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991.
The usefulness of nanoscale topography in improving vascular response in vitro was established previously on hydrothermally modified titanium surfaces. To propose this strategy of surface modification for translation onto clinically used metallic stents, it is imperative that the surface should be also hemocompatible: an essential attribute for any blood-contacting device. The present in vitro study focuses on a detailed hemocompatibility evaluation of titania nanostructures created through an alkaline hydrothermal route on metallic Ti stent prototypes. Direct interactions of TiO2 nanocues of various morphologies with whole blood were studied under static conditions as well as using an in vitro circulation model mimicking arterial flow, with respect to a polished Ti control. Nanomodified stent surfaces upon contact with human blood showed negligible hemolysis under constant shear and static conditions. Coagulation profile testing indicated that surface roughness of nanomodified stents induced no alterations in the normal clotting times, with insignificant thrombus formation and minimal inflammatory reaction. Endothelialized nanomodified Ti surfaces were found to inhibit both activation as well as aggregation of platelets compared with the control surface, with the endothelium formed on the nanosurfaces having an increased expression of anti-thrombogenic genes. Such a nanotextured Ti surface, which is anti-thrombogenic and promotes endothelialization, would be a cost-effective alternative to drug-eluting stents or polymer-coated stents for overcoming in-stent restenosis.  相似文献   
992.
993.

Background  

Ergosterol peroxide (EP) derived from edible mushroom has been shown to exert anti-tumor activity in several cancer cells. In the present study, anti-angiogenic activity of EP was investigated with the underlying molecular mechanisms in human multiple myeloma U266 cells.  相似文献   
994.

Background  

Curcumin (diferuloylmethane), the yellow pigment in the Asian spice turmeric, is a hydrophobic polyphenol from the rhizome of Curcuma longa. Because of its chemopreventive and chemotherapeutic potential with no discernable side effects, it has become one of the major natural agents being developed for cancer therapy. Accumulating evidence suggests that curcumin induces cell death through activation of apoptotic pathways and inhibition of cell growth and proliferation. The mitotic checkpoint, or spindle assembly checkpoint (SAC), is the major cell cycle control mechanism to delay the onset of anaphase during mitosis. One of the key regulators of the SAC is the anaphase promoting complex/cyclosome (APC/C) which ubiquitinates cyclin B and securin and targets them for proteolysis. Because APC/C not only ensures cell cycle arrest upon spindle disruption but also promotes cell death in response to prolonged mitotic arrest, it has become an attractive drug target in cancer therapy.  相似文献   
995.
Rigid cognition is frequently cited as a plausible maintenance or risk factor for depression. However, most performance-based measures of cognitive rigidity associated with depression offer poor ecological validity, produce mixed findings, and afford little in the way of therapeutic application. In order to establish a more useful and relevant performance-based measure of cognitive rigidity in depression, we developed a novel task that probes a rigidity process using stimuli highly relevant to the level of construal, the thematic content, and the rhetorical mode of depressotypic thinking. The task consists of a set of narrative vignettes that contain an expectancy-violation that is incompatible with an initially-established interpretation. As hypothesized, depressive symptoms were associated with reduced ability to update interpretations. This finding was independent of the valence of the expectancy-violation (i.e., was not merely a negativity bias), and was significant after controlling for basic set-shifting ability, intelligence measures, working memory, and other potential confounds. The novel Contingent Inference Task is a promising approach that may probe a more ecologically and etiologically relevant form of cognitive rigidity in depression than other related performance-based rigidity tasks. This rigidity process may underlie the persistence of biased beliefs in depression, and represent a new therapeutic target.  相似文献   
996.
Conventional peer review practice is compromised by a number of well-documented biases, which in turn limit standard of care analysis, which is fundamental to determination of medical malpractice. In addition to these intrinsic biases, other existing deficiencies exist in current peer review including the lack of standardization, objectivity, retrospective practice, and automation. An alternative model to address these deficiencies would be one which is completely blinded to the peer reviewer, requires independent reporting from both parties, utilizes automated data mining techniques for neutral and objective report analysis, and provides data reconciliation for resolution of finding-specific report differences. If properly implemented, this peer review model could result in creation of a standardized referenceable peer review database which could further assist in customizable education, technology refinement, and implementation of real-time context and user-specific decision support.  相似文献   
997.
Blunt abdominal trauma mostly results from motor vehicle accidents, recreational accidents, falls or assaults with commonly injured internal organs being the spleen, liver, retroperitoneum, small bowel, kidneys, bladder, colorectal, diaphragm and pancreas. Gastric rupture is quite uncommon. Isolated gastric perforations following blunt trauma to the abdomen are mostly seen in paediatric patients. It is uncommon in adult patients and even rarer is the occurrence of double gastric perforations. We report here with a case of isolated double gastric perforation in a 24-year-old male patient following vehicular accident.  相似文献   
998.
999.
Reliability of Charcot’s triad has long been questioned. Tokyo Guidelines committee published Tokyo Guidelines in 2007 and 2013. The aim of this study was to retrospectively examine the patients who had been treated with the diagnosis of acute cholangitis and evaluate 2007–2013 Tokyo criteria and Charcot’s triad. The files of the patients with acute cholangitis in a referral center were examined retrospectively. All patients were classified and evaluated according to 2007 and 2013 Tokyo criteria and Charcot’s triad; and results were compared. It was detected that 51.7 % of patients who did not meet Charcot’s triad were in definitive diagnosis group of both Tokyo criteria. Kappa value was calculated as 0.404 in the analysis of consistency between two Tokyo criteria. Two patients who had features sufficient to objectively make the diagnosis of acute cholangitis failed to meet the Tokyo criteria 2007 or 2013. Charcot’s triad is not sensitive and specific enough in the diagnosis of acute cholangitis. Revision of Tokyo 2007 criteria caused a change in the diagnostic status of 15 % of the patients. It is remarkable that kappa value can hardly be considered as a sign of moderate agreement between two Tokyo guidelines. Tokyo criteria should be supported and updated.  相似文献   
1000.
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