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To report the clinical characteristics and visual outcomes of patients with keratoconus treated with posterior chamber phakic intraocular lenses after implantation of intracorneal ring segments (ICRS). This retrospective study included 11 eyes of eight patients diagnosed with keratoconus treated with ICRS and posterior chamber phakic intraocular lenses. The preoperative and postoperative uncorrected distance visual acuity (UDVA), corrected distance visual acuity (CDVA), preoperative and postoperative keratometric data, manifest refraction and spherical equivalent were recorded. No complications were observed. At 38.18?±?18.7?months of follow-up, the mean spherical error was -0.06?±?0.46 D (+0.75 to -0.75 D) and cylindrical error of -1.22?±?0.65 D (-0.25 to -1.5 D). The preoperative spherical equivalent was -10.52?±?5.88 D (-3.12 to -22.75 D) and the postoperative spherical equivalent was -0.68?±?0.45 D (0 to -1.25 D), p?相似文献   
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SN Yeung  A Lichtinger  P Kim  MD Amiran  AR Slomovic 《Cornea》2012,31(10):1214-1215
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Balancing energy and nitrogen in the rumen is a key to both profitability and environmental sustainability. Four dairy cows were used in a Latin square experimental design to investigate the effect of severe nitrogen underfeeding (110 vs. 80% of requirements) and the type of carbohydrate consumed [neutral detergent fiber rich (FIB) vs. starch rich (STA)] on the rumen ecosystem. These dietary treatments modified both rumen fermentation and microbial populations. Compared with STA diets, consumption of FIB diets increased bacterial and fungal diversity in the rumen and also increased the concentrations of cellulolytic microorganisms, including protozoa (+38%), anaerobic fungi (+59%), and methanogens (+27%). This microbial adaptation to fiber utilization led to similar digestibility values for the 2 carbohydrate sources and was accompanied by a shift in the rumen fermentation patterns; when the FIB diets were consumed, the cows had greater ruminal pH, ammonia concentrations, and molar proportions of acetate and propionate compared with when they consumed the STA diets. Certain rumen microorganisms were sensitive to a shortage of nitrogen; rumen concentrations of ammonia were 49% lower when the low-protein (LP) diets were consumed as were total bacteria (-13%), anaerobic fungi (-28%), methanogens (-27%), protozoa (-19%), cellulolytic bacteria, and microbial diversity compared with when the high-protein (HP) diets were consumed. As a result, the digestibility of the LP diets was less than that of the HP diets. These findings demonstrated that the rumen microbial ecosystem is directly linked to the rumen fermentation pattern and, to some extent, to the efficiency of diet utilization by dairy cattle.  相似文献   
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This study evaluated the validity of self-reported weight and height for determining nutritional status and the implications of their use for analyzing associations with health outcomes. A population-based cross-sectional study in Pelotas, Rio Grande do Sul State, Brazil, in 2007 (n = 2,986) drew a sub-sample of 276 individuals aged ≥ 20 years. Mean self-reported weight was similar to measured weight; height was overestimated in men (1.4 cm) and women (2.5 cm); real body mass index (BMI) was underestimated by about 1 kg/m(2). Even with small mean differences, data variability was great. The results were influenced by gender, age, and schooling. The use of self-reported measures underestimated prevalence of overweight and obesity, and unpredictable errors were found in the analysis of association with health outcomes (underestimation, overestimation, and reversal of real effect measures). Correction equations reduced the mean differences but did not resolve variability of the differences, classification errors, or biases in the associations.  相似文献   
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