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921.
Phototrophic bacterial cells in the effluent from a lighted upflow anaerobic sludge blanket reactor supplied with a medium containing 142 mg S (as SO4 2–) l–1 accumulated a 6.8% w/w oleic acid content in cells and 19 mg cell-bound oleic acid l–1 in the effluent. Pure cultures of Rhodopseudomonas palustris and Blastochloris sulfoviridis isolated from the effluent also accumulated 5.1 and 6.4% w/w oleic acid contents in cells, respectively. The oleic acid content in the cells recovered from the LUASB reactor effluent was related to the phototrophic bacterial population in the LUASB reactor. The inverse relationship was observed in the LUASB reactor between phototrophic bacterial growth and sulfate concentration in the influent.  相似文献   
922.
923.
 The study was designed to clarify the difference in pharmacokinetics of monoclonal antibodies (mAb) in animal models and humans, and to elucidate the applicability of animal models. 99mTc-labeled murine mAb – against carcinoembryonic antigen (designated BW431/26), and neural cell adhesion molecule (NE150) – and one chimeric mouse/human mAb against nonspecific cross-reacting antigen (chNCA) were administered i.v. to normal mice and athymic mice (370 kBq, 400 ng) xenografted with human cancer cells expressing antigens, and into patients with tumor (925 MBq, 1 mg). The biodistribution of two of the three mAb (not 99mTc-BW431/26) differed clearly in mice and patients. 99mTc-NE150 showed specific uptake in xenografted tumor and otherwise a normal biodistribution; however, clinical examination showed increased uptake in the liver with rapid blood clearance (mean α half-life = 31.1 min) compared with 99mTc-BW431/26 (28.4 h). 99mTc-chNCA demonstrated increased blood clearance and renal excretion in both normal and athymic mice, with accumulation in tumors. Clinical examination showed rapid blood clearance (mean α half-life = 6.4 min) and increased uptake in the liver. High-performance liquid chromatographic analysis of 99mTc-chNCA revealed the immune complex in blood, suggesting uptake of the complex by the reticuloendothelial cells. The biodistribution of radiolabeled mAb in animal and human models was variable and specific for each of the three mAb. The results of animal studies with mAb should be evaluated carefully before being extrapolated to humans, on the basis of the nature of the mAb and interacting substances. Received: 9 April 1997 / Accepted 3 March 1998  相似文献   
924.
925.
Structural studies on an amyloid fibril protein of 14 K daltons (AFj(INO] isolated from a Japanese patient who suffered from familial amyloidotic polyneuropathy were carried out to unambiguously identify its difference from normal human serum prealbumin. Sequence analyses performed by comparing peptide maps prepared from cyanogen bromide fragments and tryptic peptides of purified RCM-amyloid protein with those from RCM-prealbumin indicate that only a valine residue at position 30 in prealbumin is replaced by a methionine residue. Furthermore, it was also proved that AFj(INO) consists of four components; the prealbumin variant and its three related proteins, which are derived by successively accumulated deletion of the N-terminal three amino acid residues (Gly1, Pro2 and Thr3) from the prealbumin variant.  相似文献   
926.
Using Agrobacterium tumefaciens harboring a vector that carriedthe rolC gene under the control of the 35S RNA promoter of cauliflowermosaic virus, we produced several transgenic plants. Two ofthem were periclinal chimeras with altered leaves that had wrinkleddark green margins and inner pale green regions. One chimericplant had shortened internodes, reduced apical dominance, smallflowers and exhibited male sterility, but the other had a normalphenotype. Analysis of proteins, RNA and DNA indicated thatthe inner pale green tissues consisted of transformed cellswhile the outer dark green tissues were composed of non-transformedcells. Histological analysis indicated that mesophyll cellswere distorted and larger intercellular spaces were presentin the transformed pale green regions. Furthermore, in youngleaves, transformed mesophyll cells were larger than non-transformedcells. However, the normal parts had larger numbers of cellsper unit area than the transformed parts. These observationssuggest that ths expression of 35S-rolC in leaves caused inhibitionof cell division in developing leaves and that the undulatingmargins, composed of non-transformed cells, were a consequenceof the requirement for accommodating more cells in less spacewithin the region of rolC-transformed cells. (Received January 29, 1993; Accepted May 17, 1993)  相似文献   
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