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841.
The purpose of this study was to determine whether p53 protein expression in tumor stromal fibroblasts assessed immunohistochemically by the Allred score system is significantly associated with nodal metastasis by invasive ductal carcinoma (IDC), and significantly associated with the outcome of 1042 IDC patients according to adjuvant therapy status, UICC pTNM stage, and triple-negative IDC status, in multivariate analyses with well-known clinicopathological factors. The Allred scores for p53 expression in tumor stromal fibroblasts were significantly associated with the number of nodal metastases, and Allred scores of 4–8 for p53 in tumor stromal fibroblasts significantly increased the hazard rate for distant organ metastasis or for tumor death in the triple-negative IDC patients, and the UICC pTNM stage I, II, and III patients. The results indicated that p53 protein expression in tumor stromal fibroblasts is closely associated with the number of nodal metastases and the outcome of IDC patients. ( Cancer Sci 2009; 00: 000–000)  相似文献   
842.
For the long-term clinical use of the wearable artificial endocrine pancreas, a fail-safe system is an essential mechanism. Several hardware alarm systems have been incorporated for battery-down, and short-run of the pumps. Software alarm systems for overflow or underflow of the AD converter, empty bags, hypoglycemia, hyperglycemia, abnormal values of parameters, and excessive insulin infusion have also been built into the system. The software noise filter was effective in eliminating superimposed artificial noises and the noises induced by muscle exercise. Sudden changes in sensor output during glycemic control of diabetics due to short circuit, or disconnection of the sensor lead, were detected as overflow or underflow of the AD converter. A gradual change in the sensor output was heralded by the hyper- or hypoglycemia alarm sound. These data indicated that the fail-safe system built into the wearable artificial endocrine pancreas is useful for the long-term glycemic control of diabetics.  相似文献   
843.

Purpose  

The purpose of this study was to investigate whether slow-rate freezing or vitrification is better for cryopreservation of ovary tissues pretreated with gonadotropin-releasing hormone agonist.  相似文献   
844.
845.

Background

The Rho small GTPase regulates myosin II activity through the phosphorylation of the myosin light chain (MLC) by activating Rho-kinase, which is a target of Rho. Several lines of evidence point to an important role of Rho in the action of lysophosphatidic acid (LPA) and thrombin in provoking neurite retraction in N1E-115 neuroblastoma cells.

Results

Here we examined whether Rho-kinase and myosin II are involved in neurite retraction in N1E-115 cells. We showed that the expression of constitutively active forms of Rho-kinase induced neurite retraction in N1E-115 cells and MLC phosphorylation in NIH 3T3 cells, whereas the expression of dominant negative forms of Rho-kinase inhibited the LPA-induced neurite retraction in N1E-115 cells and the serum-induced MLC phosphorylation in NIH 3T3 cells. The expression of mutant MLCT18D,S19D (substitution of Thr and Ser by Asp), which is known to lead to the activation of myosin ATPase and a conformational change of myosin II when reconstituted with myosin heavy chains in vitro, also promoted neurite retraction.

Conclusion

These results indicate that Rho-kinase is involved in the LPA-induced neurite retraction downstream of Rho, and that myosin II activation promotes neurite retraction downstream of Rho and Rho-kinase.
  相似文献   
846.
Development of hepatocellular carcinomas in rats caused by a choline-deficient, L-amino acid-defined (CDAA) diet, usually associated with fatty liver, fibrosis, cirrhosis and oxidative DNA damage, has been recognized as a useful model of hepatocarcinogenesis caused by endogenous factors. In the present study, in order to further explore involved factors and genes, we established an equivalent model in spontaneous liver tumor-resistant C57BL/6J mice. Six-week-old males and females were continuously fed the CDAA diet and histological liver lesions and oxidative DNA damage due to 8-hydroxydeoxyguanosine (8-OHdG) were examined after 22, 65 and 84 weeks. In male mice, fatty change and fibrosis were evident at 22 weeks, and preneoplastic foci of altered hepatocytes were seen at an incidence of 8/8 (100%) and a multiplicity of 6.6 +/- 4.0 per mouse at 65 weeks. Hepatocellular adenomas and carcinomas developed at incidences of 16/24 (66.7%) and 5/24 (20.8%), and multiplicities of 1.42 +/- 1.32 and 0.29 +/- 0.62, respectively, at 84 weeks. The female mice exhibited resistance to development of these lesions. The CDAA diet also increased 8-OHdG levels in male but not female mice. These results indicate that a CDAA diet causes hepatocellular preneoplastic foci, adenomas and carcinomas associated with fibrosis and oxidative DNA damage in mice, as in rats, providing a hepatocarcinogenesis model caused by endogenous factors in mice.  相似文献   
847.
848.
A detailed procedure for simple and rapid analysis of acephate, an organophosphorous pesticide, and its metabolite methamidophos in human serum by gas chromatography-mass spectrometry was established. The method included solid-phase extraction with activated charcoal, which gave high recoveries of both analytes. After validation of the method, it was successfully applied to a serum sample obtained from an actual poisoning case. The present method seems very useful, especially in forensic and environmental toxicology.  相似文献   
849.
Background: Recently, quality as well as acceptability has been a concern regarding endoscopy. The aim of the present study was to compare the acceptability and quality of sedated high‐definition esophagogastroduodenoscopy (sHD‐EGD) using a newly developed high‐definition videoscope with those of unsedated ultrathin esophagogastroduodenoscopy (uUT‐EGD) using a 5.2 mm videoscope. Methods: Twenty‐two volunteers underwent both peroral sHD‐EGD and transnasal uUT‐EGD on the same day. Sedation consisted of 40 mg of propofol i.v. Both endoscopist and subject satisfaction levels were assessed using a 10 cm visual analogue scale. Results: All 22 subjects completed the sHD‐EGD and 21 subjects completed the uUT‐EGD. The endoscopist and subject satisfaction levels of sHD‐EGD were significantly better than those of uUT‐EGD (overall endoscopist satisfaction: 9 vs 4, P < 0.0001; overall subject satisfaction: 9 vs 3, P < 0.0001). The optical quality of the endoscopic images of sHD‐EGD was significantly higher than that of uUT‐EGD except in the duodenal bulb (overall quality: 8 vs 7, P < 0.0001). The interobserver agreement for EGD findings in sHD‐EGD was better than with uUT‐EGD, although the EGD findings in both sHD‐EGD and uUT‐EGD were similar. After undergoing both procedures, 91% were willing to have sHD‐EGD again compared to 9% with uUT‐EGD. Conclusions: The endoscopist and subject satisfaction levels and image quality of sHD‐EGD were better than those of uUT‐EGD. The routine use of high‐definition videoscopes would be expected to provide better acceptability than that obtained with unsedated endoscopy.  相似文献   
850.
Purpose: The aim of this study was to evaluate the microtensile bond strengths (MTBSs) of porcelain laminate veneers bonded to normal and fluorosed teeth.
Materials and Method: Forty human incisors, including 20 normal and 20 moderately fluorosed teeth [Thylstrup Fejerskov Index (TFI) = 4 to 6], were collected. The labial surfaces of the teeth were ground up to 1 mm and polished with #600 silicon carbide abrasive paper. The surfaces were bonded to 1-mm-thick ceramic slices (5 × 5 mm2) previously made (VitaVM7) using one of two ceramic cement systems (RelyX or Clapearl) following the manufacturers' instructions. A resin composite was added on top of the ceramic slices and built up to 5-mm thickness to serve as grips. The specimens were stored in water (37°C) for 24 hours, and beams of adhesive interface with a surface area of ∼1.25 mm2 were obtained. Then the beams were subjected to MTBS tests at a crosshead speed of 1.0 mm/min. The data were analyzed with two-way ANOVA.
Results: The results of the MTBS test (MPa) were 20.55 ± 5.83 (RelyX/fluorosed), 20.16 ± 4.61 (RelyX/normal), 18.74 ± 2.88 (Clapearl/fluorosed), and 21.06 ± 4.99 (Clapearl/normal). There were no significant differences in the MTBSs among the four groups ( p > 0.05).
Conclusions: The MTBSs of ceramic cement systems used were not influenced by the moderately fluorosed teeth.  相似文献   
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