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31.
Just noticeable differences (JNDs) in orientation for real lines and illusory contours were compared. JNDs in orientation of an illusory contour and of a real line differ by less than a factor two. JNDs in orientation of an illusory contour showed meridional variations similar to those obtained for a real line. By scaling measurements illusory contours are equally visible at all orientations, so meridional variations in illusory orientation discrimination reflect an anisotropy in orientation processing mechanisms. JNDs in orientation measured at an oblique reference orientation improve with practice for an illusory contour as well as for a real line. However while the effect of practice transfers from an illusory to a real contour, the reverse is not true. These results suggest that there are two paths for processing orientation: one activated only by real lines, the other concerned with both real and illusory contours. 相似文献
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Three‐dimensional speckle tracking echocardiography–derived left atrial deformation analysis in acromegaly (Results from the MAGYAR‐Path Study) 下载免费PDF全文
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The effects of androgens and the androgen antagonist, flutamide, on the density of dendritic spine synapses in the CA1 subfield of the hippocampus were studied in gonadectomized male and female rats. Treatment of orchidectomized male rats with dehydroepiandrosterone (DHEA; 2 d, 1 mg/d sc) increased the density of CA1 spine synapses observed 2 d later, by 106%, without significantly affecting ventral prostate weight. The hippocampal response to DHEA was unaffected by blockade of intracerebral estrogen biosynthesis using the aromatase inhibitor, letrozole. By contrast, flutamide alone (2 d; 5 mg/d, sc) increased CA1 spine synapse density by 66%, whereas in combination the effects of flutamide and DHEA were additive rather than inhibitory. Additive effects on CA1 synapse density were also observed in males using combinations of flutamide with 5alpha-dihydrotestosterone (2 d, 500 microg/d, sc). At the same doses, flutamide had no effect on prostate weight and completely blocked the effects on the prostate of treatment with 5alpha-dihydrotestosterone. Treatment of ovariectomized females with DHEA increased CA1 spine synapse density to a level similar to that observed in the male. As in males, flutamide in females increased CA1 spine synapse formation and further augmented the response to DHEA. These results demonstrate that flutamide and DHEA have positive effects on hippocampal CA1 spine synapse density in both sexes. They also suggest that conventional measures of androgen agonist or antagonist activity, exemplified by ventral prostate growth, may not be indicative of effects on hippocampal CA1 synaptogenesis. 相似文献
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Impact of single nucleotide polymorphisms of cytarabine metabolic genes on drug toxicity in childhood acute lymphoblastic leukemia 下载免费PDF全文
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Melissa Soohoo Elani Streja Yoshitsugu Obi Connie M. Rhee Daniel L. Gillen Keiichi Sumida Danh V. Nguyen Csaba P. Kovesdy Kamyar Kalantar-Zadeh 《Mayo Clinic proceedings. Mayo Clinic》2018,93(8):1074-1085
Objective
To determine whether kidney function level and its rate of decline in the immediate predialysis period among veterans transitioning to end-stage renal disease (ESRD) predict postdialysis mortality and hospitalization.Patients and Methods
In 19,985 veterans transitioning to ESRD during the period October 1, 2007, to March 30, 2014, we examined kidney function and its slope over the final year of the pre-ESRD(prelude) period. Two categories of low vs high estimated glomerular filtration rate (eGFR, dichotomized at 10 mL/min/1.73 m2) and slow vs fast slope (dichotomized at ?10 mL/min/1.73 m2/y) were combined into 4 groups. Their associations with 12-month post-ESRD all-cause and cardiovascular (CV) mortality and hospitalization rates were examined in adjusted models accounting for clinical characteristics and laboratory measurements at transition.Results
Patients, 66±11 years old, and 34% blacks, had a median (interquartile range) eGFR at transition and slope of 9.7 (7.1-13.3) mL/min/1.73 m2 and ?10.5 (?18.8 to ?5.9) mL/min/1.73 m2/y, respectively. Patients with a low eGFR and slow slope had the lowest 12-month all-cause and CV mortality risks and hospitalization rate. Conversely, patients with high eGFR and fast slope had the highest risk of all-cause and CV mortality and hospitalization rate compared with patients with a low eGFR and slow slope. This relationship persisted in sensitivity analyses, including propensity scoring.Conclusion
A kidney profile of a low eGFR and slow slope in the prelude period is associated with favorable early dialysis outcomes in veteran patients. Trials to examine a more conservative approach to dialysis are warranted. 相似文献40.
Zsóka Weiszhár András Bikov Gabriella Gálffy Lilla Tamási Ildikó Ungvári Csaba Szalai György Losonczy Ildikó Horváth 《Journal of clinical immunology》2013,33(2):496-505