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71.
Y. Kobayashi Yufuko Takahashi Satoshi Chikayama Motomi Ikeda Nobuhiko Uoshima Shinya Kimura Koji Tanaka Katuya Wada Masaru Ozawa Tatuo Sugano Naoyuki Maruo Motoharu Kondo 《Histochemistry and cell biology》1997,108(2):115-120
We devised a new microfluorometric method for determining the ploidy of megakaryocytes identified immunologically in bone
marrow smears. The smears were immunostained by incubation with mouse monoclonal anti-glycoproteins (GP) IIb antibodies, followed
by fluorescein isothiocyanate-conjugated goat anti-mouse IgG antibodies. They were then stained with 4′,6-diamidino-2-phenylindole
(DAPI). Megakaryocytes were identified by their GPIIb immunofluorescence using a microfluorometer and, after the filters were
changed, their DNA content was assayed by measuring the intensity of DAPI fluorescence. This intensity was shown to be proportional
to the DNA content when the aperture of the objective lens was reduced. We compared these results with those obtained when
megakaryocytes were identified morphologically, using DAPI staining after Wright-Giemsa destaining. In all 12 normal controls,
the ploidy peaks were shown to be 16N by both methods, and the mean ploidy detected by the immunological method was only reduced
0.961 times relative to the estimate from the morphological method. In contrast, in eight myelodysplastic syndrome (MDS) patients,
the ploidy peaks were either 8N or 4N and the mean was reduced by 0.906 times (P=0.018). Thus we could immunologically identify small megakaryocytes which we could not identify morphologically. Therefore,
this method is useful for measuring megakaryocytic ploidy, especially in the pathological megakaryocytes of MDS patients.
Accepted: 29 April 1997 相似文献
72.
Kimio Fukami Shinya Nishimura Masamichi Ogusa Miki Asada Toshitaka Nishijima 《Hydrobiologia》1997,358(1-3):245-249
A continuous culture system for a benthic food diatom Nitzschia sp. wasestablished by using properties of high nutrient and clean of deep seawater(DSW). DSW collected from 320 m depth in Muroto City, Japan, was introducedinto a glass-pipe bioreactor (14 cm length, 3 cm diam.) containing glassbeads of 0.5 cm diam. as substrata for the alga, and it was incubated at18°C · 80Em–2sec–1 · L:D=14:10. The chlorophyll a yield of benthicdiatoms in a reactor as a unit of surface area of the substratum was only0.001–0.003 g cm–2 when the flow rate of DSW was 0(batch culture conditions). However, when DSW was supplied continuously to areactor, the yield increased to 1.4 g-chl.a cm–2 alongwith the increase in flow rate of DSW. Moreover, amounts of chl.a washed outof the system were negligible, 0.0014 to 0.0045%, even though theflow rate of DSW was as much as 25 times h–1, suggesting thatsloughing of benthic diatoms from the substratum was minimized. Although theyield of diatoms fluctuated significantly at the time that the DSW wascollected, the variation could be minimized by increasing the flow rate ofDSW. These results indicate that the continuous culturing system with DSWsupports the stable and effective mass culture of benthic food diatom. 相似文献
73.
R Hashida S Kobayashi H Shirota K Yoshimatsu S Ohsawa H Hori S Hattori Y Nagai 《Prostaglandins》1984,27(5):697-709
Stimulation of synovial cell prostaglandin production by a factor obtained from casein-induced peritoneal polymorphonuclear (PMN) cells has been investigated. Both the extract and short time cultured medium of rat peritoneal PMN cells stimulate prostaglandin (PG)E2 production as well as collagenase production in the culture of rat synovial cells. PGE2 production by the cells in the presence of the PMN factor is much faster (5 to 24 hr) than collagenase production (24 hr or later, Biomedical Res. 3, 506-516, 1982). This stimulating factor is confirmed to be derived from PMN cells, based on the purification of the cells from peritoneal exudate cells by the Ficoll-Urographin method. Elution profile of the factor on gel filtration has indicated that both PGE2 and collagenase productions by synovial cells are stimulated by the same effluent fractions corresponding to molecular weights of 15,000 - 20,000 daltons and 30,000 - 40,000 daltons. These results suggest that PMN cells are involved in PG production as well as collagenase production in the inflamed tissue by stimulating connective tissue cells such as synovial cells. 相似文献
74.
Shinya Nomoto Michiaki Takasaki Hiroshi Naraoka Kaoru Harada 《Origins of life and evolution of the biosphere》1984,14(1-4):123-130
Flames of flammable gases, when blown against a surface of an aqueous solution of organic compounds, were found to induce oxidation as well as other reactions in the solution. This reaction would be regarded as a new model for formation of bioorganic molecules in the primitive hydrosphere exposed to some radical-containing atmosphere. 相似文献
75.
Takanobu Anai Jiro Yamamoto Ichiro Matsuda Naoki Taniguchi Takahito Kondo Bunsaku Nagai 《Human genetics》1984,66(2-3):282-285
Summary Two siblings with renal tubular acidosis (RTA) and nerve deafness were examined. It was found by ammonium chloride and bicarbonate loading tests that the 6-year-old brother had a hybrid type of RTA and his 4-year-old sister, a distal type of RTA. Enzyme activity and amount of enzyme protein of carbonic anhydrase isoenzyme I and II in red blood cells, measured using an immunoadsorbent method, were normal in both cases. Although this indicated that the RTAs of these patients are not generated by the carbonic anhydrase deficiency, an investigation with renal tissue is necessary to arrive at a final conclusion. 相似文献
76.
Chemical ionization (CI) mass spectra with isobutane and ammonia for the oligosaccharides obtained from sphingoglycolipids were compared with their electron impact (EI) mass spectra. The oligosaccahride moieties were liberated from the parent glycolipids and were further reduced with sodium borohydride. They were analyzed as their permethyl peracetyl and pertrimethylsilyl derivatives. In the CI spectra, peaks corresponding to QM+ and/or [M-59]+ were observed in all of the peracetylated oligosaccharides examined. In CI with ammonia as the reagent, H+ was transferred to nitrogen-containing saccharides to produce [MH]+ and NH4 was transferred to nitrogen-free saccharides to yield [M+NH4]+ as QM+. Non-reducing ends yielded very intense peaks in CI spectra. On the other hand, the reduced end, glucitol, produced rather prominent peaks in EI spectra. Fragment ions due to cleavage of glycosidic bonds were major ones under the CI conditions, and they could be used for elucidating the sugar sequence in the oligosaccharides. An additional characteristic feature in the CI spectra was that ions due to scission of hexosaminyl glycosidic linkages were observed with very high intensities. 相似文献
77.
Antennal responses of male European corn borer moths, Ostrinia nubilalis, to their two pheromone components, (Z)- and (E)-11-tetradecenyl acetates (tda), were studied. The electroantennogram (EAG) response was highest when the ventral side and lowest when the dorsal side of the antenna faced the air stream carrying the chemical stimulus. Repetitive stimulation with one of the isomers resulted in adaptation which affected the amplitude of response in subsequent tests of both (Z)- and (E)-11-tda. This suggested that the receptors for the two tda isomers are either identical or highly interactive. Mixtures of the two pheromone components did not elicit higher responses than the major component, (Z)-11-tda. A significant difference was observed between London and New York strains of this insect in their relative responses to (Z)- and (E)-11-tda. EAG responses of hybrids of these two strains resembled those for the New York strain. 相似文献
78.
79.
A seroepidemiological survey of varicella was made in the Nagoya area by the neutralization (NT) test. Of 1,473 recorded cases of varicella, 81.4% were under 6 years old and 9.6% were under one year old; of the 168 recorded cases under one year old, about 30% were under 5 months old. Examination of 11 pairs of mother and cord sera and 13 pairs of mother and infant sera showed that transfer of NT antibody was in general good, even in babies that were small for their age or smnall at birth after 28 weeks gestation. The transferred maternal antibody decreased rapidly, becoming undetectable in babies of 4 months old. Then with increase in age the percentgage of seropositive children gradually increased, being 53.3% at 4 to 5 years old, and 100% in those of over 9 years old, with a temporary decrease in young adults in their twenties. 相似文献
80.
Gerd N. La Mar Kiyoshi Nagai Thomas Jue David L. Budd K. Gersonde H. Sick T. Kagimoto A. Hayashi F. Taketa 《Biochemical and biophysical research communications》1980,96(3):1172-1177
The proton nmr spectra of the synthetic valency hybrids, α2(β+CN)2, (α+CN)2β2 of hemoglobin A and the natural valency hybrids of the mutant hemoglobins Boston, Iwate and Milwaukee have led to the unambiguous assignment of the two proximal histidyl imidazole exchangeable proton signals at 64 and 76 ppm to individual α and β subunits, respectively. New single non-exchangeable proton resonances detected in the extreme downfield region of the spectra of Hbs Boston and Iwate are tentatively assigned to the coordinated tyrosine of the mutated α chains. 相似文献