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Expression of retinoic acid receptor genes in neural crest-derived cells during mouse facial development 总被引:2,自引:0,他引:2
Retinoic acid (RA) is known as a teratogen that induces abnormalities in facial structures which are made up mainly of neural crest-derived mesenchyme. We investigated expression patterns of RA receptor (RAR) genes (subtypes alpha, beta, gamma) during mouse facial development. The expression of the RAR beta gene is specific for the mesenchyme around developing eyes and nose, whereas the RAR gamma gene is expressed in the mesenchyme differentiating to facial cartilages and bones. In contrast, the RAR alpha gene is expressed weakly and uniformly over the facial region. These results suggest that crucial roles of endogenous RA in facial development depend on differential functions of the RAR subtypes. 相似文献
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Masayuki Taniguchi Mitsuo Tanaka Ryuichi Matsuno Tadashi Kamikubo 《Applied microbiology and biotechnology》1982,14(1):35-39
Summary Rice straw was treated with NaOH, peracetic acid (PA), and sodium chlorite (NaClO2). Quantitative changes in the composition of the treated straw, crystallinity of the treated straw and extracted cellulose, and susceptibility of the treated straw to Trichoderma reesei cellulase were studied. The alkali treatment resulted in a remarkable decrease in hemicellulose as well as lignin. Consequently, the recovery of residual straw after NaOH treatment was lowest among the three chemical reagents evaluated. The treatment with PA or NaCIO2 resulted in a slight loss in hemicellulose and cellulose in the straw. The three chemical treatments caused little or no breakdown of the crystalline structure of cellulose in the straw. The treated straw was solubilized with the culture filtrate of T. reesei. The degree of enzymatic solubilization relative to the amount of residual straw was 69% after treatment with 0.25 N NaOH, 42% after treatment with 20% PA, and 50% after treatments with NaClO2 (twice). The degree of enzymatic solubilization relative to the amount of the untreated straw, however, was 30% after treatment with 0.25 N NaOH, 32% after treatment with 20% PA, and 37% after treatments with NaClO2 (twice). 相似文献
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Properties of [3H]diazepam binding sites on rat blood platelets 总被引:8,自引:0,他引:8
Intact rat blood platelets are shown to possess benzodiazepine binding sites of the peripheral type, binding of [3H]diazepam being strongly inhibited by Ro5-4864 (Ki = 3.6 ± 0.5 nM) but only weakly inhibited by clonazepam (Ki = 35.1 ± 18.2 μM). Binding of [3H]diazepam is specific and saturable. Scatchard analysis reveals a single class of binding sites with KD = 14.7 ± 1.0 nM and Bmax = 564 ± 75 fmoles/108 platelets. The Hill coefficient is 0.94, indicating a lack of binding site heterogeneity or negative cooperativity. Binding reaches equiliibrium at 6 min, with k+1 = 2.9 × 107 M?1 min?1, and is rapidly reversible ( with K?1 = 0.315 min?1. KD derived from the rate constants agrees with that estimated by Scatchard analysis. KD of the crude membrane fraction of platelets is also close to that of intact platelets. Binding of [3H]diazepam is linear with platelet number (between 0.25–2 × 108 platelets), is temperature sensitive with maximum binding at 0°C, and has a broad optimal pH range between pH 5–9. 相似文献
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Zinc deficiency states were produced in rabbit erythrocytes by experimentally induced bleeding anemia and hemolytic anemia. Parallel decreases in total zinc levels and the contents for major zinc protein, carbonic anhydrase I and II isozymes were observed in the erythrocytes. During the process of the anemias the zinc status in the erythrocytes varied remarkably and the relative increase of zinc ions other than that derived from carbonic anhydrase was observed, suggesting that the former zinc ions play an important role in forming a zinc pool in the erythrocytes under the anemic conditions. 相似文献
69.
Kenji Katagiri Toshihiko Takeuchi Keiko Taniguchi Makoto Sasaki 《Analytical biochemistry》1978,86(1):159-165
Pancreatic elastase was isolated from acetone powder of porcine pancreas by a one step purification procedure on a trialanyl CH-Sepharose 4B affinity column. This column exhibited affinity not only for active elastase but also for trypsin and chymotrypsin which were present in the same pancreatic powder. However, as the extent of affinity toward elastase is considerably higher, the proper conditions were determined with which the adsorbed elastase was isolated in a highly purified form. The yield of elastolytic activity ranged from 60–85% and the purified elastase was shown to be one component by polyacrylamide disc electrophoresis. 相似文献