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21.
Referenceless, or self-reference, thermometry is a technique for mapping temperature differences in the region of interest (ROI) using the baseline phase estimated by extrapolating the field in the surrounding region for estimation (RFE) and subtracting the estimated baseline from the measured field. In the present work a self-reference technique based on complex field estimation using 2D polynomials comprising complex-valued coefficients was proposed and optimized. Numerical simulations with a Gaussian-profiled phase distribution demonstrated that the ROI radius had to be 2.3-2.5 times the standard deviation (SD) of the Gaussian function in order to keep the error below 8% of the peak phase change. The area ratio between the ROI and the RFE had to be larger than 2.0 to maintain the error level. Based on the simulations, and phantom and volunteer experiments, the complex-based method with independently optimized polynomial orders for the two spatial dimensions was compared with the phase-based method using the similar-order optimization strategy. The complex-based method appeared to be useful when phase unwrapping was not removed. Otherwise, the phase-based method yielded equivalent results with less polynomial orders.  相似文献   
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23.
BACKGROUND: We are developing an immunotherapeutic peptide, Cry-consensus peptide, for Japanese cedar pollinosis. Cry-consensus peptide is a recombinant polypeptide containing six major human T-cell epitopes derived from both Cry j 1 and Cry j 2, two major allergens of Japanese cedar pollen. We examined the effect of Cry-consensus peptide on an allergic rhinitis model in B10.S mice, which have one common T-cell epitope in the Cry-consensus peptide. METHODS: B10.S mice were sensitized with Cry j 1/alum, then the Cry-consensus peptide was administered subcutaneously once a week for 5 weeks from the last sensitization. Histamine was dropped in both nostrils (10 microL per nostril) of each mouse on the day before continuous intranasal instillation of Cry j 1. Soon after the final challenge with Cry j 1, the mice were observed for 5 minutes for the resulting number of sneezes. In addition, serum levels of Cry j 1-specific IgE and IgG2a antibody, eosinophil infiltration in nasal tissue, and Cry j 1-specific cytokine production from splenocytes were evaluated. RESULTS: Cry-consensus peptide markedly inhibited Cry j 1-induced sneezes, eosinophil infiltration, and eosinophil peroxidase (EPO) activity in nasal tissue. Cry-consensus peptide inhibited the production of anti-Cry j 1 IgE (Th2-mediated) and significantly enhanced anti-Cry j 1 IgG2a (Th1-mediated). In cytokine production from splenocytes, Cry-consensus peptide significantly decreased in IL-4/IFN-gamma and IL-5/IFN-gamma ratios. CONCLUSIONS: It was concluded that Cry-consensus peptide effectively controlled allergic responses, which results from shifting from a Th2-dominated to a Th1-dominated immune response.  相似文献   
24.
OBJECTIVES: For the histological diagnosis of small lung cancers of 10 mm or less in diameter (< or =10), resection by video-assisted thoracic surgery (VATS) with computed tomography (CT)-guided marking is feasible. One problem is that a small number of these pulmonary nodules are malignant. We retrospectively analyzed CT images of pulmonary nodules to find better criteria to select candidates for resection among patients with small pulmonary nodules. METHODS: Ninety-four patients with indeterminate peripheral pulmonary nodules underwent wedge resection by VATS. High-resolution CT using a 1.25 mm slice included the area of lesions. Nodules were classified by size (< or =10, 11 to 20, >20 mm) and whether they had a ground-glass opacity (GGO) component. RESULTS: The histology of all 94 nodules showed 52 primary lung cancers, 6 metastatic tumors, 5 benign tumors, 8 intrapulmonary lymph nodes, and 23 inflammatory nodules. Ninety-three percent of nodules larger than 20 mm, 75% of nodules 10 to 20 mm, and 43% of nodules < or =10 mm were malignant. Introducing a classification according to GGO component to nodules, malignancy was detected in 88% of nodules with a GGO component and in 30% of nodules without a GGO component among nodules < or =10 mm. Nodules < or =10 mm with a GGO component showed a statistically significant (p < 0.01) correlation with malignancy. CONCLUSIONS: Pulmonary nodules < or =10 mm with GGO should be considered to have a high possibility of malignancy and to be candidates for resection by VATS.  相似文献   
25.
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   
26.
Renal responses to magnesium lithospermate B   总被引:5,自引:0,他引:5  
Renal responses to magnesium lithospermate B isolated from Salviae miltiorrhizae radix were examined in normal rats. Urinary sodium, potassium, prostaglandin E2 and kallikrein excretion was significantly increased after magnesium lithospermate B administration, whereas excretion of urinary 6-keto-prostaglandin F1 alpha and thromboxane B2 was unchanged. Rats administered with the drug also revealed a slight elevation of plasma renin activity and the levels of angiotensins I and II. Plasma aldosterone was decreased slightly. No significant changes were observed in angiotensin-converting enzyme or blood pressure.  相似文献   
27.
Between January 1993 and December 2001, we employed percutaneous cardiopulmonary support (PCPS) in 35 patients. PCPS was used for postcardiotomy in 25 of these patients who could not be weaned from cardiopulmonary bypass (CPB) because of severe cardiogenic shock. In the other 10 patients, PCPS was used for a non-surgical disease. Twenty-nine patients (82.9%) were weaned from PCPS, and 28 (80.0%) survived. The other 7 patients (20.0%) died due to postoperative complications. The causes of death were multiple organ failure (MOF) due to wound bleeding, low cardiac output syndrome (LOS), myonephropathic metabolic syndrome (MNMS) with severe lower limbs ischemia, cerebrovascular accident (CVA), and sepsis. The first cause for the complications was postoperative sustained severe heart failure. To improve the survival rate, it was necessary to prevent bleeding and begin PCPS at an earlier stage.  相似文献   
28.
Lobular carcinoma of the male breast is very rare, because lobules do not exist in the male mammary gland. Seven cases of lobular carcinoma of the male breast have been reported in Europe and U.S.A., although no case in Japan. We encountered a very rare case of the lobular carcinoma of 74-year-old male breast. Histopathological examinations of both primary tumor and recurrent tumors of the skin led to the diagnosis of lobular carcinoma.  相似文献   
29.
To investigate the pathophysiological role of anti-GM1 antibody in Gullain-Barre syndrome (GBS), we reviewed sequential nerve conduction studies of 345 nerves in 34 GBS patients. Statistically significant correlation between IgG anti-GM1 antibodies and electrodiagnoses was found. Sixteen IgG anti-GM1-positive patients were classified as having acute motor sensory axonal neuropathy (AMAN or AMSAN) (12 patients), as having acute inflammatory demyelinating polyneuropathy (AIDP) (3 patientsrpar;, or as undetermined (1 patient) by electrodiagnostic criteria. Besides axonal features, there was rapid resolution of conduction slowing and block. In 3 patients initially diagnosed as having AIDP, conduction slowing was resolved within days, and 1 of them and 3 AMAN patients showed markedly rapid increases in amplitudes of distal compound muscle action potentials that were not accompanied by prolonged duration and polyphasia. The time courses of conduction abnormalities were distinct from those in IgG anti-GM1-negative AIDP patients. Rapid resolution of conduction slowing and block, and the absence of remyelinating slow components, suggest that conduction failure may be caused by impaired physiological conduction at the nodes of Ranvier. Reversible conduction failure as well as axonal degeneration constitutes the pathopsiological mechanisms in IgG anti-GM1)positive GBS. In both cases, immune-mediated attack probably occurs on the axolemma of motor fibers.  相似文献   
30.
We report the results of reduced-intensity unrelated cord blood transplantation (RI-UCBT) in patients with advanced malignant lymphoma. Twenty patients (median age, 46.5 years; range, 27-66 years) underwent RI-UCBT with a preparative regimen consisting of fludarabine 125 mg/m2 , melphalan 80 mg/m 2 , and 4 Gy of total body irradiation. The median infused total cell dose was 2.75 x 10(7)/kg (range, 2.3-3.4 x 10(7)/kg). Graft-versus-host disease (GVHD) prophylaxis was composed of cyclosporine or tacrolimus alone. Fifteen patients achieved primary neutrophil engraftment after a median of 20 days. Eight patients developed grade II to IV acute GVHD, and 2 developed chronic GVHD. Of the 16 patients with evaluable disease, 10 achieved a complete response. Primary disease recurred in 1 patient, and transplant-related mortality within 100 days occurred in 8 of 20 patients. The estimated 1-year probability of progression-free survival was 50%. These data suggest that RI-UCBT is a feasible option for patients with refractory lymphoma who lack an HLA-matched donor.  相似文献   
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