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161.
162.
Hiroyasu Kitashiba Kumiko Taguchi Ikuyo Kaneko Kiyofumi Inaba Shuji Yokoi Yoshihito Takahata Takeshi Nishio 《Plant cell reports》2016,35(10):2197-2204
Key message
We identified three physical positions associated with embryo yield in microspore culture of Brassica rapa by segregation distortion analysis. We also confirmed their genetic effects on the embryo yield.Abstract
Isolated microspore culture is well utilized for the production of haploid or doubled-haploid plants in Brassica crops. Brassica rapa cv. ‘Ho Mei’ is one of the most excellent cultivars in embryo yield of microspore culture. To identify the loci associated with microspore embryogenesis, segregation analysis of 154 DNA markers anchored to B. rapa chromosomes (A01–A10) was performed using a population of microspore-derived embryos obtained from an F1 hybrid between ‘CR-Seiga’, a low yield cultivar in microspore-derived embryos, and ‘Ho Mei’. Three regions showing significant segregation distortion with increasing ‘Ho Mei’ alleles were detected on A05, A08 and A09, although these regions showed the expected Mendelian segregation ratio in an F2 population. The additive effect of alleles in these regions on embryo yield was confirmed in a BC3F1 population. One region on A08 containing Br071-5c had a higher effect than the other regions. Polymorphism of nucleotide sequences around the Br071-5c locus was investigated to find the gene possibly responsible for efficient embryogenesis from microspores.163.
164.
M Nakahama N Mohri S Mori G Shindo Y Yokoi R Machinami 《Virchows Archiv. B, Cell pathology including molecular pathology》1990,58(3):245-251
Age-related changes in medullary epithelial and dendritic cells in the human thymus were examined quantitatively using immunohistochemistry and histometry. The material used was thymic biopsy specimens obtained from 105 patients during cardiac surgery, none of whom had immunological abnormalities. By using keratin and tissue polypeptide antigen markers to identify epithelial cells and S-100 protein and LN-2 markers to identify dendritic cells, the numbers of these cells in the medulla were counted morphometrically. The relative proportions of the cortex, medulla, Hassall's bodies, perivascular space, connective tissue and fatty tissue were evaluated using a computer image-analysis system and the respective relative volumes were calculated. Our results indicate that the number of medullary dendritic cells/mm2 and the relative volume of cortical thymocytes decrease steadily up to the age of 40 years, whereas no major change was found in the number of medullary epithelial cells/mm2. 相似文献
165.
Takahide Kakuya Takashi Yamada Masayuki Yokokawa Tadakazu Ueda 《In vitro cellular & developmental biology. Plant》1983,19(8):591-599
Summary We have examined the conditions for cultivation of enzymatically dispersed cells from 34 human urothelial transitional cell
carcinomas (TCC) of various types. By employing two culture methods, stationary and tapping suspension, and by using the synthetic
medium DM 160 supplement with human umbilical cord serum and fetal bovine serum, six cell strains were established. In two
strains the tapping suspension culture method was suitable for growth of highly malignant cancer cells that detach easily
from the glass surface in stationary cultures. Each of the six cell strains has been maintained in culture for over 30 months
with repeated subcultures of 32 to 128 times. The histopathological features of the original TCC were three differentiated
papillary types and three anaplastic nonpapillary types. In two cell strains from TCC with low malignancy, however, the cancer
masses that formed in nude mice differed from the original TCC in which they became more malignant, and one cell strain resembled
the original TCC closely. In three stationary culture cell strains the epithelial nature was demonstrated by the presence
of desmosomes and tonofilaments. In one cell strain only tonofilaments were present. In two tapping suspension culture cell
strains the presence of desmosomes was not shown clearly, but fine tonofilaments were observed in one cell strain.
This work was supported in part by Grants 5319 and 5322 in aid for cancer research from the Ministry of Health and Welfare,
Japan. 相似文献
166.
H Takeuchi I Yokoi A Mori M Kohsaka 《Comptes rendus des séances de la Société de biologie et de ses filiales》1975,169(4):1099-1105
Effects of the following amino acids were examined on the electrical activity of the two giant neurones (PON and TAN) identified in the subesophageal ganglia of Achatina fulica Férussac : L-Asp, L-Thr, L-Ser, L-Glu, L-Pro, Gly, L-alpha-Ala, beta-Ala, L-cysteine, L-cystine, L-Val, L-Met, L-Ileu, L-Leu, L-Tyr, L-Phe, L-Lys, L-His, L-Arg, L-Cit, L-Try, GABA and GABOB. Among these substances, we observed an inhibitory effect of GABA and GABOB on the TAN excitability. GABA showed stronger effect on the TAN than GABOB. This effect of GABA was due to producing hyperpolarization on the TAN membrane. GABA showed a slight excitatory effect on the PON. The effect of GABOB on the PON was very weak and unstable. 相似文献
167.
delta-Guanidinovaleric acid (DGVA) was identified in human urine using thin layer chromatography (TLC), high performance liquid chromatography (HPLC) and gas chromatography/mass spectrometry (GC/MS). In the TLC, all Rfs of sample from urine developed by 6 solvent systems were identical to that of authentic DGVA. In the GC/MS, the mass spectrum of the sample was identical to the trifluoroacetylated dimethylpyrimidyl derivative of DGVA butylester (M+ = 375). In the HPLC analysis, the DGVA peak was observed just before 15 min in either chromatogram obtained by analysis of human urine or authentic DGVA, and the content of DGVA in pooled human urine was calculated at 2.4 nmol/ml. 相似文献
168.
Polygonal networks, "geodomes", in cultured hepatocytes of adult rats were examined by both light and electron microscopy. On light microscopical examinations of specimens stained with Coomassie blue after the treatment with Triton X-100, the networks were detected 5 days after culture, which consisted of triangles arranged mainly in hexagonal patterns. They surrounded main cell body, looking like a headband, or were occasionally situated over nuclei, looking like a geodesic dome. Scanning electron microscopical observations after Triton treatment revealed that these structures were located underneath surface membrane. Transmission electron microscopical investigations revealed that the connecting fibers of networks consisted of microfilaments which radiated in a compact bundle from electron-dense vertices. 相似文献
169.
Kenji Ida Yoichi Noda Juri Yano Aisaku Fukuda Hisashi Matsumoto Takahide Mori 《Primates; journal of primatology》1988,29(1):107-116
A total of 301 oocytes were recovered from crab-eating monkeys and subjected to insemination in vitro resulting in two fertilized
ova. Sixteen monkeys in 24 cycles received 37.5 IU of hMG daily from the second day of the menstrual cycle for 7 to 10 days.
Oocytes were recovered under laparotomy at 20 to 49 hr after administration of 1,000–1,500 IU of hCG. The maturation rate
of the recovered oocytes was 24.2% as judged from morphological criteria under the light microscope. With additional maturation
culture, the rate increased to 36.2%. The matured oocytes were inseminated at 3 to 4 hr after aspiration using homologous
spermatozoa which had been capacitated in vitro. Two oocytes were judged as being fertilized based on the presence of 3 and
5 pronuclei, respectively, when examined 12 hr after the insemination. This is the first report of in vitro fertilized ova
in nonhuman primates in Japan. 相似文献
170.
Hideaki Kabuto Isao Yokoi Kiminao Mizukawa Akitane Mori 《Neurochemical research》1989,14(11):1075-1080
3-((±)-2-Carboxypiperazin-4-yl)propyl-1-phosphonic acid (CPP) is an antagonist at the N-methyl-D-aspartate (NMDA) subtype of glutamate receptor. In the present study, levels of dihydroxyphenylacetic acid (DOPAC), homovanillic acid (HVA) and 5-hydroxyindolacetic acid (5-HIAA) were measured after intracerebroventricular injection of NMDA, CPP or both in rat striatum using a brain dialysis method. The injection of NMDA produced a significant increase in DOPAC level. HVA level was also increased by NMDA injection. The level of 5-HIAA was not affected by NMDA injection. The injection of CPP had no effect on DOPAC, HVA and 5-HIAA levels. The injection of CPP restrained the increase of DOPAC and HVA levels induced by NMDA injection. The results suggest that intracerebral injection of NMDA may increase dopamine release from rat striatum, but have no effect on serotonin release. Furthermore, CPP inhibits NMDA induced release of dopamine. 相似文献