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991.
BACKGROUND: When pharmacotherapy for epilepsy fails, surgical options, although efficacious, are highly invasive. We explored whether ablation of the cerebral cortex can be performed utilizing the cerebral venous system. METHODS: Mapping and radiofrequency ablation was performed via the venous system in two pigs. RESULTS: Eight targeted sites were successfully accessed and four targeted sites successfully ablated via the central cerebral venous network. CONCLUSION: Electrophysiological mapping and radiofrequency ablation of the cerebral cortex can be performed via the cerebral veins.  相似文献   
992.
993.
Background  Postoperative mortality after hepatectomy remains high compared with other types of surgery in patients who have cirrhosis or chronic hepatitis. Although there are several useful perioperative markers of liver dysfunction, there are no standard markers for predicting postoperative liver failure. This study investigated risk factors for postoperative liver failure after resection of hepatocellular carcinoma to detect markers that could identify candidates for hepatectomy. Methods  Perioperative risk factors for liver failure after hepatectomy were analyzed in 191 patients with hepatocellular carcinoma. Multivariate logistic regression analysis was done to investigate factors with a significant independent influence among 35 variables. The ratio of serum hyaluronic acid to the maximum removal rate of technetium-99 m diethylenetriaminepentaacetic acid galactosyl human serum albumin (hyaluronate/GSA-Rmax ratio) was calculated. Results  Liver failure occurred postoperatively in 16 patients, 3 of whom died. The hyaluronate/GSA-Rmax ratio was a risk factor for postoperative liver failure by univariate analysis and was the only risk factor according to multivariate analysis. All three patients who died had a hyaluronic acid/GSA-Rmax ratio ≥ 500 mg min/dl. This ratio had a sensitivity of 88% and a specificity of 92% for predicting liver failure. Conclusions  To reduce postoperative liver failure, preoperative planning should employ various measures of the hepatic functional reserve, including tests of both parenchymal and nonparenchymal liver function. The hyaluronate/GSA-Rmax ratio can predict liver failure after hepatectomy, and a ratio ≥ 500 mg min/dl is a relative contraindication to liver resection.  相似文献   
994.
Free radicals are known to activate coagulation and inhibit fibrinolysis. Edaravone, a free radical scavenger, protects vascular endothelial cells and neurons during acute brain ischemia in in vitro models. Hemorrhagic transformation and treatment outcomes were retrospectively examined in 76 patients with acute cardiogenic embolism treated with edaravone in addition to routine treatment within 24 hours of the onset of symptoms. Hemorrhagic transformation was categorized according to European Cooperative Acute Stroke Study-II. Patient characteristics were also evaluated, including evidence of hypertension, diabetes mellitus, hyperlipidemia, coronary heart disease, history of smoking, National Institutes of Health Stroke Scale on arrival, and modified Rankin scale at 3 months post-onset. Edaravone administration was one of the factors that contributed to increased frequency of hemorrhagic transformation, but had showed no significant relationship with the outcome. The present study showed that edaravone administration increased the frequency of hemorrhagic transformation with heparin in patients with cardiogenic embolism. Free radical scavenging may have promoted the coagulating conditions. Edaravone administration may allow reduction of the dose of heparin and tissue plasminogen activator in patients with acute ischemic stroke.  相似文献   
995.
A 43-year-old woman suffered clinical brain death after severe head injury. The patient met the criteria for the diagnosis of clinical brain death on Day 3. Aggressive hemodynamic and respiratory managements coupled with triple hormone therapy were performed at the family's request, resulting in continued cardiac activity for a prolonged period. Spinal reflexes and automatisms were observed until cardiac arrest. Ventilatory support was discontinued on Day 168, when cardiac death was confirmed, and her kidneys and eyeballs were removed for transplantation. The patient survived for 165 days after the diagnosis of clinical brain death, which is an extremely prolonged period of somatic support for an adult patient after brain death. An extensive and informed discussion on the end-of-life treatment of clinically brain-dead patients is urgently required in Japan to establish treatment guidelines for such patients.  相似文献   
996.
An 85-year-old female presented with a 3-month history of worsening hyperlacrimation and blurred vision following blunt head injury. Her past medical history was unremarkable. Her blood examination identified no abnormal findings. Neuroophthalmological inspection revealed extraocular movement disorder and mild exophthalmos on the affected side. Her visual acuity was not disturbed. Neuroimaging showed a cystic mass located extraconally in the superolateral compartment of the anterior orbit, without enhancement by contrast medium. Surgical exploration resulted in escape of chocolate-colored, liquefied hematoma during dissection. No vascular lesion was found. A grayish-white cyst wall was found adhering strongly to the lateral and superior rectus muscles. The lacrimal gland was not identified. The mass was totally resected. Histological examination indicated dermoid cyst with inflammatory interstitial hemorrhage. No component of vascular malformation or atypia was found. Hyperlacrimation and extraocular movement improved postoperatively. We thought that the previous blunt head injury might have induced intratumoral hemorrhage in the preexisting dermoid cyst and that the escaped contents caused inflammatory irritation, resulting in the hyperlacrimation. Dermoid cyst may show atypical presentation with intratumoral hemorrhage and should always be included in the differential diagnosis of orbital tumor.  相似文献   
997.
An abnormal shadow was detected on chest X-ray mass screening in an asymptomatic 63-year-old man. The further examinations revealed the shadow to be primary lung cancer (Rt. S6. adenocarcinoma, cT2N0M0, c-stage IB) with right aortic arch. We used 3 dimentional-computed tomography (3D-CT) to assess an anatomical feature of vessels in detail. The right lower lobectomy and the dissection of medi astinal lymph nodes was performed. We confirmed no abnormal anatomy of pulmonary artery and vein at surgery, and it was possible to perform right lower lobectomy with the common procedure. Since lymph node was found by intraopetrative pathological examination, since no metastasis from interlobar to subcarinal lymph node was found, we did not perform dissection of upper mediastinal dissection, which was equivalent to ND2a lymph nodes dissection of the left lung cancer in General Rule for Clinical and Pathological Record of Lung Cancer. The patient with right aortic arch is known to have variant anatomy of other intrathoracic vessels occasionally. 3D-CT was quite useful in assessing anatomical feature, and enabled us to perform safe operation.  相似文献   
998.
Bicuspid aortic valve (BAV) is a common congenital heart disease, and it is well known to be a risk factor for ascending aortic dilatation and dissection. We here report a case of 34-year-old woman who underwent Ross procedure with ascending aortic replacement under the diagnosis of subaortic stenosis and ascending aortic aneurysm. She was pointed out to have heart murmur soon after the birth diagnosed as patent ductus arteriosus. The ductus was ligated when she was 3-years-old, however, heart murmur remained. Further examinations revealed that she also had aortic stenosis with BAV. During her 20-year-follow-up, subaortic stenosis and ascending aorta ectasia were also progressed. Pathological examinations of resected ascending aortic wall showed mucoid degeneration and laceration of collagen fibers, suggesting the fragility of dilated aortic wall with BAV.  相似文献   
999.
1000.
Nitrogen-containing bisphosphonates (NBPs) are powerful anti-bone-resorptive drugs, but they frequently induce various inflammatory side effects. Recent clinical applications have disclosed an unexpected new side effect, jaw-bone necrosis and exposure. In vitro studies suggest that the inflammatory effects of NBPs are due to Vgamma2Vdelta2 T-cells, stimulated directly and/or indirectly [the latter via isopentenylpyrophosphate (IPP) in the mevalonate pathway]. Rats and mice, however, lack Vgamma2Vdelta2 T-cells, yet NBPs still induce necrotic and inflammatory reactions. In mice, NBPs induce IL-1-dependent inflammatory reactions, such as inductions of histidine decarboxylase (HDC, the histamine-forming enzyme) in the liver, lung, spleen, and bone marrow, an increase in granulocytic cells in the peritoneal cavity, pleural exudation, and splenomegaly. Here, we examined the involvement of IPP, TNF, macrophages, and T-cells in the inflammatory actions of alendronate (a typical NBP) in mice. Various statins (mevalonate-synthesis inhibitors) suppressed the alendronate-induced HDC inductions, while mevalonate itself augmented such inductions. IPP injection also induced HDC. Like IL-1-deficient mice, TNF-deficient mice were resistant to alendronate-stimulated HDC induction. Alendronate-stimulated HDC inductions were significantly weaker in macrophage-depleted mice and in nude mice than in control mice. Similar, though generally less clear-cut, results were obtained when other alendronate-induced inflammatory reactions were examined. These results suggest that (i) inhibition of the mevalonate pathway causes and/or modifies at least some inflammatory actions of alendronate in mice, (ii) in addition to IL-1, TNF is also involved in the inflammatory actions of alendronate, and (iii) alendronate may act on a variety of cells, including macrophages and T-cells.  相似文献   
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