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排序方式: 共有850条查询结果,搜索用时 15 毫秒
821.
Seiji Yamasaki Norimichi Kan Keiichi Mise Takehisa Harada You Ichinose Yoshio Moriguchi Hiroshi Kodama Kohei Satoh Kazuhisa Ohgaki Takayoshi Tobe 《Biotherapy》1993,6(1):63-71
In patients with Stage II or III breast cancer and in patients with liver metastases from breast cancer, we examined cellular interaction in the cytotoxicity against autologous tumor cells by interleukin-2(IL-2)-cultured lymphocytes (CL) and fresh peripheral blood lymphocytes (FPBL) treated with immunochemotherapy including OK-432 and cyclophosphamide. In flow cytometric analysis, CD8 + CD11b+ and CD16+ cells significantly decreased after immuno-chemotherapy in both groups of patients. A protocol study in Stage II or III breast cancer patients showed suppressive activity of FPBL on the cytotoxic activity of CL in 3/9 of the non-treatment group but no suppressive activity and enhancing activity in 3/7 in the immuno-chemotherapy group. Moreover, in 19 patients with liver metastases from breast cancer treated with immuno-chemotherapy including adoptive immunotherapy, FPBL in 6/19 showed enhancing activity, and in 8/19 suppressive activity in the lysis of autologous tumor cells. In assaysin vitro using autologous and allogeneic tumor cells, FPBL showed a partial specificity in cellular interaction against autologous tumor cells. CD4-depleted FPBL inhibited cytotoxicity of CL, while CD8-depleted FPBL enhanced cytotoxicity of CL in patients with liver metastases. These results suggest that immuno-chemotherapy eliminates the suppressive population in FPBL and may induce tumor regression if combined with adoptive immunotherapy using CL.Abbreviations IL-2
interleukin-2
- CL
IL-2-cultured lymphocytes
- FPBL
fresh peripheral blood lymphocytes
- AIT
adoptive immunotherapy 相似文献
822.
Takayoshi Kano 《Journal of human evolution》1980,9(4):243-260
The author studied wild pygmy chimpanzees (Pan paniscus) for about eight months on two separate expeditions between 1975 and 1977, in the study area located at Wamba, Zone de Djolu, in the Republic of Zaire. Most of this paper is based on data obtained through observing the pygmy chimpanzees in their natural surroundings. However, some of them were provisioned and frequently visited the feeding area. Some portion of the data on groupings and food sharing were gathered there. Pygmy chimpanzees groupings, although similar to the common chimpanzee groupings, have larger temporary associations that are almost exclusively bisexual. At least in some greeting contexts, they exhibit patterns of behavior distinctly different from the common chimpanzee. A preliminary investigation of their social interactions revealed strong bonds between males and females, and high female sociability, in contrast to the strong male bonds and female unsociability seen among common chimpanzees. 相似文献
823.
Takayoshi Matsumura 《Journal of Insect Conservation》2004,8(1):59-67
The habitat of Luehdorfia puziloi inexpecta was analyzed by using Quantification Theory Type I, a method for quantifying qualitative data. The investigation area was divided into 92 small sections and was surveyed for its environmental characteristics such as type of trees, tree trunk girth, condition of undergrowth, geography, aspect of slope, and amount of food plants. Environmental factors suitable for oviposition were analyzed using the area density of eggs in each section as the external criterion. The results showed the order of importance of environmental factors to be: aspect of slope > amount of food plants > tree type = tree trunk girth > condition of undergrowth > geography. A slope facing northeast, rich in food plants, with deciduous trees of trunk girth larger than 40 cm, with undergrowth below 30 cm and along a ridgeline was the most preferable habitat for the butterfly. 相似文献
824.
Joni Kujansuu Koh Yasue Takayoshi Koike Anatoly P. Abaimov Takuya Kajimoto Takashi Takeda Morihiko Tokumoto Yojiro Matsuura 《Ecological Research》2007,22(4):582-592
An analysis was performed of the climatic responses of the radial growth of Larix gmelinii (Rupr.) Rupr. at two sites—both of which included contrasting north- and south-facing slopes—in Tura, central Siberia, with
the development of ring width and maximum-density chronologies for each slope. Both residual and standard chronologies of
ring widths were positively correlated with temperature from late May until mid June on all four slopes. By contrast, standard
chronologies of ring widths were negatively correlated with precipitation during the winter (from October to April) and in
May on the north-facing slope at site 1 and on the south-facing slope at site 2 respectively. The negative correlations with
precipitation during the winter and in May on some of the slopes suggested that delayed snowmelt in early spring might inhibit
the radial growth of L. gmelinii, and the effects of snow are likely to vary with topography. Both residual and standard chronologies of maximum densities
were positively correlated with temperature in early July on all four slopes. Maximum densities were also positively correlated
with precipitation during summer of the previous year on all the slopes. These suggest that no major differences exist in
terms of responses of maximum density to climatic factors between the north- and south-facing slopes. 相似文献
825.
Nishida Sachiko Hashimoto Keisuke Kanaoka Masahiro M. Takakura Ko-Ichi Nishida Takayoshi 《Journal of plant research》2017,130(1):125-134
Journal of Plant Research - Reproductive interference (RI) may be a contributing factor to the displacement of native species by an alien congener, and RI strength has been shown theoretically to... 相似文献
826.
The substrate specificities of cinnamyl alcohol dehydrogenase (CAD) of angiosperms and gymnosperms were examined using coniferaldehyde and sinapaldehyd 相似文献
827.
Xiao-Long Yang Toshiyuki Wakimoto Yuya Takeshige Rui He Yoko Egami Takayoshi Awakawa Ikuro Abe 《Bioorganic & medicinal chemistry letters》2013,23(13):3810-3813
New indole–porphyrin hybrid molecules were isolated from Escherichia coli harboring metagenomic DNA from the Japanese marine sponge Discodermia calyx. The indole was appended to the reactive vinyl substituent of the harderoporphyrin chromophore, encoded by the insert DNA. Thus, the chimeric pathway between the heterologously expressed porphyrins and the endogenous indole generated new indole-conjugated chiral porphyrins in E. coli. 相似文献
828.
Takuya Koseki Yozo Miwa Yuichiro Mese Akimasa Miyanaga Shinya Fushinobu Takayoshi Wakagi Hirofumi Shoun Hiroshi Matsuzawa Katsumi Hashizume 《Biochimica et Biophysica Acta (BBA)/General Subjects》2006
A role for N-linked oligosaccharides on the biochemical properties of recombinant α-l-arabinofuranosidase 54 (AkAbf54) defined in glycoside hydrolase family 54 from Aspergillus kawachii expressed in Pichia pastoris was analyzed by site-directed mutagenesis. Two N-linked glycosylation motifs (Asn83–Thr–Thr and Asn202–Ser–Thr) were found in the AkAbf54 sequence. AkAbf54 comprises two domains, a catalytic domain and an arabinose-binding domain classified as carbohydrate-binding module 42. Two N-linked glycosylation sites are located in the catalytic domain. Asn83, Asn202, and the two residues together were replaced with glutamine by site-directed mutagenesis. The biochemical properties and kinetic parameters of the wild-type and mutant enzymes expressed in P. pastoris were examined. The N83Q mutant enzyme had the same catalytic activity and thermostability as the wild-type enzyme. On the other hand, the N202Q and N83Q/N202Q mutant enzymes exhibited a considerable decrease in thermostability compared to the glycosylated wild-type enzyme. The N202Q and N83Q/N202Q mutant enzymes also had slightly less specific activity towards arabinan and debranched arabinan. However, no significant effect on the affinity of the mutant enzymes for the ligands arabinan, debranched arabinan, and wheat and rye arabinoxylans was detected by affinity gel electrophoresis. These observations suggest that the glycosylation at Asn202 may contribute to thermostability and catalysis. 相似文献
829.
Takayoshi Wakagi Takahisa Ohta Kazutomo Imahori 《Bioscience, biotechnology, and biochemistry》2013,77(8):1573-1580
Isoleucyl-tRNA synthetase (IRS) was partially purified from an extreme thermophile, T. thermophilus HB 8. The molecular weight (11.5 ×104) and some kinetic constants were obtained and compared with IRS from other sources.The present IRS catalyzed both isoleucine dependent and valine dependent ATP-PPi exchange reactions (optimum at around 80°C) but not valyl-tRNA formation. The optimum temperature for isoleucyl-tRNA formation was 62°C with E. coli tRNA and 75°C with T. thermophilus tRNA.The enzyme showed a remarkable thermostability. The addition of E. coli or T. thermophilus tRNA enhanced the thermostability of the enzyme, which was shown to be fully active up to 77°C. When E. coli tRNA was used, the loading activity decreased in parallel to the unfolding of the substrate tRNA molecule. From these results the relation is discussed between tRNA conformation and function. 相似文献
830.