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31.
To maintain the stability of L-dopa in hydrogel, a new system composed of two separate layers of L-dopa and hydrogel was developed. L-Dopa sheets were made by immersing L-dopa solution into wiper sheets and by lyophilizing them. Examination for stability of L-dopa in the L-dopa sheet revealed that its stability was maintained for at least 12 weeks, providing the sheet was kept at room temperature in a dark box. In a cutaneous absorption study of L-dopa in rats, an L-dopa sheet was attached to the shaved abdominal skin. A hydrogel composed of cutaneous absorption enhancers, water and ethanol, was spread on vinyl tape (hydrogel sheet), and this sheet was placed over the L-dopa sheet. L-Dopa that was administered transdermally effectively penetrated through the skin: The plasma level of L-dopa peaked at 30 min and remained high between 60 and 180 min after the cutaneous application. Our system, composed of two separated layers of L-dopa and hydrogel, enabled the stability of L-dopa to be maintained without losing transdermal absorption of L-dopa.  相似文献   
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33.
Phosphatidylinositol 4,5-biphosphate (PtdIns(4,5)P2), an important element in eukaryotic signal transduction, is synthesized either by phosphatidylinositol-4-phosphate 5-kinase (PtdIns(4)P 5K) from phosphatidylinositol 4-phosphate (PtdIns(4)P) or by phosphatidylinositol-5-phosphate 4-kinase (PtdIns(5)P 4K) from phosphatidylinositol 5-phosphate (PtdIns(5)P). Two Saccharomyces cerevisiae genes, MSS4 and FAB1, are homologous to mammalian PtdIns(4)P 5Ks and PtdIns(5)P 4Ks. We show here that MSS4 is a functional homolog of mammalian PtdIns(4)P 5K but not of PtdIns(5)P 4K in vivo. We constructed a hemagglutinin epitope-tagged form of Mss4p and found that Mss4p has PtdIns(4)P 5K activity. Immunofluorescent and fractionation studies of the epitope-tagged Mss4p suggest that Mss4p is localized on the plasma membrane, whereas Fab1p is reportedly localized on the vacuolar membrane. A temperature-sensitive mss4-1 mutant was isolated, and its phenotypes at restrictive temperatures were found to include increased cell size, round shape, random distribution of actin patches, and delocalized staining of cell wall chitin. Thus, biochemical and genetic analyses on Mss4p indicated that yeast PtdIns(4)P 5K localized on the plasma membrane is required for actin organization.  相似文献   
34.
The human and rat homologues of a new member of the ADP-ribosylation factor (ARF) family of 21-kDa GTP-binding proteins, termed Arl3, were identified as an expressed sequence tag (human) and as a product of polymerase chain reaction amplification using degenerate probes derived from conserved sequences in members of the ARF family (rat). Alignments of the full-length open reading frames of the human and rat homologues revealed the encoded proteins to be over 97% identical to each other and 43% identical to human ARF1. Northern blots of mRNA from seven human tissues and four rat tissues revealed the presence of a ubiquitous band of about 1 kilobase in length that hybridized with the corresponding Arl3 probes. A number of human tumor cell lines expressed Arl3, as determined by immunoblotting with an Arl-specific antibody, raised against a peptide derived from the human Arl3 sequence. The level of Arl3 expressed in these cell lines was on the order of 0.01% of total cell protein. Purified recombinant human Arl3 was shown to bind guanine nucleotides but lacks ARF activity and intrinsic or ARF GTPase-activating protein-stimulated GTPase activity. In contrast to ARF proteins, the Arl3 protein has reduced dependence on phospholipids and magnesium for guanine nucleotide exchange. Thus, Arl3 is a ubiquitously expressed GTP-binding protein in the ARF family with distinctive biochemical properties consistent with its having unique, but unknown, role(s) in cell physiology.  相似文献   
35.
An optical interconnection technique using a high-silica guided-wave optical circuit composed of channel waveguides and a mixer is proposed for LSI interchip communications. An experimental 4-chip interconnection circuit has 1 Gbit/s transmission capacity performance with an optical power margin of 3 dB.  相似文献   
36.
The fabrication and characteristics of a hybrid-integrated optical gate matrix switch were studied. The switch was composed of a silica-based single-mode guided-wave circuit and two InGaAsP gate array chips, each of which comprised eight laser diode optical gates. The gate array chips were assembled on the guided-wave circuit using a hybrid integration technique. The insertion loss of the fabricated 4×4 matrix switch was scattered among switching paths and ranged from 26 to 33 dB. The switch was applicable to a 400 Mb/s signal system with a bit error rate of 10-9. The numerical analysis shows that the residual reflectivity at the LD gate and waveguide facets caused the loss scattering among the paths and that reduction of the residual reflectivity is essential for improving the switch characteristics  相似文献   
37.
A CO2-laser-irradiated SiO2-Ta2O5 optical-film waveguide has been found to produce up to 2% refractive-index decrease. The usefulness of the CO2 technique has been demonstrated by fabricating a curved multimode channel waveguide with 1 dB/cm propagation loss in the thin film.  相似文献   
38.
Himeno  A. Kobayashi  M. Terui  H. 《Electronics letters》1985,21(22):1020-1021
Single-mode high-silica optical reflection bending and intersecting waveguides are examined under conditions of large bending and intersecting angles (5?90 degrees). The reflection bending waveguide shows a loss of 2 dB at the bending angle of less than 50 degrees. When the intersecting angle was 30 degrees or more, a small intersecting loss (less than 0.1 dB) and a low crosstalk (less than ?20 dB) were attained.  相似文献   
39.
We reformulate the theory of ludics introduced by J.-Y. Girard from a computational point of view. We introduce a handy term syntax for designs, the main objects of ludics. Our syntax also incorporates explicit cuts for attaining computational expressivity. In addition, we consider design generators that allow for finite representation of some infinite designs. A normalization procedure in the style of Krivine’s abstract machine directly works on generators, giving rise to an effective means of computation over infinite designs.The acceptance relation between machines and words, a basic concept in computability theory, is well expressed in ludics by the orthogonality relation between designs. Fundamental properties of ludics are then discussed in this concrete context. We prove three characterization results that clarify the computational powers of three classes of designs. (i) Arbitrary designs may capture arbitrary sets of finite data. (ii) When restricted to finitely generated ones, designs exactly capture the recursively enumerable languages. (iii) When further restricted to cut-free ones as in Girard’s original definition, designs exactly capture the regular languages.We finally describe a way of defining data sets by means of logical connectives, where the internal completeness theorem plays an essential role.  相似文献   
40.
BAYESIAN THRESHOLD AUTOREGRESSIVE MODELS FOR NONLINEAR TIME SERIES   总被引:2,自引:0,他引:2  
Abstract. This paper provides a Bayesian approach to statistical inference in the threshold autoregressive model for time series. The exact posterior distribution of the delay and threshold parameters is derived, as is the multi-step-ahead predictive density. The proposed methods are applied to the Wolfe's sunspot and Canadian lynx data sets.  相似文献   
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