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991.
Objectives: The aim of this study was to evaluate the in vitro skin permeation and in vivo transdermal absorption of natural progesterone (Prog) from alcoholic gel-based transdermal formulations containing Prog dissolved stably at a concentration of 3%.

Methods: 3% Prog dissolved gel formulations were prepared containing with water, ethanol, 1,3-butylene glycol, carboxyvinylpolymer, diisopropanolamine, polyoxyethylene (2) oleylether and benzyl alcohol. The gel formulations added different hydrophilic surfactants and isopropyl myristate or propylene glycol dicaprylate (PGDC) as oily solvents were applied in vitro permeation study through excised rat skin on unocclusive condition. The gel formulations added polyoxyethylene (20) oleylether (Oleth-20) as hydrophilic surfactant and PGDC were applied in vivo single- and repeated-dose transdermal absorption study of rat on unocclusive condition.

Results: The results of evaluation of the gel formulations by an in vitro skin permeation study revealed a high flux of Prog from the formulation containing Oleth-20 and Oleth-20 with PGDC. The results of single and repeated in vivo transdermal absorption studies confirmed that good plasma levels of Prog were achieved and maintained by Oleth-20 and PGDC containing gel formulation.

Conclusions: The Oleth-20 and PGDC containing ethanolic gel formulation seemed to have the ability to maintain a high activity of Prog and high diffusivity or solubility of Prog in the epidermis on the practical formulation application.  相似文献   

992.
993.
The removal of microorganisms by drinking water treatment processes has been widely investigated in laboratory-scale experiments using artificially propagated microorganisms. However, this approach cannot be applied to norovirus removal, because this virus does not grow in cell or organ culture, and this fact has hampered our ability to investigate its behavior during drinking water treatment. To overcome this difficulty, our research group previously used recombinant norovirus virus-like particles (rNV-VLPs), which consist of an artificially expressed norovirus capsid protein, in laboratory-scale drinking water treatment experiments. However, the enzyme-linked immunosorbent assay (ELISA) method generally used to detect rNV-VLPs is not sensitive enough to evaluate high removal ratios such as those obtained by ultrafiltration (UF). We therefore developed and applied a real-time immuno-polymerase chain reaction (iPCR) assay for rNV-VLP quantification to investigate norovirus removal by microfiltration (MF), UF, and hybrid precoagulation–MF processes. The rNV-VLP detection limit with the developed iPCR assay was improved at least 1000-fold compared with ELISA. Whereas MF with a nominal pore size of 0.1 μm could not eliminate NV-VLPs, a 4-log reduction was achieved by UF with a molecular weight cutoff of 1 kDa. When MF was combined with precoagulation (≥10 μmol-Fe/L for ferric chloride; ≥20 μmol-Al/L for polyaluminum chloride; ≥40 μmol-Al/L for alum), the performance of the hybrid process in eliminating rNV-VLPs was greater than that achieved by the 1 kDa UF. For all processes, the removal ratios of the bacteriophages MS2 and Qβ were greater than the rNV-VLP removal ratios by 1–2 logs, so neither bacteriophage can be recommended as a possible conservative surrogate for predicting the behavior of native NV during these processes.  相似文献   
994.
Transparent hydroxyapatite (HAp) sintered body with a high crystal orientation and a relative density of 99.7% was fabricated by the pulse electric current sintering method; the c -axis of HAp crystals with a hexagonal column morphology and ca. 200 μm × 25 μm in size was oriented perpendicular to the pressure direction. The sintered temperature increased to 1200°C at a heating rate of 50°C/min for 10 min and a pressure of 50 MPa was applied. The orientation indexes were calculated from X-ray diffraction patterns of the planes perpendicular and parallel to the pressure direction. The optical transmittance was greater than 70% over the wavelength of 700 nm.  相似文献   
995.
The estrogenic activity in water at various localities on Lake Biwa-Yodo River, a representative watershed in Japan, was measured using a recombinant yeast that expresses the human estrogen receptor. The yeast bioassay revealed that the activities of 13 water samples had an average value of 14 pmol/L (3.8 ng/L) (17beta-estradiol equivalent) with a very wide range from 0 to 72 pmol/L (0-19.6 ng/ L), and two of the samples had prominent levels of activity (72 pmol/L (19.6 ng/L) and 56 pmol/L (15.2 ng/L)). We analyzed these two samples with instrumental approaches. A high-performance liquid chromatogram profile showed that the strong activity in one sample, which was collected just downstream of a sewage-treatment plant, would be due to 17beta-estradiol and estrone, whose source is considered to be human urine contained in the effluent of the plant. The activity in the other sample, which was obtained from a tributary river in a primarily residential area with some industrial development (i.e., Osaka City), however, did not correspond to 17beta-estradiol, estrone, or synthetic chemicals known as estrogenic. Analysis of a fraction with estrogenic activity by liquid chromatography-mass spectrometry (LC-MS) provided evidence that the activity in the water sample resulted from the presence of genistein, an isoflavone compound of plant origin.  相似文献   
996.
120 nm period gratings were fabricated by a novel method using ECR-CVD SiNx films. SiNx films deposited on photoresist have a higher etching rate than that on the flat semiconductor substrate. Good use of this difference was made to fabricate gratings whose period is one-half that of the original, formed by a holographic exposure technique  相似文献   
997.
Effects of chlorine on the decrease of estrogenic chemicals   总被引:4,自引:0,他引:4  
The effects of chlorination on the elimination of three estrogenic chemicals such as 17beta-estradiol, nonylphenol and bis-phenol A were investigated using yeast two-hybrid assay (YTA), estrogen receptor (ER) competition assay (ER-CA), and high-performance liquid chromatography/mass spectrometry (LC/MS). The results of YTA, ER-CA and the analysis of LC/MS indicated that the estrogenic activity of the above-mentioned three endocrine disruptors were significantly reduced as a result of chlorination. The decrease in estrogenic activity paralleled a decrease in estrogenic chemicals under the influence of free chlorine. One common characteristic of estrogenic chemicals is the presence of a phenolic ring. Considering that a phenolic ring is likely to undergo some sort of transformation in an aqueous chlorination solution, the above-mentioned results may be applied to the rest of the estrogenic chemicals in natural waters.  相似文献   
998.
Medium temperature carbon dioxide gas turbine reactor   总被引:1,自引:0,他引:1  
A carbon dioxide (CO2) gas turbine reactor with a partial pre-cooling cycle attains comparable cycle efficiencies of 45.8% at medium temperature of 650 °C and pressure of 7 MPa with a typical helium (He) gas turbine reactor of GT-MHR (47.7%) at high temperature of 850 °C. This higher efficiency is ascribed to: reduced compression work around the critical point of CO2; and consideration of variation in CO2 specific heat at constant pressure, Cp, with pressure and temperature into cycle configuration. Lowering temperature to 650 °C provides flexibility in choosing materials and eases maintenance through the lower diffusion leak rate of fission products from coated particle fuel by about two orders of magnitude. At medium temperature of 650 °C, less expensive corrosion resistant materials such as type 316 stainless steel are applicable and their performance in CO2 have been proven during extensive operation in AGRs. In the previous study, the CO2 cycle gas turbomachinery weight was estimated to be about one-fifth compared with He cycles. The proposed medium temperature CO2 gas turbine reactor is expected to be an alternative solution to current high-temperature He gas turbine reactors.  相似文献   
999.
In this research, a computational model that simulates the mental function of multicolor aesthetic evaluation through backpropagation neural networks was constructed. Helmut Leder's psychological model served as the theoretical framework. We determined the macro‐architecture of the computational model through two psychological experiments using the semantic differential (SD) method. The aesthetic score of a multicolor stimulus is defined as the inverse of its factor score on the factor “Pleasure” extracted in the first experiment, and each of the three factors extracted in the second experiment—i.e., “Stability,” “Heaviness,” and “Presence”—is regarded as a simple perceptual feature. The genetic algorithm was then employed to optimize the hidden layer node number, the learning rate, and the momentum constant of each neural network. In two simulation tests, this computational model exhibited some predictive power, implying that the model can be regarded as a relatively successful approximation of the psychological mechanism of multicolor aesthetic evaluation. In addition, the results of the second simulation also show that the perceptual feature “Heaviness” possesses the principal impact on the aesthetic evaluation of multicolor objects, whereas the other two perceptual features “Stability” and “Presence” have a minor influence. The heavier and/or more stable a multicolor object is perceived to be, the less aesthetically pleasing it is. Conversely, the stronger the sense of matter presence a multicolor object elicits, the more aesthetically appealing it is. © 2016 Wiley Periodicals, Inc. Col Res Appl, 42, 216–235, 2017  相似文献   
1000.
To achieve selective hydrodesulfurization (HDS) of fluid catalytic-cracked (FCC) gasoline for producing sulfur-free gasoline (S < 10 ppm), the reactivity of various olefins contained in FCC gasoline on CoMoP/Al2O3 sulfide catalysts was investigated. Isomerization of the CC double bond from the terminal position to an internal position was observed. The steric hindrance around the CC double bond suppresses the reactivity of olefin hydrogenation. The sulfidation temperature of the catalyst has a major influence on olefin hydrogenation active sites. Addition of the appropriate amount of cobalt (Co/Mo ratio approximately 0.6) contributes to the suppression of olefin hydrogenation at high reaction temperature (260 °C). From the comparison of catalytic performance and characterization of our CoMoP/Al2O3 catalyst with an analogous commercial catalyst, it is suggested that the hydrogenation of olefins depends not only on the state of the Mo CUS but also on the steric effects of both olefin structure and MoS2 crystalline structure.  相似文献   
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