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We have developed a technique that enables robotic aortic valve replacement with port access via a small right anterior thoracotomy and minimally invasive aortic cross clamping. The procedure is performed under video guidance with all the annular sutures placed with the robot. In the case we report, the patient's postoperative course was extremely simple and pain was minimal. We believe that this is the first reported aortic valve replacement using robotic technology and that it opens a new field of application for robotic assisted surgery.  相似文献   
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OBJECTIVE: To assess the therapeutic effect of the extent of lymph node dissection performed in patients with a stage pI non-small-cell lung cancer (NSCLC). METHODS: We analysed data on 465 patients with stage I NSCLC who were treated with surgical resection and some form of lymph node sampling. The median number of lymph node sampled was 10 and the median number of ipsilateral mediastinal lymph node stations sampled was two. We chose to define a procedure that harvested 10 or more lymph nodes and sampled two or more ipsilateral mediastinal stations as a lymphadenectomy, by contrast with sampling when one or both criteria were not satisfied. The effect of the surgical techniques: lymph node sampling (LS; n=207) vs. lymphadenectomy (LA; n=258) on 30-day mortality and overall survival were investigated. RESULTS: A total of 6244 lymph nodes was examined, including 4306 mediastinal lymph nodes. The mean (+/-SD) numbers of removed lymph nodes were 7+/-6.1 per patient following LS vs.18.6+/-9.3 following LA (P=0.001). An average mean of 1+/-0.90 mediastinal lymph node station per patient was sampled following LS vs. 2.7+/-0.8 following LA (P<10(-6)). Overall 30-day mortality rates were 2.4 and 3.1%, respectively. LA was disclosed as a favourable prognosticator at multivariate analysis (Hazard Risk: 1.43; 95% Confidence Interval: 1.00-2.04; P=0.048), together with younger patient age, absence of blood vessels invasion, and smaller tumour size. CONCLUSIONS: Importance of lymph node dissection affects patients outcome, while it does not enhance the operative mortality. A minimum of 10 lymph nodes assessed, and two mediastinal stations sampled are suggested as possible pragmatic markers of the quality of lymphadenectomy.  相似文献   
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BACKGROUND: Allografts are occasionally accepted in the absence of immunosuppression. Because naturally occurring CD4(+)CD25(+) regulatory T cells (natural CD25(+) Treg cells) have been shown to inhibit allograft rejection, we investigated their influence on the outcome of allografts in nonimmunosuppressed mouse recipients. METHODS: We compared survival times of male CBA/Ca skin grafts in female CBA/Ca recipients expressing a transgenic anti-HY T-cell receptor on a RAG-1(+/+) (A1[M]RAG+) or a RAG-1(-/-) (A1[M]RAG-) background. Depletion of natural CD25(+) Treg cells in A1[M]RAG+ mice was achieved by in vivo administration of the PC61 monoclonal antibody. The influence of natural CD25(+) Treg cells on the fate of major histocompatibility complex class II-mismatched (C57BL/6X bm12)F1 skin or bm12 heart transplants in C57BL/6 recipients was also assessed. Finally, we investigated the impact of natural CD25(+) Treg cells on the production of T-helper (Th)1 and Th2 cytokines in mixed lymphocyte cultures between C57BL/6 CD4(+) CD25(-) T cells as responders and bm12 or (C57BL/6X bm12)F1 antigen-presenting cells as stimulators. RESULTS: Male allografts were spontaneously accepted by female A1(M)RAG+ mice but readily rejected by female A1(M)RAG+ mice depleted of natural CD25(+) Treg cells by pretreatment with the PC61 monoclonal antibody. Depletion of CD25(+) Treg cells also enhanced eosinophil-determined rejection of (C57BL/6X bm12)F1 skin grafts or bm12 cardiac grafts in C57BL/6 recipients. Finally, natural CD25(+) Treg cells inhibited the production of interleukin (IL)-2, interferon-gamma, IL-5, and IL-13 in mixed lymphocyte culture in a dose-dependent manner. CONCLUSION: Natural CD25(+) Treg cells control Th1- and Th2-type allohelper T-cell responses and thereby influence the fate of allografts in nonimmunosuppressed recipients.  相似文献   
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We report our initial experience with aortic valve replacement using robotic assistance. All procedures were performed with peripheral cardiopulmonary bypass, transthoracic aortic cross-clamp, and antegrade cold crystalloid cardioplegia. One or two ports and a 5-cm intercostal incision in the right chest were used for access. All patients had aortic valve replacement performed robotically. Between February and September 2004, five patients underwent robotic aortic valve replacement. The mean age was 59 years (range 35-82 years). There were no incisional conversions, death, stokes, or reoperations for bleeding. Overall mean study times were as follows: procedure, 231.2 min (range 180-315 min); cardiopulmonary bypass, 121.5 min (range 83-173 min), and cross-clamp, 98.2 min (range 67-140 min). One patient developed postoperative pneumonia. Aortic valve replacement can be successfully performed with the da Vinci robotic system.  相似文献   
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BACKGROUND: Only 2 large (more than 100 patients) prospective trials comparing pancreatogastrostomy (PG) with pancreatojejunostomy (PJ) after pancreatoduodenectomy (PD) have been reported until now. One nonrandomized study showed that there were less pancreatic and digestive tract fistula with PG, whereas the other, a randomized trial from a single high-volume center, found no significant differences between the two techniques. METHODS: Single blind, controlled randomized, multicenter trial. The main endpoint was intra-abdominal complications (IACs). RESULTS: Of 149 randomized patients, 81 underwent PG and 68 PJ. No significant difference was found between the two groups concerning pre- or intraoperative patient characteristics. The rate of patients with one or more IACs was 34% in each group. Twenty-seven patients sustained a pancreatoenteric fistula (18%), 13 in PG (16%; 95% confidence interval [CI] 8-24%) and 14 in PJ (20%; 95% CI 10.5-29.5%). No statistically significant difference was found between the 2 groups concerning the mortality rate (11% overall), the rate of reoperations and/or postoperative interventional radiology drainages (23%), or the length of hospital stay (median 20.5 days). Univariate analysis found the following risk factors: (1) age > or =70 years old, (2) extrapancreatic disease, (3) normal consistency of pancreas, (4) diameter of main pancreatic duct <3 mm, (5) duration of operation >6 hours, and (6) a center effect. Significantly more IAC, pancreatoenteric fistula, and deaths occurred in one center (that included the most patients) (P = .05), but there were significantly more high-risk patients in this center (normal pancreas consistency, extrapancreatic pathology, small pancreatic duct, higher transfusion requirements, and duration of operation >6 hours) compared with the other centers. In multivariate analysis, the center effect disappeared. Independent risk factors included duration of operation >6 hours for IAC and for pancreatoenteric fistula (P = .01), extrapancreatic disease for pancreatoenteric fistulas (P < .04), and age > or =70 years for mortality (P < .02). CONCLUSIONS: The type of pancreatoenteric anastomosis (PJ or PG) after PD does not significantly influence the rate of patients with one or more IAC and/or pancreatic fistula or the severity of complications.  相似文献   
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Abstract:  IGL-1 solution is characterized by inversion of K+ and Na+ concentrations in the University Wisconsin (UW) solution and polyethylene glycol 35 (PEG 35) substitution for hydroxy ethyl starch. In this prospective study, 121 patients transplanted with kidneys preserved in IGL-1 solution were compared to 102 patients grafted with kidneys preserved in UW solution. Serum creatinine and creatinine clearance, delayed graft function (DGF) and rejection episodes, patient and graft survival were evaluated in the first post-transplant year. Groups were comparable regarding to donor and recipient characteristics. Median creatinine levels were significantly lower in IGL-1 group from day 6 to day 14 and it decreased more rapidly in the IGL-1 group (from day 4 to day 15: p < 0.05). Creatinine clearance values were usually higher in the IGL-1 group for the first 15 d. During the follow-up period serum creatinine concentrations were lower in IGL-1 group at one, three, six and 12 months after transplantation (p = 0.04; p = 0.06, p = 0.01 and p = 0.08, respectively) while creatinine clearance values were similar during the follow-up. No significant difference in DGF and rejection rates as well as in patient and graft survival was shown between the two groups. Kidneys preserved in IGL-1 solution showed to have the same function as kidneys preserved in UW solution.  相似文献   
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Introduction An automated procedure for the detection, quantification, localization and statistical mapping of white matter hyperintensities (WMH) on T2-weighted magnetic resonance (MR) images is presented and validated based on the results of a between-centre reproducibility study. Methods The first step is the identification of white matter (WM) tissue using a multispectral (T1, T2, PD) segmentation. In a second step, WMH are identified within the WM tissue by segmenting T2 images, isolating two different classes of WMH voxels – low- and high-contrast WMH voxels, respectively. The reliability of the whole procedure was assessed by applying it to the analysis of two large MR imaging databases (n = 650 and n= 710, respectively) of healthy elderly subjects matched for demographic characteristics. Results Average overall WMH load and spatial distribution were found to be similar in the two samples, (1.81 and 1.79% of the WM volume, respectively). White matter hyperintensity load was found to be significantly associated with both age and high blood pressure, with similar effects in both samples. With specific reference to the 650 subject cohort, we also found that WMH load provided by this automated procedure was significantly associated with visual grading of the severity of WMH, as assessed by a trained neurologist. Conclusion The results show that this method is sensitive, well correlated with semi-quantitative visual rating and highly reproducible.  相似文献   
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BACKGROUND: Many factors are believed to influence the mortality and morbidity after operations for adhesive small bowel obstruction (SBO). METHODS: In a multicenter prospective cohort of 286 patients operated on for adhesive postoperative SBO, we studied the in-hospital and 30-day postdischarge mortality (early mortality) and morbidity as well as long-term mortality using univariate and multivariate analysis. RESULTS: In the present cohort, with a median follow-up of 41 months and 9% patients lost to follow-up at the end of the study, the prevalence of early postoperative mortality was 3%. All deceased patients were over 75 years old with an American Society of Anesthesiologists (ASA) class >/=III. The prevalence of long-term mortality was 7% with the following independent risk factors: age >75 years old (hazards ratio [HR] 6.6 [95% confidence interval [CI], 2.4-18.1]), medical complications (HR 7.4 [CI, 2.2-24.3]), and a mixed mechanism of obstruction (HR 4.5 [CI, 1.5-13.7]). Prevalence of medical and surgical morbidity was 8% and 6%, respectively. Independent risk factors for medical complications were ASA class >/=III (odds ratio [OR] 16.8 [CI, 2.1-133.1]) and bands (OR 14.1 [CI, 1.8-111.5]) and for the surgical complications the number of obstructive structures >/=10 (OR 8.3 [CI, 1.6-19.7]), a nonresected intestinal wall injury (OR 5.3 [CI, 1.5-18.3]), and intestinal necrosis (OR 5.6 [CI, 1.6-19.7]). Otherwise, 3 patients with "apparent" reversible ischemia developed a postoperative intestinal necrosis followed by 2 reoperations and 1 death. CONCLUSION: The early postoperative mortality is strongly linked with the age and the ASA class and the long-term mortality with postoperative complications. More frequent bowel resections might be suggested for patients featuring a number of obstructive structures >/=10 and an intestinal wall injury, especially when associated with a reversible intestinal ischemia.  相似文献   
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