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21.
Comparison of the effect of a proteolytic enzyme dispase and a chelator for the preparation of epidermal sheet from nude mice. 总被引:1,自引:0,他引:1
Histochemical studies of epidermal Langerhans cells require well-preserved epidermal sheets. We studied the conditions for the preparation of the epidermal sheets from the skin of the ear, hind limb and trunk of nude mice. Two types of commercial dispase, and ethylenediaminetetraacetic acid (EDTA), were used at several concentrations and the effects were compared. Dermo-epidermal separation was evaluated by the preservation of ATPase activity of Langerhans cells in the epidermal sheet and by the ultrastructure of epidermal cells (Langerhans cells and keratinocytes) as well as epidermal-dermal junction. Good separation depended on the combination of the concentration of the reagent and site of the skin. The concentrations of both dispase and EDTA effective for separation of the epidermis in the nude mouse were lower than those in other mouse strains reported. 相似文献
22.
Chapuis Y-A. Lingfei Zhou Fukuta Y. Mita Y. Fujita H. 《Industrial Electronics, IEEE Transactions on》2007,54(4):1926-1936
In this paper, the authors have developed and implemented a decentralized decision-making strategy using field-programmable gate array (FPGA) technology as a prototype for an integrated controller of a microelectromechanical systems (MEMS) array for air-flow planar micromanipulation. The MEMS array was proposed to be integrated in a hybrid multichip module containing the FPGA-based controller. Algorithms and architectures, used for the decentralized control implementation and the hardware resource optimization, are described. A charge-coupled device camera was used to make each MEMS like an autonomous system when the distributed MEMS chip was tested. Finally, under air-flow condition, the FPGA-based decentralized control system successfully performed an object manipulation. 相似文献
23.
T Hatanaka K Fujita K Ohsumi R Nakagawa Y Fukuda Y Nihei Y Suga Y Akiyama T Tsuji 《Canadian Metallurgical Quarterly》1998,8(23):3371-3374
A series of B-ring modified combretastatin analogues were synthesized and their inhibitory activity against microtubule assembly, cytotoxic activity against Colon 26 adenocarcinoma cancer cell line were evaluated. Among these, pyridone derivative (19) showed strong antimitotic activity and cytotoxicity, along with excellent water-solubility. 相似文献
24.
MQ Fujita N Hashida M Shin H Nakanishi W Yoshihara K Aozasa 《Canadian Metallurgical Quarterly》1998,55(6):600-606
Poly(A)+ mRNA was isolated from leaves of potato plants (Solanum tuberosum L. cv. Desiree) according to standard protocols. This poly(A)+ mRNA was injected via glass microcapillaries into oocytes that were surgically removed from the African clawed toad Xenopus laevis. As a control, oocytes were either injected with H2O or remained untreated. Three days after injection the oocytes were analyzed by two electrode voltage clamping. Current voltage analysis revealed that a K+ channel from potato was functionally expressed in injected oocytes. The identity of this K+ channel was confirmed by its substrate specificity and a shift in the reversal potential. In particular, when the outside K+ concentration was increased the reversal potential of poly(A)+ injected oocytes shifted to more positive values. Furthermore, K+ outward currents declined when the outside K+ concentration was raised from 0.1 to 100 mM. Inward currents increased with an elevation of the K+ concentration. Several pharmaceuticals were tested for their potential to block this K+ channel. As a result, the channel was completely blocked by BaCl2. A three state reaction kinetic model was used to simulate the currents through the K+ transport protein as function of the extracellular K+ concentration. In particular, the simulation revealed current voltage relations that exactly matched the measured ones. Saturation of current voltage curves emerged from the simulation as a consequence of high extracellular potassium concentration. 相似文献
25.
OBJECTIVE: To characterize the existence and role of transforming growth factor-beta (TGF-beta) in otitis media with effusion (OME). STUDY DESIGN: Retrospective. METHODS: The levels of two major TGF-beta isoforms, TGF-beta1 and TGF-beta2, in the middle ear effusions (MEEs) of 44 children were evaluated using enzyme-linked immunospecific assays (ELISAs). Forty-eight MEEs were separated into three clinically relevant groups (i.e., serous, mucoid, and purulent), and TGF-beta levels were correlated with clinical parameters of disease for these MEEs. RESULTS: Both TGF-beta1 and TGF-beta2 were present in the samples. Mean levels of TGF-beta1 (920.36 +/- 437.75 pg/mg total protein) were generally 100-fold greater than those of TGF-beta2 (9.65 +/- 11.19 pg/mg total protein). TGF-beta1 levels were elevated in association with a history of previous tympanostomy tube placements (TTPs) (P = .029) and mucoid effusions (P = .042). TGF-beta2 levels were elevated in association with a history of previous TTPs (P = .100) and chronic (i.e., serous or mucoid) effusions (P = .003). CONCLUSIONS: TGF-beta1 is present in the MEEs of children with OME. Furthermore, TGF-beta1 and TGF-beta2 levels were elevated differentially in the presence of chronic disease indicators in OME, suggesting that these isoforms may have differing roles in the inflammatory processes that characterize OME. 相似文献
26.
Shoji Watanabe Kyoichi Suga Tsutomu Fujita Nobuo Takasaka 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1974,24(11):639-643
Various terpene alcohols were prepared from isoprene oligomers via two steps: epoxidation with peracetic acid and isomerisation with aluminium triisopropoxide. For example, 2-methylene-6-methyl-7-octene-1-o1 was prepared from 2,6-dimethyl-1,7-octadiene. From 2,6-dimethyl-2,7-octadiene, 3,3,6-trimethyl-1,5-heptadiene, 2,7-dimethyl-2,6-octadiene, 2,6-dimethyl-1,3,6-octatriene, 1-methyl-4-isopropenyl-1-cyclohexene, and 1,5-dimethyl-1,5-cyclooctadiene, the corresponding alcohols were obtained, respectively. 相似文献
27.
Lithium naphthalene reacts with acetic acid to give α-anion of lithium acetate. The reaction of this anion with various ketones gives the corresponding β-hydroxy-acids in good yield. 相似文献
28.
Prediction of the biologically active sites in eclosion hormone from the silkworm, Bombyx mori 总被引:1,自引:0,他引:1
Kikuchi T; Okamoto M; Geiser M; Schmitz A; Gohda K; Takai M; Morita T; Horii K; Fujita N 《Protein engineering, design & selection : PEDS》1997,10(3):217-222
The structure-activity relationship of eclosion hormone from the silkworm,
Bombyx mori, was analyzed. First, the probable active residues in silkworm
eclosion hormone and also tobacco hornworm eclosion hormone were predicted
by the average distance map method. To examine the contributions of those
residues to the activity of silkworm eclosion hormone, Gly-substituted
mutants for those predicted residues were produced by site-directed
mutagenesis and their activities were evaluated by a bioassay. Finally,
Glu12, Met24 and Phe25 were estimated to be the crucial residues for the
eclosion hormone activity. The possibility of the development of a blocker
of an eclosion hormone receptor on the basis of the present work is also
discussed.
相似文献
29.
S. Watanabe T. Fujita M. Sakamoto T. Kuramochi H. Kawahara 《Journal of the American Oil Chemists' Society》1993,70(9):927-929
A number of N,N′-diacylalkyldiamines were prepared from the reaction of acid chlorides with 1,8-diaminooctane and 1,12-diaminododecane
and screened for anti-rust properties and antimicrobial activity in spent coolants of water-based cutting fluids. Aqueous
solutions of N,N′-dihexanoyl-1,8-diaminooctane and N,N′-isobutyroyl-1,12-diaminododecane showed good anti-rust properties
for water-based cutting fluids. Aqueous emulsions of N,N′-dibutyroyl-, dipentanoyl-, dihexanoyl- and dioctanoyl-1,12-diaminododecane
showed good lubricities and antimicrobial activity for water-based cutting fluids. 相似文献
30.
Oriented poly-p-phenylene sulphide (PPS) films (thickness 12 and 75 m) and PPS powder were carbonized/graphitized after stabilizing by oxidation, in order to examine the effect of sulphur on graphitizability of the resulting carbons. The films and the powder resulted in carbons with a high and a low graphitizability respectively. An in-plane oriented structure of the PPS film was the most predominant factor to lead to a high graphitizability, and sulphur in the precursor did not lower the graphitizability when it was subjected to solid-phase carbonization. These phenomena are discussed on the basis of analytical data. 相似文献