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81.
Sputum cytology was performed in 179 cases of squamous-cell carcinoma of the lung; 134 cases were diagnosed as positive. There were no significant differences in diagnostic accuracy of sputum cytology between tumors sizes. In cases with tumors extending proximally into the main, lobar, or segmental bronchi, the diagnostic accuracy of sputum cytology was significantly higher than in cases where the proximal invasion of tumor was limited to the peripheral bronchi. In cases with tumors 3 cm or less in diameter, when tumors extended proximally into main, lobar, or segmental bronchi, the diagnostic accuracy of sputum cytology was significantly higher than in cases with tumors extending proximally into subsegmental or subsubsegmental bronchi. In peripherally located squamous-cell carcinoma, in cases in which the tumor arose in subsegmental or subsubsegmental bronchi, carcinoma could be detected by sputum cytology even when it was roentgenographically occult. 相似文献
82.
F1 cynomolgus monkeys bred in captivity and thought to be "SPF" had latent cytomegalovirus (CMV) infection although less frequently than in wild-born monkeys. Latent CMV could be activated under severe immunosuppression by inoculation with a certain strain of varicella-zoster virus (VZV) as shown in a previous study. We carried out further experiments using live and formalin-inactivated VZV in F1 monkeys which were sero-positive for CMV, but not for any other viruses. The results showed that both live and inactivated VZV were equivalent in permitting activation of latent CMV, suggesting that the VZV inoculum merely played an immunogenic, but not any virological, role in this case. Captive F1 monkeys, however, carried fewer CMV, and/or resisted CMV reactivation more than the wild monkeys in the previous studies, judging from the time required for generalized CMV infection to become expressed. 相似文献
83.
Mitsui A Hamuro J Nakamura H Kondo N Hirabayashi Y Ishizaki-Koizumi S Hirakawa T Inoue T Yodoi J 《Antioxidants & redox signaling》2002,4(4):693-696
Transgenic (Tg) mice overexpressing human thioredoxin (TRX), a small redox-active protein, were produced to investigate the role of the protein in a variety of stresses. Bone marrow cells from TRX-Tg mice were more resistant to ultraviolet C-induced cytocide compared with those from wild type (WT) C57BL/6 mice. TRX-Tg mice exhibited extended median and maximum life spans compared with WT mice. Telomerase activity in spleen tissues in TRX-Tg mice was higher than that in WT mice. These results suggest that overexpression of TRX results in resistance against oxidative stress and a possible extension of life span without apparent abnormality in mammals. 相似文献
84.
Characterization and expression of cDNA encoding coproporphyrinogen oxidase from a patient with hereditary coproporphyria 总被引:2,自引:1,他引:2
Fujita Hiroyoshi; Kondo Masao; Taketani Shigeru; Nomura Nakao; Furuyama Kazumichi; Akagi Relko; Nagai Tadashi; Terajima Masanori; Galbraith Richard A.; Sassa Shigeru 《Human molecular genetics》1994,3(10):1807-1810
Hereditary coproporphyria (HCP) is an acute hepatic porphyriawith autosomal dominant inheritance, but with a variable degreeof clinical expression. Molecular cloning, sequencing and expressionof the defective gene for coproporphyrinogen oxidase (CPO) ina patient with HCP were carried out. Enzyme assays revealedthat CPO activity in EBV-transformed lymphoblastoid cells fromthe proband and one of her sisters was 相似文献
85.
86.
Alice H. Dodge Mark Brownfield Ian A. Reid Tadashi Inagami 《Developmental dynamics》1988,182(4):347-352
Diethylstilbestrol (DES) treatment of a male Syrian hamster resulted in the development of a renal tumor and its widely scattered scrosal metastases. Cells in both the primary tumor and metastatic nodules contained secretory granules. The tumors were transplanted serially into DES-supported and non-DES-supported host hamsters until DES-independent tumors developed. Rabbit antiserum to mouse salivary renin and rabbit antiserum to rat kidney resin were reacted with sections of the primary tumor, metastatic nodules, and all transport tumors. The sections were stained by the PAP and Vector-ABC-AP procedures. Renin-positive material was observed in all tumors. Plasma renin activity (PRA) was determined for the host hamsters carrying the renal tumor transplants and compared to the PRA values that had been determined for normal non-DES-treated male and female hamsters. It was found that the average PRA values of host hamsters carrying the tumor transplants were significantly higher than the normal PRA ralues. 相似文献
87.
Thromboplastic and fibrinolytic activities of V2 and V7 carcinomas, the two transplantable rabbit tumors of the same viral origin, were studied in relation to fibrin deposition and thrombus formation in the tumors. Thromboplastic activity of V7 carcinoma was comparatively high, while that of V2 carcinoma was as low as that of muscle tissue. More fibrin deposits in the stroma and more thrombi in the small vessels were found at the advancing border of V7 carcinoma than that of V2 carcinoma. These differences might be associated with higher thromboplastic activity of V7 carcinoma than that of V2 carcinoma. Fibrinolytic activity of both tumors was high and it was confirmed to be localized in the tumor cells by Todd's method. Fibrin deposits in the stroma were found more abundantly somewhat apart from the advancing border of the tumor nests of both tumors. It was suggested that plasmin activated by plasminogen activator released locally from the tumor cells might digest fibrin deposited in the stroma just close to the tumor nests. 相似文献
88.
The relationship of gastrointestinal endocrine cells to gastric epithelial changes with special reference to gastric cancer. 总被引:4,自引:0,他引:4
Using advanced gastric adenocarcinoma and carcinoid as human material and gastric adenocarcinoma in rats induced by MNNG and in mice by localized X-irradiation of the stomach as experimental material, a pathological study was made on the relationship of gastric endocrine cells to gastric cancer. The results of the present study suggest that most of the endocrine cells in the cancer tissue are derived from the differentiation of cancer cells. Therefore, the following three may be given as the aformentioned relationship, that is, 1) carcinoid of endocrine cell origin, 2) endocrine cell carcinoma showing undifferentiated adenocarcinoma, and 3) endocrine cell cloning developed from the differentiation of cancer cell of adenocarcinoma. There is the possibility that most of 2) are of 3) origin and thus 2) and 3) should be discriminated from 1), having a functioning tumor in rare cases. The significance of reactive hyperplasia of endocrine cells in the non-metaplastic mucosa of the stomach around cancer and atypical epithelium is not yet determined, but that of EC cell seems at least to be related with the development of intestinal metaplasia in the gastric mucosa. 相似文献
89.
Takanori Hirose Tadashi Hasegawa Kunihiko Seki Peng Yang Toshiaki Sano Hiroshi Morizumi Masaru Tsuyuguchi 《Ultrastructural pathology》1996,20(5):451-456
A case is reported of atypical glomus tumor occurring in the posterior inferior mediastinum of a 26-year-old woman complaining of severe back pain. The tumor was composed of atypical small, round tumor cells with scattered mitotic figures. In addition to sheet-like, diffuse proliferation of the tumor cells, some areas of the tumor contained small “glo-moid” cells arranged in organoid and hemangiopericytoma-like patterns. Immunohistochemically, many tumor cells were positive for muscle-type actins and a few cells were focally positive for desmin. Ultrastructural studies revealed smooth muscle features of tumor cells, that is, pinocytotic vesicles, external laminas, dense plaques, and occasional thin filaments with dense bodies. The patient remained well for 5 years and 4 months after the operation without additional radiation and chemotherapy. The tumor was diagnosed as an atypical, or low-grade malignant, glomus tumor morphologically. It seems important to recognize the presence of this type of tumor in sites other than extremities and to differentiate it from other malignant small, round cell tumors. 相似文献
90.
Chong-Su Cho Tadashi K
moto Akira Nakagami Tohru Kawai 《Macromolecular chemistry and physics.》1979,180(8):1951-1959
Ionic polymer-polymer interaction was studied in aqueous solution for poly(L -lysine) (PLL) and sulfated poly(vinyl alcohol) (PVS) as functions of pH, the degree of sulfation, the functional unit mole ratio of the two polymers and temperature by means of circular dichroism and viscosity measurements. In all the cases studied, strong inter-polymer complexes were formed at the functional unit mole ratio (VS)/(LL) higher than 1. Although PLL itself is well known to take the α-helical conformation at such a high pH as 11, the PLL conformation in the PLL/PVS complexes did not depend on pH but on the degree of sulfation: at room temperature, PLL took random coil conformation in PLL/PVS-25 (25: degree of sulfation in mole-%) and PLL/PVS-30, and the α-helical conformation (helicity of 70%) in PLL/PVS-46 and PLL/PVS-95. Models for the complex structures are postulated. Methanesulfonic acid did not influence the conformational transition of PLL, supporting that a polymer effect took place in the complex formation between PLL and PVS. Thermal effect on the PLL conformation in the complex is also discussed. 相似文献