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991.
BACKGROUND: Allogeneic blood transfusion (ABT) containing packed red blood cells (RBCs) has a known immunosuppressive effect that may affect cancer metastases and recurrence. This study examined whether intraoperative allogeneic RBC transfusion is an independent risk factor of adverse outcome in patients with ampullary carcinoma after curative pancreatoduodenectomy. METHODS: The clinical data of 67 patients with carcinoma of the ampulla of Vatar underwent pancreatoduodenectomy between 1999 and 2004 were analyzed, and long-term follow-up visits were made for all patients. Kaplan-Meier statistics and Cox proportional hazard methodology were used to perform univariate and multivariate analysis to identify independent risk factors for survival. For the meta-analysis, all English-language studies regarding blood transfusion from carcinoma of the ampulla of Vatar or ampullary carcinoma and prognostic factors or factors for survival from 1995 to 2007 were reviewed, and contingency tables were constructed from which a summary relative risk was calculated. RESULTS: There were 43 patients (64.2%) who received an intraoperative ABT. The amount of intraoperative ABT ranged from 2 to 13 (mean, 4.25) units; there were 18 patients transfused at 2 units, and 25 patients transfused >/=3 units. The follow-up ranged from 2 to 90 (mean, 49) months. Forty-five patients (67.2%) died as a result of tumor progression. For patients transfused >/=3 units, median and cumulative 3-year and 5-year survivals were poorer significantly than that of patients transfused with 2 units and/or nontransfused patients (P < 0.05). After multivariate analysis, except for presence of lymph node metastasis (P = 0.023) and pancreatic invasion (P = 0.024), the intraoperative ABT >/=3 units was found to be an independent poor prognostic factor for those with ampullary cancer after curative pancreatoduodenectomy either (relative risk, 2.082; 95% confidence interval (CI), 1.048-4.135; P = 0.036). Meta-analysis of 346 patients showed the summary relative risk of an adverse outcome after intraoperative ABT in these studies was 2.55 (95% CI, 1.59-4.1). CONCLUSIONS: The amount of intraoperative ABT is one of the important factors that adversely influenced survival in patients with ampullary cancer after curative pancreatoduodenectomy. Healing anemia preoperatively and careful dissection to minimize intraoperative bleeding as much as possible are mandatory for reducing risk of the intraoperative ABT.  相似文献   
992.
Each year, approximately 1,000 graduating medical students enter training in general surgery and its related specialties and subspecialties in the United States. Traditionally, residents who want to practice vascular surgery, plastic surgery, thoracic surgery, and other specialties and subspecialties derived from general surgery have been required to complete five years of training in general surgery before embarking on further training. However, three phenomena have recently emerged that are changing the picture of surgical training: (1) proliferation of fellowships in subspecialties of general surgery, (2) increasing desire of subspecialties of general surgery for recognition as specialties in their own right, and (3) pressure to reduce or eliminate the traditional general surgery training required before specialization or subspecialization. In the meantime, and perhaps as a consequence of these changes, traditional general surgery has become less attractive as a specialty and there has been significant concern about the quality of training in general surgery. As a result of fewer trainees electing general surgery as a career, there is now increasing evidence of a shortage of surgeons who are able to handle a reasonably broad caseload of emergency care in general surgery and trauma.Many of these issues are currently being addressed by the profession. Among the initiatives underway are developing a standardized curriculum in general surgery, appropriately apportioning operative experience between residency and fellowship, considering alternative pathways for training in subspecialties, and developing a system for oversight of advanced surgical training fellowships. The system for governance of graduate surgical education in the United States is less centralized than in other countries. One initiative that has been undertaken to improve coordination of efforts between educational and regulatory bodies is the formation of the Surgical Council on Resident Education (SCORE), a voluntary consortium of six organizations with the mission of defining a national curriculum for general surgery residency and with the goal of facilitating collaboration on educational issues involving general surgery and its related specialties and subspecialties.  相似文献   
993.
BACKGROUND: Linitis plastica-type gastric carcinoma remains a disease with poor prognosis despite an aggressive surgical approach. Although a prominent pattern of disease failure is peritoneal carcinomatosis, some patients experience rapid disease progression without signs of the peritoneal disease. METHODS: Clinicopathologic data from 178 patients with linitis plastica-type gastric cancer operated on between 1991 and 2000 were analyzed. Survival stratified by curability of surgery, pN stage, and patterns of failure were evaluated by using the Kaplan-Meier method, and chi(2) test was used to evaluate correlation between the number of metastatic lymph nodes in terms of pN categories and the incidence of various patterns of metastasis and recurrence. Cox regression hazard model was used to identify independent prognostic factors. RESULTS: R0 resection was performed only among 82 patients (46% of those who underwent laparotomy). Node metastasis was frequent with only 22 patients classified as pN0. Peritoneal carcinomatosis was observed in 131 patients and was the commonest pattern of recurrence. Bone metastasis, found in 13 patients, was associated with poor outcome, and its incidence was significantly correlated with the number of metastatic nodes. pT4 status and pN3 status were identified as significant independent prognostic determinants. CONCLUSION: Treatment strategy for the linitis plastica should in general combine surgery with aggressive treatment directed toward peritoneal disease. However, patients with >16 metastatic nodes more often are associated with bone metastasis than those with modest nodal involvement and suffer from poor prognosis.  相似文献   
994.
BACKGROUND: Studies have confirmed adverse outcome associated with transfusion of packed red blood cells (PRBCs) in trauma; however, little data are available regarding other blood product transfusion, such as fresh frozen plasma (FFP) and platelets. The objective of this study was to examine risk-adjusted outcome in trauma with stratification by blood product type. METHODS: Prospective data were collected daily for 1,172 consecutive trauma patients admitted to the intensive care unit (ICU) during a 2-year period, including transfusion rates of blood products (PRBCs, FFP, platelets). Outcome assessment included infection rate, ventilator days (Vdays), ICU and hospital length of stay (LOS), and mortality. RESULTS: Blood products were transfused in 786 (67%) patients. The study cohort had a mean age of 43 +/- 21 years and Injury Severity Score (ISS) of 24 +/- 13. Although the majority of patients were men, women were more likely to be transfused (p < 0.001). Mean transfusion rates of PRBCs (5.5 +/- 9.6 U), FFP (5.4 +/- 11.4), and platelets (3.7 +/- 11.1) were high. Univariate analysis identified that blood product transfusion (any type) was associated with a significantly greater infection rate (34% vs. 9.4%; p < 0.001), hospital LOS (18.6 vs. 9 days; p < 0.001), ICU LOS (13.7 vs. 7.4 days; p < 0.001), Vdays (12.9 vs. 6.3 days; p < 0.001), and mortality (19% vs. 8.3%; p < 0.001). Multivariate analysis (risk-adjusted for severity of injury by ISS, age, sex, and race, and stratified by blood product type) confirmed that risk of infection increased by 5%, and hospital LOS, ICU LOS, and Vdays increased by 0.64, 0.42, and 0.47 days, respectively, for every unit of PRBCs given. Risk of death increased by 3.5% for every unit of FFP transfused. CONCLUSION: There is a dose-dependent correlation between blood product transfusion and adverse outcome (increased mortality and infection) in trauma patients.  相似文献   
995.
The endoscopic endonasal technique is currently used by otolaryngologists for the management of different extradural lesions located below the ethmoidal planum. The cooperation between ENTs and neurosurgeons has recently pushed the use of such approach also in the removal of some intradural lesions, which has promoted the interest for an anatomic study to identify the anatomical landmarks and the dangerous points during the endoscopic approach to this area. In six fresh cadaver heads, unilateral and bilateral measurements between the main landmarks of the approach were performed by means of an endoscopic endonasal approach. A wide exposure of the midline anterior skull base was realized. The maximum of lateral extension was obtained between the two medial orbital walls, at the middle of the cribriform plate (mean distance 25,33 mm), while the mean distance between the anterior and posterior ethmoidal arteries at the level of the lamina papyracea was 16 mm. The endoscopic endonasal route can be considered a minimally invasive technique to approach the ethmoidal planum. It requires adequate anatomical knowledge and endoscopic skill for its realization. Due to the wide window realizable through this corridor, it could be considered in selected cases for the removal of intradural lesions such as meningiomas or estesioneuroblastomas.  相似文献   
996.
Primary distal renal tubular acidosis (dRTA) is an inherited disease characterized by the inability of the distal tubule to lower urine pH <5.50 during systemic acidosis. We report two male siblings who presented with severe hyperchloremic metabolic acidosis, high urinary pH, nephrocalcinosis, growth retardation, sensorineural hearing loss, and hypokalemic paralysis. Laboratory investigations revealed proximal tubular dysfunction (low molecular weight proteinuria, generalized hyperaminoaciduria, hypophosphatemia with hyperphosphaturia, and hypouricemia with hyperuricosuria). There was significant hyperoxaluria and laboratory evidence for mild rhabdomyolysis. Under potassium and alkali therapy, proximal tubular abnormalities, muscular enzymes, and oxaluria normalized. A homozygous mutation in the ATP6V1B1 gene, which is responsible for dRTA with early hearing loss, was detected in both siblings. In conclusion, proximal tubular dysfunction and hyperoxaluria may be found in children with dRTA and are reversible under appropriate therapy.  相似文献   
997.
BACKGROUND: A sol particle homogeneous immunoassay (SPIA) is a method to measure the serum cystatin C (cysC) level as a marker of the glomerular filtration rate (GFR). Recently, formulas to convert measured cysC to GFR have been developed. METHODS: A total of 154 patients (46 +/- 18 years old) who had undergone renal biopsy, sodium thiosulfate clearance (C thio) and 24-h creatinine clearance (24-hCcr) tests were subjects for the study. Their serum cysC levels were determined by SPIA. RESULTS: Multiple regression analysis revealed C (thio) and age as independent variables for serum creatinine concentration (Cr), while only C thio affected cysC. The equations using Cr or cysC showed significant correlation with C thio. Receiver-operating curve ROC analysis revealed that cysC and 24-hCcr shared comparable power to detect patients with GFR < 90 or 60 ml/min/1.73 m2 (AUC = 0.862 and 0.943 vs. AUC = 0.842 and 0.943, respectively), while Cr (AUC = 0.881) and MDRD2 (AUC = 0.888) showed slightly inferior ability to detect 60 ml/min/1.73 m2 than other parameters in the female population. The cut-off point of cysC and Cr obtained from the ROC analysis demonstrated strong power to detect patients with C thio < 90 ml/min/1.73 m2 or C thio < 60 ml/min/1.73 m2. According to CKD stages, the mean values of each equation were significantly different, like that demonstrated by 24-hCcr. CONCLUSION: SPIA could determine cysC levels that detected early renal impairment. The accuracy of cysC to detect early renal impairment may be superior to that of Cr in females, while it would be comparable to that of CG or MDRD when they are corrected by sex and age. Both cysC itself and cysC equations are effective to monitor the progress of renal impairment. The future standardization of cysC measurements and development of novel equation of cysC would contribute to the further improvement of GFR estimation in clinical practice.  相似文献   
998.
Aoki A  Sangawa K 《Surgery today》2008,38(8):751-755
A 73-year-old man with a history of hypertension and drug-induced hepatitis underwent surgical treatment of an enlarging pararenal abdominal aortic aneurysm (PRAAA) with bilateral renal artery stenosis, found on enhanced computed tomography (CT). His preoperative renal function was normal. We divided the right renal artery and used a 6-mm expanded polytetrafluoroethylene (ePTFE) tube graft for the anastomosis. Renal artery perfusion was achieved by a rapid infusion pump set at 200 ml/min. The left renal artery was reconstructed and perfused in the same way. The abdominal aorta was cross-clamped just distal to the superior mesenteric artery and a Y-graft was anastomosed. The ePTFE grafts were connected to the Y-graft and bilateral renal artery circulation was re-established. The renal ischemic time was 1 h 25 min and the urine output during reconstruction was 80 ml. Postoperatively, his serum blood urea nitrogen and serum creatinine levels increased slightly, but normalized within 3 days. This case report shows that this method of renal artery perfusion could prove useful for complex renal artery reconstructions.  相似文献   
999.
PURPOSE: To evaluate the patency and limb-salvage rates associated with cuffed anastomosis in above-knee femoropopliteal (FP) bypasses using prosthetic grafts. METHODS: Between January 1997 and December 2005, 96 patients (99 limbs) underwent above-knee FP bypass grafting for peripheral vascular disease, with disabling claudication in 81%. All grafts were 6-mm, thin-walled, ringed, expanded polytetrafluoroethylene (ePTFE) stretch grafts anastomosed to the above-knee segment of the popliteal artery in an end-to-side fashion, with a protruding area created around the anastomotic toe and an angle of less than 30 degrees between the graft and the artery. Postoperatively, graft patency was monitored by several objective methods. Patency and limb-salvage rates were calculated by actuarial methods and Kaplan-Meier analysis. RESULTS: The mean follow-up period was 40.4 months; 15 patients were lost to follow-up. The 1-, 3-, and 5-year primary graft patency rates were 94.5%, 88.2%, and 85.7%, respectively. The 1-, 3-, and 5-year secondary patency rates were 95.6%, 94.1%, and 90.8%. The 1-, 3-, and 5-year limb-salvage rates were 98.9%, 97.3%, and 97.3%. There were three graft infections. CONCLUSION: The use of a cuffed anastomosis in FP bypass with an ePTFE stretch prosthesis appears to increase graft patency rates.  相似文献   
1000.
BACKGROUND: A retrospective review of 28 patients who had "house flap" anoplasty was carried out to evaluate the therapeutic effectiveness of the procedure. METHODS: House flap anoplasty was performed at Istanbul University Cerrahpasa Medical School, General Surgery Department, in 28 patients over 4 years. Indications were chronic anal fissure, anal stenosis, high transsphincteric fistula, low rectovaginal fistula, anal neoplasia, and obstetric third-degree perineal tear and incontinence. After rectangular excision of the anal or perianal lesion, the "walls" and "roof" of the house flap were incised to the depth of ischiorectal fat. The "base" of this house-shaped flap was then fixed to the top of the excised area. RESULTS: Median postoperative hospital stay was 4.86 (range = 2-12) days. Postoperative complications included three patients with minimal wound dehiscence and one with rectovaginal fistula recurrence. At a median follow-up of 26.4 (range = 1-46) months, excluding the patient with recurrence, all patients were satisfied with house flap anoplasty. CONCLUSION: House advancement flap anoplasty is a relatively simple procedure, combining the beneficial features of rectangular flaps and V-Y plasties. It can be used in nearly all types of anoderm deficiencies with a high rate of success and patient satisfaction.  相似文献   
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