradiation (CRT) or hyperfractionated accelerated radiotherapy (HART). Methods Clinical, pathological, and survival data were obtained from patients with resectable stage II or III rectal cancer within 7 cm from the anal verge. A group of 50 patients was treated with a preoperative dose of 41.6 Gy of radiotherapy (RT) in two daily fractions of 1.6 Gy over 13 days immediately followed by surgery (HART). A second group of 96 patients received 45 Gy of conventionally fractionated RT in 25 daily fractions of 1.8 Gy combined with 5-fluorouracil–based chemotherapy followed by surgery within 4 to 6 weeks (CRT). Both groups were compared in terms of morbidity, pathological downstaging, local recurrence, and survival. Results Both groups were comparable in terms of preoperative clinicopathological variables. The mean distance from the anal verge was 5.8 cm (HART) versus 4.9 cm (CRT). Sphincter preservation was possible in 74% (HART) versus 83.5% (CRT) of patients (P = .013). The clinical anastomotic leak rate was 2% (HART) versus 2.2% (CRT). Pathological complete response was observed in 4% (HART) versus 18% (CRT) of the resected specimens (P = .002). A pelvic recurrence developed in 6% (HART) versus 4.4% (CRT) of patients (P = .98). Overall 5-year survival was 58% (HART) versus 66% (CRT) (P = .19); disease-free 5-year survival was 51% (HART) versus 62% (CRT) (P = .037). Conclusions Compared with preoperative HART followed by immediate surgery, preoperative CRT followed by a 6-week waiting period enhances pathological response and increases sphincter preservation rate. This could be explained by the addition of chemotherapy or the longer interval between neoadjuvant therapy and surgery. No statistically significant difference was observed in local control or overall survival.  相似文献   
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OBJECTIVES: To describe the results and complications of in situ preservation (ISP) of kidneys from donors after cardiac death (DCD). BACKGROUND: DCD donors are increasingly being used to expand the pool of donor kidneys. ISP reduces warm ischemic injury which is associated with DCD donation. METHODS: Insertion of a double-balloon triple-lumen catheter allows selective perfusion of the abdominal aorta to preserve the kidneys in situ. From January 2001 until August 2005, 133 ISP procedures were initiated in our procurement area. RESULTS: Fifty-six (42%) ISP procedures led to transplantation; in the remaining 77 cases (58%), the donation procedure was abandoned or both kidneys were discarded because of ISP complications (n = 31), poor graft quality (n = 23), no consent for donation (n = 13), medical contraindications (n = 8), or unknown cause (n = 2). Increasing donor age (odds ratio (OR) 1.06 per year, P < 0.001) and uncontrolled DCD donation (OR 5.4, P < 0.001) were independently correlated with ISP complications. After transplantation, prolonged double-balloon triple-lumen catheter insertion time was an independent predictor of graft failure (OR 2.0, P = 0.05). Selected controlled DCD donors were managed by rapid laparotomy and direct aortic cannulation; graft survival of these kidneys was superior to kidneys from controlled DCD donors managed by ISP. CONCLUSIONS: A minority of initiated ISP procedures led to transplantation, resulting in a high workload compared with donation after brain death. The association between increasing catheter insertion time and inferior graft outcome emphasizes the need for fast and effective surgery. Therefore, rapid laparotomy with direct aortic cannulation is preferred over ISP in controlled DCD donation. Despite these limitations, we have expanded our donor pool 3- to 4-fold by procuring DCD kidneys that were preserved in situ.  相似文献   
75.
BACKGROUND: Evidence from animal studies indicate a crucial role for CD25(bright+) regulatory T cells in transplantation tolerance. METHODS: To assess whether peripheral CD25(bright+) T cells control immune responses in immunosuppressed kidney transplant patients, we analyzed the suppressive capacities of these cells using mixed lymphocytes reactions. RESULTS: Allogeneic stimulation of patients peripheral blood mononuclear cells was associated with IL-2 production and T-cell proliferation. Depletion of CD25(bright+) T cells resulted in a 35% (median) higher IL-2 production and a 38% higher proliferative response against third party cells, showing that functional regulatory CD25(bright+) T cells were present (p = 0.03 and 0.02 respectively). In eight out of 11 patients, we also demonstrated regulation activity against donor-activated T cells (p = 0.03). These data were confirmed in coculture experiments with isolated CD25(-/dim) T cells plus CD25(bright+) T cells. At a 1:2 ratio, the CD25(bright+) T cells suppressed the proliferation of CD25(-/dim) donor- and third party-stimulated responder T cells. CONCLUSIONS: CD25(bright+) T cells with immune regulatory activities against anti-donor-responsive T cells are readily detectable in renal allograft recipients during treatment with full dosage immunosuppression. Whether CD25(bright+) T cells indeed play a role in graft acceptance after organ transplantation in patients remains to be elucidated.  相似文献   
76.
BACKGROUND: Most techniques for posterior tibial tendon transfer attach the posterior tibial tendon somewhere at the dorsum of the foot. Inadequate tendon length and difficulties in securing the tendon to bone or tendon can complicate these procedures. Performing the tenodesis proximal to the ankle joint can prevent these problems. The present study is the first to describe the results of posterior tibial tendon transfer through the interosseous membrane attaching only the posterior tibial tendon to the extensor tendons proximal to the ankle joint. METHODS: We examined 13 feet in 12 patients with a foot-drop, equinovarus deformity, or both. The median (range) followup was 3.7 years (9 to 81 months) and the median age at surgery as 30 (13 to 59) years. Evaluation included recording patient satisfaction, use of ankle-foot orthoses (AFO), video-assisted gait analysis, physical examination, the Stanmore system, modified Ninkovi? method, and complications. RESULTS: At followup, patient satisfaction was excellent to good in nine feet. Ten of the 11 feet that needed an AFO preoperatively did not need one after surgery. Gait analysis demonstrated a good to fair gait in 10 patients. Median dorsiflexion was 0 (-25 to 12) degrees, with dorsiflexion to a neutral position or beyond in nine feet. The Stanmore system and modified Ninkovi? method showed excellent to good results in 10 feet. Three complications were recorded including one failed tendon transfer. CONCLUSIONS: Attachment of a split posterior tibial tendon to the extensor tendons proximal to the ankle joint provides results equivalent to other procedures and can be considered a viable operative alternative because it is less difficult and more straightforward than other techniques.  相似文献   
77.
Three-dimensional rotational angiography is capable of exquisite visualization of cerebral blood vessels and their pathophysiology. Unfortunately, images obtained using this modality typically show a small region of interest without exterior landmarks to allow patient-to-image registration, precluding their use for neuronavigation purposes. The aim of this study was to find an alternative technique to enable 3D rotational angiography-guided vascular neurosurgery. Three-dimensional rotational angiograms were obtained in an angiographic suite with direct navigation capabilities. After image acquisition, a navigated pointer was used to touch fiducial positions on the patient's head. These positions were located outside the image volume but could nevertheless be transformed into image coordinates and stored in the navigation system. Prior to surgery, the data set was transferred to the navigation system in the operating room, and the same fiducial positions were touched again to complete the patient-to-image registration. This technique was tested on a Perspex phantom representing the cerebral vascular tree and on two patients with an intracranial aneurysm. In both the phantom and patients, the neuronavigation system provided 3D images representing the vascular tree in its correct orientation, that is, the orientation seen by the neurosurgeon through the microscope. In one patient, tissue shift was clearly observed without significant changes in the orientation of the structures. Results in this study demonstrate the feasibility of using 3D rotational angiography data sets for neuronavigation purposes. Determining the benefit of this type of navigation should be the subject of future studies.  相似文献   
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The aim of this cross‐sectional study was to analyze the incidence of incisional hernia after liver transplantation (LT), to determine potential risk factors for their development, and to assess their impact on health‐related quality of life (HRQoL). Patients who underwent LT through a J‐shaped incision with a minimum follow‐up of three months were included. Follow‐up was conducted at the outpatient clinic. Short Form 36 (SF‐36) and body image questionnaire (BIQ) were used for the assessment of HRQoL. A total of 140 patients was evaluated. The mean follow‐up period was 33 (SD 20) months. Sixty patients (43%) were diagnosed with an incisional hernia. Multivariate analysis revealed surgical site infection (OR 5.27, p = 0.001), advanced age (OR 1.05, p = 0.003), and prolonged ICU stay (OR 1.54, p = 0.022) to be independent risk factors for development of incisional hernia after LT. Patients with an incisional hernia experienced significantly diminished HRQoL with respect to physical, social, and mental aspects. In conclusion, patients who undergo LT exhibit a high incidence of incisional hernia, which has a considerable impact on HRQoL. Development of incisional hernia was shown to be related to surgical site infection, advanced age, and prolonged ICU stay.  相似文献   
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