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141.
Park SS Kim BK Kim CJ Kim WS Kim IO Park KW Shin HY Ahn HS 《Journal of Korean medical science》2000,15(4):475-477
Following improvements in therapy for childhood malignancies, the striking increase in survival rate over the past 30 years has led to the increase risk of developing second malignant neoplasms (SMNs). We report a case of colorectal carcinoma as a SMN, following treatment for rhabdomyosarcoma. The patient was diagnosed with rhabdomyosarcoma of the urinary bladder at his age of three years, and developed adenocarcinoma in the colon 13 years later. Histologic examination of the surgical specimen revealed adenocarcinoma involving the rectosigmoid area with radiation colitis in its background. The tumor cells showed strong immunoreactivity for p53 protein, suggesting the role of irradiation and p53 mutation in carcinogenesis. This case emphasizes the need for dose observation in survivors of early childhood malignancies treated with radiation and multiagent chemotherapy. 相似文献
142.
Lee YS Kim KS Chung YS Cheon DS Jung SK Park KS Na BK Jee YM Kim DS Yoon JD Song CY Lee KH 《Archives of virology》2002,147(9):1711-1720
Summary. We have evaluated PCR–RFLP as a practical method for rapid typing of enteroviruses causing aseptic meningitis in Korea. Through
blind examination of 80 clinical isolates from patients with aseptic meningitis, we have compared the results of conventional
serotyping with PCR–RFLP based genotyping, which was developed for this study. Among the 80 case isolates, which had been
previously typed by routine neutralization test, only 42 cases (52.5%) were matched with typing by PCR–RFLP. The result clearly
demonstrated that the enterovirus serotype does not coincide with the genotype. Therefore, the classification of enteroviruses
by genotyping with PCR–RFLP, although rapid and simple, may be complicated by regional or seasonal differences. However, the
PCR–RFLP method developed in this study is applicable to the epidemiological study of enteroviruses when regional or seasonal
differences exist, and is useful in identifying the source of an infection.
Received August 6, 2001; accepted April 15, 2002 Published online July 10, 2002 相似文献
143.
Radiologic findings of Mirizzi syndrome with emphasis on MRI 总被引:6,自引:0,他引:6
We have reported a case of Mirizzi syndrome preoperatively diagnosed using MR cholangiopancreatography. MRCP and T2-weighted image using a single-shot fast spin-echo sequence accurately depicted all components of Mirizzi syndrome, including impacted stone in the neck of the gallbladder compressing the common hepatic duct and wall-thickening of the gallbladder without any evidence of malignancy. The combination of MRCP and T2-weighted image can be counted on to replace conventional modalities of diagnosing Mirizzi syndrome without any loss of diagnostic accuracy. 相似文献
144.
Sclerosing hemangiomas of the lung are benign neoplasms of uncertain histogenesis. We analysed two cases of sclerosing hemangiomas of the lung with histochemistry and electron microscopy. They had a variegated histologic appearance characterized by an admixture of solid, hemorrhagic, papillary and sclerotic lesions. Characteristic uniform round cells, unique to this tumor, were found within the stroma in all lesions. In the electron microscopic examination, we found Weibel-Palade bodies like small bodies in the tumor cells. We suspect hypothesis originating in the endothelial cell can not be completely excluded yet. Sclerosing hemangioma is a distinct clinicopathologic entity and should be distinguished from other benign neoplasms or inflammatory lesions of the lung. 相似文献
145.
146.
Seung Yong Park Hisashi Arase Keisuke Wakizaka Nakami Hirayama Shigehiro Masaki So-Ichiro Sato Jeffrey V. Ravetch Takashi Saito 《European journal of immunology》1995,25(7):2107-2110
The function of the Fc receptors γ chain (FcRγ) for the expression of the T cell receptor (TCR) complex and for T cell development, especially for T cells localized in epithelia, was investigated by analyzing FcRγ-deficient mice. In wildtype mice, CD8αα+β?TCRαβ+ T cells of intestinal intraepithelial lymphocytes (i-IEL) utilized CD3ζ homodimers and ζ-FcRγ heterodimers, whereas CD8α α+β?TCRγδ+ i-IEL used ζ-FcRγ and FcRγ homodimers in the TCR complex. On the other hand, these T cells in FcRγ-deficient mice contained only ζ homodimers. The surface expression of the TCR complex was reduced in CD8αα+β?i-IEL and dendritic epidermal T cells (DETC) in these mice, whereas the development of these T cells was normal. The degree of reduction appeared to depend on the expression level of FcRγ. In contrast to these populations, TCRγδ+ intraepithelial T cells in reproductive organs (r-IEL) were dramatically decreased, suggesting that the development of r-IEL is FcRγ-dependent, probably due to the predominant usage of FcRγ homodimers in the TCR complex. These results indicate that the FcRγ chain contributes differently to the TCR expression and to the development of T cells localized in epithelia. 相似文献
147.
J. H. Lee S. S. Lee J. S. Park S. Lee M. H. Yang T. Y. Yoon 《Journal of Korean medical science》1995,10(6):399-405
Recent studies have suggested a probable association between Epstein-Barr virus (EBV) and nasal/nasopharyngeal T cell lymphomas but the role of oncogenes or tumor suppressor genes is poorly understood. We have studied the frequency of p53 expression and its relation to the EBV infection in 33 Korean patients with head and neck (H&N) lymphomas. All cases (23 B cell & 10 T cell) were immunostained for p53 protein using the mAb D07 (Novocastra) and the avidin biotin peroxidase method. EBER in situ hybridization was performed using a fluorescein conjugated EBV oligonucleotide probe (Dako). Among 33 lymphomas, 16 cases stained positively for p53 protein. P53 expression was frequent both in higher grade lymphomas and in advanced stage. Nine cases were EBER positive, EBER was more commonly found in T cell lymphomas than in B cell lymphomas (70% vs 8.7%). EBER positive lymphomas showed a higher frequency of p53 positivity than EBER negative lymphomas (78% vs 38%), although the difference was not statistically significant (p = 0.095). These findings indicate altered expression of p53 protein occurs in H&N lymphomas, especially in late event lymphoma progression and appears to play a role in the development of EBER positive T cell lymphomas. 相似文献
148.
A patient complying with the clinical criteria for brain death was studied by preenhanced computed tomography (CT). Preenhanced CT showed apparent increased density at the base of the brain along the course of the major arterial vessels, and abnormally dense-appearing deep venous structures, like those of contrast-enhanced CT. There was a diffuse decrease in brain density with a poorly delineated ventricular system. These CT findings were very characteristic. CT as a non-invasive method seems to be valuable in the diagnosis of brain death. The relevant literature is reviewed and mechanisms showing those CT findings are discussed. 相似文献
149.
D. Han J. H. Sohn Y. J. Cho Y. C. Jeon H. J. Kim K. N. Park S. J. Chang 《Journal of Korean medical science》1997,12(5):465-468
A flat depressed early colon cancer (FDEC) is characterized by non-polypoid growth pattern, no association of adenomatous tissues and a tendency of even small lesions toward submucosal invasion and lymph node metastasis. It supports de novo carcinogenesis of colorectal cancer, although most colorectal cancers arise in pre-existing adenoma (adenoma-carcinoma sequence). There have been few reports of small depressed cancers because of the difficulty in colonoscopic detection and the rapid development to ulcerating advanced cancers. We report a case of flat depressed early colon cancer confined to mucosa detected by indigo carmine contrast colonoscopy. 相似文献
150.
Fracture behavior of dental composite resins. 总被引:2,自引:0,他引:2
Fracture toughness (KIC), critical stress intensity factor, and bending strength of 3 types of commercially available dental composite resins (macrofilled, hybrid and microfilled type) were determined using three point bend specimens. Acoustic Emission (AE), which is the generation of elastic wave due to the release of energy from the localized sources in material, was also detected during the fracture toughness test. Fracture surfaces were examined by scanning electron microscope. The fracture toughness values, AE patterns, and the nature of fracture surface were analyzed to understand fracture behavior of dental composite resins and fracture mechanism for each dental composite resin are proposed. 相似文献