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1.
Formation of a Tree having a Low Lignin Content 总被引:2,自引:0,他引:2
Received 30 September 2001/ Accepted in revised form 26 October 2001 相似文献
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Shigenori Goto Sumitaka Sakai Jiro Kera Yukie Suma Gen-Ichiro Soma Shoshichi Takeuchi 《Cancer immunology, immunotherapy : CII》1996,42(4):255-261
Lipopolysaccharide (LPS) has been recognized as a potent antitumor agent in animal tumor models; however, its use in human
cancer therapy has been limited to only one trial, in which LPS from Salmonella was given intravenously. It was not very successful because of poor tumor response and was also toxic. We originally developed
LPS prepared from Pantoea agglomerans (LPSp), and this was a well-purified, small-molecular-mass (5 kDa) agent. We chose intradermal rather than intravenous administration
in the hope that the former would release LPS slowly into the bloodstream, and thus be less toxic while preserving antitumor
activity. In our animal tumor models, intradermal administration was indeed less toxic and more beneficial for tumor regression
than intravenous administration. We made a pilot study with intradermal administration of LPSp on the treatment of ten advanced
cancer patients. Five of them had evaluable tumor, which had failed earlier to respond to conventional chemotherapy. Cyclophosphamide
was also administered in this trial, in anticipation of its synergistic effect with LPSp. In this study LPSp was injected
intradermally into each patient twice a week, starting with an initial dose of 0.4 ng/kg, and raising it to 600 or 1800 ng/kg.
A 400-mg/m2 dose of cyclophosphamide was given intravenously every 2 weeks. After completion of the dose escalation, the treatment was
continued for at least 4 months, and it was found that 1800 ng/kg LPSp was well tolerated. A significant level of cytokines
was observed in the sera for at least 8 h. These results indicate higher tolerable doses and remarkably more continuous induction
of the cytokines than were reported in a previous study by others using intravenous administration. Three of the five evaluable
tumors showed a significant response to our combined therapy. Intradermally administered, LPS was less toxic and elicited
a tumor response in combination with cyclophosphamide; it can thus can be applied to cancer treatment even in humans.
Received: 3 August 1995 / Accepted: 2 April 1996 相似文献
5.
Genomic DNAs of Borrelia burgdorferi sensu lato isolates obtained in Japan sharing different rRNA gene ribotypes were digested with rare-cutter restriction endonucleases and the fragments obtained were separated by pulsed field gel electrophoresis (PFGE). The sizes of large restriction cleavage bands with MluI endonuclease were quite similar among isolates in each ribotype group. On the other hand, the PFGE profiles obtained with the other enzymes (NruI, Sal I or SplI) were rather divergent, and Japanese isolates were distinguishable from the United States and European isolates. The Japanese isolates classified as ribotypes group II (Borrelia garinii) and III (B. afzelii) showed different PFGE patterns from that of European isolates. The isolates grouped into ribotype IV revealed distinctively different PFGE profiles. These results indicate that the Japanese isolates may be genetically divergent and distinct from the United States and European isolates. 相似文献
6.
Chloroplast DNA (cpDNA) restriction site variation was examined in five species ofDesmodium subgenusPodocarpium (Leguminosae; Papilionoideae; Desmodieae). Twenty four phylogenetically informative cpDNA mutations were scored. The cladistic
analysis of characters based on the 24 mutations resulted in the most parsimonious tree which supports the monophyly of the
subgenus.Desmodium elegans of subgenusDollinera was the sister group of subgenusPodocarpium in this tree. The groupings obtained from the cpDNA characters were consistent with the present infrageneric classification
system for the subgenus except for the infraspecific taxa ofD. podocarpum. Three groups withinD. podocarpum, which were incongruent with the infraspecific classification of the species, were distinguished by a total of four site
mutations. The first group consisted of subsp.podocarpum, subsp.fallax, and subsp.oxyphyllum var.oxyphyllum; the second subsp.oxyphyllum var.oxyphyllum; and the last subsp.oxyphyllum var.oxyphyllum and var.mandshuricum. 相似文献
7.
Yukie Takahashi Masako Sohnaka Minoru Nakao Kenji Miyamoto Masahito Fukunaga 《Microbiology and immunology》1993,37(9):721-727
Thirty-two Borrelia isolates were obtained from the adult stage of ixodid ticks, Ixodes ovatus, collected in various localities in Japan. Borrelial isolates were cultivated and analyzed by polyacrylamide gel electrophoresis, with monoclonal antibodies, by pulsed field gel electrophoresis, and by genomic Southern hybridization. All borrelial isolates showed similar protein profiles and monoclonal antibody reactivities, while plasmid profiles were rather diverse. Genomic hybridization using rRNA gene probes demonstrated the genetic similarities of those isolates. We found no significant differences among the borrelial isolates tested, and the restriction fragment length polymorphism patterns of I. ovatus isolates were quite distinct from those of borrelial strains associated with Lyme disease. Therefore, the isolates of Borrelia obtained from I. ovatus were thought to fall into different genospecies. 相似文献
8.
A mass spectrometric method was developed to determine pH-dependent hydrogen-deuterium exchange at the C-2 position of the imidazole ring of histidine, after converting the amino acid to the methylthiohydantoin derivative. The amount of deuterium exchange in N-acetyl-histidine estimated by the present method was confirmed to be in good agreement with that determined by NMR spectrometry. N-Acetylhistidine was deuterated at various pH's. From the amount of deuterium exchange, a pseudo-first order rate constant (kpsi) was calculated. A pKa value of 7.2 for the amino acid was obtained from the relation between kpsi and pH. This method was applied to estimate the pKa value of beta-146 histidine in human hemoglobin. Human hemoglobin deuterated at various pH's was digested with carboxypeptidase A [EC 3.4.12.2] to release the beta-146 histidine. The amount of deuterium exchange in the isolated histidine was determined to obtain kpsi. From these measurements pKa values of 7.0 for the histidine in oxyhemoglobin and of 8.2 for that in deoxyhemoglobin were found at 36.5 degrees, respectively. 相似文献
9.
K Kajita K Yasuda N Yamakita T Murai M Matsuda H Morita A Mori M Murayama S Tanahashi M Sugiura 《Endocrinologia japonica》1991,38(2):121-129
In an attempt to investigate the clinical significance of anti-pituitary antibodies in patients with hypopituitarism, anti-pituitary antibody in plasma was examined in 10 such patients (7 cases of isolated ACTH deficiency, 1 of partial hypopituitarism, and 2 of Sheehan's syndrome), on two or three occasions with an interval of more than 6 months (longitudinal study). In a total of 16 relatives of these 4 patients (2 cases of Sheehan's syndrome, one in each of partial hypopituitarism and isolated ACTH deficiency) and one patient not involved in the longitudinal study, anti-pituitary antibodies were also examined (family study). Anti-pituitary antibodies reacting with rat pituitary cytoplasmic antigens (pituitary cell antibodies: PCA) and pituitary cell surface antibodies (PCSA) reacting with GH3 cells and/or AtT-20 cells were measured with indirect immunofluorescence. The longitudinal study revealed the disappearance of antibodies in 3 patients, 2 PCA positive and one both PCA and PCSA positive. In 3 patients, altered antibody titers or a newly appearing antibody were found during the follow-up period. In 4 patients, the pituitary antibodies were negative during the follow-up periods. Of 16 family members studied, positive PCA was found in 3 members (2 in the families of patients with PCA positive Sheehan's syndrome, and 1 in the family of the patients with PCA positive partial hypopituitarism). Positive PCSA was found in 4 members (one in each of families of patients with partial hypopituitarism and isolated ACTH deficiency and of two cases of Sheehan's syndrome), and weakly positive PCSA was found in one family member of a patients with PCA positive Sheehan's syndrome.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
10.
Summary Changes in the lysosome structures were examined by electron microscopy during the formation of zoospores inTrebouxia potteri. Lysosomes in vegetative cells were homogeneously filled with electron-dense material. At the beginning of zoospore formation, lysosomes invaginated or evaginated to take up mitochondria, ER, or cytoplasmic ground plasma. The ingested organelles became disorganized within the lysosomes. During this disruption of these organelles, the lysosomal contents became heterogeneous, suggesting a decrease in the amount of enzymes within the lysosomes. Golgi bodies and ER seemed to be involved with the disruption of the organelles, probably supplying some substances necessary for the functioning of the lysosomes. Amount of electron-dense materials decreased and, finally, only one to three small spherical aggregates remained in the lysosomes. Then the lysosomes appeared to shrink via loss of watery substances or cutting off of electron-transparent regions. After these changes in lysosome structure, nuclei started to divide successively for formation of the zoospores. The possibility is proposed that the drastic cytoplasmic changes operated by lysosomes trigger the following morphogenetic events in the formation of zoospores.Abbreviations ER
endoplasmic reticulum
- TGN
trans Golgi network 相似文献