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81.
P1-Adenosine 5'-P2-2',3'-ethoxymethylidene nucleosides [A(5')ppN(Em)] from four common nucleosides have been prepared and used for single addition of nucleotides to elongate oligonucleotide chains in the 3'-direction in RNA ligase reaction. U-U-C, T-U-C and A-C-C were used as acceptors. Structural dependence in these acceptors was found to be smaller compared to joining reactions between oligonucleotides. Adenosine analogs including 8-bromo-, 2'-fluoro-, 2'-azido-, 8,2'-O-cyclo-, 8,2'-S-cyclo-adenosine, arabinosyladenine and 2'-deoxyadenosine were added to the 3'-end of A-C-C by adenylation chemically followed by joining with RNA ligase. Symmetrical 5'-pyrophosphates of 8-bromo-, 2'-fluoro- and 2'-azido-adenosine were not recognized as donor substrates.  相似文献   
82.
Previously, we showed that fetal bovine cartilage contains a polypeptide that stimulates the incorporation of [35S]sulfate into proteoglycans synthesized by rat and rabbit costal chondrocytes in culture. In this paper, we report that the cartilage-derived factor (CDF) increases not only [35S]sulfate incorporation but also [3H]thymidine incorporation into rabbit chondrocytes in monolayer culture. The dose-response curve of CDF stimulation of DNA synthesis was similar in profile to that of CDF stimulation of proteoglycan synthesis. In addition, CDF markedly enhanced [3H]uridine incorporation into rabbit chondrocytes and significantly enhanced [3H]serine incorporation into total protein. These findings indicate that fetal bovine cartilage contains a factor that shows somatomedin-like activity in monolayer cultures of rabbit chondrocytes.  相似文献   
83.
On the basis of electron spin resonance results, the 1:1 Cu(II), Co(II), Co(II)-O2, and Ni(III) complexes of bleomycin(BLM) have been compared with the corresponding metal complexes of its biosynthetic intermediate(P-3A). The present study suggests that (1) P-3A is an useful ligand for the clarification of metal-binding sites of BLM; (2) the secondary amine, pyrimidine ring nitrogen, deprotonated peptide nitrogen of histidine residue, and histidine imidazole groups as planar ligand donors, and the α-amino group as axial donor, are substantially important for metal-coordination of BLM; and (3) the sugar and bithiazole portions of BLM probably contribute to stabilization of Co(II)-O2 adduct complex and axial sixth coordination of Cu(II) and Ni(III) complexes.  相似文献   
84.
Adsorption of lipases (EC 3.1.1.3) and various proteins at the air-water interface has been investigated in relation to the mechanism of lipase reaction. Aqueous solutions of lipases and denaturated proteins show surface activity as strong as that of synthetic detergents. However, ths surface activity of esterases and various other proteins is little or none. By foam fractionation it was shown that lipases were adsorbed at the air-water interface and the adsorption followed the equation of Langmuir's adsorption isotherm. The properties of lipase at the interface are discussed in relation to the mechanism of lipase reaction and the differences from the esterase reaction.  相似文献   
85.
Evidence is presented for the selective breakdown of altered tomato β-fructofuranosidase molecules by a neutral protease from Bacillus subtilis.  相似文献   
86.
Antigenic analyses of Lactobacillus bulgaricus, Lactobacillus lactis, Lactobacillus brevis and Lactobacillus buchneri were carried out by double immunodiffusion in agar. Antigens were extracted from whole cells and cell wall preparations with cold trichloroacetic acid. Most strains of the four species possessed antigen 9 in their cell walls. Another antigen, antigen 10, was found in the cell walls of all the strains of L. brevis and L. buchneri, and in some strains of L. lactis, but not in L. bulgaricus. Fractionation of the antigens was attempted using the cell wall extracts of L. lactis L-10 with only antigen 9 and of L. brevis X-1 with both antigens 9 and 10. The partially purified fractions of antigen 9 and of the complex of antigens 9 and 10 were obtained by zone electrophoresis. However, antigen 10 from the complex could not be separated by the same method or gel filtration on Sephadex G-100 since the two antigens 9 and 10 of the complex always behaved together. The fraction of antigen 9 consisted almost entirely of glycerol and glucose as sugar components, the molar ratio being 2:1. The complex of antigens 9 and 10 also consisted of the same sugars, and the molar ratio of glycerol: glucose was 4:1. Inhibition tests indicated that the immunodominant component of antigen 9 was α-methylglucoside (glucose), and most probably the determinant is a glucosylated glycerol teichoic acid. It was considered that the determinant of antigen 10 is a glycerol teichoic acid although glucosamine and galactosamine inhibited effectively the reaction between antigen 10 and its antibody.  相似文献   
87.
88.

To clarify physiological integration for salinity stress alleviation in Zoysia matrella, interconnected clonal stolon ramets were grown in three separate pots [basal (BR), intermediate (IR), and apical ramets (AR)]. Once ramets were well established, two experimental groups were set up: stolons connected with other ramets (Intact) and stolons cut between ramets (Severed). NaCl solution was used for IR, while tap water was used for BR and AR for 49 days. For BR and AR, there was no significant difference in NaCl content in any plant part (green leaves, brown leaves, stolons, and roots) in both groups. Therefore, we concluded that no NaCl translocation in interconnected ramets occurred for both basal and apical directions. For the IR in Intact group, water content in stolons was 1.2 times higher, and NaCl content in green and brown leaves was 16 and 29% lower, respectively than in Severed group. Dry weight of both above ground and below ground parts in Intact groups were 1.3 times higher as compared to that in Severed group. It was considered that tap water treated ramets (BR or AR) translocated water to IR and decreased the amount of NaCl in the body, thereby alleviating salt stress. For the IR in both groups, NaCl content in brown leaves was 2–3 times higher than in other parts. We conclude that Zoysia matrella does not translocate toxic component, such as NaCl between ramets, and does not distribute it to other ramets; however, ramet accumulates NaCl in brown leaves under salt stress condition.

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89.
90.
PurposeEndometrial carcinoma (EC) is a clinically heterogeneous disease characterized by a number of different histological subtypes, and its heterogeneity may be involved in the accumulation of multiple genetic alterations. The aim of this work was to investigate the comprehensive mutational profile of EC tumors, and examine the associations between somatic mutations and clinicopathological features or survival in EC patients.MethodsA total of 100 surgical tumors were obtained from EC patients who had previously undergone surgery. Genomic DNA samples extracted from fresh-frozen tissues were analyzed using the Ion AmpliSeq Cancer Hotspot Panel v2 Kit, covering 50 tumor-related genes.ResultsValidated mutations were detected in 91 of the 100 tumors (91%) and identified in eight of the most frequently mutated genes, namely PTEN (57%), PIK3CA (51%), TP53 (30%), KRAS (23%), CTNNB1 (21%), FBFR2 (13%), FBXW7(10%) and RB1 (9%). PTEN mutations were found to associated with young age (< 60), early-stage, endometrioid histology, non-recurrence and better overall survival (OS). CTNNB1 mutations were associated with young age, endometrioid histology and better OS. On the other hands, TP53 mutations were associated with late-stage, non-endometrioid histology, high-grade, recurrence and worse OS. FBWX7 mutations were associated with late-stage, vascular invasion and lymph node metastasis. FGFR2 mutations correlated with deep (≥ 1/2) myometrial invasion.ConclusionOur comprehensive mutational profile will be useful for understanding and evaluating the molecular characteristics of EC tumors, and may lead to the establishment of novel treatment strategies that improve the survival of patients with EC in the future.  相似文献   
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