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51.
Abstract. Background/Purpose: Although curative surgical resection provides the best chance of long-term survival for patients with intrahepatic cholangiocarcinoma, the presence of bile duct invasion decreases postoperative survival rates in patients with mass-forming intrahepatic cholangiocarcinoma. We carried out this study to determine a surgical strategy for patients with bile duct invasion of these tumors. Methods: Forty-one patients with mass-forming intrahepatic cholangiocarcinoma were classified as either having bile duct invasion (n= 26) or not having bile duct invasion (n= 15). Clinicopathologic findings, including postoperative outcomes, were compared between these two groups. Results: Perineural invasion, lymphatic invasion, and a positive resection margin were more frequent in patients with ductal invasion. Patients with ductal invasion had lower survival rates than those without ductal invasion. Conclusions: Intraoperative frozen section examination of the bile duct stump to confirm a clear resection margin is required in patients with mass-forming tumors. Resection of the extrahepatic bile duct should be considered when tumor cells are identified at the surgical margin of the resected bile duct. Received: October 30, 2001 / accepted: November 16, 2001  相似文献   
52.
Anastomotic insufficiency is considered to be one of the most serious complications associated with esophageal reconstruction. The purposes of this study were to identify (1) the relationship between anastomotic insufficiency and tissue blood flow (TBF) in the gastric tube in the perioperative period, and (2) the effects of intravenous prostaglandin E1 (PGE1) on TBF in the gastric tube. The study group consisted of 44 patients who were to undergo esophagectomy for esophageal cancer. Intraoperative and postoperative TBF on the serosal side of the gastric tube were measured by laser-Doppler tissue blood flowmetry. The TBF of the Leakage(+) group (n = 5) was poorer than that of the Leakage(?) group (n = 39) during the intraoperative and postoperative periods. There was a significant difference in TBF between the two groups at postoperative day (POD) 3. There was a tendency in the PGE1(+) group (n = 18) to exhibit richer blood flow through the anastomosis than the PGE1(?) group (n = 26), intraoperatively, but the difference was not significant. Two of five Leakage(+) cases were also in the PGE1(+) group. There was no relationship between intraoperative medication with PGE1 and incidence of leakage. The TBF of three-field lymph node dissection and reconstruction of the retrosternal route group (n = 21) was poorer than that of the two-field lymph-node dissection and reconstruction of the posterior mediastinal route group (n = 23). The TBF in the gastric tube after esophagectomy may be a predictor of anastomotic insufficiency. However, PGE1 treatment in the intraoperative period alone is not effective in preventing anastomotic insufficiency.  相似文献   
53.
Recent clinical and experimental studies have shown that aldosterone is a potent inducer of proteinuria and that mineralocorticoid receptor (MR) antagonists confer efficient antiproteinuric effects. We identified glomerular epithelial cells (podocytes) as novel targets of aldosterone; activation of MR injures podocytes possibly via oxidative stress, resulting in disruption of glomerular filtration barrier, proteinuria, and progression of chronic kidney disease. We also demonstrated that SHR/cp, a rat model of metabolic syndrome, was susceptible to podocyte injury and proteinuria. Aldosterone excess caused by adipocyte-derived aldosterone-releasing factors was suggested to underlie the nephropathy. High salt intake augmented MR activation in the kidney and exacerbated the nephropathy. Furthermore, we identified an alternative pathway of MR activation by small GTPase Rac1. RhoGDIα knockout mice, a model with Rac1 activation in the kidney, showed albuminuria, podocyte injury, and glomerulosclerosis. Renal injury in the knockout mice was accompanied by enhanced MR signaling in the kidney despite normoaldosteronemia, and was ameliorated by an MR antagonist, eplerenone. Moreover, Rac-specific inhibitor significantly reduced the nephropathy, concomitantly with repression of MR activation. In vitro transfection studies provided direct evidence of Rac1-mediated MR activation. In conclusion, our findings suggest that MR activation plays a pivotal role in the pathogenesis of chronic kidney disease in metabolic syndrome, and that MR may be activated both aldosterone dependently (via aldosterone-releasing factors) and independently (via Rac1). MR antagonists are promising antiproteinuric drugs in metabolic syndrome, although long-term effects on renal outcomes, mortality, and safety need to be established.  相似文献   
54.
A 41-year-old Chinese woman was admitted to our hospital with epigastric pain. Computed tomography detected a heterogeneous enhancement tumor fed by the left gastroepiploic artery in the left lower quadrant and cholelithiasis. Excision of the tumor in the greater omentum and cholecystectomy were performed laparoscopically. Histological findings confirmed a diagnosis of hemangiopericytoma with low-grade malignancy. To our knowledge, hemangiopericytoma of the greater omentum is very rare, and only 12 cases were reported in English literature. We report a case of hemangiopericytoma arising in the greater omentum and review the literature.  相似文献   
55.
Background We have developed a new technique for treatment of intramucosal carcinoma which exceeds the standard indication for endoscopic mucosal resection and carcinoma invading the submucosa without lymph node metastasis that are located in the posterior wall of the stomach, which we refer to as laparoscopic intragastric full-thickness excision (LIFE) under flexible endoscopic control. Surgical Technique Three pigs were used for the study. Three trocars were used. The first trocar (trocar # 1) was placed in the subumbilical region to introduce the videoscope, whereas the second and third trocars (trocar # 2 and trocar # 3) were punctured percutaneously into the abdominal cavity. A straight needle with 3-0 silk suture was attached to a T-bar on the wire side and inserted into the abdominal cavity. An area adjacent to the lesion in the posterior wall of the stomach was pierced by the straight needle, which was then pulled into the stomach using the forceps of the endoscope. The T-bar, after being passed through the abdominal wall, was fixed outside the gastric wall, and trocar # 3 was repositioned in the stomach by the percutaneous transgastric route. The posterior wall of the stomach was pulled inward by the T-bar, and the lesion was removed by several excisions with laparoscopic stapling devices inserted through trocar # 3; extraction of the specimen was achieved through trocar # 3. The gastrotomy site was suture-closed using instruments positioned through trocar # 2 and trocar # 3 under laparoscopy. Conclusions Based on a feasibility study in pigs, the LIFE procedure can be performed for lesions of the posterior wall of the stomach.  相似文献   
56.
We report two cases of aortic valve replacement (AVR) for severe aortic stenosis (AS) before the cancer operations. Severe AS poses a great risk for noncardiac surgery. In the ACC/AHA 2007 Guideline on Perioperative Cardiovascular Evaluation and Care for Noncardiac Surgery, if the AS is symptomatic, elective noncardiac surgery should generally be postponed or canceled. Such patients require AVR before elective noncardiac surgery. On the other hand, in patients with severe AS who refuse cardiac surgery, noncardiac surgery can be performed with a mortality risk of approximately 10%. In our cases, severe AS was found in the preoperative examination. We informed them about necessary AVR before noncardiac surgery, and patients consented to our suggestion. AVR was performed around 7 days after this consent, and cancer operation was performed around 30 days after the AVR. However, there are no clear guidelines for this interval between AVR and cancer operation. In our cases the patients underwent the cardiac surgery and noncardiac surgery in a short period without serious complication in the perioperative management. It is very important to discuss among surgeon, cardiovascular surgeon, cardiologist and anesthesiologist. Especially anesthesiologist should take an important role in organizing these departments for such patients.  相似文献   
57.

Purpose  

Gastrojejunostomy is often performed as palliative surgery for unresectable pancreatobiliary cancer. Modified Devine exclusion (MDE) is a technical variation of gastrojejunostomy, which partially separates the mid-portion of the stomach. We conducted this study to assess whether MDE is necessary for gastrojejunostomy in patients with unresectable pancreatobiliary cancer.  相似文献   
58.
A 56-year-old female who had been diagnosed with Ebstein's anomaly was admitted with cyanosis and congestive heart failure. The echocardiogram showed severe tricuspid valve incompetence, displacement of the tricuspid valve and dilatation of the atrialized portion of the right ventricle. Atrial fibrillation was detected in the electrocardiogram. She underwent tricuspid valve replacement and right atrial maze procedure. She is released from congestive heart failure and remains in sinus rhythm 48 months after the operation.  相似文献   
59.
Introduction Marked activation of thrombosis is common in patients undergoing total hip arthroplasty, especially during reaming of the femur and after insertion of the femoral prosthesis. This suggests that management designed to minimize deep vein thrombosis and fatal pulmonary embolism after total hip arthroplasty should be focused on the period during insertion of the femoral component. In some previous studies, a low dose of heparin administered intraoperatively was shown to suppress the formation of fibrin. Objective The present study was performed to evaluate the influence of intraoperative heparin administration on the D-dimer level and on the prevention of pulmonary embolism after total hip arthroplasty. Material/methods A total of 22 and 26 consecutive patients respectively underwent total hip arthroplasty with and without intraoperative administration of unfractionated heparin. Postoperatively, all patients wore knee-high elastic stockings and were fitted with calf-to-thigh intermittent pneumatic compression devices. Active ankle flexion and extension exercises were commenced as soon as motor function recovered. None of the 48 patients received prophylactic anticoagulants postoperatively. Results There was a significant difference of the mean D-dimer level on the 1st day between the patients with and without intraoperative administration of heparin (8.9 ± 6.6 vs. 15.7 ± 12.7, P < 0.05). Although there were no patients with symptomatic deep venous thrombosis and pulmonary embolism, asymptomatic pulmonary embolism was detected by pulmonary perfusion scintigraphy in three patients who did not receive intraoperative heparin. The operative blood loss and postoperative drainage were similar in both groups and no bleeding complications were observed. In conclusion, we recommend a safe and inexpensive regimen comprising 1,000 U of intravenous unfractionated heparin intraoperatively, postoperative pneumatic compression, and early active mobilization for prevention of thoromboembolic complications after total hip arthroplasty.  相似文献   
60.
BACKGROUND AND OBJECTIVE: Matrix metalloproteinase-2 (MMP-2) degrades both fibrillar collagens and elastin. MMP-2 is secreted as a latent 72-kd proenzyme that must be proteolytically processed to the 62-kd active form. In our laboratory we demonstrated a significant increase of active, matrix-bound MMP-2 in abdominal aortic aneurysmal (AAA) tissue compared with nonaneurysmal aorta with arteriosclerotic occlusive disease and normal aortic tissue. This increase in active MMP-2 is considered to be important in aneurysm pathogenesis, but the mechanism of its activation in aortic tissue is unknown. Membrane type-1 MMP (MT-1 MMP) is known to be an activator of MMP-2. The purpose of this study was to determine MT-1 MMP expression and its involvement in pro-MMP-2 activation in human aneurysmal tissue. METHODS: Infrarenal aortic tissue was obtained during the surgical repair of AAAs or the bypass of aortoiliac occlusive disease, or from nondiseased aorta, and the expression of MT-1 MMP messenger RNA was determined with Northern blot analysis. MT-1 MMP protein was determined with immunoblot and immunohistochemistry. The ability of aortic tissue to activate pro-MMP-2 was analyzed by incubating aortic tissue with exogenous radiolabeled pro-MMP-2. RESULTS: MT-1 MMP messenger RNA and protein are increased in AAA (P <.05) compared with arteriosclerotic occlusive disease and normal aortic tissue. Immunohistochemical analysis localized MT-1 MMP to aortic smooth muscle cells and macrophages in aneurysmal tissue. AAA tissue demonstrated a greater capacity to activate exogenous pro-MMP-2 compared with atherosclerotic and normal aortic tissue (P <.05). CONCLUSION: These studies demonstrate that MT-1 MMP is increased in AAA tissue and suggest that it may be important in AAA pathogenesis through its ability to activate pro-MMP-2  相似文献   
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