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AIM: The role of air plethysmography (APG) in the diagnosis of chronic venous insufficiency has not been well established. The purpose of this study was to elucidate the relationship between APG parameters and clinical severity in patients with chronic venous insufficiency. METHODS: Two hundred and ninety-four limbs in 154 patients with primary varicose veins were evaluated by APG. Limbs were categorized according to the clinical classification of chronic venous disease suggested by the Ad Hoc Committee on Reporting Standards in Venous Disease of the North American Chapter of the Society for Vascular Surgery and International Society for Cardiovascular Surgery (SVS/ ISCVS). RESULTS: The venous filling index (VFI) was significantly higher in classes 2, 3, 4, and 5+6 than in class 0 or 1, and did not differ among classes 2, 3, 4, 5+6. The ejection fraction did not differ significantly among the 6 classes, and the residual volume fraction was significantly higher in classes 2, 3, 5+6 than in class 0. CONCLUSIONS: APG is a reasonable method for distinguishing the presence or absence of chronic venous insufficiency, but it cannot discriminate the clinical severity. Among APG parameters, the VFI is the most useful diagnostic parameter in the evaluation of chronic venous insufficiency.  相似文献   
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Pulse-height and time spectra of afterpulses from a scintillation detector with NE102A scintillator sandwiching a 60Co source were observed at several different temperatures. From time analysis with a slow amplifier followed by a conventional TAC, spurious pulses are grouped into two types; time-dependent afterpulses and random noise. The intensity of afterpulses decreased considerably with increasing temperature, while the intensity of random noise pulses increased abruptly above 50 degrees C. Experiments, in which the temperatures of scintillator sheets and of the photomultiplier tube were changed separately, suggested that the time-dependent afterpulses were produced in the scintillator itself, while the random component arose from photomultiplier tube.  相似文献   
35.
Prostaglandin E1 (PGE1) has several potential therapeutic effects, including cytoprotection, vasodilation, and inhibition of platelet aggregation. This study investigates the protective action of PGE1 against hepatic ischemia/reperfusion injury in vivo using a complementary DNA microarray. PGE1 or saline was continuously administered intravenously to mice in which the left lobe of the liver was made ischemic for 30 minutes and then reperfused. Livers were harvested 0, 10, and 30 minutes postreperfusion. Messenger RNA was extracted, and the samples were labeled with two different fluorescent dyes and hybridized to the RIKEN set of 18,816 full-length enriched mouse complementary DNA microarrays. Serum alanine aminotransferase and aspartate aminotransferase levels at 180 minutes postreperfusion were significantly lower in the PGE1-treated group than in the saline-treated group. The cDNA microarray analysis revealed that the genes encoding heat-shock protein (HSP) 70, glucose-regulated protein 78, HSP86, and glutathione S-transferase were upregulated at the end of the ischemic period (0 minutes postreperfusion) in the PGE1 group. Our results suggested that PGE1 induces HSPs immediately after ischemia reperfusion. HSPs might therefore play an important role in the protective effects of PGE1 against ischemia/reperfusion injury of the liver.  相似文献   
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Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT.  相似文献   
37.
The goal of endoscopic mucosal resection (EMR) is to allow the endoscopist to obtain tissue or resect lesions not previously amenable to standard biopsy or excisional techniques and to remove malignant lesions without open surgery. In this article, we describe the results of conventional EMR and EMR using an insulation‐tipped (IT) electrosurgical knife (submucosal dissection method) for large colorectal mucosal neoplasms and discuss the problems and future prospects of these procedures. At present, conventional EMR is much more feasible than EMR using IT‐knife from the perspectives of time, money, complication, and organ preservation. However, larger lesions tend to be resected in a piecemeal fashion; and it is difficult to confirm whether EMR has been complete. For accurate histopathological assessment of the resected specimen en bloc EMR is desirable although further experience is needed to establish its safety and efficacy. Further improvements of in EMR with special knife techniques are required to simply and safely remove large colorectal neoplasms.  相似文献   
38.
Subdural hygroma is a frequent delayed complication of head trauma. Most hygromas are clinically 'silent' and a few cases have shown slow deterioration in the chronic stage. We report a case of subdural hygroma showing unique radiological findings and rapid deterioration. A 74-years-old female presented with a mild headache and consciousness disturbance after head injury. Computed tomography showed a midline shift as a result of two components piling up in the subdural space; the outer components showed low density, the inner components high density. Magnetic resonance imaging demonstrated that these two subdural components were subdural hygroma and subarachnoid hematoma. Simple burr hole irrigation, rather than large craniotomy, was thought to be more appropriate treatment to reduce the mass effect. Simple burr hole irrigation was performed to remove the subdural hygroma and the patient showed an excellent recovery. Careful examination of the radiological findings prevented an unnecessary procedure in this case. A possible mechanism of this phenomenon is discussed.  相似文献   
39.
Summary: Purpose: We wished to assess the risk of terato-genicity of zonisamide (ZNS) in humans.
Methods: Pregnant epileptic women treated with ZNS and their offspring were prospectively monitored from June 1989 to December 1994. The outcome of pregnancy and status of neonates were examined based on the same standardized protocol.
Results: Twenty-six offspring exposed to ZNS with or without other antiepileptic drugs (AEDs) were studied. Malformations were detected in 2 offspring (7·7%) exposed to ZNS polypharmacy. Anencephaly was detected in one case at 16 weeks of gestation (case 1, artificial abortion), and atrial septa1 defect was detected in another case at 37 weeks of gestation (case 2, delivery by cesarean section). Serum concentrations of ZNS during the first trimester of pregnancy were 6·1 μg/ml in case 1 and 6·3μ/ml in case 2; in both cases, the levels were below the therapeutic concentration range of ZNS.
Conclusions: Teratogenic effects of ZNS were not clearly defined from these results since malformations were detected in two polypharmacy cases but not in four monopharmacy cases. The present data do not indicate that the risk of ZNS teratogenicity is greater than that of other conventional AEDs. However, such risk cannot be neglected even at therapeutic dosages or concentrations of ZNS, especially in patients receiving polypharmacy.  相似文献   
40.
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