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101.
The human liver contains significant numbers of innate immune cells, such as natural killer (NK) cells and natural killer T (NKT) cells, which express both T-cell receptors and NK-cell receptors simultaneously. It has been suggested that the innate immune system plays a crucial role in the liver. In this report, the distribution of NK and NKT cells in the liver and peripheral blood of two patients with drug-induced fulminant hepatic failure (FHF) who had undergone living donor liver transplantation was examined. In both the liver and peripheral blood, the proportions of NK and NKT cells markedly decreased compared with those in healthy donors. It was also revealed that, unlike murine NKT cells, human CD56(+) T cells and CD57(+) T cells did not constitutively express CD28, which is one of the important costimulatory molecules on T cells. Additionally, the residual CD56(+) T cells and CD57(+) T cells in the patients expressed more CD28 than in controls. This result suggests that NKT cells might be more activated in FHF. Although the accumulation of further cases is required, it is suggested that both NK and NKT cells might be involved in hepatic injury in FHF.  相似文献   
102.
We report a case of somatostatinoma of the ampulla of Vater associated with von Recklinghausen's disease in a 44-year-old woman. On admission the patient was jaundiced, and percutaneous Cholangiodrainage was performed. Cholangiography revealed stenosis of the common bile duct at the lower end Duodenoscopy showed a yellowish tumor of the ampulla of Vater, and the biopsy specimens showed no malignant cells. Pylorus-preserving pancreaticoduodenectomy was performed. Histologically, the tumor was composed of small round cells with a solid or trabecular pattern and with multiple psammoma bodies. Immunohistochemical examination showed that the tumor cells stained for somatostatin. Genomic examination showed neither K-ras nor p53 gene mutations of the resected specimen.  相似文献   
103.
104.
Bone lesions in elderly multiple myeloma   总被引:2,自引:0,他引:2  
We investigated the incidence of bone lesions in elderly cases of multiple myeloma (MM) and the course of those lesions, and also evaluated the relationships of skeletal symptoms with prognostic factors, and prognosis. The subjects were 146 patients, aged 65 years or more (median age 74, range 65-97 year), who were admitted to 11 institutions between January, 1988 and December, 1997. They consisted of 64 men and 82 women. The disease type was IgG type in 88 patients, IgA type in 37 patients, Bence-Jones (BJ) type in 17 patients, IgD type in three patients, and non-secretory type in one patient. Bone lesions in elderly MM patients were compared with those in 65 non-elderly MM patients. Skeletal symptoms were noted in 104 patients, and bone pain in 75 patients at the time of diagnosis. The bone lesions were evaluated as only osteolytic lesions in 26 patients, osteolytic lesions + osteoporosis in 23 patients, only osteoporosis in 2 patients and pathologic bone fractures in 53 patients. The occurrence rate of osteoporosis plus osteolytic lesion was higher in elderly patients (63.5%) than that in non-elderly patients (NE-MM group) (28.3%) (p < 0.0001). The bone lesions were most often observed in lumbar vertebrae (58.7%), cranial bone (56.7%), thoracic vertebrae (40.4%) and ribs (27.9%). The occurrence rate of bone lesion in lumbar vertebrae was higher in elderly patients (58.7%) than that in non-elderly patients (22.6%) (p < 0.0001). The life activities were limited in 71 patients because of the bone lesions. The relationship between the prognostic factors of MM and bone lesions was evaluated. There was a significant difference in the serum Ca level between patients with and without bone pain (P < 0.0001) and between those with and without pathologic bone fracture (P < 0.01). There was a significant difference in the appearance rate of plasma cells in the bone marrow between the patients with and without bone lesions (P < 0.05), between those with and without bone pain (P < 0.01), and between those with and without pathologic fracture (P < 0.05). There was a significant difference in the serum beta 2-microglobulin level between the patients with and without bone pain, and between those with and without pathologic fracture. There were no significant differences in survival times between elderly MM patients with and without bone lesions, bone pain and pathological bone fractures, while significant differences of survival times were found between non-elderly MM patients with and without bone lesions, bone pain and pathological bone fractures (P < 0.05, each). These data suggest that there are some differences in bone lesions between elderly and non-elderly MM patients.  相似文献   
105.
Kimura’s disease is characterized by subcutaneous masses, eosinophilia, and markedly elevated serum immunoglobulin E, suggesting that T helper (Th)2 cells may play a role in the pathogenesis. We investigated Th2 cytokine synthesis by mononuclear cells and possible Th1/Th2 subpopulations in Kimura’s disease. Peripheral blood samples were obtained from seven patients with Kimura’s disease and CD4+ T-cell subpopulations separated by CD45RO and CD62L were isolated. Purified cells were stimulated with PHA or anti-CD3 mAb, and the cytokine levels were measured by Cytometric Bead Array kit. Peripheral blood mononuclear cells in the majority of the patients produced Th2 cytokines such as interleukin (IL)-3, IL-4, IL-5, IL-13 or GM-CSF higher than those of controls. The ratio of CD45RO+ CD62L+ cells in CD4+ T cells was increased in six out of seven patients compared to age-matched controls. Especially, patient 1 had remarkably increased levels of CD45RO+ CD62L+ population in CD4+ T cells. In addition, IL-4 production levels by CD45RO+ CD62L+ CD4+ T cells of patients 1 and 2 were higher than those of their CD45RO+ CD62L CD4+ T cells, in the same manner as those by a normal control. Taken together, the synthesis of Th2 cytokines and CD62L-positive subpopulation in CD45RO+ CD4+ T cells, which may represent characteristics of Th2, are increased in patients with Kimura’s disease, suggesting that deviation to Th2 may involve in pathogenesis of the disease.  相似文献   
106.
Purpose:To evaluate the feasibility for the detection of slight contrast effects after intravenous administration of single dose gadolinium-based contrast agent (IV-SD-GBCA), the time course of the GBCA distribution up to 24 h was examined in various fluid spaces and brain parenchyma using 3D-real IR imaging and MR fingerprinting (MRF).Methods:Twenty-four patients with a suspicion of endolymphatic hydrops were scanned at pre-administration and at 10 min, 4 and 24 h post-IV-SD-GBCA. 3D-real IR images and MRF at the level of the internal auditory canal were obtained. The signal intensity on the 3D-real IR image of the cerebrospinal fluid (CSF) in the cerebellopontine angle cistern (CPA), Sylvian fissure (Syl), lateral ventricle (LV), and cochlear perilymph (CPL) was measured. The T1 and T2 values of cerebellar gray (GM) and white matter (WM) were measured using MRF. Each averaged value at the various time points was compared using an analysis of variance.Results:The signal intensity on the 3D-real IR image in each CSF region peaked at 4 h, and was decreased significantly by 24 h (P < 0.05). All patients had a maximum signal intensity at 4 h in the CPA, and Syl. The mean CPL signal intensity peaked at 4 h and decreased significantly by 24 h (P < 0.05). All patients but two had a maximum signal intensity at 4 h. Regarding the T1 value in the cerebellar WM and GM, the T1 value at 10 min post-IV-GBCA was significantly decreased compared to the pre-contrast scan, but no significant difference was observed at the other time points. There was no significant change in T2 in the gray or white matter at any of the time points.Conclusion:Time course of GBCA after IV-SD-GBCA could be evaluated by 3D-real IR imaging in CSF spaces and in the brain by MRF.  相似文献   
107.

Background

The aim of this study was to evaluate the usefulness of noise reduction procedure (NRP), a function in the new image processing for chest radiography.

Methods

A CXDI-50G Portable Digital Radiography System (Canon) was used for X-ray detection. Image noise was analyzed with a noise power spectrum (NPS) and a burger phantom was used for evaluation of density resolution. The usefulness of NRP was evaluated by chest phantom images and clinical chest radiography. We employed the Bureau of Radiological Health Method for scoring chest images while carrying out our observations.

Results

NPS through the use of NRP was improved compared with conventional image processing (CIP). The results in image quality showed high-density resolution through the use of NRP, so that chest radiography examination can be performed with a low dose of radiation. Scores were significantly higher than for CIP.

Conclusion

In this study, use of NRP led to a high evaluation in these so we are able to confirm the usefulness of NRP for clinical chest radiography.  相似文献   
108.
European Journal of Clinical Microbiology & Infectious Diseases - The aim of this study is to clarify the characteristics of gram-negative bacteremia (GNB), including extended-spectrum...  相似文献   
109.
Micronodular thymoma with lymphoid stroma (MNT) is a rare thymic epithelial neoplasm subtype characterized by a micronodular tumor cell growth pattern and abundant lymphoid stroma. Micronodular thymic carcinoma with lymphoid stroma (MNCA) is considered as a malignant counterpart of MNT and exhibits a growth pattern similar to that of MNT but has histologic features reminiscent of thymic squamous cell carcinoma, such as cytologic atypia and CD5 and CD117 immunoexpression. Although both MNT and MNCA are characterized by abundant lymphoid stroma, it remains unknown whether there are differences in infiltrating lymphocytes between MNT and MNCA. We analyzed the immune microenvironment profile in eight MNT and three MNCA cases. The cell density of CD8-positive T cells was significantly higher in MNT than in MNCA, whereas that of FOXP3-positive T cells was significantly higher in MNCA than in MNT. There was no significant difference in the cell density of programmed death protein 1-positive T cells and programmed death ligand 1 expression between the MNT and MNCA cases. Our findings indicated that the immune microenvironment of MNCA differed from that of MNT and, compared with the T-cell profile of MNT, that of MNCA was more suppressive to patients′ antitumor immune response.  相似文献   
110.
Background: The optimal timing of surgical resection of liver metastasis remains controversial, and guidelines regarding the upper limits of operative indications have not yet been defined. Surgical indication for metastasis from colorectal cancer (CLM) based on results of preoperative chemotherapy and RNF8 was investigated. Methods: Differences in CLM size on CT were evaluated as shrinkage rate/day by dividing tumor shrinkage rates by the interval in days between CT. Levels of RNF8 of resected colorectal cancer and CLM frozen specimen were detected. Results: When the cut line for shrinkage rate at 12 weeks was set at 0.35%, disease-free survival was significantly better in patients with a shrinkage rate >0.35% vs. ≤0.35% (p=0.003). RNF8 expression was significantly higher in Tis (p=0.001). In liver metastasis, RNF8 expression level was significantly lower in patients with partial response to FOLFOX than with stable disease, (p=0.017). Conclusions: A strategy of FOLFOX administration for 12 weeks to patients with low RNF8 expression and hepatectomy planned after 4 weeks rest may be accepted as the best therapeutic option for treating CLM.  相似文献   
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