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1.
Replication of X chromosomes in complete moles 总被引:1,自引:0,他引:1
Summary DNA replication patterns of X chromosomes in complete hydatidiform moles were studied using cultured fibroblasts from three 46,XX moles resulting from duplication of a haploid sperm, and from a 46,XY mole originating from dispermy. Control cultures included skin fibroblasts from an adult woman and a female fetus as well as PB lymphocytes from an adult woman. Cultures were treated with 5-bromodeoxyuridine for the last 2–4h of the S phase, and the chromosome slides prepared were stained by the Hoechst 33258-Giemsa procedure. Each of the three XX moles studied revealed one early-replicating and one late-replicating X chromosomes, while the XY mole revealed one early-replicating X chromosome. DNA replication patterns of molar X chromosomes were similar to those of adult and fetal fibroblasts, but different from those in adult lymphocytes. These findings indicate that DNA replication kinetics of molar fibroblasts are tissue-specific rather than origin- or developmental-stage specific. 相似文献
2.
Norio Masui Yumie Takagi Tetsu Nishikawa Makoto Yanabe Masato Nose Katsunori Sato 《Experimental Animals》2002,51(5):501-503
A new polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis was developed for genetic typing of the mouse Tnfsf6gld mutation. An artificial restriction site was introduced to the mouse Tnfsf6gld mutation by PCR amplification using a modified primer. The three genotypes of the Tnfsf6 locus (Tnfsf6gld/Tnfsf6gld, Tnfsf6gld/+, and +Tnfsf6-gld/+Tnfsf6-gld) could be distinguished clearly and easily. This PCR-RFLP analysis was found to be useful for the identification of the mouse Tnfsf6gld mutation. 相似文献
3.
Katayama Masato; Thiruvikraman Singanallore V.; Marumo Shingo 《Plant & cell physiology》1987,28(2):383-386
The natural chlorinated auxins 4-chloroindole-3-acetic acid(4-Cl-IAA) and its methyl ester (4-Cl-IAA Me ester) were found,in addition to IAA and its Me ester, by gas chromatography-massspectrometry in immature seeds of Vicia amurensis, a Vicieaespecies. In contrast, only non-chlorinated, IAA and IAA Me esterwere present in immature seeds of three Phaseoleae species.These results are further evidence of the wide distributionof 4-Cl-IAA and its Me ester in various Vicieae. (Received October 3, 1986; Accepted December 22, 1986) 相似文献
4.
Yutaka Nagata Masato Ando Mitsuyoshi Iwata Atsushi Hara Tamotsu Taketomi 《Journal of neurochemistry》1987,49(1):201-207
The effects of some gangliosides on active uptake of nonmetabolizable alpha-aminoisobutyric acid (AIB) and Na+, K+-ATPase and Ca2+, Mg2+-ATPase activities in superior cervical ganglia (SCG) and nodose ganglia (NG) excised from adult rats were examined during aerobic incubation at 37 degrees C for 2 h. In NG, amino acid uptake was greatly accelerated with the addition of galactosyl-N-acetylgalactosaminyl-[N-acetylneuraminyl]-galactosylgluc osyl ceramide (GM1) (85%) and also with N-acetylgalactosaminyl-[N-acetylneuraminyl]-galactosylglucosyl ceramide (GM2) or [N-acetylneuraminyl]-galactosyl-N-acetylgalactosaminyl-[N-acetyl- neuraminyl]-galactosylglucosyl ceramide (GD1a) (43% each) compared with a nonaddition control at a 5 nM concentration. Under identical conditions, Na+, K+-ATPase activity was strongly stimulated with GM1 (180%) and GD1a (93%), whereas Ca2+, Mg2+-ATPase activity showed no change. In SCG, on the other hand, AIB uptake was apparently inhibited (-27%) by addition of GM1, with a slight decrease in Na+, K+-ATPase but no change in Ca2+, Mg2+-ATPase activity in the tissue. Both asialo-GM1, in which N-acetylneuraminic acid is deficient, and Forssman glycolipid, which is not present in nervous tissue, failed to produce any significant increase in both SCG and NG not only in amino acid uptake, but also in Na+, K+-ATPase activity. A kinetic study of active AIB uptake showed that GM1 ganglioside produced an increase in Km with no change in Vmax in SCG, whereas it caused a decrease in Km with a slight increase in Vmax in NG. Treatment of NG and SCG with neuraminidase from Vibrio cholerae, an enzyme that split off sialic acid from polysialoganglioside, leaving GM1 intact, caused little inhibition of the amino acid uptake.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Katsuya Koike Masato Mori Yukishige Ito Yoshiaki Nakahara Tomoya Ogawa 《Glycoconjugate journal》1987,4(2):109-116
The first total synthesis of glycosphingolipids isolated from wheat flour has been achieved in a regio- and stereo-controlled manner.Abbreviations THF
tetrahydrofuran
- DMF
dimethylformamide
Part 53 in the series Synthetic Studies on Cell Surface Glycans 相似文献
6.
Liver glutathione S-transferase polymorphism in Japanese and its pharmacogenetic importance 总被引:1,自引:1,他引:0
Shoji Harada Masato Abei Naomi Tanaka Dharam P. Agarwal H. Werner Goedde 《Human genetics》1987,75(4):322-325
Summary A total of 168 autopsy liver extracts from Japanese individuals were examined for the glutathione S-transferase (GST) isozymes by means of starch gel electrophoresis. The gene frequencies of GST1*1, GST1*2, and GST1*0 in Japanese were 0.252, 0.057, and 0.691, respectively. GST1*3 was detected as a rare variant allele. The incidence of GST1 0 in 41 liver biopsy samples from patients suffering from various liver diseases was investigated using polyacrylamide gel isoelectric focusing. The GST1 0 phenotype was found more frequently in livers with hepatitis and carcinoma than in control livers. The isozymes coded by different GST loci were partially purified and characterized to study their biochemical properties. The apparent Km values with 1-chloro-2,4-dinitrobenzene (CDNB) as substrate for the isozymes at the GST1, GST2, GST3, and GST4 loci were 604, 1345, 776 and 591 M, respectively. 相似文献
7.
Takeshi Tsunetoshi Atsuhiro Otsuka Hiroshi Mikami Katsuhiko Kohara Katsutoshi Katahira Toshio Ogihara 《European journal of applied physiology and occupational physiology》1989,58(7):705-709
We have previously demonstrated that blood pressure elevation by acute blood volume expansion is volume-dependent during the infusion period and resistance-dependent in the post-infusion period in normal anesthetized dogs, and that such an increase in blood pressure is associated with a potentiation of the pressor response to norepinephrine. To evaluate the possible renal contribution to these hemodynamic changes, blood volume expansion was performed for 1 h with dextran dissolved in lactated Ringer's solution (20 ml/kg) in 15 nephrectomized dogs. The mean blood pressure, cardiac output and total peripheral resistance at the end of infusion were 126%, 225% and 60%, respectively; 3 h after volume expansion they were 126%, 151%, and 92% respectively. However, in 4 dogs, there was an increase in mean blood pressure (138%) 3 h after volume expansion. This was thought to result from an increase in the total peripheral resistance (133%) associated with the recovery of cardiac output (106%). The pressor response to norepinephrine (0.5 microgram/kg) was potentiated after volume expansion. These results indicate that the handling of volume by the kidney contributed to the maintenance of an elevated level of cardiac output. However, nephrectomy did not seem to interfere with the hemodynamic switching of the causative factor for blood pressure elevation from increased cardiac output to increased total peripheral resistance. Neither was the potentiation of pressor response to norepinephrine affected. 相似文献
8.
One- and two-dimensional NMR studies on the conformation of DNA containing the oligo(dA)oligo(dT) tract. 总被引:8,自引:6,他引:2
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M Katahira H Sugeta Y Kyogoku S Fujii R Fujisawa K Tomita 《Nucleic acids research》1988,16(17):8619-8632
The resonances of the imino protons and all of the non-exchangeable protons (except for H5'/H5') of d(CGCAAAAAAGCG)d(CGCTTTTTTGCG) have been assigned by means of one- and two-dimensional NMR spectroscopies. Qualitative analyses showed that the overall structure is of the B-form, but local conformational deviations exist. The NOEs between the imino protons of thymines and H2 of adenines suggest that the A-T base pairs are propeller-twisted to almost the same degree as in crystals. A remarkable chemical shift of H1' was observed for the residue located just before the oligo(dA)oligo(dT) tract, suggesting the presence of conformational discontinuity at the junctions between the oligo(dA)oligo(dT) tract and the other portions. Analyses of cross peaks in NOESY spectra between H2 of adenines and H1' of the 3'-neighbouring residues on the complementary strand revealed that the minor groove of the oligo(dA)oligo(dT) tract is narrow and compressed gradually, from 5' to 3', along the tract. 相似文献
9.
Masato Tsukahara Hiroshi Shinkai Chidori Asagami Tsuyako Eguchi Tadashi Kajii 《Human genetics》1988,78(1):9-12
Summary A mother and daughter are described with light and electron microscopic, and biochemical abnormalities of their connective tissue characteristic of both cutis laxa and the Ehlers-Danlos syndrome. The mother was clinically normal, while her 8-year-old daughter exhibited loose, wrinkled skin and other clinical features of cutis laxa, and also fragility, bruisability and hyper-extensibility of the skin and poor healing of wounds, leaving cigarette paper scars, features characteristic of the Ehlers-Danlos syndrome. Light and electron microscopic studies of skin biopsy specimens and cultured skin fibroblasts from both individuals revealed reduced and distorted elastic fibres, a finding usually seen in cutis laxa. Electrophoretic studies of collagen excreted from cultured skin fibrobasts revealed in both individuals and alpha 2(I) chain with a molecular size smaller than usual. The father and elder daughter were normal by clinical, light and electron microscopic and electrophoretic studies. It was concluded from these findings that the mother and daughter represented a hitherto undescrbed disease of the connective tissue with dominant inheritance and variable expressivity. 相似文献
10.
Shinichi Ikemoto Seiji Wada Masato Kamizuru Nobuyuki Hayahara Taketoshi Kishimoto Masanobu Maekawa 《Cancer immunology, immunotherapy : CII》1992,34(5):289-293
Summary The authors examined interleukin-2 (IL-2) production and interferon (IFN) production of peripheral blood mononuclear cells in 28 patients with renal cell carcinoma and 17 control subjects. The peripheral blood was obtained prior to the initiation of therapeutic procedures. The patients were divided into two groups according to tumor size, 5 cm and >5 cm. The production of IL-2 and IFN was measured by immunoradiometric assay. As a result, in the patients with tumors >5 cm, IL-2 and IFN production was impaired. However, in the patients with tumors 5 cm, IFN production was enhanced, though IL-2 production was not significantly different from that of the control subjects. There was no significant correlation between IL-2 production and IFN production. 相似文献