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991.
For very low birth weight (VLBW) infants, diagnostic and therapeutic decisions widely depend on hematological values. Although ethnic differences for hematologic parameters have been reported, few studies have been reported for Korean VLBW infants. This study aimed at defining the hematological reference values for medical research and clinical practice. Retrospectively we selected 149 infants confirmed as healthy at birth and had no medical conditions that may have affected the hematological profile. Hematological values obtained within the first 4 h after birth were classified into gestational age and we determined the influence of gender, mode of delivery, sampling site, 1-min and 5-min Apgar scores on these values. Red blood cell (RBC), hemoglobin (Hb) and hematocrit (Hct) values increased, whereas the white blood cell (WBC) and platelets decreased as the gestational age increased. In relation to the mode of delivery and the 5-min Apgar score, WBC, neutrophil, mean corpuscular volume (MCV), RBC, Hb, Hct and the platelets differed selectively. No differences in any hematological values were observed in relation to gender, sampling site, and the 1-min Apgar score. This study should be useful as a guide to the reference range of these hematological values for Korean VLBW infants.  相似文献   
992.
Melissa officinalis L. (Labiatae), Morus alba L. (Moraceae), and Artemisia capillaris Thunb. (Compositae) are suggested to be involved in the regulation of hyperlipidemia. We hypothesized that Ob-X, a mixture of three herbs, Morus alba, Melissa officinalis and Artemisia capillaris [corrected] improves lipid metabolism, body weight gain and adiposity and that peroxisome proliferator-activated receptor alpha (PPARalpha) is associated with these events. Mice fed a high-fat diet for 12 weeks exhibited increases in body weight gain and adipose tissue mass compared with mice fed a low fat diet. However, feeding a high-fat diet supplemented with Ob-X significantly reduced these effects. Ob-X treatment also decreased the circulating levels of triglycerides and total cholesterol, and inhibited hepatic lipid accumulation. Ob-X supplementation was found to increase the hepatic mRNA levels of PPARalpha target enzymes responsible for fatty acid beta-oxidation. Moreover, Ob-X elevated the endogenous expression of a luciferase reporter gene containing three copies of a PPAR response element (PPRE) in NMu2Li liver cells. These data demonstrate that Ob-X regulates body weight gain, adipose tissue mass, and lipid metabolism in part through changes in the expression of hepatic PPARalpha target genes.  相似文献   
993.
Gyeongshingangjeehwan (GGEx), which comprises Liriope platyphylla F.T. Wang & T. Tang (Liliaceae), Platycodongrandiflorum A. DC. (Campanulaceae), Schisandrachinensis K. Koch (Magnoliaceae), and Ephedra sinica Stapf (Ephedraceae), has traditionally been used as an anti-obesity drug in Korean local clinics, although there is no evidence concerning the scientific analyses of its effects and mechanism(s) of action. Thus, we investigated the effects of GGEx on obesity, as well as the mechanism by which GGEx functions, in Otsuka Long-Evans Tokushima Fatty (OLETF) male rats. Compared with obese OLETF control rats, administration of GGEx for 8 weeks significantly decreased food intake and plasma leptin levels as well as body weight gain and abdominal fat in OLETF rats. GGEx treatment not only decreased circulating triglycerides, but also inhibited lipid accumulation in the liver. GGEx increased the hepatic mRNA levels of PPARalpha target genes responsible for fatty acid beta-oxidation. Consistent with the in vivo data, GGEx elevated PPARalpha reporter gene expression in NMu2Li liver cells. These results suggest that GGEx may effectively prevent obesity and hypertriglyceridemia in part through the inhibition of feeding and the activation of hepatic PPARalpha.  相似文献   
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996.
PURPOSEThe purpose of this study was to investigate changes in retention and wear pattern of Locator® and ADD-TOC attachments on a digital milled bar by performing chewing simulation and repeated insertion/removal of prostheses in fully edentulous models.MATERIALS AND METHODSLocator (Locator®; Zest Anchors Inc., Escondido, CA, USA) was selected as the control group and ADD-TOC (ADD-TOC; PNUAdd Co., Ltd., Busan, Republic of Korea) as the experimental group. A CAD-CAM milled bar was mounted on a master model and 3 threaded holes for connecting a bar attachment was formed using a tap. Locator and ADD-TOC attachments were then attached to the milled bar. Simulated mastication and repeated insertion/removal were performed over 400,000 cyclic loadings and 1,080 insertions/removals, respectively. Wear patterns on deformed attachment were investigated by field emission scanning electron microscopy.RESULTSFor the ADD-TOC attachments, chewing simulation and repeated insertion/removal resulted in a mean initial retentive force of 24.43 ± 4.89 N, which were significantly lower than that of the Locator attachment, 34.33 ± 8.25 N (P < .05). Amounts of retention loss relative to baseline for the Locator and ADD-TOC attachments were 21.74 ± 7.07 and 8.98 ± 5.76 N (P < .05).CONCLUSIONCAD-CAM milled bar with the ADD-TOC attachment had a lower initial retentive force than the Locator attachment. However, the ADD-TOC attachment might be suitable for long-term use as it showed less deformation and had a higher retentive force after simulated mastication and insertion/removal repetitions.  相似文献   
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998.
This study examined whether or not the ER stress and Bcl-2 proteins are linked to the protective effect of kaempferol, a phytoestrogen, on ischemia-reperfusion (I/R)-induced cardiac damage. In order to determine if kaempferol modifies the I/R-induced response in H9c2 cardiac muscle cells, the cells were exposed to kaempferol followed by ischemia 12h/reperfusion 4h. kaempferol had a protective effect on the apoptosis induced by I/R in the cardiac muscle cells. The Kaempferol treatment significantly increased the expression level of the anti-apoptotic protein, Bcl-2, but decreased the level of the pro-apoptotic protein, bax. Kaempferol down-regulated the expressions of the endoplasmic reticulum (ER) stress proteins, GRP78, ATF-6alpha, XBP-2, IRE1-alpha, phosphor-eIF-2alpha and CHOP. In ex vivo-Langendorff experiment, the kaempferol treatment regulated the expression of ER stress proteins-CHOP and GRP78. The kaempferol also improved the post-ischemic LVEDP and LVDP significantly after 20, 30, 40 and 50 min of reperfusion compared with the untreated control hearts, which shows that kaempferol offers protection against I/R-associated cardiac dysfunction.  相似文献   
999.
OBJECTIVE: To develop an algorithm to measure the dimensions of an airway oriented obliquely on a volumetric CT, as well as assess the effect of the imaging parameters on the correct measurement of the airway dimension. MATERIALS AND METHODS: An airway phantom with 11 poly-acryl tubes of various lumen diameters and wall thicknesses was scanned using a 16-MDCT (multidetector CT) at various tilt angles (0, 30, 45, and 60 degrees ). The CT images were reconstructed at various reconstruction kernels and thicknesses. The axis of each airway was determined using the 3D thinning algorithm, with images perpendicular to the axis being reconstructed. The luminal radius and wall thickness was measured by the full-width-half-maximum method. The influence of the CT parameters (the size of the airways, obliquity on the radius and wall thickness) was assessed by comparing the actual dimension of each tube with the estimated values. RESULTS: The 3D thinning algorithm correctly determined the axis of the oblique airway in all tubes (mean error: 0.91 +/- 0.82 degrees ). A sharper reconstruction kernel, thicker image thickness and larger tilt angle of the airway axis resulted in a significant decrease of the measured wall thickness and an increase of the measured luminal radius. Use of a standard kernel and a 0.75-mm slice thickness resulted in the most accurate measurement of airway dimension, which was independent of obliquity. CONCLUSION: The airway obliquity and imaging parameters have a strong influence on the accuracy of the airway wall measurement. For the accurate measurement of airway thickness, the CT images should be reconstructed with a standard kernel and a 0.75 mm slice thickness.  相似文献   
1000.
Peptide oral delivery is still a significant challenge because of two major impediments, low absorption efficiency and instability in gastrointestinal tract. The aim of this study was to design, prepare, and evaluate an intestine enzyme-resistant, superior intestine absorptive, and biologically preserved glucagon-like peptide-1 (GLP-1) derivative using the site-specific modification of biotin, which can take advantage of the carrier-mediated active intestine transport. Two series of site-specific Lys34- and Lys26,34-biotin-GLP-1 derivatives were prepared, and their intestine membrane permeabilities, proteolytic stabilities against the intestine enzymes, and bioactivities were then evaluated. Especially, Lys26,34-biotin-GLP-1 was found to have the most promising scores: (i) it displayed a 5.6-fold higher Caco-2 cell monolayer permeability than GLP-1; (ii) it showed an 8.5- and 3.5-fold longer half-life than GLP-1 in rat intestine fluid and homogenate, respectively; and interestingly (iii) it had a well-preserved insulinotropic activity (94.5% vs. GLP-1) in the rat islets. Finally, Lys26,34-biotin-GLP-1 showed a 9-fold higher oral hypoglycemic efficacy (25.3%) than native GLP-1 (2.7%) (P<0.005) after direct peroral administration into type 2 diabetic db/db mice. This study highlights the oral hypoglycemic potential of site-specific Lys26,34-biotinylated GLP-1, and this orally available analogue would find a role in the treatment of type 2 diabetes.  相似文献   
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