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排序方式: 共有614条查询结果,搜索用时 15 毫秒
81.
H Okazaki J Zhang MM Hamawy RP Siraganian 《Canadian Metallurgical Quarterly》1997,272(51):32443-32447
Aggregation of the FcepsilonRI, a member of the immune receptor family, induces the activation of proteintyrosine kinases and results in tyrosine phosphorylation of proteins that are involved in downstream signaling pathways. Here we report that Pyk2, another member of the focal adhesion kinase family, was present in the RBL-2H3 mast cell line and was rapidly tyrosine-phosphorylated and activated after FcepsilonRI aggregation. Tyrosine phosphorylation of Pyk2 was also induced by the calcium ionophore A23187, by phorbol myristate acetate, or by stimulation of G-protein-coupled receptors. Adherence of cells to fibronectin dramatically enhanced the induced tyrosine phosphorylation of Pyk2. Although Src family kinases are activated by FcepsilonRI stimulation and tyrosine-phosphorylate the receptor subunits, the activation and tyrosine phosphorylation of Pyk2 were downstream of Syk. In contrast, tyrosine phosphorylation of Pyk2 by stimulation of G-protein-coupled receptors was independent of Syk. Therefore, the FcepsilonRI-induced tyrosine phosphorylation of Pyk2 is downstream of Syk and may play a role in cell secretion. 相似文献
82.
SC Hung K Nakamura T Matsushita H Okazaki R Shiro K Mamada K Tanaka W Ou T Kurokawa 《Canadian Metallurgical Quarterly》1997,68(6):541-544
AIMS: To objectively assess the psychological and psychosexual morbidity of patients with vulvar vestibulitis. METHODS: 30 patients with variable degrees of vulvar vestibulitis were recruited from a vulval clinic. Each patient underwent a detailed history and clinical examination. Friedrich's criteria were used for the diagnosis of vulvar vestibulitis. Standardised questionnaires to assess psychological and psychosexual function were completed by the patient before review. These questionnaires were the STAI and a modified psychosexual questionnaire introduced by Campion. RESULTS: Patients experienced considerable psychological dysfunction compared with controls. All aspects of psychosexual dysfunction were affected. CONCLUSIONS: When managing patients, psychosexual and psychological issues must be considered in addition to other conventional types of therapy. Vulvar vestibulitis may be a risk factor for developing psychosexual complications including vaginismus, low libido, and orgasmic dysfunction. Consideration of these factors must be an integral part of the management of patients with all chronic vulval conditions. 相似文献
83.
We have clearly resolved four chromosomal bands from four Pichia pastoris (Komagataella pastoris) strains by using contour-clamped homogeneous electric field gel electrophoresis. The size of the P. pastoris chromosomal bands ranged from 1.7 Mb to 3.5 Mb and total genome size was estimated to be 9.5 Mb to 9.8 Mb; however, chromosome-length polymorphisms existed among four strains. Thirteen cloned genes isolated from strain GTS115 were assigned to the separated chromosomes, revealing that different hybridization patterns were observed in the AOX2 and URA3 genes among strains. P. pastoris is frequently used as an efficient host for heterologous gene expressions. We analysed chromosomal stability of strain GTS115-derived recombinant cell expressing human serum albumin during serial cultivation under the condition of vegetative and non-selective growth. No chromosomal rearrangements were observed and the expression constructs integrated into the his4 locus on chromosome I were very stable even at 83 generations, suggesting that stable expression would be carried out even in large-scale fermentation. 相似文献
84.
O Mandelboim S Kent DM Davis SB Wilson T Okazaki R Jackson D Hafler JL Strominger 《Canadian Metallurgical Quarterly》1998,95(7):3798-3803
Proliferation of human CD4+ alphabeta T cells expressing a natural killer cell activating receptor (NKAR) has been shown to be enhanced, particularly in response to low doses of antigen, if the target cells present appropriate human class I major histocompatibility complex (MHC) molecules. Here, we show that NKAR also enhance proliferation and killing of target cells by subsets of CD8+ alphabeta and CD8+ gammadelta T cells, as well as by NK cells. Strikingly, interferon gamma secretion from all of these types of lymphocytes was markedly increased by interaction of the NKAR with their MHC class I ligands, independently of enhancement of proliferation. Thus, the recognition of class I MHC molecules by NKAR on both T cells and NK cells may provide a regulatory mechanism that affects immune responses through the secretion of interferon gamma and possibly other cytokines. It represents a signal for cytokine secretion alternative and/or augmentative to that through the T cell receptor. 相似文献
85.
JG Bri?ón R Arévalo C Crespo IG Bravo K Okazaki H Hidaka J Aijón JR Alonso 《Canadian Metallurgical Quarterly》1998,795(1-2):204-214
The morphological characteristics and distribution of neurocalcin (NC)-immunoreactive elements were studied in the rat main olfactory bulb (OB) using a polyclonal antibody and the avidin-biotin immunoperoxidase method. NC-positive elements were abundant in the glomerular layer (GL), where numerous immunostained external tufted cells and periglomerular cells were detected. Other less abundant NC-immunolabeled populations included middle and internal tufted cells, Van Gehuchten cells, horizontal cells, vertical cells of Cajal, deep short-axon cells and granule cells. This study demonstrates the presence of NC immunoreactivity in subsets of different neuronal types in the rat main OB. This calcium-binding protein has been found in interneurons, and no evidence of immunoreactivity to NC is detected in projecting neurons. Despite the large population of labeled external tufted cells, most of them belong according to morphological criteria to the local circuit group and some others to those with interbulbar and/or intrabulbar connections. The identification of neuronal subpopulations expressing NC provides a further characterization and shows the existence of biochemical differences within morphologically identical neurons. Thus, this marker may be a useful tool in unravelling the circuitries of the rodent OB in both normal and experimental conditions. The exact physiological function of NC in the olfactory system remains unknown. On the basis of similarities to recoverin, it could be involved in mechanisms responsible for sensory adaptation. Additionally, its calcium-binding abilities may contribute to improve the temporal precision of stimuli transmission, or be concerned with general calcium-related events occurring in specific interneuronal groups. 相似文献
86.
The diameter of callus in leg lengthening: 28 tibial lengthenings in 14 patients with achondroplasia
K Mamada K Nakamura T Matsushita H Okazaki R Shiro W Ou K Tanaka T Kurokawa 《Canadian Metallurgical Quarterly》1998,69(3):306-310
A 46-year-old man who had been pulled under water by a tidal wave when an earthquake occurred on July 12, 1993 was carried to our hospital the next day. He soon needed endotracheal intubation and mechanical ventilation because he expectorated sputa with sand and because arterial bloodgas analysis revealed severe hypoxemia. Chest X-ray on admission showed diffuse small nodules and areas of consolidation. Chest CT obtained on July 16 showed centrilobular small nodules bilaterally and alveolar opacities in the peribronchial region. After therapy with antibiotics and frequent bronchial lavages, sputum with sand disappeared on the 14 th hospital day and chest X-ray film and laboratory data showed marked improvement. He was discharged on October 1. A chest CT scan obtained on February 17, 1994 showed improvement of the small nodules. The areas of consolidation had also improved, but remained as linear and nodular opacities, which were considered to be organized lesions. There are few reports concerning radiographic findings particularly CT findings, after aspiration of sea water and sand during near drowning. 相似文献
87.
T Tsujita N Niikawa H Yamashita A Imamura A Hamada Y Nakane Y Okazaki 《Canadian Metallurgical Quarterly》1998,155(3):422-424
Based on volume-flow relationships, CNS agents that are highly lipid soluble (log octanol-water partition coefficient > 2) are expected to have equilibration half-times (T1/2 kE0) that are proportional to brain solubility. Propofol, the most lipophilic anaesthetic in clinical use, has T1/2 kE0 values of 1.7 and 2.9 min in rats and humans, respectively, compared with an expected value of at least 8 min. As a first step in exploring this discrepancy between observed and predicted values, we determined the steady state brain:plasma and brain:blood partition coefficients in rats after a 4-h infusion of propofol. Brain:plasma and brain:blood partition coefficients were 8.2 (SD 1.6) and 3.0 (0.5), respectively. T1/2 kE0 predictions based on brain: blood partitioning in rats are more in agreement with the observed equilibration half-time, suggesting that drug bound to the formed elements of blood participates in the uptake and transfer of propofol to its effect site. 相似文献
88.
Mitamura K Imae T Mouri E Torikai N Matsuoka H Nakamura T 《Journal of nanoscience and nanotechnology》2006,6(1):36-42
Hybrid Langmuir and Langmuir-Blodgett monolayers of a perfluorooctadecanoic acid mixed with a rigid block copolymer, poly(3,5-bis(3,5-bis(benzyloxy)benzyloxy)benzyl methacrylate-randommethacrylic acid)-block-poly(2-perfluorooctylethyl acrylate), which is composed of benzyloxy dendron side chains and perfluorinated side chains, were prepared and characterized by surface pressure-surface area isotherms, atomic force microscopic images and neutron and X-ray reflectometries. The two-dimensionally phase-separated structures of monolayer films and their morphologies with plateau and terrace were confirmed. The monolayers were separated into a dendron layer, a perfluorinated layer, and a carboxyl layer. The layer formation is originated not only in the intermolecular interaction between a perfluorooctadecanoic acid and a block copolymer but also in the geometry of the molecules. Especially, the amphiphilicity of perfluorinated surfactant plays a role to the ordered array of the block copolymers. 相似文献
89.
Interaction control between endohedral metallofullerene and metal substrate by introducing alkanethiol self-assembled monolayer 总被引:1,自引:0,他引:1
Yasutake Y Shi Z Okazaki T Shinohara H Majima Y 《Journal of nanoscience and nanotechnology》2006,6(11):3460-3463
The interaction control between endohedral metallofullerenes and a metal substrate has been demonstrated by introducing hexanethiol, octanethiol, and decanethiol self-assembled monolayers (SAMs) as the interlayer. We observe the electric properties of terbium endohedral metallofullerenes (Tb@C82) on alkanethiol SAMs with different chain lengths by scanning tunneling microscopy (STM) and spectroscopy (STS). Based on the comparison of the high-resolution STM images of a Tb@C82 molecule on hexanethiol and octanethiol SAMs, the interaction between Tb@C82 and a hexanethiol SAM is found to be larger than that between Tb@C82 and an octanethiol SAM; this is because at 68 K, the rotational states of Tb@C82 terminate only on the hexanethiol SAM. Furthermore, we find that the tunneling current-voltage characteristics of Tb@C82 on the hexanethiol SAM show the rectifying effects that are also caused by the molecular energy level shifts of Tb@C82 molecules due to the large interaction. 相似文献
90.
Mikami Y. Nagae Y. Mori Y. Kuwabara K. Saito T. Hayama H. Asada H. Akimoto Y. Kobayashi M. Okazaki S. Asaka K. Matsui H. Nakamura K. Kaneko E. 《Electron Devices, IEEE Transactions on》1994,41(3):306-314
A new concept to produce large thin film transistor liquid crystal displays (TFT-LCD's) without using an optical mask aligner is proposed which emphasizes patterning technology. Some experimental thin film transistors (TFT's) are fabricated according to the concept and operated like conventional transistors fabricated by using an optical mask aligner. The concept includes improvement of printing technology and development of a double-layer resist method. The latter method employs a printed ink pattern and a photoresist. This prevents contamination of thin films by metal impurities which affect electrical characteristics of the TFT's. A special gravure offset printing technology is proposed, composed of a large thixotropy valued UV ink, and a fine, precision etched glass intaglio. The experimental TFT's, with a designed minimum gate length of 10 μm, have comparable electric characteristics to those of conventional poly-Si TFT's 相似文献