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排序方式: 共有258条查询结果,搜索用时 15 毫秒
21.
An aqueous suspension system for phospholipase D-mediated synthesis of PS without toxic organic solvent 总被引:1,自引:2,他引:1
Yugo?Iwasaki Yukiko?Mizumoto Takahiro?Okada Takaya?Yamamoto Kentaro?Tsutsumi Tsuneo?YamaneEmail author 《Journal of the American Oil Chemists' Society》2003,80(7):653-657
Enzymatic synthesis of PS by phospholipase D (PLD)-mediated transphosphatidylation in an aqueous media was investigated. The
purpose of this study was to establish a novel synthetic method where no toxic organic solvents were used. An attempt to react
soybean lecithin (simply dispersed in an aqueous buffer) with an aqueous solution of l-serine and PLD was unsuccessful, giving only 20% of PS. By contrast, a suspension of lecithin adsorbed on fine powders such
as silica was effectively converted into PS in an aqueous solution of l-serine and PLD. After screening various powders for use as the lecithin adsorbent, calcium sulfate was found to be the best
with respect to lecithin conversion. In addition, calcium sulfate did not require prior adsorption of lecithin (i.e., the
reaction proceeded effectively simply by adding the powder to an aqueous mixture of lecithin, l-serine, and PLD). With this “aqueous suspension system” of calcium sulfate, up to 180 mg/mL lecithin was completely converted,
resulting in more than 80% PS in 24 h. The synthesized PS could easily be recovered from the powder by extracting with a mixture
of n-hexane, ethanol, and diluted HCl. 相似文献
22.
Takashi Fujii Masato Nakajima Tsuguo Fukuda Kouichi Nitta Takeshi Komatsubara 《Journal of Electronic Materials》1987,16(4):219-222
Dislocation-free and low dislocation densityn-type conductive GaAs crystals, 50 mm in diameter, were grown by the In and Si co-doping LEC technique. Two-dimensional LED
arrays were fabricated on substrates obtained from these crystals by the MOCVD technique and the influence of the In doping
on the LED characteristics was examined. The light output power of LEDs fabricated on co-doped substrate with an In concentration
of 1 ×1020atoms/cm3 are low and are non-uniformly distributed, as compared with the boat-grown substrate, even though the co-doped substrate
is dislocation-free. However, the LED properties of a substrate with an In concentration of 2 × 1018atoms/cm3 are the same as those of a boat-grown substrate. The light output power of the LEDs becomes higher as the In concentration
in the substrate decreased. 相似文献
23.
Takaya Ichimura Takenori Aoki Guo Fang Song 《Computers & Industrial Engineering》1994,27(1-4):139-142
Under the present situation of diversification of users' needs, rapid technological innovation and internationalization, most Japanese manufacturers are required, as a management strategy, to develop an effective production system with small lot size and short production lead time. In order to meet these requirements, CIMS(computer-integrated manufacturing system) has been developed and introduced for practical use as a new computer-based production system. CIMS is characterized as an integrated system of software and hardware for production management with the purpose of meeting market requirements and counteracting fluctuations in users' demand by maintaining effective production planning and control. The style of CIMS varies with conditions of production and goals of system design. The purpose of this study is to investigate its effectiveness and examine future problems of system integration of CIMS in terms of production management in Japanese manufacturing companies. 相似文献
24.
T Takaya K Maeda H Fukuyama K Watanabe M Takiguchi 《Canadian Metallurgical Quarterly》1997,46(6):764-769
To determine the optimum dose of lidocaine administered in the trachea prior to endotracheal intubation, we divided 102 surgical patients 3-5 years of age into 3 groups, i.e., group 1; 1 mg.kg-1 was sprayed in the trachea, group 2; 2 mg.kg-1 was sprayed in the trachea, group 3; 1 mg.kg-1 was sprayed in the trachea, and 1 mg.kg-1 in the pharynx and the oral cavity simultaneously. The venous serum concentration of lidocaine was measured two times either 1.5, 3, 5, 10, 15, 20, 30 or 45 min after the spray in each case. In group 1, the mean concentration of lidocaine reached the maximum of 1.05 micrograms.ml-1 at 5 min and decreased gradually after that with a small inter-individual variation. In group 2, after reaching the mean maximum concentration of 3.51 micrograms.ml-1 at 3 min, the serum level dropped quickly and then gradually decreased. There were a few cases where serum level was over 7 micrograms.ml-1. In group 2, after reaching the mean maximum concentration of 1.38 micrograms.ml-1 at 5 min, the serum level decreased more slowly, suggesting a slow absorption from the pharynx and/or the oral cavity. We conclude that the recommended dose of lidocaine for endotracheal administration is less than 2 mg.kg-1. 相似文献
25.
A peroral dosage form was examined to deliver recombinant human granulocyte colony-stimulating factor (rhG-CSF) to the colon in beagle dogs. A new gelatin capsule with its inside surface coated with ethylcellulose was prepared for this purpose. RhG-CSF was dissolved with propylene glycol and was filled in the capsule. Several kinds of ethylcellulose-gelatin capsules with an ethylcellulose layer of thickness 46 to 221 mm were used. The capsule was filled with propylene glycol solution containing fluorescein as an absorption marker, castor oil derivative and citric acid. The hardness of the capsule was tested after the gelatin layer was dissolved using a hardness tester and was dependent on the thickness of the ethylcellulose layer of the capsule. The time, Tmax, at which plasma fluorescein level reaches its maximum following oral administration of ethylcellulose capsules was used as a parameter for the in-vivo disintegration time of the ethylcellulose capsule into the colon. Capsules of thickness 84 mm with a Tmax of 4-6 h were filled with rhG-CSF solution containing fluorescein and were administered to dogs. After administration, blood samples were collected for 96 h and the blood total leucocyte (BTL) counts were measured as a pharmacological index of rhG-CSF. The maximum BTL count appeared at 10 h then gradually decreased and returned to its normal level at 48 h. These results suggest the usefulness of ethylcellulose capsules for the delivery of rhG-CSF to the colon and the possibility of a new oral rhG-CSF dosage form has been elucidated. 相似文献
26.
Takaya Satoh 《International journal of molecular sciences》2014,15(10):18677-18692
Insulin is a hormone that regulates the blood glucose level by stimulating various physiological responses in its target tissues. In skeletal muscle and adipose tissue, insulin promotes membrane trafficking of the glucose transporter GLUT4 from GLUT4 storage vesicles to the plasma membrane, thereby facilitating the uptake of glucose from the circulation. Detailed mechanisms underlying insulin-dependent intracellular signal transduction for glucose uptake remain largely unknown. In this article, I give an overview on the recently identified signaling network involving Rab, Ras, and Rho family small guanosine triphosphatases (GTPases) that regulates glucose uptake in insulin-responsive tissues. In particular, the regulatory mechanisms for these small GTPases and the cross-talk between protein kinase and small GTPase cascades are highlighted. 相似文献
27.
Yukihisa Fujinaga Tadashi Namisaki Yuki Tsuji Junya Suzuki Koji Murata Soichi Takeda Hiroaki Takaya Takashi Inoue Ryuichi Noguchi Yuki Fujimoto Masahide Enomoto Norihisa Nishimura Koh Kitagawa Kosuke Kaji Hideto Kawaratani Takemi Akahane Akira Mitoro Hitoshi Yoshiji 《International journal of molecular sciences》2022,23(17)
Primary biliary cholangitis (PBC) has a wide variation in clinical presentation and course. There is no significant correlation between these symptoms and the disease stage, although patients with more advanced stages generally have more symptoms. It is important to develop biomarkers in order to identify patients with an increased risk of complications and end-stage liver disease. This study investigated surrogate markers for risk estimation of PBC-related complications, including a study population of 77 patients with PBC who underwent liver biopsy and were measured for serum levels of macrophage activation markers, soluble CD163 (sCD163), soluble mannose receptor (sMR), and zonulin. Patients with PBC were divided into symptomatic (Group S, n = 20) and asymptomatic (Group A, n = 57) groups. The correlations of histological stages based on both Scheuer and Nakanuma classifications with the three serum markers were investigated. The Nakanuma classification involves grading for liver fibrosis and bile duct loss. The three biomarkers were assessed for their diagnostic ability to identify patients with PBC having high risk of developing complications. The predictive factors of these complications were examined as well. Group S had significantly higher serum sMR (p = 0.011) and sCD163 (p = 0.048) levels versus Group A. A composite index of sMR and sCD163 measurements had significantly better prediction performance than sCD163 alone (p = 0.012), although not when compared to sMR alone (p = 0.129). Serum sMR was an independent factor for developing complications on both univariate (Odds ratio (OR) = 30.20, 95% confidence interval (95% CI): 3.410–267.0, p = 0.00220), and multivariate (OR = 33.70, 95% CI: 3.6600–311.0, p = 0.0019) analyses. Patients with PBC having sMR of ≥56.6 had a higher incidence of clinical complications versus those with a sMR of <56.6. Serum sMR predicts the development of complications in patients with PBC. sMR plus sCD163 showed better predictive power than either marker alone, although the addition of sCD163 did not improve the predictive power of sMR. Future prospective studies are required in order to validate the findings of the present study. 相似文献
28.
We have found that, for dispersion-shifted fiber (DSF) ribbons, the accuracy with which the fiberhole is positioned in the connector ferrule must be less than 0.6 μm to realize a low average insertion loss of about 0.1 dB. By using the high-precision ferrules, we realized MT-type connectors that achieved a very low average insertion loss of 0.11 dB with a maximum of 0.37 dB. These connectors also satisfied mechanical and environmental stability requirements. We have confirmed that our high-precision MT-type connectors can be used for joining DSF ribbon 相似文献
29.
Dislocation-free and low dislocation densityp-type conductive GaAs crystals 50 mm in diameter were successfully grown by the In and Zn co-doping LEC technique. They were
evaluated through the characterizing of LEDs and LDs fabricated on them with epitaxial films grown by the conventional LPE
process. The properties of LEDs fabricated on a co-doped substrate with an In concentration of 1 × 1020 atoms/cm3 were inferior to those fabricated on a boat-grown substrate, even though the co-doped substrate was dislocation-free. On
the other hand, the properties of LEDs and LDs on a co-doped substrate with an In concentration of 2 × 1019 atoms/cm3 were somewhat superior to those fabricated on a boat-grown substrate. There seems to be a particular In concentration in
a GaAs substrate which is the most suitable for application to optical devices containing epitaxial AlGaAs film. 相似文献
30.