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21.
Filiform papillae, which were densely distributed all over the dorsal surface of the lingual body, were crown-shaped, with a central, circular area that sloped in the anterior direction and several branches that surrounded it in a semicircle from the back of the central area. Dome-shaped, fungiform papillae were scattered among these filiform papillae. At the posterior end of the lingual body, there were four circumvallate papillae. Prominent microridges and elevated intercellular borders were widely distributed in the central area of the filiform papillae and the interpapillar region. On the surface of the branches of the filiform papillae, microridges were rarely seen. On the surface of the fungiform papillae, indistinct microridges were observed. Histologically, the dorsal lingual epithelium revealed three different regions: the epithelium on the anterior side of the filiform papillae, the epithelium on the posterior side of the filiform papillae and the interpapillar epithelium. Whereas the basal and suprabasal cells are similar throughout, differences characterize the intermediate and surface layers. Keratohyalin granules appear predominantly in the intermediate layer in the epithelium on the anterior side of filiform papillae. In the epithelium on the posterior side of the filiform papillae, no keratohyalin granules occur and, instead, tonofibrils are prominent. The cells become significantly flattened. In the interpapillar epithelium, no keratohyalin granules are visible, and the tonofilaments occupy almost the entire cytoplasm of most cells in the intermediate and surface layers. The cells are larger in volume in these layers. 相似文献
22.
A sialidase from Bacteroides fragilis SBT3182 was purified 2,240-fold to apparent homogeneity by ammonium sulfate precipitation and sequential chromatographies on DEAE-Toyopearl 650M, Hydroxyapatite, MonoS and Superose6 columns. The N-terminal amino acid sequence of this sialidase, Ala-Asp-X-Ile-Phe-Val-Arg-Glu-Thr-Arg-Ile-Pro-, was determined. Substrate specificity of this enzyme using a variety of sialoglycoconjugates showed a 1.5- and 2.2-fold preference for sialyl alpha 2-8 linkages when compared with alpha 2-3 and alpha 2-6 bound sialic acids, respectively. The native sialidase had a molecular weight of 165kDa, as determined by Superose6 gel filtration chromatography and consisted of three subunits each of 55kDa by SDS-polyacrylamide gel electrophoresis. This enzyme had optimal activity at pH6.1 with colominic acid as substrate. 相似文献
23.
Concanamycin 4-B, a macrolide antibiotic with an 18-membered lactone ring, is known as a specific inhibitor of the vacuolar type of H+-ATPase, as is bafilomycin A1. The drug was tested for its effect on regulation of the vacuolar pH (pHv) of internodal cells of a fresh water characean alga, Chara corallina, under normal conditions and under salt stress. The pHv was measured either on isolated vacuolar sap with a conventional pH electrode or directly by inserting a pH-sensitive glass microelectrode into the vacuole. Proton-pumping into tonoplast vesicles was almost completely inhibited by concanamycin 4-B at 1 nM. Concanamycin 4-B at 1 μM significantly increased pHv while bafilomycin A1 was ineffective when applied at 1 μM. Concanamycin 4-B did not affect pHv when applied at 0.1 μM and increasing the concentration to 10 μM did not amplify the degree of alkalization. Concanamycin 4-B also inhibited pHv regulation under NaCl stress. When Chara cells were treated with 100 mM NaCl, pHv promptly increased and then recovered to the original level. The reacidification was completely inhibited by concanamycin 4-B (1 μM), suggesting that the reacidification was achieved by the H+-ATPase of the tonoplast. 相似文献
24.
Expression of β-actin and β-tubulin mRNA was examined in androgen-sensitive motoneurons of the spinal nucleus of the bulbocavernosus (SNB) in adult male rats by in situ hybridization histochemistry using complementary DNAs encoding chick β-actin and mouse β-tubulin, respectively. Both hybridizable β-actin and βtubulin mRNAs were localized in the somata and proximal dendrites of SNB motoneurons. Removal of androgen by castration significantly reduced the expression levels of both β-actin and β-tubulin mRNAs in the SNB motoneurons, whereas the changes were prevented by testosterone treatment. In contrast, castration or testosterone treatment induced little or no change in the expression levels of these mRNAs in the much less androgen-sensitive motoneurons of the retrodorsolateral nucleus (RDLN). These results suggest that androgen regulates the expression of β-actin and β-tubulin genes in the SNB motoneurons and may provide evidence for the molecular mechanisms of hormonally induced neuronal plasticity in the SNB motoneurons. 相似文献
25.
Iwasaki Yasunaga Mae Tadahiko Fukazawa Chikafusa Makino Amane Ohira Koji Ojima Kunihiko 《Plant and Soil》1993,(1):211-214
Glutelin accumulation in the apical spikelet of the top primary branch (superior spikelet) and the second spikelet of the lowest secondary branch (inferior spikelet) of the ear of the rice plant (Oryza sativa L.) was characterized during grain filling.In the superior spikelet, the accumulation of dry matter and nitrogen started immediately after flowering and rapidly reached the maturation level by 20 days after heading (DAH). At 7 DAH, total RNA content had already reached its maximum level and glutelin mRNA content 70% of its maximum. The increase in glutelin mRNA was followed by a rapid increase in glutelin between 7 and 16 DAH.In the inferior spikelet dry matter, nitrogen and glutelin accumulation were low immediately after flowering and increased only after grain filling of the superior spikelet was almost complete. Total RNA and glutelin mRNA increased much later at slower rates than in the superior spikelet.It is very likely that the retardation of dry matter, total nitrogen and glutelin accumulation in the inferior spikelet is due to retardation of differentiation and development of endosperm tissue, and to glutelin gene expression in endosperm cells. It is suggested that the delayed development resulted from limited partitioning of nutrients to the inferior spikelet at the early stage of ripening. 相似文献
26.
Sakaba Tomoka Soejima Akiko Fujii Shinji Ikeda Hajime Iwasaki Takaya Saito Hiroaki Suyama Yoshihisa Matsuo Ayumi Kozhevnikov Andrey E. Kozhevnikova Zoya V. Wang Hongfeng Wang Siqi Pak Jae-Hong Fujii Noriyuki 《Journal of plant research》2023,136(4):437-452
Journal of Plant Research - A group of temperate grassland plant species termed the “Mansen elements” occurs in Japan and is widely distributed in the grasslands of continental East... 相似文献
27.
S Ito A Iwasaki J Syundo Y Tamura S Kishi H Mori K Ii Y Matsuda N Katsunuma 《The journal of histochemistry and cytochemistry》1989,37(5):611-615
Human liver guanase was purified and a specific antibody against it was raised in rabbits. The antiserum formed a single precipitin line with human liver extract, and also completely inhibited the activity of the liver enzyme. An immunoblotting study showed that the antibody bound specifically to one band of protein with guanase activity and not to other proteins. Therefore, we concluded that this antiserum against the liver enzyme was suitable for use in immunohistochemical demonstration of guanase. In tissue sections, the immunohistochemical reaction with this antibody was positive in the same locations as the histochemical guanase reaction with DAB (3,3'-diaminobenzidine tetrahydrochloride). 相似文献
28.
A Novel Class of Herbicides (Specific Inhibitors of Imidazoleglycerol Phosphate Dehydratase) 总被引:4,自引:2,他引:2
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Mori I Fonne-Pfister R Matsunaga S Tada S Kimura Y Iwasaki G Mano J Hatano M Nakano T Koizumi S Scheidegger A Hayakawa K Ohta D 《Plant physiology》1995,107(3):719-723
A new mode of herbicidal action was established by finding specific inhibitors of imidazoleglycerol phosphate dehydratase, an enzyme of histidine (His) biosynthesis. Three triazole phosphonates inhibited the reaction of the enzyme with Ki values of 40 [plus or minus] 6.5, 10 [plus or minus] 1.6, and 8.5 [plus or minus] 1.4 nM, respectively, and were highly cytotoxic to cultured plant cells. This effect was completely reversed by the addition of His, proving that the cytotoxicity was primarily caused by the inhibition of His biosynthesis. These inhibitors showed wide-spectrum, postemergent herbicidal activity at application rates ranging from 0.05 to 2 kg/ha. 相似文献
29.
Yoshiaki Iwasaki Hiroyuki Takabatake Marc Monestier Soldano Ferrone 《Immunogenetics》1995,42(2):90-100
The anti-HLA-DQ3 monoclonal antibodies (mAb) KS13, SO1, SO2, SO3, SO4, and SO5 recognize spatially close but distinct antigenic determinants, since they crossinhibit each other in their binding to HLA-DQ3 antigens, but do not share idiotopes recognized in their antigen combining site by syngeneic and anti-id antisera and mAb. Furthermore, mAb SO1, SO3, SO4, and SO5 react also with HLA-DQ allospecificities other than HLA-DQ3. Sequence analysis of the heavy (V
H
) and light (V
L
) chain variable region of the six mAb revealed preferential usage of V
H
36–60 and V
K
12/13 gene families. However, the individual V
H
and V
L
germline gene usage by the six mAb is diverse and the utilization of D, J
H
, and J
L
gene segments is heterogeneous. The diverse usage of V
H
and V
L
gene segments and heterogeneous amino acid sequences of V
H
and V
L
CDR, together with the heterogeneous idiotypic profile, may reflect the complexity of the determinants recognized by the six mAb on HLA-DQ3 antigens. The results we have presented provide for the first time information about the structural basis of the diversity of antibodies recognizing human histocompatibility antigens.The nucleotide sequence data reported in this Papershave been submitted to the GenBank nucleotide sequence database and have been assigned the accession numbers L20499, L20957, L20961, L24557, L24558 and L20962, respectively, for V
H
region genes, and L20956, L20958, L24555, L24556, L20959, and L20960, respectively, for V
L
region genes 相似文献
30.
Nucleotide sequence of a Sendai virus genome region covering the entire M gene and the 3'' proximal 1013 nucleotides of the F gene. 总被引:11,自引:4,他引:7
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Y Hidaka T Kanda K Iwasaki A Nomoto T Shioda H Shibuta 《Nucleic acids research》1984,12(21):7965-7973
We determined the sequence of the 2,138 nucleotides in the Sendai virus genome just following the 3' proximal 3,686 nucleotides which we had previously reported (Nucleic Acids Res. 11, 7317-7330, 1983). This covers the entire third gene of 1,173 nucleotides and the 3' proximal 1,013 nucleotides of the fourth gene. Like the NP and P+C genes, both the third and fourth genes start from consensus sequence R1 (3'-UCCCAC(or UA)UUUC) at the 3' end and the third gene terminates with consensus sequence R2 (3'-AUUCUUUUU) at the 5' end. The third gene was identified as M, and the deduced 348 amino acids indicated that the M protein is rich in basic residues and has hydrophobic domains near the C-terminal. The fourth gene, although sequencing is not complete yet, was identified as F, since a large open reading frame found in the gene contains the characteristic sequence of 20 amino acids located at the N-terminal of the F1 protein. Analyses of the amino acid sequence suggested that the structure of the F gene product is NH2-signal peptide-F2-F1-COOH. 相似文献