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Mohammad Taherdangkoo Mohammad Hadi Bagheri Mehran Yazdi Katherine P. Andriole 《Journal of digital imaging》2013,26(6):1116-1123
Since segmentation of magnetic resonance images is one of the most important initial steps in brain magnetic resonance image processing, success in this part has a great influence on the quality of outcomes of subsequent steps. In the past few decades, numerous methods have been introduced for classification of such images, but typically they perform well only on a specific subset of images, do not generalize well to other image sets, and have poor computational performance. In this study, we provided a method for segmentation of magnetic resonance images of the brain that despite its simplicity has a high accuracy. We compare the performance of our proposed algorithm with similar evolutionary algorithms on a pixel-by-pixel basis. Our algorithm is tested across varying sets of magnetic resonance images and demonstrates high speed and accuracy. It should be noted that in initial steps, the algorithm is computationally intensive requiring a large number of calculations; however, in subsequent steps of the search process, the number is reduced with the segmentation focused only in the target area. 相似文献
43.
Different studies have shown the regulatory effects of vitamin D3 on the immune system and bone metabolism. Regarding the effects of vitamin D on immune cells and the importance of cytokines on bone metabolism, we assessed the association between serum levels of interleukin (IL)-6, IL-10, IL-12, IL-17 and IFN-γ cytokines and bone metabolism markers (Ca, P, PTH, ALP) in female students with vitamin D deficiency compared with control group. A total of 100 subjects with 25-hydroxy vitamin D3 (25-(OH) D3) deficiency were selected as case and 100 subjects with sufficient 25-hydroxy vitamin D3 (25-(OH) D3) were selected as the control group. The serum levels of IL-6, IL-10, IL-12, IL-17 and IFN-γ were measured by ELISA method. Ionized Ca, PTH, P, ALP levels were also determined in all participants. The results showed a statistically significant positive correlation between the levels of ALP with IFN-γ, PTH with IL-17 and a significant negative correlation between P with IL-10 in vitamin D deficient group. The results suggest that IL-17, IFN-γ and IL-10 are important mediators of bone metabolism and vitamin D affect bone metabolism, at least in part, through immune system. In addition, not only vitamin D affect bone metabolism but also modulates immune responses. 相似文献
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Strazzulla Alessio Postorino Maria Concetta Youbong Tracie Rouyer Maxence Flateau Clara Chakvetadze Catherine de Pontfarcy Astrid Pitsch Aurelia Jochmans Sebastien Belfeki Nabil Monchi Mehran Diamantis Sylvain 《European journal of clinical microbiology & infectious diseases》2021,40(7):1511-1516
European Journal of Clinical Microbiology & Infectious Diseases - This is a subanalysis of a previous study which compared the effectiveness of trimetoprim-sulfametoxazole (TMP-SMX) with all... 相似文献
45.
Nonalcoholic fatty liver disease (NAFLD) has emerged as the most common chronic liver cell damage worldwide. It is strongly associated with an increased risk of cardiovascular disease (CVD). There are not enough recommendations for screening subjects with nonalcoholic steatohepatitis cirrhosis, who are not candidates for liver transplantation, nor who are asymptomatic with NAFLD without cirrhosis. In the current comprehensive narrative review, we aimed to evaluate the associations between CVD and NAFLD. Distinguishing the mechanisms linking these two disorders offers the opportunity to develop targeted therapies. Moreover, we will discuss screening approaches (whom and how-to) and treatment modalities proposed to reduce cardiovascular risk in patients with NAFLD. 相似文献
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Mehran Anvari Craig A. Paterson Edwin E. Daniel Tom J. Mcdonald 《Digestive diseases and sciences》1998,43(6):1133-1140
Glucagon-like polypeptide 1 (GLP-1) may be amajor enterogastrone, slowing gastric emptying whenreleased by intestinal nutrients. In six conscious dogs,we studied the effects of GLP-1, on antropyloric motility, gastric emptying, and transpyloricflow after instillation of 500 ml of saline into thestomach. The meal was given and recordings were started15 min after intravenous bolus and infusion of either saline or three different doses of GLP-1.Intravenous GLP-1 produced a dose-related retardation ofgastric emptying associated with a decrease in thenumber and volume of flow pulses in comparison tosaline. This change in transpyloric flow was associatedwith an inhibition of antropyloric pressure waves, astimulation of isolated pyloric pressure waves, and anincrease in basal pyloric tone induced by intravenous GLP-1 infusion. Our findings show that GLP-1has a potent dose-dependent inhibitory effect ontranspyloric flow and gastric emptying. This effect istemporally associated with inhibition of antralpumping and stimulation of pyloricbraking mechanisms. 相似文献
50.
Vascular remodeling and plaque composition between focal and diffuse coronary lesions assessed by intravascular ultrasound 总被引:4,自引:0,他引:4
Fujii K Mintz GS Kobayashi Y Carlier SG Takebayashi H Jacoboff D Yasuda T Moussa I Dangas G Mehran R Lansky AJ Reyes A Kreps E Collins M Stone GW Leon MB Moses JW 《The American journal of cardiology》2004,94(8):1067-1070
Coronary remodeling and plaque composition were compared between focal and diffuse coronary lesions. Negative remodeling and fibrous and calcified plaque compositions contribute to stenosis development in diffuse lesions more frequently than in focal lesions. 相似文献