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排序方式: 共有5797条查询结果,搜索用时 15 毫秒
1.
Akira Minami Yuuki Kurebayashi Tadanobu Takahashi Tadamune Otsubo Kiyoshi Ikeda Takashi Suzuki 《International journal of molecular sciences》2021,22(6)
Sialidase cleaves sialic acid residues from glycans such as glycoproteins and glycolipids. In the brain, desorption of the sialic acid by sialidase is essential for synaptic plasticity, learning and memory and synaptic transmission. BTP3-Neu5Ac has been developed for sensitive imaging of sialidase enzyme activity in mammalian tissues. Sialidase activity in the rat hippocampus detected with BTP3-Neu5Ac increases rapidly by neuronal depolarization. It is presumed that an increased sialidase activity in conjunction with neural excitation is involved in the formation of the neural circuit for memory. Since sialidase inhibits the exocytosis of the excitatory neurotransmitter glutamate, the increased sialidase activity by neural excitation might play a role in the negative feedback mechanism against the glutamate release. Mammalian tissues other than the brain have also been stained with BTP3-Neu5Ac. On the basis of information on the sialidase activity imaging in the pancreas, it was found that sialidase inhibitor can be used as an anti-diabetic drug that can avoid hypoglycemia, a serious side effect of insulin secretagogues. In this review, we discuss the role of sialidase in the brain as well as in the pancreas and skin, as revealed by using a sialidase activity imaging probe. We also present the detection of influenza virus with BTP3-Neu5Ac and modification of BTP3-Neu5Ac. 相似文献
2.
Abidur Rahman Makoto Kobayashi Kotaro Sugimoto Yuta Endo Manabu Kojima Shigenori Furukawa Takafumi Watanabe Shu Soeda Yuko Hashimoto Keiya Fujimori Hideki Chiba 《International journal of molecular sciences》2021,22(7)
Background: Within the claudin (CLDN) family, CLDN12 mRNA expression is altered in various types of cancer, but its clinicopathological relevance has yet to be established due to the absence of specific antibodies (Abs) with broad applications. Methods: We generated a monoclonal Ab (mAb) against human/mouse CLDN12 and verified its specificity. By performing immunohistochemical staining and semiquantification, we evaluated the relationship between CLDN12 expression and clinicopathological parameters in tissues from 138 cases of cervical cancer. Results: Western blot and immunohistochemical analyses revealed that the established mAb selectively recognized the CLDN12 protein. Twenty six of the 138 cases (18.8%) showed low CLDN12 expression, and the disease-specific survival (DSS) and recurrence-free survival rates were significantly decreased compared with those in the high CLDN12 expression group. We also demonstrated, via univariable and multivariable analyses, that the low CLDN12 expression represents a significant prognostic factor for the DSS of cervical cancer patients (HR 3.412, p = 0.002 and HR 2.615, p = 0.029, respectively). Conclusions: It can be concluded that a reduced CLDN12 expression predicts a poor outcome for cervical cancer. The novel anti-CLDN12 mAb could be a valuable tool to evaluate the biological relevance of the CLDN12 expression in diverse cancer types and other diseases. 相似文献
3.
Sachiyuki Hasegawa Kazuyuki Shimizu Takeshi Kobayashi Masakazu Matsubara 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1985,35(1):33-42
Repeated batch operation using two fermentors (RBTF) to penicillin fermentation was demonstrated by computer simulation to improve productivity. Three operation modes were compared: chemostat, repeated batch operation using a single fermentor (RBSF) and RBTF; in each case account was made of the lag period before growth. The simulated fermentor performances were assessed on the basis of the penicillin productivity and concentration; the simulation was based on published batch fermentation data. It was shown that RBTF was superior to RBSF and chemostat. The advantage of RBTF increased as the lag period became greater. 相似文献
4.
E Kobayashi Y Yoshida A Fujimura T Yamanaka H Endo T Hamamoto Y Kagawa 《Canadian Metallurgical Quarterly》1997,24(12):1775-1777
We studied the in vivo gene transfusion using a gene gun, formerly used in plants and culture cells. The hand-held type gene gun (Helios Gene Gun System) is simple and convenient for effective gene transfection in living animals. This method has some advantages in that there is no need for use of viral vector, independence on the cell cycle and local inducement of plural genes. There is a great possibility for application to local-regional cancer. 相似文献
5.
BACKGROUND/PURPOSE: Recent reports have identified abnormal innervation of the circular muscle layer involving the fine intramuscular nerve fibers in hypertrophic pyloric stenous (HPS). HPS presenting after 3 months of age is rare. The aim of this study was to determine the distribution pattern of nerve fibers in the smooth muscle layers in HPS and correlate this with age at presentation. METHODS: Full-thickness pyloric muscle biopsy specimens were obtained from eight patients with HPS (five age 3 to 5 weeks, two age 3 months, and one age 7 months) and five controls with normal pylorus (age 5 days to 3 years). All specimens were stained with monoclonal antibody to the neural cell adhesion molecule (NCAM) using immunohistochemistry. RESULTS: There were many NCAM-positive nerve fibers in the circular and longitudinal muscle layers in the controls. No NCAM positive nerve fibers were seen in the circular or longitudinal muscle layers in the five cases of HPS in which the patients were less than 5 weeks old. In the two cases in which the patients were 3 months old, occasional NCAM-positive nerve fibers were seen in the circular layer, and moderate numbers of NCAM positive fibers were seen in the longitudinal muscle layers. Moderate numbers of NCAM-positive nerve fibers in the circular muscle layer and many NCAM positive nerve fibers in the longitudinal muscle layers were identified in the 7-month-old HPS patient. CONCLUSIONS: The data suggest that the pyloric muscle lacks innervation in the young HPS infant. Whereas, at 3 months of age the hypertrophied pyloric muscle is partially innervated, and at 7 months of age the pyloric muscle has practically normal innervation. 相似文献
6.
Kobayashi K. Kameyama M. Higuchi T. 《Industrial Electronics, IEEE Transactions on》1997,44(3):418-426
A new token-passing mechanism, priority token passing, which features real-time access and fast detection and recovery of transmission errors, is discussed in detail in comparison with standard token-passing protocols, and its large-scale integration (LSI)-oriented design concept is described. Priority token passing includes only a small performance overhead, due to its switching functions, which can change network topology from ring to broadcast medium. A token-holding node passes the token to another node after determining the successor through priority comparison. Errors occurring during token passing can, thus, be detected and corrected simply and promptly. Priority token passing has a simple hardware implementation, requiring only small additions to the frame control circuitry, and has a small implementation overhead. The priority token-passing protocol and two other important network communication functions, dual ring network reconfiguration and high-level data link control (HDLC) normal response mode-based message transmission, are designed as a single finite-state machine, and implemented into a compact LSI chip. This integrated instrument network (IINET) chip provides complete network communication services and requires only three additional external electronic components for operation 相似文献
7.
N. Karasawa H. Kakehata K. Mishina J. Yamamoto S. Kobayashi 《Photonics Technology Letters, IEEE》2005,17(1):31-33
Using a cross-correlation frequency-resolved optical gating apparatus, the phases and amplitudes of ultrabroad-band optical pulses from a taper fiber have been measured for various input pulse peak powers. The measured waveforms have been compared with calculated waveforms using a finite-difference in the frequency domain method, in which no envelope approximations were used and the variation of the taper shape was taken into account. Excellent agreement between the measured and the calculated waveforms was obtained when the additional dispersion of a normal fiber and an objective was considered. 相似文献
8.
Hitoshi Kurokawa Taku Nakayama Yasunori Kobayashi Ken Suzuki Mutsumi Takahashi Seiichi Takami Momoji Kubo Naotsugu Itoh Parasuraman Selvam Akira Miyamoto 《Catalysis Today》2003,82(1-4):233-240
A modified Monte Carlo (MC) simulation was performed to investigate the hydrogen absorption behavior in Pd and Pd–Ag alloys of the composition PdxAg1−x (x=0.7–0.8) under H2 pressure (0.1 MPa) at different temperatures. The present method employed can consider the dissociative adsorption of hydrogen molecule and the subsequent absorption of hydrogen atom by formalizing the relationship between the pressure of hydrogen molecule and hydrogen atom. The potential parameters were determined to reproduce the solution enthalpy of hydrogen in pure metals. The results are in good agreement with experimental findings as well as previous theoretical studies. We confirmed that our method is useful to simulate the absorption of hydrogen in metals and alloys. 相似文献
9.
Fukuda H. Ebara M. Kobayashi A. Sugiura N. Yoshikawa M. Saisho H. Kondo F. Yoshino S. Yahagi T. 《IEEE transactions on bio-medical engineering》1998,45(3):396-400
To objectively evaluate the parenchymal echo pattern of cirrhotic liver and chronic hepatitis, the authors applied an image analyzing system (IAS) using a neural network. Autopsy specimens in a water tank (n=13) were used to examine the relationship between the diameter of the regenerative nodule and the coarse score (CS) calculated by IAS. CS was significantly correlated with the diameter of the regenerative nodule (p<0.0001, r=0.966). CS is considered to be useful for evaluating the coarseness of the parenchymal echo pattern 相似文献
10.
Mechanical alloying in the Al-Bi alloy system 总被引:1,自引:0,他引:1
Mechanical alloying (MA) was carried out to investigate the MA behaviour of the immiscible Al-10, 30 at % Bi alloys. After the MA processing, the Al and Bi were finely and homogeneously alloyed. The Bi crystallite size decreased to 25 nm and 30 nm in the Al-10 at % Bi and Al-30 at % Bi alloys, respectively. By increasing the MA time, the hardness increased up to a value of 80 H
v, which is larger than that obtained from the rule of mixtures. The lattice parameter of Bi decreased by about 0.27%, which shows the formation of a non-equilibrium hcp Bi super-saturated solid solution. The extended solubility of Al in Bi was 1.9% in the Al-30 at % Bi alloy. Due to the extended solubility, depression of the melting temperature of hcp Bi was confirmed in the mechanically alloyed Al-Bi alloys. The maximum depression in the temperature was about 10 K. The measured values corresponded well with those estimated from the extrapolation of the solidus line. 相似文献