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81.
Membrane glycoprotein plasma cell 1 (PC-1) has been shown to be increased in type 2 diabetes and involved in insulin resistance through inhibiting the insulin receptor tyrosine kinase, which was demonstrated using cultured breast cancer cells. However, other reports have shown contradictory results in Chinese hamster ovary cells and in vitro kinase assay. Thus, we considered it necessary to investigate the effect of PC-1 using highly insulin-sensitive cells. Here, we used two of the following approaches: 1) investigating PC-1 expression levels in insulin-responsive tissues in rat models of diabetes and 2) overexpressing PC-1 in 3T3-L1 adipocytes. We found that PC-1 was highly expressed in insulin-responsive tissues, such as liver and adipose tissue, in normal rats. However, high-fat feeding or streptozotocin-induced diabetes did not change its expression levels in liver, adipose tissue, and skeletal muscle. Thus, PC-1 expression levels were not associated with high-fat-diet-induced insulin resistance or hyperglycemia. Although PC-1 was increased in adipose tissue in Zucker fatty rats (protein level, by 50%; mRNA level, by 90%), its expression levels in liver and skeletal muscle, tissues that are more responsible for whole body glucose metabolism than adipose tissue, did not significantly differ from those in normal rats. Next, we overexpressed PC-1 in 3T3-L1 adipocytes using an adenovirus transfection system. PC-1 expression was markedly increased to a level 16-fold greater than that in normal human adipose tissue, which is higher than the previously reported levels in diabetic patients. However, insulin-induced tyrosine phosphorylation of the insulin receptor and insulin receptor substrate 1, activation of phosphatidylinositol 3-kinase, and glucose uptake were not affected by PC-1 overexpression. These results strongly suggest that increased PC-1 expression is not causally related to insulin resistance.  相似文献   
82.

Purpose

To evaluate the feasibility of aspirin continuation during the perioperative period for pulmonary resection in lung cancer patients.

Methods

A retrospective study was conducted in 46 patients who were taking aspirin and underwent pulmonary resection. The indications for aspirin were generally a cardiovascular or cerebrovascular comorbidity. Whether to continue or discontinue aspirin was determined based on the severity of the cardiovascular or cerebrovascular comorbidity, along with the patient’s overall condition. The intraoperative and postoperative outcomes were compared between patients continuing and those discontinuing aspirin.

Results

Twenty patients continued (group C) and 26 patients discontinued (group D) aspirin. The length of the operation (226 ± 97 min in group C vs. 189 ± 90 min in group D), intraoperative bleeding (234 ± 232 vs. 204 ± 367 g) and average pleural discharge on postoperative days 1, 2 and 3 (331, 230 and 215 vs. 304, 210 and 174 ml/day) showed no significant differences between the two groups. The postoperative complication rates were also not significantly different between the two groups [eight patients (40 %) in group C vs. nine patients (35 %) in group D].

Conclusions

Continuous administration of aspirin during the perioperative period for pulmonary resection in lung cancer patients appears to be clinically feasible in the Japanese population.  相似文献   
83.
We report an unusual case of synchronous triple early cancers of the stomach, gallbladder and sigmoid colon. The patient was a 70-year-old man. Gastrointestinal endoscopy at a medical check-up initially revealed early gastric cancer. A thorough preoperative investigation showed a gallbladder tumour and early colon cancer. Endoscopic mucosal resection was performed for the colon cancer. Microscopically, the specimen showed well-differentiated adenocarcinoma involving the submucosal layer. Distal partial gastrectomy (D1) and simple cholecystectomy with lymph node dissection were also performed. The histopathological diagnosis was well-differentiated adenocarcinoma in the stomach (T1, N0, M0; Stage IA) and poorly differentiated papillary adenocarcinoma (T1, N0, M0; Stage I) in the gallbladder. The patient was doing well with no evidence of recurrence 6 months after surgery.  相似文献   
84.
OBJECTIVE: We conducted a retrospective study to evaluate two different types of percutaneous fluoroscopic gastrostomy procedures and catheters. MATERIALS AND METHODS: Between July 8, 1999, and August 4, 2000, 80 percutaneous gastrostomy catheters were placed in 80 patients in 80 attempts. Twenty-five 16-, 18-, or 20-French balloon-retained catheters and 55 20-French mushroom-retained catheters were inserted. Typically, the type of catheters placed was based on operator preference. However, balloon-retained tubes were preferred for use in patients with obstructive head and neck or esophageal malignancies, and mushroom-retained catheters were preferred for use in demented or combative patients. Follow-up was conducted through chart reviews and telephone interviews. The technical success, procedural complications, and catheter complications were recorded. Chi-square statistical analysis was performed. RESULTS: Technical success was 100% (80/80 patients), and no procedural complications occurred. In patients who received balloon-retained catheters, the major complication rate was 0%, the minor complication rate was 8% (2/25 patients), and the tube complication rate was 68% (17/25 patients). The following complications occurred: catheter dislodgment (n = 17), superficial cellulitis (n = 1), and bleeding gastric ulcer (n = 1). In patients who received mushroom-retained catheters, the major complication rate was 0%, the minor complication rate was 3.6% (2/55 patients), and the tube complication rate was 3.6% (2/55 patients). The following complications occurred: superficial cellulitis (n = 2), tube occlusion (n = 1), and peristomal tube leakage (n = 1). No significant differences in major or minor complications were found between the gastrostomy procedures. Balloon-retained catheters had a significantly higher rate of tube complications (p < 0.001). CONCLUSION: Compared with balloon-retained catheters, mushroom-retained gastrostomy catheters are significantly more durable, more secure, and less prone to tube dysfunction. Mushroom-retained catheters should be the preferred type of gastrostomy catheter to place in patients whenever possible.  相似文献   
85.
86.
PURPOSE: To evaluate the long-term effectiveness of the percutaneous treatment of portal venous stenoses in children and adolescents with reduced-size hepatic transplants. MATERIALS AND METHODS: During the past 5 years, percutaneous transhepatic balloon venoplasty was attempted in 25 children and adolescents with anastomotic portal venous stenoses that occurred after reduced-size hepatic transplantation. All procedures were performed with direct puncture of the intrahepatic portal vein and with subsequent balloon dilation. Intravascular stents were deployed in patients with suboptimal results after dilation or with recurrent stenoses. RESULTS: Percutaneous venoplasty was technically successful in 19 of 25 patients. In the remaining six patients, portal venous occlusion precluded access to the extrahepatic portal vein. Intravascular stents were deployed in 12 patients for "elastic" (n = 5) or recurrent (n = 7) stenoses. Seven patients who underwent successful venoplasty without stent placement have required no further intervention. All stents have remained patent without further intervention. Portal venous patency has been maintained for 5-61 months (mean time, 46 months) in all 19 patients. CONCLUSION: Percutaneous treatment of portal venous stenoses is effective and long lasting in children with reduced-size hepatic transplants. In patients with elastic or recurrent lesions, portal venous stents have excellent long-term primary patency despite continued patient growth. Successful, percutaneous transhepatic venoplasty eliminates the need for surgical revision, portacaval shunting, or repeat transplantation.  相似文献   
87.
PurposeTo determine whether there is a cost advantage for one of the three commonly performed interventional radiology (IR) procedures (chemoembolization, selective internal radiation therapy [SIRT], radiofrequency ablation [RFA]) in the treatment of hepatocellular carcinoma (HCC).Materials and MethodsA cost analysis from the payer perspective was performed. Primary data were collected from a university hospital, and sensitivity testing was done by comparing coding information obtained at two other tertiary care medical facilities. Medicare allowable reimbursements were used to estimate costs. Decision analytic models using decision tree analysis and Monte Carlo simulations were used to compare alternatives. Simulations were performed comparing all three procedures, followed by a two-way comparison of chemoembolization and SIRT.ResultsSimple decision tree analyses showed that RFA was less expensive compared with chemoembolization and SIRT. Monte Carlo simulations showed average reimbursements for each of the three procedures that was largely dependent on the number of repeat procedures required ($9,362 vs $30,107 vs $35,629 for RFA, chemoembolization, and SIRT; P < .001). When comparing only chemoembolization and SIRT, chemoembolization was the lower cost strategy in most scenarios, but SIRT was lower in cost in more than one-third of the simulations.ConclusionsRFA was the least costly of the three IR strategies in nearly all scenarios studied in these models. Although chemoembolization was less expensive than SIRT in most instances, Monte Carlo simulation showed a preference for SIRT in more than one-third of all scenarios. Sensitivity analyses showed that the most important variables assessed were the need for repeat procedures.  相似文献   
88.
The Günther Tulip vena cava filter is designed for removal by the internal jugular vein approach with use of a blunted hook placed at the superior aspect of the filter. Removal of this filter was performed by the femoral approach in a patient with central venous occlusion that precluded removal by the conventional approach.  相似文献   
89.
Background: Although donepezil, an acetylcholinesterase inhibitor, has been proved to be effective in ameliorating cognitive impairment in Parkinson's disease with dementia (PDD), the responsiveness of patients to donepezil therapy varies. [5-(11)C-methoxy]donepezil, the radiolabeled form of donepezil, is a ligand for positron emission tomography (PET), which can be exploited for the quantitative analysis of donepezil binding to acetylcholinesterase and for cholinergic imaging. Objectives: To investigate the deficits of the cholinergic system in the brain in PDD and its association with response to donepezil therapy. Methods: Twelve patients with PDD and 13 normal control subjects underwent [5-(11)C-methoxy]donepezil-PET imaging. For patients with PDD, daily administration of donepezil was started after [5-(11)C-methoxy]donepezil-PET imaging and continued for 3 months. Results: In the PDD group, the mean total distribution volume of the cerebral cortices was 22.7% lower than that of the normal control group. The mean total distribution volume of the patients with PDD was significantly correlated with improvement of visuoperceptual function after 3 months of donepezil therapy. Conclusion: The results suggest that donepezil therapy is more effective in patients with less decrease in acetylcholinesterase, a binding site of donepezil, at least in the specific cognitive domain.  相似文献   
90.
The aim of this study is to demonstrate and review the detailed microsurgical anatomy of the abducens nerve and surrounding structures along its entire course and to provide its topographic measurements. Ten cadaveric heads were examined using ×3 to ×40 magnification after the arteries and veins were injected with colored silicone. Both sides of each cadaveric head were dissected using different skull base approaches to demonstrate the entire course of the abducens nerve from the pontomedullary sulcus to the lateral rectus muscle. The anatomy of the petroclival area and the cavernous sinus through which the abducens nerve passes are complex due to the high density of critically important neural and vascular structures. The abducens nerve has angulations and fixation points along its course that put the nerve at risk in many clinical situations. From a surgical viewpoint, the petrous tubercle of the petrous apex is an intraoperative landmark to avoid damage to the abducens nerve. The abducens nerve is quite different from the other nerves. No other cranial nerve has a long intradural path with angulations and fixations such as the abducens nerve in petroclival venous confluence. A precise knowledge of the relationship between the abducens nerve and surrounding structures has allowed neurosurgeon to approach the clivus, petroclival area, cavernous sinus, and superior orbital fissure without surgical complications. Clin. Anat. 25:1030–1042, 2012. © 2012 Wiley Periodicals, Inc.  相似文献   
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