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71.
Paredes A Alzuru M Mendez J Rodríguez-Ortega M 《Biological & pharmaceutical bulletin》2003,26(1):108-109
The effect of hesperetin, naringenin and its glycoside form on the Sindbis neurovirulent strain (NSV) replication in vitro was studied. All flavanones tested were not cytotoxic on Baby Hamster cells 21 clone 15 (BHK-21). Antiviral effect was evaluated by a colorimetric assay using MTT (3-(4,5 dimethylthiazol-2-yl)-2,5-dipheyl-tetrazolium bromide) and by plaque reduction assay. Hesperetin and naringenin had inhibitory activity on NSV infection. The 50% inhibitory doses (ID(50%)) of both compounds were 20.5 and 14.9 microg/ml respectively, as established by plaque assay. However their glycosides, hesperidin and naringin did not have inhibitory activity. Implying that the presence of rutinose moiety of flavanones blocks the antiviral effect. Oxygenation on the 3' positions at the B rings on the hesperetin skeleton decrease the anti viral activity at 25 microg/ml. 相似文献
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We report on some extensions and further developments of a well-known microcalcification detection algorithm based on adaptive noise equalization. Tissue equivalent phantom images with and without labeled microcalcifications were subjected to this algorithm, and analyses of results revealed some shortcomings in the approach. Particularly, it was observed that the method of estimating the width of distributions in the feature space was based on assumptions which resulted in the loss of similarity preservation characteristics. A modification involving a change of estimator statistic was made, and the modified approach was tested on the same phantom images. Other modifications for improving detectability such as downsampling and use of alternate local contrast filters were also tested. The results indicate that these modifications yield improvements in detectability, while extending the generality of the approach. Extensions to real mammograms and further directions of research are discussed. 相似文献
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Pituitary response to luteinizing hormone-releasing hormone analog at sea level and high altitudes 总被引:1,自引:0,他引:1
M Paredes Suarez J R Varea Teran G Garces C Avila D H Coy A V Schally 《Obstetrics and gynecology》1982,59(1):52-57
Two groups of subjects living at different altitudes were stimulated with synthetic luteinizing hormone-releasing hormone (LH-RH) or with an LH-RH analog. One hundred micrograms LH-RH was given subcutaneously to 19 men and 19 women, all normal, of reproductive age, and living at sea level, and to 19 men and 20 women living at a high altitude (2940 m). In neither sex, however, were the differences in peak responses for both gonadotropins significantly different between the sea level and high-altitude groups. Plasma levels of LH and follicle-stimulating hormone (FSH) were also measured after administration of [D-Leu6, des Gly-NH2(10)]-LH-RH ethylamide (25 micrograms subcutaneously) in 32 men and 37 women living at sea level and at high altitude. The analog induced a powerful and protracted stimulation of the release of LH and FSH irrespective of altitude and sex. The responses of men and women to the LH-RH analog, both for LH as well as for FSH, were significantly greater at sea level than at high altitudes. 相似文献
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Anghela Z. Paredes J. Madison Hyer Diamantis I. Tsilimigras Elizabeth Palmer Maryam B. Lustberg Mary E. Dillhoff Jordan M. Cloyd Allan Tsung Aslam Ejaz Sharla Wells-Di Gregorio Timothy M. Pawlik 《HPB : the official journal of the International Hepato Pancreato Biliary Association》2021,23(3):451-458
BackgroundAmong patients with pancreatic cancer, the association of pre-existing mental illness with long-term outcomes remains unknown.MethodsIndividuals diagnosed with pancreatic adenocarcinoma were identified in the SEER-Medicare database. Patients were classified as having mental illness if an ICD9/10CM code for anxiety, depression, bipolar disorder, schizophrenia or other psychotic disorder was recorded.ResultsAmong the 54,234 Medicare beneficiaries with pancreatic cancer, roughly 1 in 12 (n = 4793, 8.83%) individuals had a diagnosis of a mental illness. The majority (n = 4029, 84.1%) had anxiety or depression, while 16% (n = 764) had bipolar/schizophrenic disorders. On multivariable analysis, among patients with early stage cancer, individuals with pre-existing anxiety/depression and bipolar/schizophrenic disorders had 22% (OR 0.78, 95% CI 0.69–0.86) and 46% (OR 0.54, 95% CI 0.42–0.70) reduced odds, respectively, to undergo cancer-directed surgery. Furthermore, patients with a pre-existing history of bipolar/schizophrenic disorders had a 20% (HR 1.20, 95% CI 1.21–1.40) higher risk of all-cause mortality and 27% (HR 1.27, 95% CI 1.17–1.37) higher risk of pancreatic cancer-specific mortality compared to individuals without a history of mental illness.ConclusionOne in twelve patients with pancreatic cancer had a pre-existing mental illness. Individuals with mental illness were more likely to have worse overall and cancer-specific long-term outcomes. 相似文献
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