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91.
We report a case of primary diffuse leptomeningeal gliomatosis (PDLG) followed up with serial magnetic resonance images (MRI). A 45‐year‐old man manifested with bilateral abducens nerve palsy and meningisms. Repeated MRI revealed diffuse leptomeningeal enhancement throughout the central nervous system without intra‐axial mass accompanied with the dilatation of ventricles and focally enlarged cerebral sulci. Brain biopsies showed a leptomeningeal gliomatosis. The MRI findings described here would contribute to the diagnosis of PDLG among other common diseases diffusely spreading along the leptomeningeal structures.  相似文献   
92.
A 57-year-old man with a history of renal cell carcinoma presented with presyncope. He underwent nephrectomy years earlier followed by HLA-matched allogeneic peripheral-blood stem-cell transplantation. Echocardiographic investigation revealed a solitary right ventricle mass without contiguous vena caval or right atrial involvement. The mass was pathologically confirmed to be metastatic carcinoma in the right ventricular cavity. This case highlights the need to consider an underlying neoplastic syndrome in patients presenting isolated right ventricle mass by echocardiography.  相似文献   
93.
94.
We aimed to examine the effects of KTO-7924 (beta3-adrenoceptor agonist) on lipid metabolism and mRNA expressions in retroperitoneal white adipose tissue (RP WAT) in obese (fa/fa) Zucker rats using DNA microarray. Oral KTO-7924 for 28 days significantly decreased RP WAT weight, plasma triglyceride, free fatty acid, and insulin, and improved insulin resistance in oral glucose tolerance tests. In RP WAT of KTO-7924-treated rats, DNA microarray analysis revealed specifically enhanced mRNA expressions of uncoupling protein 1 (UCP1) and cytochrome c oxidase subunit VIII-H (COX8H), which are reportedly highly expressed in brown adipose tissue (BAT). Since these mRNA expression levels in RP WAT were significantly lower in obese (fa/fa) Zucker rats than in lean Zucker rats, these genes may be important in lipid metabolism. Our results imply that in obese (fa/fa) Zucker rats, continuous stimulation of beta3-adrenoceptors by KTO-7924 causes BAT-like adipocytes to appear in RP WAT, and improves lipid metabolism.  相似文献   
95.
Malignant peripheral nerve sheath tumors (MPNSTs; malignant schwannomas) rarely occur in the anterior mediastinum, and their prognosis is poor. A 75-year-old man was referred to our hospital for examination of an anterior mediastinal tumor. A computed tomography-guided percutaneous needle biopsy revealed only fibrosis. The tumor was completely excised via a median sternotomy with partial resection of the pericardium and right upper lobe of the lung. Thereafter, the tumor was diagnosed as a storiform-pleomorphic type of malignant fibrous histiocytoma. At 1 year after the surgery, a distant metastasis was found in the interlobular space between the right middle and lower lobes. The tumor was completely excised via a right posterolateral thoracotomy. Reexamination of the primary and secondary tumors revealed an MPNST. No recurrence was found up to 5 years after the second surgery without adjuvant chemotherapy or radiation therapy. However, he died from multiple lung metastases after 6 years.  相似文献   
96.
PURPOSE: We assessed the feasibility of utilizing three-dimensional (3D) phase sensitive inversion recovery (IR) images for preoperatively determining deep brain stimulator position. METHODS: We measured geometric distortion with a grid phantom and evaluated images of 3 volunteers to determine optimum imaging parameters for 3D phase sensitive IR. RESULTS: Geometric distortion measured less than 1.0%. Respective inversion and recovery times, which provided high T(1) contrast between the subthalamic nucleus and adjacent tissue, were 200 and 4000 ms. In studies of 3 volunteers and 2 patients, the subthalamic nucleus was clearly depicted in 3D phase sensitive IR images. The measured coordinates of the subthalamic nucleus agreed well with those calculated by conventional estimation from midpoint of the anterior and posterior commissure. CONCLUSION: Three-dimensional phase sensitive inversion recovery was useful in visualizing the subthalamic nucleus for effective deep brain stimulation.  相似文献   
97.
We present here a rare case of left-side catamenial pneumothorax, in which endometrial tissue pleura was found on the visceral pleura histologically. A chest roentogenogram confirmed the left pneumothorax, but did not reveal bullae or any associated anomalies, in a 41-year-old woman with three documented episodes of left-side pneumothorax occurring every menstruation. Video-assisted thoracoscopic surgery revealed not only tiny holes in the diaphragm, but also a scattered small brown spots on the visceral pleura. Histological examination of the lung sections revealed the existence of endometrial tissue on the visceral pleura with disrupted pleural elastic fibers. Our case suggests that cyclic erosion of the visceral pleura by the implanted endometrial tissue caused air leakage from the lung, in addition to the most accepted concept that air is aspirated into the thoracic cavity via the abdomen through the acquired fenestration of the diaphragm.  相似文献   
98.
We report a rare case of constrictive pericarditis that stimulated a large mediastinal tumor obstructing the right ventricular inflow tract. A 58-year-old woman was referred to our hospital because of a recent increase of dyspnea and facial edema. Computed tomography revealed severely thickened calcification, including a low-density area, presenting as a mediastinal tumor, compressing the right ventricular inflow tract. A complete resection was performed, and her symptoms dramatically improved. Idiopathic constrictive pericarditis was diagnosed pathologically.  相似文献   
99.
OBJECTIVE: To clarify the position of on-pump beating coronary artery bypass (CAB) and to define preoperative indicators of intentional conversion to the procedure in the era of advancement of off-pump CAB (OPCAB), we assessed on-pump beating CAB performed after the introduction of OPCAB. SUBJECTS AND METHODS: We assessed 130 patients who underwent single CAB [117 (90%) with OPCAB and 13 (10%) with on-pump beating CAB] between August 1999 (when OPCAB was selected as the first-line surgical procedure) and December 2004. RESULTS: No significant differences were seen between the groups in the number of coronary lesions or the prevalence of left main trunk (LMT) lesion. Reduced left cardiac function, cardiac dilatation, and mitral regurgitation (MR) were more remarkable in the on-pump beating CAB group. Preoperative ischemic condition was generally unstable in the both groups. A conversion to on-pump beating CAB occurred at anastomosis for the left anterior descending (LAD) branch in 61% and for the left circumflex (LCX) branch in 15%. LAD patients had more severe left cardiac dysfunction and cardiac dilatation than LCX patients. CONCLUSION: To perform safe and reliable CAB surgery, cardiovascular surgeons should define preoperative indicators of difficult OPCAB and convert OPCAB to on-pump beating CAB intentionally without hesitation when unstable hemodynamics is detected.  相似文献   
100.
Aneurysm of the innominate artery is uncommon compared with other peripheral aneurysms, and holds the potential for rupture, embolization, or thrombosis as well as various complications caused by compression to the adjacent structures. The most effective treatment for this condition is surgical resection, but the earlier reports described high mortality rates. We report the case of an 83-year-old asymptomatic woman with an aneurysm in the innominate artery, which was successfully resected and repaired with the use of modern surgical techniques of hypothermic circulatory arrest and selective cerebral perfusion. Aggressive surgical intervention should be employed despite the fact that a patients is asymptomatic.  相似文献   
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