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Electronic signals from biological systems such as electrocardiogram(ECG) sometimes are obscured by random noises. When the signal-to-noise ratio(S/N) is low significantly by certain amount of noises, it is sometimes very difficult to get correct biological information from patients. Conventionally, polynomial smoothing methods such as Savitzky-Golay filters are employed, but the efficiency of S/N enhancement is limited. Usually, enhancement factor of S/N is small, at most with the best set of parameters for the polynomial smoothing. As a new solution for the noise reduction, intrinsic ability of factor analysis is applied for the noise reduction, which is separation of meaningful eigenvectors from those of noises. In this study, clean ECGs were generated and certain levels of root-mean-squares(RMS) noises were mixed. These noisy ECGs were subject to the conventional method of noise reduction and a new method of factor analysis and the results of S/N enhancement were compared. As a result, the best enhancement of S/N calculated from levels of RMS noises was achieved by factor analytical method.
Osteoclasts, the multinucleated giant cells that resorb bone, develop from hemopoietic cells of monocyte-macrophage lineage. Differentiation of osteoclasts is strictly regulated by osteoblasts, which deposit bone. In the present study, pyrilamine, an H₁ receptor antagonist, inhibited osteoclast formation in co-cultures of mouse bone marrow cells and calvarial osteoblasts in the presence of 1,25-dihydroxyvitamine D₃ and PGE₂. Pyrilamine also inhibited osteoclastic differentiation of RAW264.7 cells in the presence of TRANCE, suggesting that H₁ receptor-mediated signals crosstalk with TRANCE signals. Further studies will elucidate the precise role of H₁ receptor in TRANCE-mediated osteoclast formation.
Leukotriene B4 (LTB4) is a potent lipid mediator of inflammation formed by the 5-lipoxygenase(5-LO)-catalyzed oxidation of arachidonic acid. LTB4 mediates diverse biological activities through two distinct highly conserved G protein-coupled receptors BL T1 and BL T2. In this study, we investigated the role of LTB4 in receptor activator of nuclear factor-kappaB ligand (RANKL)-induced osteoclast formation. 5-lipoxygenase inhibitor and antagonists for BLT1 or BLT2 were shown to suppress the RANKL-induced osteoclast formation in mouse bone marrow-dereived macrophage (BMM) culture system. Furthermore, RT-PCR analysis demonstrated that rnRNA expression levels for 5-LO, BLT1, and BLT2 on BMM cells were significantly increased by the treatment of RANKL. Taken together, these data suggest the possible role of LTB4 on RANKL-induced osteoclast formation.
Oxidative stress has been emphasized as a molecular etiology for degenerative disease and various biomarkers to measure oxidative stress have been developed. Among them, hyperhomocysteinemia has been focused as a risk factor for stroke. However, there are still discrepancies for the roles of homocysteine on stroke. In the present study, we analyzed oxidative stress levels with malondialdehyde (MDA) and homocysteine levels in chronic male stroke patients (N=7; age, 65.5 ± 6.0 yrs) due to progress of stroke (for 6 months). In addition, vitamin B12, a chemopreventive candidate, has been analyzed to study its effects on MDA or homocysteine. As results, MDA levels were increased due to time period (0.05<p<0.1) and were positively associated with homocysteine levels (p<0.001). However, vitamin B12 did not show any negative association with MDA or homocysteine. In conclusion, we found increased oxidative stress due to stroke progress. Based on positive association with MDA, homocysteine may be involved in oxidative damage during stroke progress. This finding provides a useful mechanism to develop anti oxidative materials to protect stroke.
Platinum complexes having 7 .membered ring structure with Riboflavin(RF) and Flavin mononucleotide(FMN) as leaving group were synthesized to enhance antitumor activity and solubility. Platinum complexes with RF and FMN were determined by ir spectra, nmr spectra, mass and elemental analysis.
NIR(Near-Infrared) spectroscopy is a nondestructive technique and gives fingerprint-type information. Its scanning speed is much fasten compared to other analytical techniques, and usually, minimum sample preparation is required. Particularly, it has been well studied in agricultural and food industry because of fast analysis. Recently, it became important to discriminate the geological origins of natural products for pharmaceutical uses. In this paper, a method of pattern recognition basically based on a form of cluster analysis is described for the discrimination of geological origin of Scutellaria Radix. When 2nd derivative of NIR spectra were used for the calculations of multivariate distances, the results of geological discrimination of the crude drug was successful without any misclassification. The result of successful and perfect discrimination of geological origins of the samples was achieved using several multivariate distance measures, such as Euclidean distance(2-norm), Minkowski distance with norms of 0.5, 1.5 or 3, cosine distance, city block distance(l-norm), or Chebychev distance(oo-norm). With correlation distance, there were a few cases of wrong classification results. On the contrary, with reflectance spectra or 1st derivative spectra, the discrimination was not successful and some distance measures such as Mahalanobis distance or Standardized Euclidean distance were not appropriate for this kind of cluster analysis.
Ethanol extract(EEP) and ether extract of propolis (REP) obtained from honey hives and caffeic acid phenethyl ester (CAPE), an active component of propolis were examined for anti-angiogenetic activities using the chick embryo chorioallantoic membrane (CAM) assay. EEP, REP, and CAPE were demonstrated to show antiangiogenic activities in the CAM assay. The results suggested that anti-angiogenic activities of EEP, REP and CAPE are involved in the antiinflammatory effect of propolis.
Cordyceps species has been used as antiinflammatory, antitoxics, diuretics in folk remedies. Recent research has been reported the effect of anticancer, antidiabetic, antimutagenic, antilipid peroxidation, intestinal immune system modulating activity. Cordyceps pruinosa, which belongs to subgenus Eucordyceps of the Genus Cordyceps, Cordycopidaceae was observed in brown rice and bulled rice supplemented with milk. The activities of MeOH extract and its fraction from cultivated Cordyceps pruinosa on antifatigue activity induced by the mice forced swimming test were evaluated. Acute toxicity was investigated. The result revealed that BuOH and H₂O fractions showed significant antifatigue effect against immobilized stress. LD_(50) of each fraction was below 6g/kg.
We have studied the effect of lauric acid on transdermal flux and the electrical properties of skin. After lauric acid treatment, transdermal flux of ketoprofen increased and it was concentrationdependent. Electrical properties such as resistance and capacitance were evaluated by measuring the skin impedance (Z) as a function of frequency (f) using hairless mouse skin. Bode plot was constructed and it showed the typical shape of skin. Electrical resistance and capacitance were evaluated by the linear regression of the 1/Z² vs f² plot. Electrical resistance of skin decreased rapidly after lauric acid treatment. On the other hand, capacitance increased with time and reached 4 fold larger value than that of the initial value after 24 hours. The results indicate that lauric acid penetrated into the lipid domain of stratum corneum, and thus increased the fluidity of the lipids. Overall, these data provide further mechanistic insight into the action of lauric acid.