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11.
We have obtained a partial cDNA and three BAC clones for the porcine insulin-like growth factor binding protein 1 gene (IGFBP-1). Results of fluorescence in situ and radiation hybrid (RH) mapping assigned this gene to porcine chromosome (SSC) 18q24-qter. We found two types of polymerase chain reaction–restriction-fragment-length polymorphisms (PCR–RFLP) in intron 2 by using FokI and AluI.  相似文献   
12.
To develop a bone substitute with shape-generating properties, we focused our attention on dextrin, which has a low viscosity. After considering methods of evaluation for research and development, we started by using cells that are widely used for safe biological evaluations in the field of dentistry and conducted in vitro evaluations. In this experiment, we variously added concentrations of 0.1, 1.0 and 10 mmol/l of dextrin to a culture medium in order to examine the effects on L929 mouse fibroblasts in vitro. As a result, the proliferative activity of the L929 cells was promoted during the culture period as the concentration of added dextrin became lower, and in particular, the 0.1 and 1 mmol/l addition group showed higher values than those of the control group. From the above results, it was revealed that the addition of a low concentration of dextrin in a medium promotes the cell proliferative activity.  相似文献   
13.
The chemokine monocyte chemoattractant protein-1 is a potent chemoattractant for monocytes. Monocyte chemoattractant protein-1 is produced by vascular endothelial cells during inflammatory diseases such as atherosclerosis. In this study, we examined the effects of a thiazolidinedione on monocyte chemoattractant protein-1 expression in human vascular endothelial cells. In human vascular endothelial cells, interleukin-1beta and tumor necrosis factor-alpha induced endogenous monocyte chemoattractant protein-1 protein secretion, mRNA expression and promoter activity. The thiazolidinedione inhibited these effects. In summary, our results indicated that the suppression of the expression of monocyte chemoattractant protein-1 can be accomplished by thiazolidinedione treatment, raising the possibility that thiazolidinedione may be of therapeutic value in the treatment of diseases such as atherosclerosis.  相似文献   
14.
Conclusion and summary The author discussed the floristic and vegetational differences (a) between Formosa and the Philippines, especially between Botel Tobago and Formosa, (b) between Formosa and Continental China, (c) between Japan proper and Continental China together with Corea, Mandschuria and the eastern part of Siberia, (d) between Formosa and Japan proper, and then he discussed (e) the flora of the Liukius, especially the differences between the Yaeyama Islands and Formosa as well as between Yaku Shima and the Amami Islands. In addition he briefly outlined the vegetation of Formosa and Japan, especially the altitudinal distribution of various forest-communities.The conclusions confirmed the floristic discontinuity between Formosa and the Philippines already set forth by E. D. Merrill and several other botanists. Concerning the phytogeographical position of Botel Tobago, the writer confirms the opinion of T. Kano and R. Kanehira that the flora of Botel Tobago is an extension of that of the Batan-Babuyan Islands, the northern border of the Philippines.The floristic close-relation between Japan proper and Continental China is evident from the phytogeographical distribution of the genera of higher plants found in Japan.Data show that the Formosan flora, especially of the highland, is more closely related to the south-western part of China, and also to the Himalayan region, than to the other surrounding regions.The writer considers that the relationship of the flora of Japan proper to that of Formosa is rather weak. He thinks, however, that their floras and vegetations are related to each other through their mutual relation to the lowland and lower montane flora of Continental China situated besides both of them.It is concluded that the flora of the Liukius is an extension of the Formosan flora, judging by the distribution of the genera and species. Looking over the Japan-Liukiu-Formosa area, a conspicuous floristic and synchorological discontinuity is recognized between Yaku Shima and the Amami Islands, and it is conceivable that the Yaku Shima flora is a south-western extension of the flora of Kyushu or Japan proper, as well as the vegetation of Yaku Shima is closely related essentially to that of Japan proper.The writer and his cooperators adopted a new name of Ardisieto-Shiietum Sieboldi to the Shiia forest of Yaku Shima.The writer is unable to make any synchorological or plant-sociological precise comparison between Japan and Continental China along with the eastern part of Siberia and moreover between Formosa and Continental China, because of few or no plant-sociological detailed data of the continental area in the Far Eastern Asia.The author delivered a special lecture on this subject before the botany class in the National Taiwan University, Taipei, Formosa (Taiwan), on December 4th 1953. — Contributions from the Department of Biology, Faculty of Science, Kyushu University, No. 38.  相似文献   
15.
Macaranga myrmecophytes (ant-plants) provide their partner symbiotic ants (plant-ants) with food bodies as their main food, and they are protected by the plant-ants from herbivores. The amount of resource allocated to food bodies determines the plant-ant colony size and consequently determines the intensity of ant defense (anti-herbivore defense by plant-ants). As constraints in resource allocation change as plants grow, the plant-ant colony size is hypothesized to change with the ontogenesis of Macaranga myrmecophyte. To determine the ontogenetic change in the relative size of the plant-ant colony, we measured the dry weights of the whole plant-ant colony and all of the aboveground parts of trees at various ontogenetic stages for a myrmecophytic species (Macaranga beccariana) in a Bornean lowland tropical rain forest. Ant biomass increased as plant biomass increased. However, the rate of increase gradually declined, and the ant biomass appeared to reach a ceiling once trees began to branch. The ant/plant biomass ratio consistently decreased as plant biomass increased, with the rate of decrease gradually accelerating. We infer that the ontogenetic reduction in ant/plant biomass ratio is caused by an ontogenetic change in resource allocation to food rewards for ants related to the physiological changes accompanying the beginning of branching.  相似文献   
16.
A series of indazole derivatives were identified as Sirt 1 activators though high-throughput screening. Optimization of each substituent on the indazole ring led to the identification of compound 13. Compound 13 appeared to give the best Sirt 1 activity of the compounds tested and also showed osteogenesis activity in a cell assay. Sirt 1 activators are therefore potential candidates for the treatment of osteoporosis.  相似文献   
17.
Sea urchin embryos swim by ciliary movement. Hypertonic shock causes deciliation and loss of motility. Within 2-4 h, cilia regenerate and the embryos swim again. Regeneration of cilia occurs multiple times. The adenylate kinase (AK) activity of isolated cilia was studied. A 130-kDa Sp-AK isozyme, present in sperm flagella, is also present in embryonic cilia. AK activity is responsible for approximately 93% of nonmitochondrial ATP regeneration from ADP in embryonic cilia. This is unlike sea urchin sperm flagella, where approximately 31% of the nonmitochondrial ATP regeneration is from the 130-kDa Sp-AK isozyme and approximately 69% from the flagellar creatine kinase (Sp-CK). Embryos were deciliated 1-3 times and after a 2-h period of regeneration the major ciliary axonemal proteins such as the tubulins appeared constant in amount. However, a moderate decrease in ATPase activity, and a large decrease of total AK activity, were measured. The decrease in AK activity paralleled the decrease in embryo swimming velocity. Embryos were deciliated once and cilia regeneration followed for 4 h. ATPase activity recovered to control levels by 3 h, but AK activity and swimming velocity remained lower than in controls. Detergent solubility data and kinetic experiments indicate that, in addition to the 130-kDa Sp-AK, there is at least one additional AK isozyme in embryonic cilia. Analysis of the S. purpuratus genome indicates five AK isozymes in addition to the 130-kDa Sp-AK isozyme. Decreased swimming velocity of embryos with regenerated cilia suggests that regenerated cilia are not as functionally perfect as naturally grown cilia.  相似文献   
18.
19.
We have previously reported that (4R,5R)-5-ethyl-2-imino-4-methylthiazolidine (3) strongly inhibits inducible nitric oxide synthase (iNOS). In a successive search for strong and selective iNOS inhibitors, we, herein, describe the synthesis of the selenium analogue of 3 (4: ES-2133) and its related optically active compounds and examine their in vitro and in vivo inhibitory activity against iNOS. In addition, an alternative synthetic method to the selected compound 4 and its pharmacokinetic profile is also reported.  相似文献   
20.
The large-scale mouse mutagenesis with ENU has provided forward-genetic resources for functional genomics. The frozen sperm archive of ENU-mutagenized generation-1 (G1) mice could also provide a "mutant mouse library" that allows us to conduct reverse genetics in any particular target genes. We have archived frozen sperm as well as genomic DNA from 9224 G1 mice. By genome-wide screening of 63 target loci covering a sum of 197 Mbp of the mouse genome, a total of 148 ENU-induced mutations have been directly identified. The sites of mutations were primarily identified by temperature gradient capillary electrophoresis method followed by direct sequencing. The molecular characterization revealed that all the identified mutations were point mutations and mostly independent events except a few cases of redundant mutations. The base-substitution spectra in this study were different from those of the phenotype-based mutagenesis. The ENU-based gene-driven mutagenesis in the mouse now becomes feasible and practical.  相似文献   
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