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31.
N Ida S Sakurai T Hosaka K Hosoi T Kunitomo Y Matsuura M Kohase 《Journal of immunological methods》1990,133(2):279-284
An enzyme-linked immunosorbent assay has been developed to measure human interleukin-6. The assay, based on the avidin-biotin amplified two-step sandwich method, is quick (requiring 4.5 h), sensitive (detecting 9.5 pg/ml) and satisfactory in reproducibility and specificity. It shows good correspondence with the results of bioassays, and it is not affected by serum and plasma components. These results indicate that this ELISA is suitable for application to clinical samples, which is a major advantage over the widely used bioassays. 相似文献
32.
Mr N. Ishikawa S. Suda T. Sasaki T. Yamanishi H. Hosaka K. Yasuda H. Ito 《Medical & biological engineering & computing》1998,36(6):704-710
A system composed of a functional continuous magnetic stimulator (FCMS) and a saddle-type coil has been developed for non-invasive
treatment of urinary incontinence, especially stress incontinence and urge incontinence. The FCMS conditions were as follows:
2 kW maximum electrical power consumption, 800 V maximum capacitor voltage, 720 μs pulsewidth (180 μs rise time), and 5–30
Hz frequency. A frequency between 5 and 10 Hz is used to treat urge incontinence and a frequency between 25 Hz and 30 Hz is
used to treat urge incontinence. The coil (120 mm long, 90 mm wide and 50 mm thick) fits the most suitable region for this
treatment, the region from the anus to the perineum. The coil is cooled to maintain a coil temperature between 20 and 25°C
so that it can be used efficiently and safely. In experiments with anaesthetised dogs, it was confirmed that the urethral
pressure increased when the circumference of the perineum received continuous magnetic stimulation of 720 μs pulsewidth (180
μs rise time), 10Hz frequency and about 520 V capacitor voltage. This result suggests that magnetic stimulation can be effective
as a urinary incontinence therapy. 相似文献
33.
Osamu Kawamura Dian‐Sheng Wang Yi‐Xin Liang Akihiro Hasegawa Chika Saga Angelo Visconti 《Food and Agricultural Immunology》1994,6(4):465-467
A survey of AFM1 residues in 58 commercial milk powder samples was carried out using an enzyme‐linked immunosorbent assay (ELISA) based on a monoclonal antibody against aflatoxin M1 (AFM1). The samples were collected from the USA (10), China (28), Italy (14), New Zealand (3) and Poland (3). The ELISA was performed without the need for clean‐up procedures. The data revealed that 4 (US), 21 (Chinese) and 1 (Polish) samples were positive for AFM1, with an average of 95.5, 102.8 and 85.0 pg g‐1 of the AFM1respectively. 相似文献
34.
Ito Y Yoshida H Tomoda C Miya A Kobayashi K Matsuzuka F Yasuoka H Kakudo K Inohara H Kuma K Miyauchi A 《Pathology》2005,37(4):296-298
AIMS: Galectin-3, a member of the beta-galactoside binding family of lectins, has been regarded as a useful tool for discriminating malignant tumours from benign nodules of the thyroid, including the distinction between follicular carcinoma and adenoma. However, there are follicular tumours with unclear vascular or capsular invasion, which makes diagnosis more difficult. In this study, we investigated the relationship between galectin-3 expression and the degree of vascular or capsular invasion of follicular tumours. METHODS: We immunohistochemically investigated galectin-3 expression in 260 cases of follicular tumour with various degrees of vascular or capsular invasion classified into four categories. RESULTS: The galectin-3 expression level significantly increased with the degree of vascular or capsular invasion (p<0.0001). However, its diagnostic value for follicular carcinoma was not high because the sensitivity and specificity were 68.7% and 57.5%, respectively. CONCLUSIONS: Our findings suggest that galectin-3 plays a role in the transformation of follicular tumours from benign to malignant; however, when diagnosing follicular tumours, the presence of this protein should not be required for diagnosing malignant transformation in all cases. Therefore, we must conclude that galectin-3 should only be considered an adjuvant marker for follicular carcinoma. 相似文献
35.
Akihiro Umezawa Taketo Yamada Yuuto Ogawa Shigeru Kuramochi Yonosuke Watanabe 《Pathology international》1990,40(9):693-698
An autopsy case of acute megakaryocytic leukemia (AMKL) is presented. The bone marrow was hypercellular with proliferation of three lineages, especially megakaryocytes. Immunohistochemical examination revealed many platelet glycoprotein IIb/IIIa (GP IIb/IIIa)- positive blast cells in bone marrow. The proportion of the blasts was 26.4% by tissue hemogram. GP IIb/IIIa-positive blasts and megakaryoblasts were deposited massively in lymph nodes. lmmunohistochemistry against GP IIb/IIIa and tissue hemograms by paraffin section are needed to diagnose AMKL by postmortem examination, since the identification of ultra-structural platelet peroxidase in autopsy materials is difficult. 相似文献
36.
Koyama C Matsumoto H Sakai T Wakabayashi K Ito A Couch EF Inoue K 《Endocrine pathology》1995,6(1):67-75
A new cell line (TtT/GF) established from a murine pituitary thyrotropic tumor having characteristics similar to those of
pituitary folliculo-stellate cell (FS cell) was implanted into nude mice together with cells from a rat pituitary somatotrophic
tumor cell line (MtT/S) to determine whether the former enhances pituitary tumor growth. For as long as 2-3 mo after implantation,
MtT/S cells implanted either alone or together with fibroblasts formed either no tumors or only very small tumors in the nude
mice. In contrast all of the nude mice that had received MtT/S cells implanted together with TtT/GF cells developed large
tumors. Furthermore, the mice bearing the MtT/S and TtT/GF implants showed a significantly higher body weight and serum growth
hormone level than those bearing only MtT/S cells or a combination of MtT/S cells and fibroblasts. The TtT/GF cell line itself
had no tumorigenicity during the experimental period. Therefore, the TtT/GF cell line as a model of FS cells enhanced pituitary
endocrine cell tumor formation. Additionally, immunocytochemistry showed that TtT/GF cells positive for glial fibrillary acidic
protein (GFAP) or S-100 protein were present in the parenchymatous tissue elements or connective tissue surrounding the tumor
nests. In the parenchymatous tissue, the TtT/GF cells exhibited a stellate appearance and surrounded neighboring tumor cells
with their long cell processes. These results suggest that TtT/GF cells can serve as a model for pituitary FS cells, and are
capable of stimulating pituitary tumor growth either by modifying the microenvironment or producing growth factors. 相似文献
37.
Akihiro Yamamoto Takushi Naroda Susumu Kagawa Yoshihumi Umaki Yasumi Shintani Toshiaki Sano Hironobu Sasano 《Endocrine pathology》1993,4(3):165-168
A case of DOC-secreting adrenocortical carcinoma in a 66-year-old man is reported. He had hypertension, hypokalemia, suppressed PRA, and excessive serum levels of DOC. His serum aldosterone level was normal. The resected adrenal mass weighed 230 g. Histologically, the tumor was mainly composed of compact cells associated with necrosis and atypical mitoses. Invasion of venous structure, sinusoids, and capsule was also present. Immunohistochemically, P450 C21 (21 -hydroxylase) was positive in many tumor cells, and P450 C17(17 α-hydroxylase) was intensely positive in a relatively small number of tumor cells. The patient died 9 months after operation due to rupture of metastatic liver tumor.Endocr Pathol 4:165–168, 1993. 相似文献
38.
Kazunori Nagai Yoshihiko Sugiyama Tsuyoshi Hosaka Hikoichiro Takaya 《Pathology international》1973,23(1):59-73
Five autopsy cases of thrombotic microangiopathy, including 3 cases associated with acute promyelocytic leukaemia, were examined macroscopically, light-and electronmicroscopically.
The so-called hyaline thrombi In thrombotic microangiopathy were composed of fibrin and its degenerative products. Thrombocytes and other blood cells were not seen in the thrombi.
At the site of the formation of a thrombus, there was no conspicuous change in the walls of the capillaries and arterioles. It was considered, therefore, that the intravascular deposition of fibrin was the primary event in the development of thrombotic microangiopathy.
In regard to the distribution and morphologic findings, there was no basic difference between the microthrombi in cases associated with acute promyelocytic leukaemia and those without it.
The bone marrow and some other organs in cases of thrombotic microangiopathy associated with acute promyelocytic leukaemia macroscopically revealed a green colour. Many thrombi composed of leukaemic cells and fibrin were found in the pulmonary arteries of these cases. Furthermore, prominent erythrophagocytosis in the bone marrow and lymph nodes was a common finding in these cases. 相似文献
The so-called hyaline thrombi In thrombotic microangiopathy were composed of fibrin and its degenerative products. Thrombocytes and other blood cells were not seen in the thrombi.
At the site of the formation of a thrombus, there was no conspicuous change in the walls of the capillaries and arterioles. It was considered, therefore, that the intravascular deposition of fibrin was the primary event in the development of thrombotic microangiopathy.
In regard to the distribution and morphologic findings, there was no basic difference between the microthrombi in cases associated with acute promyelocytic leukaemia and those without it.
The bone marrow and some other organs in cases of thrombotic microangiopathy associated with acute promyelocytic leukaemia macroscopically revealed a green colour. Many thrombi composed of leukaemic cells and fibrin were found in the pulmonary arteries of these cases. Furthermore, prominent erythrophagocytosis in the bone marrow and lymph nodes was a common finding in these cases. 相似文献
39.
40.
Actin assembly is a crucial factor for superoxide anion generation from adherent human eosinophils 总被引:9,自引:0,他引:9
Suzuki M Kato M Hanaka H Izumi T Morikawa A 《The Journal of allergy and clinical immunology》2003,112(1):126-133
BACKGROUND: Cellular adhesion is crucial for eosinophil effector functions. OBJECTIVE: We sought to elucidate the role of the actin cytoskeleton in cellular adhesion and superoxide anion generation by human eosinophils. METHODS: Eosinophils were stimulated with platelet-activating factor (PAF) or complement component 5a on human serum albumin-coated plates with or without an actin-polymerization inhibitor, cytochalasin B (CB), or cytochalasin D (CD). Superoxide anion generation was measured on the basis of reduction of absorbance associated with cytochrome c.2 Eosinophil adhesion was assessed on the basis of eosinophil protein X content in adherent cells. Transient stimulus-induced increase of intracellular calcium and translocation of protein kinase C (PKC) betaII, PKC delta, PKC zeta, and p47 phagocyte oxidase (a component of nicotinamide adenine dinucleotide phosphate oxidase) were also investigated. RESULTS: CB, CD, or antibodies against CD18 (the beta2 chain of integrin, alphaMbeta2) inhibited stimulus-induced eosinophil superoxide anion generation. Stimulus-induced eosinophil adhesion was unaltered by CB, whereas it was significantly suppressed by CD or anti-CD18 antibodies. Transient PAF-induced intracellular calcium increase was also unaffected by CB or CD, but stimulus-induced eosinophil shape changes and translocation of PKCs and p47 phagocyte oxidase to the cell membrane region were completely inhibited by CB. PAF-induced eosinophil degranulation was inhibited by CB, CD, or anti-CD18 antibodies, whereas complement component 5-induced degranulation was not suppressed by CB. CONCLUSION: By itself, beta2 integrin-dependent cellular adhesion is not sufficient for promoting eosinophil effector function. Adequate actin assembly is required for eosinophil adhesion and also for full superoxide anion generation in eosinophils. 相似文献