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981.
Ikuko Kondo Takeki Hirano Hideo Hamaguchi Yoshiaki Ohta Sachiko Haibara Hiroshi Nakai Hitoshi Takita 《Human genetics》1979,46(2):141-147
Summary An infant with karyotype 46,XY,der(8),t(3;8)(q21;p23) is presented. The presence of trisomy 3q21qter syndrome is suspected on the basis of comparison of the clinical and laboratory findings of this patient with those of cases that have been reported as partial 3q trisomy. The common phenotypic features of this syndrome include growth failure and mental or developmental retardation, hypotonia, persistent lanugo, distorted head, congenital glaucoma, short and upturned nose, prominent maxilla, micrognathia, short, webbed neck, short limbs, retroflexed third and fourth toes, cutaneous syndactyly of the second, third and fourth toes, and elevated galactose-1-phosphate uridyl transferase activity in the red blood cells. 相似文献
982.
Yoshiro Okano Mikiko Kataoka Takeshi Miyata Hiroshi Morimoto Kazuo Takahama Taizo Hitoshi Yoshitoshi Kasé Isamu Matsumoto Toshihiro Shinka 《Analytical biochemistry》1981,117(1):196-202
A method for the simultaneous analysis of pipecolic acid and proline in the brain is developed. The qualification and quantification of pipecolic acid and proline are accomplished with gas chromatography/mass spectrometry including a selected ion-monitoring technique by using deuterium-labeled proline as an internal standard, after the amino and carboxylic groups of these cyclic amino acids are derivatized with boron trifluoride methanol complex and heptafluorobutyric anhydride. The lower limit of quantification for the method is picomole levels and the concentration of pipecolic acid and proline in rat whole brain is determined to be 1.05 and 71.50 nmol/g of tissue, respectively. 相似文献
983.
Yoshiro Okano Takeshi Miyata Katsunori Iwasaki Kazuo Takahama Taizo Hitoshi Yoshitoshi Kasé Isamu Matsumoto Toshihiro Shinka 《Analytical biochemistry》1981,115(2):254-259
A specific and sensitive method for analysis of brain pyrrolidine, a volatile amine with potent synaptotropic actions on the peripheral and central nervous systems, was devised. The method involves the isolation of volatile amines by steam distillation and the qualification and quantification of pyrrolidine by gas chromatography/mass spectrometry () including a selected ion monitoring technique with deuterium-labeled pyrrolidine as an internal standard. The lower limit of quantification for the method was 2 pmol, and the mean concentration of pyrrolidine in the rat whole brain was determined to be 95 pmol/g of tissue. 相似文献
984.
The subcellular localization and biosynthetic site of 8-aminolevulinic acid dehydratase [EC 4.2.1.24
[EC]
, ALAD] were investigatedin relation to chloroplast development in radish cotyledons. ALAD was mainly located in the chloroplasts and cytoplasm. Mostof the ALAD in the chloroplasts was readily released by hypotonicshock. The enzyme was also found in the proplastids of etiolatedcotyledons. The normal increase in the activity of ALAD in the chloroplastsas well as the cytoplasm was inhibited by cycloheximide butunaffected by D-threo chloramphenicol and kanamycin during thegreening of radish cotyledons. We concluded that the ALAD inboth the cytoplasm and chloroplasts was synthesized on the cytoplasmic80S-ribosomes. This suggests that the ALAD formed on the 80S-ribosomesmight be incorporated into chloroplasts during their development. When etiolated radish seedlings were illuminated, ALAD in boththe cytoplasm and chloroplasts increased up to the point ofthe full development of the chloroplasts, and thereafter itdecreased. (Received August 20, 1975; ) 相似文献
985.
Hitoshi Wake Akinobu Akasaka Hironori Umetsu Yoshihiro Ozeki Koichiro Shimomura Tadashi Matsunaga 《Plant cell reports》1992,11(2):62-65
Summary Somatic embryos of Daucus carota L. developed into plantlets at high frequency after addition of an extract from a marine cyanobacterium, Synechococcus sp. NKBG 042902. High molecular weight, nondialyzing fraction, separated from the extract, possessed enhanced plantlet formation promoting activity. Plantlet formation frequency was 60 % after addition of nondialysate (100 mg/l) compared to 28 % without addition. Embryos treated with the nondialysate contained five times more chlorophyll than nontreated embryos after 6 days of culture. The chlorophyll a/b ratio of 4-day old treated somatic embryos was found to be similar to that of zygotic embryos. However, the chlorophyll a/b ratio of plantlets induced from nontreated somatic embryos was variable. Nondialysate was fractionated by ultracentrifugation and an active component obtained, which gave a maximum plantlet formation frequency of 71 %, and induced rapid greening of shoots.Abbreviations MS
Murashige and Skoog medium
- 2,4D
2,4-dichlorophenoxyacetic acid
- PCV
packed cell volume
- E
Einstein
- Chl
Chlorophyll
- vvm
volume of air, volume of medium per minute 相似文献
986.
Y F Sasaki H Yamada K Shimoi N Kinae I Tomita H Matsumura T Ohta Y Shirasu 《Mutation research》1992,269(1):79-95
The effects of post-treatment with heterocyclic amines and beta-carbolines on the induction of chromosome aberrations were studied in Chinese hamster CHO K-1 cells and SV40-transformed excision repair-deficient human XP2OSSV cells. The number of chromosome aberrations induced by UV and MMC were increased by post-treatment with Trp-P-1 and Trp-P-2, in both the presence and the absence of S9 mix. A alpha C, MeA alpha C, Glu-P-1, Glu-P-2, IQ, MeIQ, harman and harmine increased chromosome aberrations only in the presence of S9 mix. Glu-P-2, IQ, MeIQ, harman, and harmine did not induce chromosome aberrations by themselves at the concentrations used in this study. Trp-P-1, Trp-P-2, A alpha C, MeA alpha C and Glu-P-1 were weak clastogens by themselves, but at much higher concentrations than those at which they increased the induction of chromosome aberrations in cells pretreated with UV or MMC. Therefore, the increases in chromosome aberrations were not considered to be additive. 相似文献
987.
988.
989.
Hitoshi Suzuki Kimiyuki Tsuchiya Mitsuru Sakaizumi Shigeharu Wakana Osamu Gotoh Naruya Saitou Kazuo Moriwaki Susumu Sakurai 《Biochemical genetics》1990,28(3-4):137-149
Southern blot analysis of ribosomal DNA (rDNA) from seven species ofApodemus was carried out in order to examine the genetic relationships between the species. Analysis of heterogeneity in rDNA spacers inA. sylvaticus, A. flavicollis, A. semotus, A. agrarius, A. argenteus, A. speciosus, andA. peninsulae, using 13 different restriction enzymes and cloned mouse rDNA probes, revealed that the families of rDNA in these species can be characterized by restriction maps which show the major constituents of rDNA repeating units (repetypes). Based on differences in the arrangement of restriction sites, sequence divergence among the different major repetypes was estimated. Among the seven species ofApodemus examined, the major repetypes ofA. flavicollis andA. sylvaticus were the most closely related, having only 1.0% sequence divergence. These repetypes and those of the remaining five species differ substantially from one another, with 4.3–8.5% divergence.This study was supported in part by Grants-in-Aid for Scientific Research from the Ministry of Education, Science and Culture, Japan. 相似文献
990.
Hiroki Nakayama Xiao-Mei Ru Jun Fujita Tsutomu Kasugai Hitoshi Onoue Seiichi Hirota Hideya Kuroda Yukihiko Kitamura 《Development, growth & differentiation》1990,32(3):255-261
The dominant spotting (W) locus of the mouse has been demonstrated to be identical with the c-kit proto-oncogene. The c-kit is strongly expressed in hematopoietic organs and the brain of mice. In homozygotes and double heterozygotes of the W mutant alleles (hereafter W mutant), development of erythrocytes, mast cells, melanocytes and germ cells is deficient. The deficiency of erythrocytes, mast cells and melanocytes is attributed to a defect of precursor cells, but the cause of the germ cell deficiency is not clear. We investigated the effect of the W mutation on proliferative potential of cells composing various organs by examining aggregation chimeras between W mutant and wild-type (+/+) embryos. Proportions of +/+ components were significantly greater in the male germ cells and hematopoietic cells. In contrast, the average proportions of +/+ components were comparable to those of W mutant components in other organs including the brain. The present result suggests that the W (c-kit ) gene plays an important role in development of the male germ cells and hematopoietic cells and that it does not promote the proliferation of major cell population in the brain, in spite of the strong expression of the W (c-kit ) gene in the brain. 相似文献