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791.
OBJECTIVE: Pluripotent stem cells may be exist in the human amniotic membrane (HAM). The present article was aimed at establishing HAM cell lines and investigating their differentiation into osteoblasts in vitro. METHODS: HAM cell lines were established using routine cell culture techniques and expanded in vitro. RESULTS: HAM cells were propagated from 45 out of 50 specimens (90%) and all were maintained normal karyotypes in vitro. Alkaline phosphatase (ALP) activity and alizarin red S stain were positive for 12 out of 22 HAM cell lines (54.5%). The 22 HAM cell lines were selected at random. CONCLUSIONS: This study demonstrates that this isolation method II was more effective for establishing cell lines which differentiate into osteoblast rather than method I. 相似文献
792.
793.
794.
Isamu Akiba Hitoshi Endou Tsutomu Suzuki Saizo Yanaura Fuminori Sakai 《Life sciences》1981,29(10):1057-1063
Chronic administration of morphine caused a marked decrease in the urinary excretion of low molecular weight proteins (LMWP) including α2u-globulin (E.L. Stanley and O.W. Neuhaus, Biochim. Biophys. Acta, , 461–470, 1972), which exist only in male rats. Levels of urinary high molecular weight proteins, such as albumin and γ-globulin, however, were not significantly changed by morphine treatment. The amount of excreted LMWP was observed to decrease 3 days after giving morphine, 0.5 mg/g food, and to recover to the control level within 6 days after withdrawal of morphine. These findings suggest that the decrease of excreted LMWP may be related to the development of morphine dependence in male rats. 相似文献
795.
Burst-promoting activity in anemia and polycythemia 总被引:1,自引:0,他引:1
H Fukamachi A Urabe T Saito F Takaku M Kubota 《International journal of cell cloning》1986,4(2):74-81
Burst-promoting activity (BPA) in the sera of patients with various types of anemia and polycythemia was compared with that of normal subjects by an in vitro method using mouse bone marrow cells. The control culture contained normal human AB serum instead of sample materials. Results were expressed as a percentage of burst numbers in control cultures. Serum erythropoietin (Epo) levels were determined by a radioimmunoassay. Serum BPA in patients with aplastic anemia (155.4 +/- 56.7%, mean +/- SD) was significantly higher than that in normal subjects (112.1 +/- 29.1%, Wilcoxon's rank sum test, P less than 0.05). However, serum BPA in patients with uremic anemia (122.2 +/- 26.5%), polycythemia vera (101.9 +/- 19.5%) and stress polycythemia (115.5 +/- 25.6%) was not significantly different from normal subjects. There was a correlation between serum BPA and Epo titers in patients with aplastic anemia and paroxysmal nocturnal hemoglobinuria (r = 0.81, t test, P less than 0.001). 相似文献
796.
Isamu Murakoshi Kyoko Fukuchi Joju Haginiwa Shigeru Ohmiya Hirotaka Otomasu 《Phytochemistry》1977,16(9):1460-1461
A new lupin alkaloid, N-(3,-oxobutyl)cytisine, was isolated from the aerial parts of Echinosophora koreensis. Its structure was determined by s 相似文献
797.
A sensitive assay system of Yaba virus (YV) was established in a cynomolgus monkey kidney cell line, JINET, in which the virus caused multilayered cellular foci countable even with the unaided eye. The specificity of the foci induced by YV in these cells was demonstrated by (1) the focus-forming ability was destroyed by heating at 60 C for 12 min; (2) the focus formation was inhibited by specific antiserum; (3) specific fluorescence was detected only in cells composing the foci when tested by fluorescent antibody technique; (4) a linear relationship was observed between the virus concentration and the number of foci formed; (5) YV preparation passed 20 times in JINET cells still possessed “tumorigenicity” in cynomolgus monkeys. The sensitivity of JINET cells to YV was comparable to that of cynomolgus monkeys, and YV was successively propagated in JINET cells with 2 log increase in infectivity titer during over 40 serial passages. Application of this assay system to growth kinetic studies of YV and quantitation of neutralizing antibody to YV is also discussed. 相似文献
798.
An anchorage-dependent Wilms’ tumor cell line, HFWT, has been found to be extremely susceptible to human natural killer (NK) cells. Here we established a transfectant of HFWT with the green fluorescence protein (GFP) gene, designated GHINK-1 cells, to apply to the activated NK cytotoxicity assay without radioisotope labeling. After being co-cultured with CD3?CD56+ NK cells, GHINK-1 cells released GFP into the medium. The intensity of the fluorescence from the released GFP correlated almost exactly with the radioactivity of a standard 51Cr-release assay performed with suspension-cultured K562 cells. Because it does not require separation of the remaining live target cells by centrifugation, the non-radioisotopic GFP release assay with GHINK-1 cells is a convenient alternative for monitoring human activated NK killing activity. 相似文献
799.
Isamu Murakoshi Eiji Kidoguchi Mohammad Ikram Mohammad Israr Nusrat Shafi Joju Haginiwa Shigeru Ohmiya Hirotaka Otomasu 《Phytochemistry》1982,21(6):1313-1315
The major alkaloids of Sophora mollis are (+)-sparteine and (?)-cytisine, and the minor ones are also of the sparteine-type (lupanine and 5,6-deh 相似文献
800.
Isamu Murakoshi Eiji Kidoguchi Joju Haginiwa Shigeru Ohmiya Kimio Higashiyama Hirotaka Otomasu 《Phytochemistry》1982,21(9):2379-2384
Two new lupin alkaloids, isokuraramine and (?)-7, 11-dihydromatrine, were isolated from the fresh flowers of Sophora flavescens along with 16 kno 相似文献