20 research outputs found

    Genetic relationship between the Hiroshima and Ryoke granites as indicated by some geochemical evidence

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    Some new data on granophyres (the Namariyama quarts-diorites) in the Ningyo-toge area

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    A new occurrence of granophyric body was described and its geological significance was discussed with regard to classification of Late Cretaceous to Early Tertiary plutonic activities in the area

    Oxygen Isotopic Data and Description of Rocks of the Yanai District in the Ryoke Belt, Japan

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    Ammonium content of Archean rocks of the Superior Province

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    Ammonium contents were determined for clastic sediments and associated volcanic rocks of the Kirkland Lake area, Abitibi greenstone- granite belt and metamorphic, migmatitic and granitic rocks of the Ear Falls-Dryden area, English River gneiss-granite belt. The NH(4) centents of Archean volcanic rocks (2700~2710m.y.) are very low (0~6 ppm) and immature argillites have also low contents of NH(4) (27~43ppm). On the other hand, a black shale from the Timiskaming Group (2100m.y.) are rich in graphite and pyrite and contain much NH4 (130ppm), providing a firm evidence of relatively abundant presence of an Archean biota compared with a sparcity of morphological record of Archean fossils. The NH(4) content of the rock mentioned above is about a third of those of the upper Proterozoic sediments and it remains to be established whether it reflects the abrupt break in the evolution of life near the Archean-Proterozoic boundary or not. A considerable amount of NH(4) is inherited by highly metamorphic pelitic gneisses and there may be a possibility for indirect prospection of early life by a study of NH(4) in highly metamorphic rocks of the early Archean. It was also found that the gneissic granitoid has much higher content of NH(4) than the post· kinematic massive granitoid

    On diabese-gabbro dykes in the Ogamo and Kurami granites

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    Two diabase-gabbro dykes intruding into the Ogamo and Kurami grani tes were descibed and their relationships to other Late Cretaceous to Early Tertiary intrusive rocks were discussed

    Isotopic Analysis of Rb and Sr Using a Full Automatic Thermal Ionization Mass Spectrometer

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    Analytical method for strontium isotope ratios and rubidium and strontium concentrations has been established using a full automatic thermal ionization mass spectrometer. The machine is a modified model "MAT 260" of Varian MAT LTD. Each of simultaneously loaded thirteen samples is successively analysed full automatically following to a specific controling program which has been selected as being most suitable for each sample. However, the most characteristic feature of this machine compared to other types is computer controled peak jumping and peak centering before measurment of the signal of each peak. By this the accuracy of isotopic measurement has been surprisingly improved. Analytical procedures are described in detail which include decomposition of samples, separation of Rb and Sr, loading samples on filament and mass spectrometry. Accuracy and reproducibility of isotope analyses are excellent : 43 separate analyses of standard sample NBS 987 over one year gave a mean (87)Sr/(86)Sr ratio of 0.710238 (normalized to the (88)Sr/(86)Sr ratio of 8.375209) with a value of 20δ of 0.000008. The ratio obtained is slightly higher than the value of 0.71014 given by NBS, but it is almost identical to the mean of recently reported twenty analyses. Our determinations for Rb and Sr concentrations of standard samples are as follows : JG-1, Rb 184.4 ppm, Sr 185.5 ppm; JB-l, Rb 41.5Ppm, Sr 448.4 ppm , each of which is near the mean of reported values for corresponding element of the sample (ANDO et al., 1974). Concentrations of Rb and Sr in pure water and regents used in chemical treatement of samples were also measured; a possible error due to the contamination is negligible for most geochemical samples

    High testosterone levels in prostate tissue obtained by needle biopsy correlate with poor-prognosis factors in prostate cancer patients

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    Background: There is currently no consensus on the correlations between androgen concentrations in prostate tissue and blood and stage and pathological grade of prostate cancer. In this study, we used a newly-developed ultra-sensitive liquid-chromatography tandem mass spectrometry method to measure testosterone (T) and dihydrotestosterone (DHT) concentrations in blood and needle biopsy prostate specimens from patients with prostate cancer.Methods: We analyzed androgen levels in 196 men diagnosed with prostate cancer. All patients had undergone systematic needle biopsy, and an additional needle biopsy from the peripheral zone was conducted for the simultaneous determination of T and DHT. We analyzed the relationships between T and DHT levels in tissue and blood and Gleason score, clinical stage, and percentage of positive biopsy cores, using multivariate analysis. Results: The median T and DHT levels in blood were 3551.0 pg/mL and 330.5 pg/mL, respectively. There was a strong correlation between serum T and DHT. The median T and DHT levels in prostate tissue were 0.5667 pg/mg and 7.0625 pg/mg, respectively. In multivariate analysis, serum prostate-specific antigen and tissue T levels were significantly associated with poor prognosis; high T levels in prostate tissue were significantly related to high Gleason score (p = 0.041), advanced clinical stage (p = 0.002), and a high percentage of positive biopsy cores (p = 0.001). Conclusions: The results of this study indicate that high T levels in prostate tissue are related to high Gleason score, advanced clinical stage, and a high percentage of positive biopsy cores in patients with prostate cancer. T level in needle biopsy specimens may therefore be a useful prognostic factor in prostate cancer patients

    Oxygen Isotopic Data and Description of Rocks of the Yanai District in the Ryoke Belt, Japan

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    A preliminary study of Rb-Sr systematics and trace element abundances on impact-melted LL-chondrites from Antarctica

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    Rb-Sr systematics, REE, Ba, Sr, Rb, K, Ca and Mg abundances were analyzed in 1) whole-rock samples from 8 Antarctic LL-chondrites including 4 impact-melted rocks and 2 non-Antarctic LL chondrites, and 2) 8 mineral separates from one of the impact-melted meteorites, Y-790964. In a ^(Rb)-^(Sr) evolution diagram, analyses from the severely shocked meteorites deviate from the 4.5 b. y.-evolution line although those of normal LL-chondrites are plotted on or close to the line, suggesting a late thermal evolution of these impact-melted meteorites. Analyses of mineral separates and a whole-rock from Y-790964 yield a Rb-Sr internal isochron age of 1197±54 (2σ) m. y. and an initial ^(Sr)/^(Sr) ratio of 0.73160±0.00028 (2σ). This age is the youngest known among impact-related materials in brecciated meteorites. In addition, the impact-melted meteorites have somewhat higher and fractionated REE, Sr, Rb and K abundances compared with normal LL chondrites. The 1.2 b. y. age is interpreted as a time of melting induced by intense impacts on the LL-chondrite parent body, accompanied by REE, Rb/Sr and K fractionations. Therefore, we suggest that strong impact and regolith processes on the LL-chondrite parent body never ceased until at least 1.2 b. y. ago
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