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941.
Mutsumi Imai Michiko Miyazaki H. Henny Yeung Shohei Hidaka Katerina Kantartzis Hiroyuki Okada Sotaro Kita 《PloS one》2015,10(2)
Sound symbolism, or the nonarbitrary link between linguistic sound and meaning, has often been discussed in connection with language evolution, where the oral imitation of external events links phonetic forms with their referents (e.g., Ramachandran & Hubbard, 2001). In this research, we explore whether sound symbolism may also facilitate synchronic language learning in human infants. Sound symbolism may be a useful cue particularly at the earliest developmental stages of word learning, because it potentially provides a way of bootstrapping word meaning from perceptual information. Using an associative word learning paradigm, we demonstrated that 14-month-old infants could detect Köhler-type (1947) shape-sound symbolism, and could use this sensitivity in their effort to establish a word-referent association. 相似文献
942.
Several active concentrates responsible for the long known house fly attracting property of Amanita muscaria (L.) Fr. were obtained through steam distillation and exhaustive solvent extraction of the filtered juice of the fruiting body. Among the active concentrates, one fraction referred to as D3 was isolated as colorless crystals, m.p. 22~23°C, with a chromatographycally proved homogeneity and exhibited a marked attractiveness to house flies, especially to mature females. 相似文献
943.
Eitaro Nakamura Toshio Moritani Akio Kanetaka 《European journal of applied physiology and occupational physiology》1998,78(3):195-200
The present study was conducted to examine further whether adult women who are in a state of high physical fitness possess
high physiological functions, and also to investigate whether those who exercise regularly are able to maintain a high quality
of various physiological functions. The subjects of this study were 249 healthy Japanese adult women (aged 20–70 years). Of
these subjects 30 had jogged or walked regularly for more than 3 years. The physiological ages (PA) and physical fitness ages
(FA) of the individuals were estimated from 17 physiological function tests and 5 physical fitness tests, respectively, by
principal components analyses. The results indicated that there was a significant correlation between PA and FA (r = 0.76, P < 0.01). To examine this relationship in more detail, the subjects were classified into three physical fitness groups (high,
normal and low) based on the deviation from the regression line of FA. Comparison of the mean PA among three physical fitness
groups revealed that the high physical fitness groups demonstrated a much lower PA (physiologically younger), while the low
physical fitness groups showed a relatively higher PA (physiologically older) in spite of their equivalent chronological ages.
From this series of studies, a new concept is proposed where different individuals have different peak physiological capacities,
but that these capacities change with age at similar rates. It is suggested that interventions such as exercise and a proper
diet for promoting health could increase peak functional capacity but have little effect on the rate of decline.
Accepted: 3 March 1998 相似文献
944.
945.
Yamauchi Yasuo; Sugimoto Toshio; Sueyoshi Kuni; Oji Yoshikiyo 《Plant & cell physiology》1996,37(3):279-284
The degradation of storage protein in germinating cucumber seedswas shown to proceed via two distinct steps. First, severalproteases with acidic isoelectric points (pIs) were involvedin solubilization and partial degradation of 11S globulin. Treatmentof seedlings with cycloheximide inhibited this step and theexpression of these proteases. Thus, the first step appearedto be governed by these proteases, which were synthesized denovo after imbibition. The first step was observed in dark-growncotyledons, but the complete degradation of 11S globulin didnot occur in the absence of illumination. An additional protease,with a pI of 4.5, was induced by illumination, and it was involvedin the further cleavage of the partially degraded products ofIIS globulin. Thus, the complete degradation of the storageprotein proceeded via a two-step process in illuminated germinatingseedlings. Light is needed to induce the second step in thedegradation of 11S globulin that supplies the nitrogen requiredfor development of the photosynthetic apparatus in the greeningcotyledon. (Received November 9, 1995; Accepted January 31, 1996) 相似文献
946.
Yasushi Haga Ken Yanagisawa Hiromi Ohto-Ozaki Shin-Ichi Tominaga Toshio Masuzawa Hiroyuki Iwahana 《European journal of biochemistry》2003,270(1):163-170
The ST2 gene, which is specifically induced by growth stimulation in fibroblasts, encodes interleukin-1 receptor-related proteins and is widely expressed in hematopoietic, helper T, and various cancer cells. However, the physiological as well as pathological functions of the ST2 gene products are not yet fully understood. In this study, we analyzed the expression of the ST2 gene in human glioma cell lines and human brain tumor samples with real-time polymerase chain reaction method, the results of which revealed that the expression level of the ST2 gene in glioma cell lines and glioblastoma samples is significantly lower than that in a fibroblastic cell line, TM12, and benign brain tumors, suggesting the reverse relationship between malignancy and ST2 expression. As we could not detect the soluble ST2 protein in the culture fluid of the T98G glioblastic cell line by ELISA, we established stable transformants of T98G that continuously produce and secrete the ST2 protein, in order to study the effect of the ST2 protein on malignancy. Although we could not detect a remarkable difference in proliferation between transformants and control cells in conventional tissue culture dishes, the efficiency of colony formation in soft agar was significantly decreased in the case of cells that continuously produce the ST2 protein. Furthermore, inhibition of colony formation in soft agar was observed in wild-type T98G cells when purified soluble ST2 protein was added to the culture, in a dose-dependent manner. Taken together, the results suggest that the expression of ST2 suppressed the anchorage-independent growth and malignancy. 相似文献
947.
Toshio Yamakawa Hideaki Taira Ichiro Kaneko 《Bioscience, biotechnology, and biochemistry》2013,77(9):2235-2237
A simple method for overproduction of a target protein by genetic engineering techniques has been established. This method involves rearranging the target gene, which contains a ribosome binding sequence for expression, in plurally repeated form, and inserting it in a 3′ lower part of promoters.The chloramphenicol acetyltransferase (CAT) structural gene was used to demonstrate the validity of this method. E. coli harboring a CAT expression plasmid, pUS(CAT)1, which had one inserted CAT gene, was able to produce CAT at the level of only 4% of the total cellular protein according to densitometric scanning on Coomassie-blue-stained SDS-polyacrylamide gel and had the CAT activity of 3.9 × 103 units/mg protein. However, E. coli harboring a CAT expression plasmid, pUS(CAT)4, which had inserted four directly repeated copies of the CAT gene, could synthesize CAT up to 16% of the total cellular protein and had the CAT activity of 2.8 × 104 units/mg protein. This suggests that this method should be useful for overproducing many important peptides or proteins in bacteria. 相似文献
948.
Yusei Miyazaki Rui Li Ayman Rezk Hétoum Misirliyan Craig Moore Nasr Farooqi Mayra Solis Lorna Galleguillos Goiry Omar de Faria Junior Van Duc Dang David Colman Ajit Singh Dhaunchak Jack Antel Jennifer Gommerman Alexandre Prat Simon Fillatreau Amit Bar-Or 《PloS one》2014,9(8)
Clinical trial results demonstrating that B-cell depletion substantially reduces new relapses in patients with multiple sclerosis (MS) have established that B cells play a role in the pathophysiology of MS relapses. The same treatment appears not to impact antibodies directed against the central nervous system, which underscores the contribution of antibody-independent functions of B cells to disease activity. One mechanism by which B cells are now thought to contribute to MS activity is by over-activating T cells, including through aberrant expression of B cell pro-inflammatory cytokines. However, the mechanisms underlying the observed B cell cytokine dysregulation in MS remain unknown. We hypothesized that aberrant expression of particular microRNAs might be involved in the dysregulated pro-inflammatory cytokine responses of B cells of patients with MS. Through screening candidate microRNAs in activated B cells of MS patients and matched healthy subjects, we discovered that abnormally increased secretion of lymphotoxin and tumor necrosis factor α by MS B cells is associated with abnormally increased expression of miR-132. Over-expression of miR-132 in normal B cells significantly enhanced their production of lymphotoxin and tumor necrosis factor α. The over-expression of miR-132 also suppressed the miR-132 target, sirtuin-1. We confirmed that pharmacological inhibition of sirtuin-1 in normal B cells induces exaggerated lymphotoxin and tumor necrosis factor α production, while the abnormal production of these cytokines by MS B cells can be normalized by resveratrol, a sirtuin-1 activator. These results define a novel miR-132-sirtuin-1 axis that controls pro-inflammatory cytokine secretion by human B cells, and demonstrate that a dysregulation of this axis underlies abnormal pro-inflammatory B cell cytokine responses in patients with MS. 相似文献
949.
Soil nematodes play crucial roles in the soil food web and are a suitable indicator for assessing soil environments and ecosystems. Previous nematode community analyses based on nematode morphology classification have been shown to be useful for assessing various soil environments. Here we have conducted DNA barcode analysis for soil nematode community analyses in Japanese soils. We isolated nematodes from two different environmental soils of an unmanaged flowerbed and an agricultural field using the improved flotation-sieving method. Small subunit (SSU) rDNA fragments were directly amplified from each of 68 (flowerbed samples) and 48 (field samples) isolated nematodes to determine the nucleotide sequence. Sixteen and thirteen operational taxonomic units (OTUs) were obtained by multiple sequence alignment from the flowerbed and agricultural field nematodes, respectively. All 29 SSU rDNA-derived OTUs (rOTUs) were further mapped onto a phylogenetic tree with 107 known nematode species. Interestingly, the two nematode communities examined were clearly distinct from each other in terms of trophic groups: Animal predators and plant feeders were markedly abundant in the flowerbed soils, in contrast, bacterial feeders were dominantly observed in the agricultural field soils. The data from the flowerbed nematodes suggests a possible food web among two different trophic nematode groups and plants (weeds) in the closed soil environment. Finally, DNA sequences derived from the mitochondrial cytochrome oxidase c subunit 1 (COI) gene were determined as a DNA barcode from 43 agricultural field soil nematodes. These nematodes were assigned to 13 rDNA-derived OTUs, but in the COI gene analysis were assigned to 23 COI gene-derived OTUs (cOTUs), indicating that COI gene-based barcoding may provide higher taxonomic resolution than conventional SSU rDNA-barcoding in soil nematode community analysis. 相似文献
950.
The sexual maturation in the male house musk shrew, Suncus murinus, was investigated by weighing gonads, accessory sexual organs and various other organs, and measuring testosterone concentrations in the plasma from birth to 50 days of age. The histological and histochemical studies of the testis were also carried out. Testicular weight increased markedly from 10 days of age. On 15 days of age, the activity of delta 5-3 beta-Hydroxysteroid dehydrogenase (HSD) was detected in Leydig cells. In accordance with an increase of HSD activity, the concentrations of plasma testosterone raised rapidly from 15 days of age and reached a peak on Day 30. Growth of prostate glands and seminal vesicles showed a sigmoidal pattern and their significant growth began from Day 25. Sperms were detected first in the seminiferous tubules on Day 28, and most tubules were filled with many sperms on Day 33. From these results, the beginning of sexual maturation, i.e. puberty, of the male shrew is considered to be around Day 25. The weight gain of testes, accessory sexual organs and the body became slower on Day 40. The male animal of Day 40 could mate and impregnate the female. Therefore, the male shrew seems to attain to the sexual maturity between days 35 and 40. 相似文献