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941.
Extracts from the cotyledons of seedlings of Pharbitis nil strain‘Violet’ cultured at low temperature, which inducestheir flowering even in continuous light, with or without precedentexposure to high-intensity light, which shortens the periodof low temperature required for flowering, were analyzed byHPLC for substances correlating with the flower-inducing process.The content of two phenylpropanoids were found to increase duringthe low-temperature, and were identified as 3-O-feruloylquinicacid and dehydrodiconiferyl alcohol-13-O-ß-D-glucoside.The increase was more rapid in the cotyledons exposed to high-intensitylight before the low-temperature. This suggests that the accumulationof these compounds is correlated to the promotive effect ofhigh-intensity light on the flower-induction by low temperature. (Received March 7, 1994; Accepted April 2, 1994)  相似文献   
942.
943.
After E. coli cells (WP2 and WP2uvrA) were treated with chemical mutagens (methyl methanesulfonate, MMS; N-methyl-N-nitrosourea, MNU; 4-nitroquinoline 1-oxide, 4NQO) in 1/15 M phosphate buffer, the mutability of the treated cells plated on a D2O-agar plate was compared with that plated on an ordinary H2O-agar plate. The mutation frequency decreased more or less on the D2O-agar plate. The D2O-substitution effects, as termed by the relative mutation frequencies (MFD2O/MFH2O), are 0.92 for MMS, 0.29 for MNU, and 0.42 for 4NQO in WP2, and 0.68 for MMS, 0.49 for MNU, and 0.16 for 4NQO in WP2uvrA. The D2O effect seemed to be partly related to the function of the uvrA gene-associated products. The pH dependence of mutability was discussed in connection with the D2O-substitution effect.  相似文献   
944.
The mountain zone of Yakushima Island is covered with a mixed conifer-broadleaved forest dominated by old-growth Cryptomeria japonica (L.f.) D. Don trees. Even though Yakushima Island has been frequently struck by typhoons with wind velocities exceeding 55 m s−1, the Cr. japonica trees in the mountain zone have survived for thousands of years without fatal damage. To evaluate the effect of storms on tree growth, the relationships between the stem diameter at breast height (DBH) and the heights of Cr. japonica and coexistent tree species were investigated. Two models based on an expanded allometric equation and a discontinuous piecewise allometric equation, respectively, to represent DBH–height relationships were evaluated. In all plots, the DBH–height relationship of Cr. japonica was discontinuous between small DBH and large DBH individuals. The tops of the large DBH individuals of Cr. japonica were lost to strong winds. However in each instance, they occupied the highest position in the canopy, even if they had lost their tops. In contrast, the DBH–height relationships of subcanopy broadleaved species were continuous in many plots and the equilibrium heights of the dominant broadleaved species were similar and almost in the same order regardless of the canopy heights of Cr. japonica. These results revealed a constant vertical structure in the Cr. japonica forest on Yakushima Island. Our results demonstrate a vertical niche segregation in the forest under high wind pressures and such vertical structure enables effective use of forest space and increases the basal area density.  相似文献   
945.
946.

Aim

To assess the feasibility of transferring to the University of Tsukuba Hospital for proton beam therapy (PBT) during intensive chemotherapy in children with Ewing sarcoma family of tumors (ESFT) who had been diagnosed and started their first-line treatment at prefectural or regional centers for pediatric oncology.

Background

The treatment of ESFT relies on a multidisciplinary approach using intensive neoadjuvant and adjuvant chemotherapies with surgery and radiotherapy. Multi-agent chemotherapy comprising vincristine, doxorubicin, cyclophosphamide, ifosfamide, and etoposide (VDC-IE) is widely used for ESFT, and the interval between each course is very important for maintaining the intensity and effect of chemotherapy.

Materials and methods

Clinical information of patients who received PBT and VDC-IE between April 2009 and May 2016 was collected retrospectively. The intervals between each course of VDC-IE and adverse events were assessed.

Results

Fifteen patients were evaluated. No delays in the intervals of chemotherapy due to transfer were observed. There were no adverse events caused during/just after transfer and no increases in adverse events. The estimated 4-year overall and event-free survival rates were 94.6% and 84.8%, respectively.

Discussion

Although the results of efficacy are preliminary, survival rates were comparable with past studies. More experience and follow-up are required to further assess the efficacy of PBT for patients with ESFT.

Conclusion

Multidisciplinary therapy for children with ESFT involving transfer to our hospital for PBT during VDC-IE was feasible without treatment delay or an increase in adverse events.  相似文献   
947.
Cerebral ischemia/reperfusion is known to induce the generation of reactive oxygen species and inflammatory responses. Numerous studies have demonstrated that naringin (NGIN) has anti-oxidant and anti-inflammatory properties. We previously reported that Citrus kawachiensis contains a large quantity of NGIN in its peel. In the present study, we orally (p.o.) administered dried peel powder of C. kawachiensis to mice of a transient global ischemia model and found in the hippocampus region that it 1) suppressed neuronal cell death, 2) reversed the reduction in the level of phosphorylated calcium-calmodulin-dependent protein kinase II, 3) had the tendency to reverse the reduction in the level of glutathione, and 4) blocked excessive activation of microglia and astrocytes. These results suggested that the dried peel powder of C. kawachiensis had a neuroprotective effect against ischemic brain via anti-oxidative and anti-inflammatory effects. We also showed that these effects of the dried peel powder were more powerful than those obtained with a comparable amount of NGIN alone.  相似文献   
948.
Seminoma constitutes one subtype of human testicular germ cell tumors and is uniformly composed of cells that are morphologically similar to the primordial germ cells and/or the cells in the carcinoma in situ. We performed a genome-wide exploration of the genes that are specifically up-regulated in seminoma by oligonucleotide-based microarray analysis. This revealed 106 genes that are significantly and consistently up-regulated in the seminomas compared to the adjacent normal tissues of the testes. The microarray data were validated by semi-quantitative RT-PCR analysis. Of the 106 genes, 42 mapped to a small number of specific chromosomal regions, namely, 1q21, 2p23, 6p21-22, 7p14-15, 12pll, 12p13, 12q13-14 and 22q12-13. This list of up-regulated genes may be useful in identifying the causative oncogene(s) and/or the origin of seminoma. Furthermore, immunohistochemical analysis revealed that the seminoma cells specifically expressed the six gene products that were selected randomly from the list. These proteins include CCND2 and DNMT3A and may be useful as molecular pathological markers of seminoma.  相似文献   
949.
950.
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