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11.
Grooming initiation among adult males and females of a Japanese macaque troop was analyzed during the non-mating season. Some gestures (“solicitation”) elicited grooming from partners at a high rate. Grooming initiation patterns were divided into two main types: (1) a male often solicited a female to groom him immediately after approaching her and was groomed by her; and (2) a female approached an alpha male selectively, and immediately groomed him. After a female groomed a male, she rarely solicited him to groom her and instead often moved away from him. These results indicated that males were motivated to be groomed, while females were more highly motivated to groom. Sex differences in grooming motivation can be explained by sex differences in the benefit to be groomed.  相似文献   
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The complete amino acid sequence of myoglobin from the triturative stomach of gastropodic molluscBursatella leachii has been determined. It is composed of 146 amino acid residues, is acetylated at the N-terminus, and contains a single histidine residue at position 95 which corresponds to the heme-binding proximal histidine. The E7 distal histidine, which is conserved widely in myoglobins and hemoglobins, is replaced by valine inBursatella myoglobin. The amino acid sequence ofBursatella myoglobin shows strong homology (73–84%) with those ofAplysia andDolabella myoglobins.  相似文献   
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The effects of inorganic and organic nitrogen on the levelsof mRNA for NADH-dependent glutamate synthase (GOGAT) and theprotein were examined in rice cells in suspension culture. Asupply of NH+4, NO-3, glutamine, or asparagine induced the accumulationof the protein and mRNA, but levels of mRNA for ferredoxin-GOGATwere hardly affected. 1Present address: P.C. Center Wakuya-cho, Toda-gun, Miyagi,Japan.  相似文献   
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The nucleotide sequences of 11 variable gene segments coding for rabbit T-cell receptor beta (Tcrb-V) chains were determined by directly sequencing fragments amplified by the cassette-ligation mediated polymerase chain reaction (CLM-PCR) and by modified anchor PCR without the cloning procedure. The nucleotide sequences in two of these 11 rabbit Tcrb-V gene segments coincided with those in two of the four rabbit Tcrb-V gene segments previously reported; the others have not been described. The percentage similarity of each nucleotide sequence of the 11 rabbit Tcrb-V gene segments was analyzed and the segments were divided into nine families, which were homologous to nine human families (Vb 2, 3, 4, 5, 7, 8, 10, 18, and 22), respectively.The nucleotide sequence data reported in this paper have been submitted to the DDBJ, EMBL, and GenBank nucleotide sequence databases and have been assigned the accession numbers D17416-D17426.  相似文献   
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A comparison of the mitochondrial NADH-ubiquinone oxidoreductase and the energy-transducing NADH-quinone oxidoreductase (NDH-1) ofParacoccus denitrificans revealed that both systems have similar electron-transfer and energy-transduction pathways. In addition, both complexes are sensitive to the same inhibitors and contain similar electron carriers, suggesting that theParacoccus NDH-1 may serve as a useful model system for the study of the human enzyme complex. The gene cluster encoding theParacoccus NDH-1 has been cloned and sequenced. It is composed of 18,106 base pairs and contains 14 structural genes and six unidentified reading frames (URFs). The structural genes, URFs, and their polypeptides have been characterized. We also discuss nucleotide sequences which are believed to play a role in the regulation of the NDH-1 gene cluster andParacoccus NDH-1 subunits which may contain the binding sites of substrates and/or electron carriers.  相似文献   
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We examined whether inhibitors of the arachidonic acid cascade inhibited nitric oxide (NO) production, as measured by nitrite concentration, either in macrophages or by their cytosolic fractions. Nitrite production by peritoneal macrophages from mice receiving OK-432 treatment was significantly inhibited by phospholipase A2 inhibitors [dexamethasone and 4-bromophenacyl bromide (4-BPB)], lipoxygenase inhibitors [nordihydroguaiaretic acid (NDGA) and ketoconazole] and a glutathioneS-transferase (leukotrienes LTA4-LTC4) inhibitor (ethacrynic acid). However, caffeic acid and esculetin, inhibitors of 5- and 12-lipoxygenase respectively, were not inhibitory. On the other hand, indomethacin, a cyclooxygenase inhibitor, slightly inhibited whereas another inhibitor, ibuprofen, did not. Inhibition of the nitrite production by dexamethasone, 4-BPB, NDGA and ethacrynic acid was also demonstrated when the macrophages were restimulated ex vivo with OK-432 or with lipopolysaccharide. The inhibitory activity of dexamethasone, NDGA and ethacrynic acid was significantly reduced by ex vivo restimulation with OK-432, whereas that of 4-BPB was hardly affected. Furthermore, the inhibitory activity of dexamethasone, NDGA and ethacrynic acid was much higher when the macrophages were continuously exposed to the agents than when they were pulsed. Meanwhile, inhibition by 4-BPB was almost the same with either treatment. In addition, the inhibitory activity of these agents was not blocked withl-arginine, a substrate of NO synthases, or with arachidonate metabolites (LTB4, LTC4 and LTE4). Ethacrynic acid and 4-BPB, but not dexamethasone and NDGA, also inhibited nitrite production by the cytosolic fractions from OK-432-restimulated peritoneal macrophages, and the inhibitory activity of 4-BPB was superior to that of ethacrynic acid. These agents, however, did not inhibit nitrite production from sodium nitroprusside, a spontaneous NO-releasing compound. These results indicate that dexamethasone, 4-BPB, NDGA and ethacrynic acid inhibited the production of NO by macrophages through at least two different mechanisms: one was inhibited by dexamethasone, NDGA and ethacrynic acid and the other by 4-BPB. Furthermore, 4-BPB and ethacrynic acid directly inhibited the activity of the NO synthase in macrophages, suggesting that the agents work by binding to the active site(s) of the enzyme.  相似文献   
20.
Tumor-specific expression of Qa-2k antigen coded by the Q5k gene on various mouse tumor cells and immunological response of the host mice to the antigen have been demonstrated [Seo et al. (1992) J Exp Med 175: 547; Tanino et al. (1992) Cancer Immunol Immunother 35: 230]. The possibility was examined that Qa-2 antigen is one of the recognition target molecules of immunopotentiator-induced, H-2-nonrestricted tumoricidal lymphocytes of Qa-2 mice. Lymphocytes stimulated in vivo withP. acnes or culture-induced anomalous killers of B6.K1 mice did not exhibit significant in vitro cytotoxicity against B6.K1 lymphoblasts but lysed their Qa-2,3-congenic counterpart B6 lymphoblasts. To demonstrate the Qa-2 specificity of such cytotoxic cells more precisely, an L cell transformant clone (LQ7b/Kb), which expressed the 1 and 2 domains of the Qa-2 antigen (Q7b gene product), was generated by transfecting a cloned plasmid DNA containing a hybrid gene constructed from the 5 half of the Q7b gene and the 3 half of the H-2Kb gene (pQ7b/Kb). Using LQ7b/Kb cells as the target cells and the nylon-wool-nonadherent fraction of lymphocytes fromP. acnes-stimulated (C3H/He × B6.K1)F1 mice (H-2k, Qa-2) as the effector cells of the in vitro cytotoxicity reaction, the presence of cytotoxic cells that recognize the 1/2 region of the Q7b gene product was demonstrated. The cytotoxic activity was dependent on T cells bearing T cell receptors of the / type (TCR/). The (C3H/He × B6.K1)F1 effector cells, as well as the B6.K1 effector cells also lysed BW5147 lymphoma cells (Qa-2k+) derived from AKR mice (Qa-2, H-2k). By target-competition experiments it was shown that some of the effector cells lytic to BW5147 were identical to those that lysed LQ7b/Kb. Therefore some of the tumoricidal cells induced by the immunopotentiator interact with the target tumor cells through recognition of the 1/2 region of the Qa-2k tumor antigen by TCR/.  相似文献   
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