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51.
Joji Sekine Kazuo Sano Masataka Uehara Tsugio Inokuchi 《Biotechnic & histochemistry》1996,71(3):152-156
A technique Is described for rapid detection of S-pha?e cells of tumor tissues in smear specimens using bromodeoxyuridine (BrdU) immunostaining. Mouse NR-S1 tumors and human tumor specimens were prepared for smear cytology after incubation in RPMI 1640 culture medium containing 200 μM BrdU at 37 °C under 3 atm for 1 hr. Samples were fixed in 70% ethanol for 30 min and used immediately or air dried for 30 min. Samples were then denatured in either 4 N HC1 or 0.07 N NaOH to prepare partially single-stranded DMA. Fixation with air drying for 30 min followed by 30 min in 70% ethanol and 1 min denaturation with 0.07 N NaOH resulted in satisfactory staining quality. Cultured tumor specimens were processed for routine paraffin sections after smears were made for cytology. The labeling indices of the smear specimens and of the paraffin sections gave similar results. This technique should be useful in evaluating the cell proliferative potential of tumor tissue in smear cytology without processing paraffin sections. 相似文献
52.
53.
Takashi Hirayarna Tatsuya Maeda Haruo Saito Kazuo Shinozaki 《Molecular & general genetics : MGG》1995,249(2):127-138
Yeast cells can respond and adapt to osmotic stress. In our attempt to clarify the molecular mechanisms of cellular responses to osmotic stress, we cloned seven cDNAs for hyperosmolarity-responsive (HOR) genes from Saccharomyces cerevisiae by a differential screening method. Structural analysis of the clones revealed that those designated HOR1, HORS, HOR4, HOR5 and HOR6 encoded glycerol-3-phosphate dehydrogenase (Gpd1p), glucokinase (Glklp), hexose transporter (Hxtlp), heat-shock protein 12 (Hsp12p) and Na+, K+, Li+-ATPase (Enalp), respectively. HOR2 and HOR7 corresponded to novel genes. Gpdlp is a key enzyme in the synthesis of glycerol, which is a major osmoprotectant in S. cerevisiae. Cloning of HOR1/GPD1 as a HOR gene indicates that the accumulation of glycerol in yeast cells under hyperosmotic stress is, at least in part, caused by an increase in the level of GPDH protein. We performed a series of Northern blot analyses using HOR cDNAs as probes and RNAs prepared from cells grown under various conditions and from various mutant cells. The results suggested that all the HOR genes are regulated by common signal transduction pathways. However, the fact that they exhibited certain distinct responses indicated that they might also be regulated by specific pathways in addition to the common pathways. Ca2+ seemed to be involved in the signaling systems. In addition, Hog1p, one of the MAP kinases in yeast, appeared to be involved in the regulation of expression of HOR genes, although its function seemed to be insufficient for the overall regulation of expression of these genes. 相似文献
54.
55.
The karyomorphology of 16 species in 13 genera representing Moraceae and Cecropiaceae was investigated in an effort to contribute
to a better understanding of chromosome features and evolution in the families. All genera investigated have similar karyomorphology,
but differences are found in (1) chromosome features of Interphase nucleus (simple, simple-complex, or complex chromocenter
type), (2) basic chromosome number (x=13 or 14), (3) size variation (mono-or bimodial), and (4) frequencies of chromosomes with median centromeres (m-chromosome) (25–85%) and those with subterminal (or terminal) centromeres (st-chromosome) (14–69%). Comparisons with Ulmaceae as an outgroup of the remainder of Urticales suggest that the simple chromocenter
type,x=14 comprising bothm- andst-chromosomes, and the monomodial karyotype are plesiomorphies in Moraceae and Cecropiaceae. Most of Moraceae and Cecropiaceae
retain generalized chromosome features of the order, but have involved a few evolutionary changes in karyomorphology. Based
on some detailed karyomorphological data, inter- and infrafamilial relationships are also briefly discussed. 相似文献
56.
Peter J. Robinson Michael Steinmetz Kazuo Moriwaki Kirsten Fischer Lindahl 《Immunogenetics》1984,20(6):655-665
To determine the distribution of beta-2 microglobulin (B2m) alleles in wild mice we have typed mice derived from natural populations in Europe, North Africa, South America, and East Asia. Mus musculus domesticus mice from Germany, France, Italy, and Peru were all B2m
a
as were most from the United Kingdom. M.m. musculus mice from Denmark and Czechoslovakia, several stocks of M.m. molossinus from Japan, and M.m. castaneus from China, Thailand, and the Philippines were of B2m
b
type. This is consistent with the notion that C57BL/6 may have obtained some of its genes, including B2m, from Eastern mice. A BgII restriction site characteristic of B2m
b
was also found in mice from Czechoslovakia and Japan, confirming that B2m
b
is a naturally occurring allele of B2m. A new type of
2m (
2mw1) was found in four stocks of M. spretus from Portugal, Spain, and Morocco. This molecule differs in apparent size and charge from the a and b types.
2mw2 was found together with
2 ma in one stock of M.m. domesticus (brevirostris) from Morocco.
2mw3 and
2mw4 were found in a few M. m. bactrianus from Pakistan. In all cases tested, these new
2m molecules associate with class I histocompatibility antigens.Abbreviations used in this paper
2m
beta-2 microglobulin
-
B2m
gene for beta-2 microglobulin
- IEF
isoelectric focusing
- SDS-PAGE
polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulfate
- MHC
major histocompatibility complex
- T. E.
Tris-EDTA buffer 相似文献
57.
Kazuo Okamura Kazuyasu Kisaichi Ken-ichiro Takamiya Mitsuo Nishimura 《Archives of microbiology》1984,139(2-3):143-146
A soluble cytochrome, cytochrome c-551 was purified from an aerobic photosynthetic bacterium Erythrobacter species strain OCh 114 (ATCC No. 33942) by ammonium sulfate fractionation, ion-exchange chromatography and gel-filtration. The cytochrome had absorption maxima at 277, 410, and 524–525 nm in the oxidized form, and at 415, 522, and 550.5 nm in the reduced form. At 77 K, the -band of the absorption spectrum of the reduced form split in two at 547 and 549 nm. The millimolar absorption coefficient at 550.5 nm was 26.8 mM-1 cm-1 in the reduced form. This cytochrome was an acidic protein with an isoelectric point of 4.9. Its molecular weight was determined to be 15,000 by gel-filtration on Sephadex G-100 and 14,500 by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The midpoint potential of this cytochrome was +250 mV at pH 7.0. This cytochrome did not bind CO. 相似文献
58.
The extraordinary sensitivity of early erythroid progenitor cells (BFU-e) of normal human bone marrow to tritiated thymidine ([3H]TdR) was studied. While exposure of bone-marrow cells to [3H]TdR for 1 hr resulted in the death of only 40% of the granulocyte-macrophage progenitor cells (CFU-c), 90% of BFU-e were killed. Experiments in which normal bone-marrow cells were mixed with bone-marrow cells which had been exposed to [3H]TdR demonstrated that the excessive killing of BFU-e by [3H]TdR reflected carry-over of the [3H]TdR by the exposed cells. A carry-over effect was not observed for CFU-c, suggesting the presence of a fundamental difference in the metabolism of TdR between CFU-c and BFU-e. There was a suggestion of a carry-over effect regarding two other S-phase-specific agents, hydroxyurea and 1-β-D-arabinofuranosylcytosine. 相似文献
59.
Kazuo Suzuki 《Journal of plant research》1984,97(3):381-396
Observations on native populations of JapaneseEpimedium have revealed that two types of effective pollinators can be recognized. One of the two types, which consists of small bees
(mainlyAndrena spp. andLasioglossum spp.), is characterized by nondiscriminating behavior for collecting pollen and is commonly found inEpimedium. The other type, which comprises medium sizedTetralonia nipponensis and largerBombus diversus queens as main components, showed flower-dependent foraging fidelity associated with nectar-sucking behavior.T. nipponensis with a shorter proboscis pollinated flowers with a shorter spur ofE. trifoliatobinatum and of a part ofE. s sempervirens, while the queen ofB. diversus with a longer proboscis pollinated longer spurred flowers ofE. grandiflorum andE. sempervirens. In the populations of putative hybrid-derivatives which show gradational variations of spur length, bees of the pollencollecting
type pollinated any flower non-discriminately while bees of the nectar-foraging type tended to visit the flowers with spur
lengths corresponding to their proboscis length. These observations suggest that the pollen-collecting bees play an important
role for gene flow among theEpimedium species, and the nectar-foraging bees reinforce the isolation between the species by their selective pollination. Reproductive
isolation between species ofEpimedium is discussed in relation with some practical behavior, such as flying power, of the pollinators. 相似文献
60.
Journal of Plant Research - The arrangement of microfibrils in the wall of epidermal cells in the epicotyl of the azuki bean plant has been observed. The outer and inner tangential walls have a... 相似文献