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91.
BACKGROUND AND PURPOSE: Three-dimensional time-of-flight MR angiography (3D TOF MRA) often discloses prominent posterior cerebral artery (PCA) laterality in the setting of M1-segment middle cerebral artery (MCA) occlusion. We sought to analyze the implications of prominent PCA laterality at 3D TOF MRA. METHODS: We retrospectively reviewed 3D TOF MRA and digital subtraction angiography (DSA) findings in 25 patients (12 male, 13 female; mean age, 68.8 years [age range, 29-94 years]) with M1-segment occlusion. The observable laterality of the PCA, determined on the basis of 3D TOF MRA findings, was scored according to distal signal extent and compared with findings of collateral flow from the ipsilateral PCA via the leptomeningeal anastomosis (LMA) at DSA. Frequency of PCA laterality at 3D TOF MRA in patients and that in 56 healthy control subjects was also compared. RESULTS: The positive predictive value of PCA laterality for the existence of collateral flow was 99.9% and the negative predictive value 30.7%. The distal extent of ipsilateral PCA signal at 3D TOF MRA positively correlated with the grade of collateral flow from the PCA via the LMA (r = 0.802; P <.01). PCA laterality was significantly less common in control subjects (P <.01). CONCLUSION: Prominent PCA laterality at 3D TOF MRA in patients with M1-segment occlusion represents the existence of collateral flow from the PCA via the LMA.  相似文献   
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Three Japanese families with moya-moya disease in six patients are presented. These six patients were among 49 cases of confirmed moya-moya disease in our experience, and the familial incidence was more than 12%. A relatively high familial incidence (7%) was found in the total Japanese series emphasising the important hereditary components in the pathogenesis of the disease.  相似文献   
94.
Hepatoid carcinoma of the ovary is an ovarian carcinoma that has phenotypic properties in common with hepatocellular carcinomas. However, the extent of the tumor cells' similarity to and their difference from hepatocytes is largely unknown. In addition, the precursor cell of origin for hepatoid carcinoma of the ovary has not been identified. Three cases of alpha-fetoprotein-producing hepatoid carcinoma of the ovary that were admixed with an adenocarcinoma of common surface epithelial type are reported. The hepatoid carcinomas had a trabecular architecture with canaliculi detected by polyclonal (but not monoclonal) anticarcinoembryonic antigen antibodies. A hepatic phenotype in the hepatoid tumor cells was further supported by the production of albumin mRNA by in situ hybridization. The adenocarcinomas in the three cases were mucinous (Case 1), serous (Case 2), and endometrioid (Case 3), respectively. The cytokeratin (CK) profile in both the hepatoid and adenocarcinomatous components was CK18+/CK19+/CK20+/-, whereas normal and neoplastic hepatocytes were CK18+/CK19-/CK20-. Although this study supports a hepatic phenotype in ovarian hepatoid carcinoma, the CK profile of hepatoid carcinoma differs from that of normal and neoplastic hepatocytes but resembles that of the associated common epithelial adenocarcinoma. These findings suggest that hepatoid carcinoma of the ovary is probably derived from carcinomas of surface epithelial origin by a process of neometaplasia or transdifferentiation.  相似文献   
95.
Arteriovenous dialysis access may impose a burden on the cardiac system. The objective of this study is to examine the usefulness of access closure in hemodialysis patients with refractory heart failure and to identify possible factors associated with symptomatic improvements. The study population comprised 33 hemodialysis patients with symptomatic heart failure (New York Heart Association [NYHA] class ≥ II), who underwent arteriovenous access closure (30 fistulas and three grafts) between 1991 and 2008. In all patients, heart failure was refractory to all possible medical and surgical treatments, and persisted after optimal dry weight control. First, short-term changes in hemodynamics, clinical symptoms and echocardiographic morphology were examined. Second, clinical and echocardiographic parameters were compared between responders (N=23), who demonstrated NYHA class improvement after access closure, and non-responders (N=10). After access closure, systolic blood pressure rose and the heart rate decreased significantly. Body weight and echocardiographic parameters did not change significantly. Twenty-three patients (70%) demonstrated NYHA class improvement and were designated as responders. In responders, the duration from access creation to closure was significantly shorter and fewer had ischemic heart disease, compared with non-responders. Access flow, cardiac output and ejection fraction were comparable between the two groups. Although the five-year survival was 20.2% in all patients, responders showed better early survival than non-responders. Arteriovenous access closure improved clinical symptoms in 70% of patients with refractory heart failure. This improvement was especially likely to be achieved in patients without ischemic heart disease and those who developed heart failure within a relatively short time after access creation.  相似文献   
96.
Objectives: Chromogranin A (CgA) and neuro‐specific enolase (NSE) are gaining acceptance as markers of several types of neuroendocrine tumors and the concentration of CgA and NSE have been reported to be elevated in relation to neuroendocrine differentiation of prostate cancer. The aim of the present study was to examine the correlation between the immunohistochemical (IHC) findings and serum value for CgA and NSE in untreated stage D2 prostate cancer patients. Methods: Immunohistochemistry was carried out using antibodies against CgA and NSE in 58 patients and, pretreatment serum CgA and NSE levels were measured by monoclonal immunoradiometric assay in 18 patients with stage D2 prostate cancer treated by androgen ablation. We examined the relationship of the pretreatment serum level to IHC findings for CgA and NSE in prostate cancer patients to clinicopathological parameters, and prognosis. Also, we evaluated the correlation of IHC findings to serum levels for CgA and NSE. Results: There was a statistically significant correlation between CgA positivity and serum CgA level (P = 0.0421). However, there was no statistically significant correlation between NSE positivity and serum NSE level (P > 0.05). We divided stage D2 patients into three groups according to IHC positivity of CgA and NSE. The cause‐specific survival was significantly poorer in patients with strongly positive (++) patients for independent CgA and combined CgA with NSE (P = 0.0379). Multivariate analysis of cause‐specific survivals in patients with stage D2 prostate cancer demonstrated that strong IHC stain was considered as independent variable associated with greater risk of death (P = 0.0142). Conclusion: Neuroendocrine differentiation in stage D2 prostate cancer has attracted considerable attention as a potentially findings prognosis. Thus, CgA had a stronger relationship between serum levels and IHC positivity in contrast to NSE, suggesting clinical usefulness as a tumor marker in predicting the extent of neuroendocrine differentiation in prostate cancer.  相似文献   
97.

Introduction  

Mechanical ventilation (MV) can provoke oxidative stress and an inflammatory response, and subsequently cause ventilator-induced lung injury (VILI), a major cause of mortality and morbidity of patients in the intensive care unit. Inhaled hydrogen can act as an antioxidant and may be useful as a novel therapeutic gas. We hypothesized that, owing to its antioxidant and anti-inflammatory properties, inhaled hydrogen therapy could ameliorate VILI.  相似文献   
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Primary lymphoma of the liver is an extremely rare entity; only eight cases have been reported in the literature. We treated a 34-year-old man with primary hepatic lymphoma by right hepatic lobectomy, including right hemicolectomy and nephrectomy. The histological diagnosis was a small cell diffuse histiocytic lymphoma. Details of this case plus that of others in the literature are described in this report.  相似文献   
100.
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