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81.
We report a case of a 10-month-old boy who died of severe hepatic failure after a prolonged course of infectious mononucleosis. He also presented interstitial pneumonitis, meningoencephalitis and aplastic anaemia. Epstein-Barr virus (EBV)-specific cytotoxic T lymphocyte (CTL) activity had not been detected in his peripheral blood during the course of the illness. Studies of his mother revealed a severe reactivation pattern of anti-EBV antibodies and decreased EBV-specific CTL activity. An X-linked familial susceptibility to EBV infection such as X-linked lymphoproliferative syndrome (XLP) might be associated with his fatal EBV infection.  相似文献   
82.
We have investigated the dose rate effects on cell damage caused by photon-beam irradiation. During a relatively long dose-delivery time with a low dose rate, lesions created in cells may undergo some reactions, such as DNA repair. In order to investigate these reactions quantitatively, we adopted the microdosimetric–kinetic (MK) model and deduced a cell surviving fraction (SF) formula for continuous irradiation. This model enabled us to estimate the SF from dose and dose rate. The parameters in the MK model were determined so as to generate the SF, and we attempted to evaluate the dose rate effects on the SF. To deduce the cell-specific parameters in the SF formula, including the dose rate, we performed a split-dose experiment and a single-dose experiment with a constant dose-delivery time (10 min) (to retain the condition for equivalent behavior of cell lesions) by means of a clonogenic assay. Then, using the MK model parameters, the SFs were reproduced for a variety of dose rates (1.0, 0.31, 0.18, 0.025 and 0.0031 Gy/min) and were compared with reported experimental data. The SF curves predicted by the MK model agreed well with the experimental data, suggesting that the dose rate effects appear in the kinetics of cell lesions during the dose-delivery time. From fitting the analysis of the model formula to the experimental data, it was shown that the MK model could illustrate the characteristics of log-SF in a rectilinear form at a high dose range with a relatively low dose rate.  相似文献   
83.
84.
The treatment of patients with aggressive subclasses of myelodysplastic syndrome (MDS) remains a challenge. In an effort to improve the survival of patients with refractory anemia with excess blasts (RAEB), RAEB in transformation (RAEB-t), or acute myelogenous leukemia transformed from MDS (MDS-AML), we conducted a small trial in which 28 such patients were treated with low-dose cytosine arabinoside (LDAraC) followed by administration of macrophage colony-stimulating factor (M-CSF). The overall rate of response to the treatment was 61%, including 39% with a complete response, which is higher than rates obtained in previous studies in which LDAraC alone was administered to patients with MDS. Median survival was 23.5 months in cases of RAEB, 16.7 months in cases of RAEB-t, and 19.7 months in cases of MDS-AML. The overall survival of the study group appeared to be prolonged in comparison with a historical control group of patients treated with LDAraC alone. It is suggested that M-CSF added to the administration of LDAraC plays an active role in the therapy. No therapy-related death occurred. Some unique actions of M-CSF were suggested in this trial. It is concluded that therapy with LDAraC + M-CSF is a useful treatment option for patients with aggressive subclasses of MDS and MDS-AML to provide better response and survival.  相似文献   
85.
Summary. A cell line designated SKM-1 was newly established from leukaemic cells of a 76-year-old Japanese male patient with monoblastic leukaemia following myelodysplastic syndrome (MDS). The cells were obtained from peripheral blood of the patient when he lost multiple point mutations of ras genes with acquisition of chromosomal abnormalities during disease progression in MDS. The cells grew as a single floating cell, and have been continuously growing with the morphological characteristics of immature monoblasts by serial passages during the past 42 months with a doubling time of about 48 h. By cytochemical analysis. the cloned cells were positive for butyrate esterase, but negative for the Epstein-Barr virus associated nuclear antigen. Phenotypic analysis revealed the expression of myelomonocyte specific antigens such as CD4, CD13, CD33 and HLA-DR. Cells from the primary peripheral blood and those from SO passages of the SKM-1 cell line both possessed no activated ras genes but showed karyotype abnormalities with 46.XY, del(9)(q13;q22), der(17) t(17:?)(p13:?). The SKM-1 cells have two mutations in p53 gene and overexpress the pS3 products. This cell line may contribute to a better understanding of molecular mechanisms in the progression from MDS to myelogenous leukaemia.  相似文献   
86.
The purpose of this study was to examine the effects of celecoxib on matrix metalloproteinases (MMP-1 and MMP-3), nitric oxide (NO), and the phosphorylation of nuclear factor-κB (NF-κB) and three mitogen-activated protein kinases (MAPKs), (p38, JNK and ERK) in human articular chondrocytes from normal, osteoarthritis, and rheumatoid arthritis cartilages. Celecoxib at 100 nM reduced the IL-1β-induced productions of MMP-1, MMP-3, iNOS, and NO, whereas indomethacin at 100 nM showed no effect. The additional stimulation of prostaglandin E2 (PGE2) failed to restore those productions, while the production of PGE2 were reduced by 1 and 10 μM but not 100 nM of celecoxib. The inhibitors of NF-κB, JNK and p38, but not ERK, decreased IL-1β-enhanced MMP-1, MMP-3 and NO production, respectively, and 100 nM celecoxib down-regulated the phosphorylation of NF-κB and JNK but has no effect on either p38 or ERK. Celecoxib has inhibitory effects on MMP-1, MMP-3 and NO productions, suggesting the protective roles directly on articular chondrocytes. Despite the COX-2 selectivity, celecoxib affects those productions via not PGE2 but NF-κB and JNK MAPK.  相似文献   
87.
Four kinds of human cancer cell lines and one mouse cancer cell line were inoculated into the subepithelial area of the anorectum of female nude mice. Among the cell lines, two cell lines (KATO III and Lu 135) showed the potential enforcement of atypical changes in the adjacent mouse anorectal epithelium. Moreover, the submucosal invasion of the malignant transformed cells of the mouse epithelium was demonstrated in specimens obtained from three KATO III-inoculated mice. This exciting and novel phenomenon clearly demonstrates the need to change the present general concept of a single-cell origin of cancer tissue. This valuable and novel discovery may change the basis of oncology research while also providing new ideas for projects to investigate the mechanisms of carcinogenesis from several aspects such as molecular biology, cell biology, and pathology. Moreover, the novel experimental design itself is also extremely useful as a simple model for investigating the mechanisms of oncogenesis.  相似文献   
88.
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   
89.

Objective

To investigate anatomic features of the inferior oblique nerve (IObN) by high-resolution magnetic resonance (MR) imaging and cadaveric dissection.

Methods

This study enrolled 100 consecutive outpatients, who underwent 3.0 T MR imaging equipped by the 32-channel head coil. The T2-weighted imaging data of IObN were extracted for analysis and compared with the findings of microsurgical dissection in 14 orbits.

Results

50 male and 50 female subjects allotted to the imaging study were aged from 11 to 78 years. In 94 % sides, the IObN was found to separate from the inferior rectus muscle (IRM) at the level just behind to the posterior pole of the bulb. At the midpoint of the IObN part coursing along the orbital floor and above or adjacent to the infraorbital nerve and artery complex, the mean distance from the lateral margin of the IRM was 1.0 mm on the right and 0.9 mm on the left. The IObN showed upward direction change just below the belly of the inferior oblique muscle and innervated to it at the equator level in 78 sides on the right and 89 on the left. Dissected specimens revealed the consistent morphological findings of the IObN.

Conclusions

The IObN seems to be a relatively consistent structure. Anatomic information on the IObN and surrounding structures that are provided by high-resolution MR imaging can be a help for safe surgery.  相似文献   
90.
The optimization of photorefractivity (PR) based on a poly(N‐vinylcarbazole) (PVCz) composite devise is proposed from the perspectives of chemistry and physics. The device's PR chemistry (dependence of PVCz's molecular weight) and physics (dependence of grating periodicity and laser wavelength) are studied. Increasing the molecular weight of PVCz from 23 000 to 1 270 000 g mol?1 significantly increases diffraction efficiency, grating build‐up speed (inverse of response time), and sensitivity. Narrowing grating period from 5.1 to 1.1 μm gives faster response time and larger optical gain. Shorter wavelength of writing laser from 633 to 532 nm provides higher diffraction efficiency, faster response time, and larger optical gain.

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