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541.
Mucosa-associated lymphoid tissue (MALT) lymphoma arising in the thymus is extremely rare and little is known regarding its clinicopathological features. This study examined the clinicopathological features of nine cases of thymic MALT lymphoma. Most patients had autoimmune disease or hyperglobulinemia, and they also had cysts in the tumors. Both increased serum autoantibody levels and polyclonal serum immunoglobulin levels remained essentially unchanged after total thymectomy in all patients. Thymic MALT lymphoma needs to be included in the differential diagnosis in Asian patients with a cystic thymic mass accompanied by autoimmune disease or hyperglobulinemia.  相似文献   
542.
Digit-assisted thoracoscopic surgery (DATS) is a novel, minimally invasive approach for achieving a superior mediastinal mass, by allowing the surgeon’s finger to pass into the superior mediastinum through a suprasternal route. In this study a DATS procedure for a bronchogenic cyst in the superior mediastinum was performed. The procedure worked well for dissecting the tissue around the mass, and thus reduced the effort required to perform the operation. In the current study DATS was found to be superior to the standard technique.  相似文献   
543.
In Japan, little is known about using the Cell Saver in treating blunt or penetrating chest trauma. We therefore report the utility of this autologous blood salvage device. Two patients underwent emergency thoracotomies with the Cell Saver to treat massive hemothorax and made full recoveries. The first was a 29-year-old man who suffered a stab injury to his chest; 5000 ml blood was collected from the thorax, of which about 3000 ml was reinfused. The second was a 51-year-old man involved in a car crash; 1600 ml blood was collected from the thorax, of which about 500 ml was reinfused. When no banked blood is available for an emergency thoracotomy, the Cell Saver is an extremely useful machine. This device is also effective in treating progressive hemorrhagic shock and helpful when the rate of blood loss exceeds the supply available from the blood bank.  相似文献   
544.
We herein report an extremely rare case of a patient chylothorax at an interval of 20 years after thoracic vertebrae fractures, who underwent a successful thoracoscopic thoracic duct ligation and pleurodesis. A 51-year-old man was referred to our hospital with shortness of breath on effort about 1 month after participating in archery. Twenty years previously, he was involved in a traffic accident. At that time, the patient sustained trauma to the spine and suffered a spinal injury, thus resulting in paralysis in the lower part of his body. A chest roentgenogram and computed tomogram revealed a large amount of bilateral pleural effusion. After thoracentesis was performed, a diagnosis of chylothorax was made and the patient was hospitalized. Conservative management by a low-fat diet proved to be unsuccessful. The patient did not request pleurodesis, because pleural adhesions might impair pulmonary function. As a result, we decided to perform surgery. On the right side, we performed video-assisted thoracoscopic surgery by clipping the thoracic duct and applying an absorbable sealing material. Thereafter, pleurodesis was performed and OK-432 was instilled. Thereafter, the pleural fluid flow was almost completely stopped. On the left side, pleurodesis was effective. The patient has since remained symptom free and has been followed up on an outpatient basis for 9 months after the 100th postoperative day. We assumed that the chylothorax in this case was related to the earlier traffic accident.  相似文献   
545.
The purpose of this study was to examine the hemodynamic characteristics of expanded polytetrafluoroethylene (ePTFE) pulmonary valves with bulging sinuses quantitatively in a pediatric pulmonary mechanical circulatory system designed by us, in order to propose the optimal design for clinical applications. In this study, we developed a pediatric pulmonary mock circulation system, which consisted of a pneumatic right ventricular model, a pulmonary heart valve chamber, and a pulmonary elastic compliance tubing with resistive units. The hemodynamic characteristics of four different types of ePTFE valves and a monoleaflet mechanical heart valve were examined. Relationships between the leaflet movements and fluid characteristics were evaluated based on engineering analyses using echocardiography and a high-speed video camera under the pediatric circulatory conditions of the mock system. We successfully performed hemodynamic simulations in our pediatric pulmonary circulatory system that could be useful for quantitatively evaluating the pediatric heart valves. In the simulation study, the ePTFE valve with bulging sinuses exhibited a large eddy in the vicinity of the leaflets, whereas the straight tubing exhibited turbulent flow. The Reynolds number obtained in the valve with bulging sinuses was calculated to be 1667, which was smaller than that in the straight tubing (R (e) = 2454).The hemodynamic characteristics of ePTFE pediatric pulmonary heart valves were examined in our mock circulatory system. The presence of the bulging sinuses in the pulmonary heart valve decreased the hydrodynamic energy loss and increased the systolic opening area. Based on an in vitro experiment, we were able to propose an optimal selection of pulmonary valve design parameters that could yield a more sophisticated pediatric ePTFE valve shape.  相似文献   
546.
547.

BACKGROUND:

KRAS and epidermal growth factor receptor (EGFR) mutations are thought to play an important role in the carcinogenesis of lung adenocarcinoma. However, clinicopathological findings of KRAS mutated adenocarcinoma cases have not yet been fully clarified. The authors analyzed the relationship between the KRAS mutation and corresponding clinicopathological findings, focusing on nonmucinous and mucinous bronchioloalveolar elements.

METHODS:

EGFR and KRAS mutations were detected in DNA samples extracted from 182 surgically resected tissues of lung adenocarcinomas by the Smart Amplification Process. The relations between gene mutation status and clinicopathological features were analyzed. All adenocarcinoma cases were divided into bronchioloalveolar carcinoma (BAC), adenocarcinoma with bronchioloalveolar features, and adenocarcinoma without BAC components (non‐BAC). BAC/adenocarcinoma with bronchioloalveolar features tumors were further assessed for the presence of mucinous features.

RESULTS:

EGFR and KRAS mutations were found in 76 and 30 cases, respectively. In the KRAS mutant group, BAC/adenocarcinoma with bronchioloalveolar features was found in 22 cases, which included 10 nonmucinous and 12 mucinous tumors. Of 19 cases with mucinous BAC/adenocarcinoma with bronchioloalveolar features, KRAS mutations were detected in 12, but no EGFR mutation was detected. In the KRAS mutant group, BAC/adenocarcinoma with bronchioloalveolar features had significantly earlier pathological stages and more favorable prognoses than did non‐BAC. Mucinous BAC/adenocarcinoma with bronchioloalveolar features showed less smoking history than did nonmucinous BAC/adenocarcinoma with bronchioloalveolar features and non‐BAC. Furthermore, transversion type KRAS mutations were more common in non‐BAC.

CONCLUSIONS:

KRAS mutated adenocarcinomas can be divided into BAC/adenocarcinoma with bronchioloalveolar features and non‐BAC types. Non‐BAC adenocarcinoma is related to smoking history and has a poor prognosis. BAC/adenocarcinoma with bronchioloalveolar features adenocarcinoma, however, has a more favorable prognosis, and mucinous BAC/adenocarcinoma with bronchioloalveolar features has little relationship to smoking history. Cancer 2011;. © 2011 American Cancer Society.  相似文献   
548.
549.
A 73-year-old woman visited our hospital complaining of general fatigue and jaundice. Laboratory tests revealed an elevated total bilirubin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase and γ-glutamyltransferase. Computed tomography and magnetic resonance imaging demonstrated a mass lesion at the ampulla of Vater with dilatation of the common bile duct and main pancreatic duct. Percutaneous transhepatic cholangiography revealed dilatation of the bile duct and a negative filling defect due to the tumor. Pancreatoduodenectomy was performed. The specimen included an ulcerated firm tumor of the papilla Vater. The surface of the ampulla consisted of well-differentiated papillary adenocarcinoma, whereas the deep layer, such as submucosal or muscular layer, contained large cell neuroendocrine carcinoma and squamous cell carcinoma. Immunohistochemistry revealed that the large cell neuroendocrine carcinoma component was positive for chromogranin A, synaptophysin and CD56. The patient died from multiple liver and bone metastases 13 months after surgery. This is a very rare case of a large cell neuroendocrine carcinoma accompanied by adenocarcinoma and squamous cell carcinoma components.  相似文献   
550.

Background

To evaluate the plasma vascular endothelial growth factor (VEGF) levels after one intravitreal injection of aflibercept or ranibizumab in patients with exudative age-related macular degeneration (AMD).

Methods

Twenty-four Japanese with exudative AMD, polypoidal choroidal vasculopathy, and retinal angiomatous proliferation were included. Fourteen patients received an intravitreal injection of aflibercept, and ten patients received an intravitreal injection of ranibizumab. Plasma VEGF levels were evaluated within 7 days before the intravitreal injections and 1 day, 1 week, and 1 month after the intravitreal injection.

Results

In the ranibizumab group, the mean plasma VEGF levels were 245.7?±?233.4 pg/ml before the injection, 246.6?±?304.8 pg/ml after 1 day, 217.8?±?212.9 pg/ml after 1 week, and 260.0?±?290.1 pg/ml after 1 month. The plasma VEGF levels did not decrease significantly in patients in the ranibizumab group at any time point. In the aflibercept group, the mean plasma VEGF levels were 280.0?±?170.3 pg/ml before the intravitreal injection and 8.2?±?12.9 pg/ml after 1 day, 9.1?±?9.1 pg/ml after 1 week, and 41.9?±?41.4 pg/ml after 1 month (p?Conclusion Intravitreally injected aflibercept reduced plasma VEGF over at least 1 month. In contrast, intravitreal injection of ranibizumab did not cause a significant reduction in the plasma VEGF levels.  相似文献   
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