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991.
Radiographic features in lymphoepithelial cyst of the pancreas   总被引:1,自引:0,他引:1  
Two cases of pancreatic lymphoepithelial cyst are presented. Abdominal ultrasonography and endoscopic ultrasonography demonstrated cysts containing keratinized material, indicative of this diagnosis.  相似文献   
992.

Purpose

To investigate the usefulness of contrast advanced dynamic flow imaging and contrast pulse subtraction imaging in the intranodular hemodynamics of hepatic tumors.

Materials and Methods

Ten patients underwent contrast advanced dynamic flow imaging and contrast pulse subtraction imaging using Levovist®, a microbubble contrast agent. Fourteen hepatic tumor nodules were studied: 9 were hepatocellular carcinoma, 1 metastasis, 1 hemangioma, 1 adenomatous hyperplasia, and 2 metastatic lymph nodes of hepatocellular carcinoma. Real-time scanning of contrast advanced dynamic flow imaging and intermittent interval-delay scanning of contrast pulse subtraction imaging were carried out in the early arterial phase, the late vascular phase, and the postvascular phase. The results obtained from contrast advanced dynamic flow imaging and contrast pulse subtraction imaging were compared with those obtained by precontrast power Doppler imaging and three-phase dynamic CT, respectively.

Results

The rate of detection of intranodular vascularity by contrast advanced dynamic flow imaging (93%) or contrast pulse subtraction imaging (93%) was significantly higher than that of precontrast power Doppler imaging (29%) and was as high as that of dynamic CT. Characteristic intranodular hemodynamics were detected in hepatocellular carcinoma, metastasis, hemangioma, and adenomatous hyperplasia with typical appearance of an intranodular blood vessel image in the early arterial phase, a parenchymal stain image in the late vascular phase, and a perfusion defect image in the post-vascular phase.

Conclusion

Contrast advanced dynamic flow imaging and contrast pulse subtraction imaging clearly show the intranodular hemodynamics in hepatic tumors.  相似文献   
993.
BACKGROUND: Hypertriglyceridemia is associated with decreased HDL-cholesterol (HDL-C) and increased small dense LDL. In addition, small dense LDL is known to be susceptible to oxidation. METHODS: We measured LDL particle size, using gradient gel electrophoresis, and malondialdehyde-modified LDL (MDA-LDL), using an ELISA, and investigated the association between triglyceride (TG) concentrations, LDL size, and MDA-LDL. RESULTS: TG concentrations correlated negatively with the predominant LDL size (r = -0.650) and HDL-C concentration (r = -0.556). The relationship between TG concentration and LDL size, evaluated by measuring MDA-LDL, distinguished subgroups derived from four subfractions of TG concentrations and four distribution ranges of LDL size. These experiments indicated that there is a threshold for oxidation susceptibility at an LDL size of 25.5 nm and a TG concentration of 1500 mg/L. To investigate the relationship between LDL size, MDA-LDL concentration, and other lipids (TGs, HDL-C, apolipoprotein B, and total cholesterol), we evaluated them in control subjects and patients with diabetes mellitus or hypertriglyceridemia. When the size range for normal LDL was postulated to be 25.5 < or = phi (LDL diameter) < 26.5 nm, the MDA-LDL concentration was significantly higher in the subgroups of patients with LDL in the size range 24.5 < or = phi < 25.5 nm compared with patients with normal LDL. This result also suggests that the threshold is at a LDL size of 25.5 nm. CONCLUSION: The threshold for oxidation susceptibility coincided with the point of LDL size separation between the LDL subclass patterns A and B as an atherosclerotic risk.  相似文献   
994.
Ultrastructural study of autoptic cerebral tissue from a patient with hereditary degenerative disease of the nervous system revealed lipofuscin-like bodies and variable sized osmiophilic granular masses in neurons. Autofluorescent granules were also found in neurons. Biochemical study demonstrated a deficiency of diaminobenzidine peroxidase and the accumulation of lipopigment in cerebral tissue.  相似文献   
995.
OBJECTIVE: Toxic free radicals cause dysfunction of respiratory muscles, probably leading to respiratory distress. Exposure to high concentrations of oxygen generates plenty of free radicals. Lidocaine scavenges the reactive molecules. The purposes of the current study were first to examine whether hyperoxia impairs diaphragmatic function, and second, to assess the effects of lidocaine on hyperoxia-induced diaphragmatic dysfunction, if developed. DESIGN: Prospective, randomized animal study. SETTING: University research laboratory. SUBJECTS: Forty and 48 adult male Golden-Syrian hamsters (110-150 g) in parts I and II studies, respectively. INTERVENTION: In the part I study, hyperoxia for 5 and 6 days reduced diaphragmatic contractility and enhanced fatigue. In the part II study, hamsters were randomly allocated to one of six groups (n = 8 each): exposure to air for 6 days with saline (group A-S) or lidocaine infusion (group A-L), exposure to 100% oxygen for 5 days with saline (group 05-S) or lidocaine (group 05-L), and exposure to 100% oxygen for 6 days with saline (group 06-S) or lidocaine (group 06-L). Saline or lidocaine (2 mg/kg/hr) was subcutaneously given immediately before exposure to air or oxygen. Diaphragmatic contractility and fatigability were assessed in vitro using muscle strips excised from the costal diaphragms. Diaphragmatic levels of malondialdehyde (MDA), an index of free radical-mediated lipid peroxidation, were measured. These variables were compared between groups. MEASUREMENTS AND MAIN RESULTS: Twitch and tetanic tensions in groups 05-S and 06-S were reduced compared with group A-S. Tensions generated during fatigue trials were also decreased in groups 05-S and 06-S. MDA levels were elevated in diaphragms from these groups. In groups 05-L and 06-L, contractile dysfunction, deterioration of fatigability, and MDA formation in the diaphragm were attenuated. CONCLUSIONS: Lidocaine attenuated hyperoxia-induced diaphragmatic dysfunction assessed by contractile profiles and fatigability in hamsters. This beneficial effect may be attributable, in part, to inhibition of lipid peroxidation.  相似文献   
996.
Overdosage intoxication of sulindac, tiaramide and diclofenac caused excitability of central nervous system, followed by unconsciousness. The case was treated with ordinary therapies and direct hemoperfusion (DHP). Serum concentrations of these drugs and their metabolites were correlated well with the clinical symptoms. DHP may be effective to eliminate these drugs and their metabolites.  相似文献   
997.
To evaluate the imaging findings of biliary hamartomas (von Meyenburg complexes, vMCs) and discuss their differential diagnosis from other related diseases, imaging findings of biliary hamartomas on ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI), magnetic resonance cholangiopancreatography (MRCP), and hepatobiliary scintigraphy were prospectively analyzed in six patients. On ultrasound images, five of the six cases showed multiple small hyper- and hypoechoic lesions with comet-tail echoes, especially when magnified using the zoom function. In all six cases, multiple tiny hypodense lesions less than 10 mm in diameter were scattered throughout the liver with no enhancement on CT. These tiny lesions were demonstrated to be hyper- and hypointense on T2- and TI-weighted images, respectively, in three patients who underwent MRI examinations. MRCP was performed in two patients, and it clearly showed multiple tiny round and irregular-shaped hyperintense lesions. MRCP and hepatobiliary scintigraphy showed normal appearances of intra- and extrahepatic bile ducts in two and one patients, respectively. Imaging modalities are useful in the diagnosis and differential diagnosis of vMCs. A correct diagnosis might be obtained when typical imaging findings present even without histological confirmation.  相似文献   
998.
OBJECTIVE: The present study was undertaken to evaluate roles of nitric oxide in the central nervous system in the development of neurogenic pulmonary edema. Nitric oxide donor compounds have been reported to be effective for controlling some kinds of pulmonary edema. DESIGN: Randomized trial. SETTING: Experimental university pharmacology laboratory. SUBJECTS: Wistar rats anesthetized with pentobarbital. INTERVENTIONS: Neurogenic pulmonary edema was induced by injections of fibrinogen and thrombin into the cisterna magna. Physiologic roles of nitric oxide were evaluated by using NG-nitro-l-arginine methyl ester (a nitric oxide synthase inhibitor) or l-arginine (a nitric oxide donor compound). Vagus nerves were either left intact or bilaterally severed 20 mins before the injections of fibrinogen and thrombin. MEASUREMENTS AND MAIN RESULTS: Because enhanced sympathetic nerve activity mediates neurogenic pulmonary edema, the concentration of neuropeptide Y, a neurotransmitter, in edema fluid was measured by using enzyme-linked immunosorbent assay. To evaluate the severity of pulmonary edema and pulmonary vascular permeability, lung water content and protein concentration in edema fluid were analyzed. In rats with intact vagus nerves, injection of NG-nitro-l-arginine methyl ester into the cisterna magna worsened the pulmonary edema, whereas l-arginine had no effect. In contrast, in vagotomized rats, l-arginine abrogated pulmonary edema, whereas NG-nitro-l-arginine methyl ester exerted no influence. Likewise, the ratio of edema fluid protein to serum protein and the neuropeptide Y concentration were increased by NG-nitro-l-arginine methyl ester in rats with the vagus nerves intact and were diminished by l-arginine in vagotomized rats. CONCLUSIONS: Neurogenic pulmonary edema is characterized by elevated pulmonary vascular permeability and may be inhibited by nitric oxide production in the medulla oblongata.  相似文献   
999.
1000.
Determine the effectiveness of decontamination, and perform thorough dry or wet decontamination, depending on the circumstances. Always remain cognizant of the fact that, even after decontamination has been completed, contamination may not have been completely eliminated. Perform periodic monitoring to determine whether secondary exposure has occurred in health care workers; if it appears that secondary exposure has occurred, then the PPE level must be increased and attempts must be made to identify and eliminate the source of the contamination. Finally, if the victims were exposed through ingestion, then consider the possibility that secondary exposure will occur during gastric lavage.  相似文献   
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