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31.
A novel polarization-beam splitter/switch with a Mach-Zehnder interferometer configuration was fabricated using a silica-based planar lightwave circuit (PLC) on a silicon substrate. The polarization-beam splitter/switch was realized by accurately controlling the waveguide birefringence and the phase state by laser trimming two kinds of stress-applying amorphous silicon film with widths of 50 μm and 95 μm. Fiber-waveguide-fiber insertion loss of 0.5 dB and crosstalk attenuations of over 25.6 dB were attained  相似文献   
32.
Thalidomide, a glutamic acid derivative, has recently been shown to inhibit in vitro angiogenesis, the process of formation of new blood vessels. This Phase II study examined the pharmacokinetics of thalidomide in patients with clinically progressive hormone-refractory prostate cancer. Patients (aged 55 to 80 years) were randomized to two different arms, low dose versus high dose. Patients in the low-dose group were given 200 mg of thalidomide and patients in the high-dose group received 200 mg of thalidomide, with subsequent dose escalations to 1200 mg. Serial serum or blood samples were obtained for pharmacokinetic assessment after administration of a single oral dose or multiple daily dosing of thalidomide and were assayed by reversed-phase HPLC. Pharmacokinetic parameters for both the single and multiple dosing were calculated with ADAPT II. A one-compartment model best fit the data. After single dosing, the oral clearance and apparent volume of distribution for the low-dose regimen (n = 13) were 7.41 +/- 2.05 L/h and 66.93 +/- 34.27 L, respectively, whereas for the high-dose regimen (n = 11), these values were 7.21 +/- 2.89 L/h and 165.81 +/- 84.18 L, respectively. The elimination half-lives for the low and high dose were 6.52 +/- 3.81 and 18.25 +/- 14.08 h, respectively. After the multiple dosing of thalidomide, the oral clearance and apparent volume of distribution for the low-dose group (n = 10) were 6.35 +/- 1.64 L/h and 64.63 +/- 23.20 L, respectively, whereas for the high-dose group (n = 11), these values were 7.73 +/- 2.27 L/h and 167.85 +/- 82.08 L, respectively. The elimination half-lives for the low and high dose were 7.08 +/- 1.87 and 16.19 +/- 9.57 h, respectively. For both the single and multiple dosing of thalidomide, the apparent volume of distribution and half-life were significantly higher for the high-dose group than those for the low-dose group. The higher apparent volume of distribution may be attributable to several factors, such as change in absorption, protein binding, etc. A dose-proportional increase in thalidomide steady-state concentrations was seen after multiple daily dosing of thalidomide.  相似文献   
33.
To clarify the motor function of the infant tongue during sucking, we developed an artificial nipple that contained multiple small built‐in force sensors integrated with a PC‐based system which is capable of measuring tongue–artificial nipple contact pressures in real time. The force sensor is a cantilever structure with a small, thin stainless steel beam where an all‐purpose foil strain gauge is attached to the surface of the beam. An artificial nipple made of an elastomer containing these sensors is connected through an amplifier and an A/D converter to a PC via a USB port. Using this system, measurements were taken in three infants whose oral feeding was well established and in one infant of low birth weight. The results from each force sensor showed a pressure waveform of a nearly simple harmonic motion that indicated a peristalsis‐like movement of the tongue; the sucking frequency was found to be about two times per second. In addition, in the low‐birth‐weight infant, the pressure changed as the infant grew. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
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35.
The optimum structure for high-silica channel waveguides which are connected to input and output graded-index fibers having a 50-μm core diameter and a 1.0-percent refractive-index difference is studied theoretically and experimentally. Theoretical optimum waveguide structure is obtained on the basis of ray optic analysis. For the step-index waveguide with 1.0-percent refractive-index difference, the theoretical minimum coupling loss (input coupling loss + output coupling loss) is 1.7 dB for an optimum core of 38 μm both in depth and width. For the graded-index waveguide with parabolic-index profile in the depth direction and step-index profile in the width direction, the theoretical coupling loss is 1.1 dB for an optimum core of 38 μm in width and 50 μm in depth. These estimations were in good agreement with the experimental results, which were 1.8 dB for the step-index waveguide and 1.3 dB for the graded-index waveguide.  相似文献   
36.
An InGaAsP laser diode with 1.34 ?m wavelength and a high-silica multimode optical waveguide were integrated on a common Si substrate using an alignment guide, which is formed simultaneously with the waveguide, for laser diode mounting. The laser-waveguide coupling efficiency was 30%.  相似文献   
37.
The literature on neutron and photon production from thick targets bombarded by charged particles has been surveyed. The survey covers fourteen journals and some internal reports and conference proceedings, mainly from 1965 up to June 1984. For each paper, applicable information is listed on type and energy of the projectile, the accelerator used, composition and thickness of the target, the experimental method, the calculation, and the quantities obtained. The references on neutron and on photon production are accessed through two indices which list the available projectile-target combinations and the projectile energy range.  相似文献   
38.
Tyrosine phosphorylation is widely recognized as playing important roles in cell differentiation, proliferation, and carcinogenesis. We have used the polymerase chain reaction (PCR) method to identify protein tyrosine kinases that are expressed in the skin. Mixed oligonucleotide probes were used to amplify and screen a neonatal murine skin cDNA pool for clones encoding amino acid contiguities whose conservation is characteristic of the protein tyrosine kinase family. When the PCR products were sequenced, 13 distinct clones were found, of which one is novel to date and has provisionally been named tks (for tyrosine kinase identified from skin). Sequence homology comparison showed that the tks gene is homologous to the src and fes/fps families. Northern blotting using PCR products of tks as a probe revealed that the mRNA of tks is detected ubiquitously and weakly in other tissues such as brain, lung, liver, thymus and kidney. This fact suggests that the tks gene is expressed in widely distributed cell types.  相似文献   
39.
Complement activation and leukosequestration to the lung was studied during cardiopulmonary bypass in eleven patients undergoing cardiac operation without blood transfusion. Six patients (group I) received methylprednisolone before and after the bypass, and the other five (group II) received cepharanthine (biscoclaurin alkaloid) before the bypass associated with methylprednisolone therapy. Leukosequestration to the lung was observed at the time of reperfusion of the lung only in group I, although complement activation estimated by the increase of C 4 a and C 3 a was quite similar in both group. Cepharanthine prevented the sequestration of the leukocyte to the lung may be by its membrane stabilizing effect.  相似文献   
40.
Epidermolysis bullosa acquisita and bullous systemic lupus erythematosus are autoimmune bullous disorders, with tissue-bound and circulating autoantibodies reactive with the noncollagenous NC1 domain of type VII collagen (C-VII). Here, we describe a novel acquired bullous dermatosis with autoantibodies against the triple-helical domain of C-VII. Three patients, all Japanese children, presented with widespread inflammatory tense blisters. Histologically, subepidermal tissue separation was noted with inflammatory infiltrate in the superficial dermis. Direct immunofluorescence staining revealed linear IgG/C3 deposits along the dermal-epidermal junction. Circulating IgG anti-basement membrane zone autoantibodies stained the dermal side of normal skin separated with 1 M NaCl. Direct and indirect immunoelectron microscopy using colloidal gold labeling showed that patient sera reacted with anchoring fibrils. The gold particles were localized both near the lamina densa and on the central banded portion of the fibrils. The sera reacted with C-VII in immunoblots. Epitope analyses with natural and recombinant fragments of C-VII disclosed that the sera did not recognize the NC1 domain of C-VII, but the central triple-helical domain of this anchoring fibril protein. Thus, the present probands show a hitherto unrecognized variant of epidermolysis bullosa acquisita, with autoantibodies against epitopes in the collagenous domain of C-VII.  相似文献   
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