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71.
Eiitsu Nakajima Hideo Orimo Miyoko Ikejima Takashi Shimada 《Journal of human genetics》1995,40(4):343-345
Summary We have identified a polymorphic 9-bp repeat sequence in exon 1 of thehMSH3 gene using polymerase chain reaction (PCR). Five alleles were observed in unrelated Japanese individuals with heterozygosity of 0.57. 相似文献
72.
Dipole-tracing of 'awareness' attenuating the cortical components of somatosensory evoked potentials 总被引:1,自引:0,他引:1
Using the dipole-tracing method, the source generators of N18, P22 and P40 of the somatosensory evoked potential (SEP) were estimated as the equivalent dipole. After voluntary action of the thumb flexion, no changes were observed in N18 or P40, but the amplitude of P22 was suppressed. The after-effects of intention accompanied by a voluntary action or the subject's awareness that electrical stimulation will be given after the voluntary action were treated as 'awareness'. By subtracting the pure SEP from SEP during 'awareness', it was found that the equivalent dipole of 'awareness' of P22 was located at the same region of pure P22, but the vector was of opposite orientation. 'Awareness' attenuated the perceptive potential of SEP like P22 generated in the cortex. 相似文献
73.
Yoko Kamitani Eiji Kajii Toshio Suda Shigenori Ikemoto 《Journal of human genetics》1992,37(4):271-283
Summary In order to examine expression of the Tn antigen on erythroid cells from a patient with Tn syndrome, we applied a selective two phase liquid culture system for human erythroid progenitors in peripheral blood. The cells were analyzed with flow cytometry employing an anti-Tn antibody and a lectin ofVicia villosa which recognizes only the Tn determinant. In the second phase, the Tn antigen was expressed on the cultured cells from the patient on day 3 and Tn-positive cells reached 62.7% on day 9. On the other hand, Tn-positive cells were not detected in the volunteer's cultured cells. When the patient's cells were co-cultured with the cells from a healthy voluteer, the percentage of Tn-positive cells was much lower than the expected value, suggesting that the normal cells suppressed the expression of Tn antigen on the patient's cells. 相似文献
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77.
Speed of repolarization and morphology of glygerol-treated frog muscle fibres 总被引:6,自引:0,他引:6 下载免费PDF全文
1. Single muscle fibres from frog semitendinosus were subjected to sudden changes in [K](o), while recording membrane potential.2. In agreement with Hodgkin & Horowicz (1960), a sudden increase in [K](o) in normal fibres produced a rapid depolarization (half-time 0.3 sec), whereas a sudden decrease in [K](o) produced a slower repolarization (half-time 2-3 sec).3. Fibres were subjected to ;glycerol-treatment', a procedure which was supposed to produce a functional disconnexion of the T-system from the surface. In these glycerol-treated fibres both depolarization and repolarization induced by changes of [K](o) took place rapidly.4. The results suggest that the slowness of the repolarization in normal fibres is due to a retention of K ions inside the T-tubules.5. Electron microscopical observation of single fibres or bundles of fibres, which have been soaked in a Ringer containing ferritin, revealed that normal fibres contained ferritin particles in the T-system, while glycerol-treated fibres showed no ferritin. Except for the presence of some large vacuoles and some swelling of the T-system, glycerol-treated fibres appeared morphologically normal.6. Prolonged soaking in a high potassium solution produced electrical effects suggesting that K ions can enter the tubules of treated fibres very slowly, in spite of their inaccessibility to ferritin.7. The main effect of glycerol-treatment does not seem to be a total disconnexion of the T-system from the fibre surface, but rather constriction of the T-tubules near their openings to the exterior. 相似文献
78.
Takeshi Ogawa Hiromi Matsuzaki Hiroshi Uei Shinya Nakajima Yasuaki Tokuhashi Mariko Esumi 《Pathobiology》2005,72(3):146-151
OBJECTIVE: We constructed a passive cigarette-smoking model with rats to investigate the molecular mechanism of intervertebral disc degeneration, and found by gene expression analysis that passive cigarette smoking stimulated the stress-responsive signal pathway and inhibited the apoptotic pathway. In this study, to clarify that these changes were derived from either nucleus pulposus (NP) or annulus fibrosus (AF), we separately collected NP and AF and quantitatively analyzed gene expression. METHODS: Total RNA was extracted from NP and AF of the lumbar intervertebral discs from rats which were kept in a smoking box for 4 and 8 weeks. Gene expression was measured by real-time PCR of cDNA synthesized from the total RNA. RESULTS: Stress-responsive protein, heat shock protein 70, was expressed similarly in NP and AF, and was upregulated to the same degree after 8 weeks of passive cigarette smoking. The protein tyrosine phosphatase gene was expressed more strongly in AF than in NP, and was upregulated after 8 weeks of smoking in both tissue parts. The type II collagen and aggrecan genes were predominantly expressed in AF and NP, respectively. CONCLUSION: These results indicate that passive cigarette smoking stimulates both NP and AF, and induces the stress-responsible genes such as heat shock protein 70 and protein tyrosine phosphatase in both. 相似文献
79.
Nomura H Nishimori H Yasoshima T Hata F Tanaka H Nakajima F Honma T Araya J Kamiguchi K Isomura H Sato N Denno R Hirata K 《Clinical & experimental metastasis》2002,19(5):391-399
To elucidate the mechanisms of metastasis, we established two sublines HPC-1H5 with a highly liver metastatic cell line and
HPC-1P5a with a highly peritoneal disseminating cell line, which were sequentially selected from the parental pancreatic cancer
cell line HPC-1. Using these three cell lines, we investigated several biological properties and mRNA levels of differentially-expressed
genes involved in cancer metastasis by cDNA macroarray. Microscopic findings for the three cell lines were the same. The tumorigenicity,
in vitro growth ability, motile activity, adhesive activity and the production of IL-8 of metastatic sublines were higher than those
of parental HPC-1 cells. Particularly, HPC-1H5 cells showed clearly higher levels of IL-8 expression and tumors of HPC-1H5
cells grew faster and bigger than those of HPC-1P5a cells. In cDNA macroarray analysis of HPC-1H5 cells, 22 genes were up-regulated
and 44 genes were down-regulated compared with parental HPC-1 cells. In HPC-1P5a cells, 9 genes were up-regulated and 28 genes
were down-regulated compared with parental HPC-1 cells. This study provides a demonstration of global gene expression analysis
of pancreatic cancer cells with liver metastasis and peritoneal dissemination. Furthermore, our results provide a new insight
into the study of liver metastasis and peritoneal dissemination of human pancreatic cancer.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
80.