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Visual tasks that involve judging distance or depth obviously benefit from considering retinal disparities and ocular convergence, but various simple visual thresholds are also lower when looking with two eyes. This is also true for stereo-blind subjects. One benefit of using two eyes is that looking with two eyes provides two chances of making the critical distinction. From the literature it would appear that using two eyes might only be an advantage for low contrast stimuli and simple tasks. We here demonstrate that stereo-blind subjects can benefit from using two eyes when making judgments about clearly visible complex stimuli. The task was to judge the direction of rotation of a simulated transparent cylinder. Stereo-blind subjects performed better when looking with two eyes than when looking with their preferred eye. It did not matter for their performance whether the images in their two eyes were correlated or not. Various control experiments ascertained that they judged the direction of rotation from the images in each eye separately and then combined these judgments, rather than relying on differences between the images in the two eyes. These findings raise doubts about the validity of using monocular vision as a control for quantitative studies of the use of binocular disparity.  相似文献   
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A Tale of Two Brothers: Anomalous Coronary Arteries in Two Siblings   总被引:1,自引:1,他引:0  
We report a case of a 10-year-old boy with aberrant left coronary artery from the right sinus of Valsalva, whose presenting sign was cardiac arrest. The patient's asymptomatic younger brother was found to have aberrant right coronary artery from the left sinus of Valsalva. This is the first report of a familial clustering of coronary artery anomalies in which the initial presentation of one subject was sudden cardiac death and a sibling harboring a similar lesion was identified while asymptomatic.  相似文献   
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Increasing evidence shows physical activity to be associated with improved colorectal cancer (CRC) prognosis. However, large‐scale prospective patient cohorts, comprehensively ascertaining physical activity, comprehensively considering potential variation by CRC stage and considering specific outcome measures, are sparse. Therefore, we aimed to evaluate the association of lifetime and latest prediagnostic leisure time physical activity with relevant prognostic outcomes in a large population‐based cohort of CRC patients. 3,121 patients, diagnosed with CRC in 2003–2010 (median age: 69 years), were interviewed on sociodemographic and lifestyle factors, medication and comorbidities. Cancer recurrence, vital status and cause of death were documented over a median follow‐up time of 4.8 years. Associations between lifetime and latest prediagnostic leisure time physical activity and overall, CRC‐specific, recurrence‐free and disease‐free survival were evaluated with Cox regression. Latest but not lifetime leisure time physical activity [in metabolic task hours per week (MET‐h/wk)] was associated with decreased overall and CRC‐specific mortality (>56.2 vs. ≤13.2 MET‐h/wk: adjusted hazard ratio (aHR)Overall/latest = 0.75; 95% confidence interval (CI) = 0.61–0.91; aHRCRC‐specific/latest = 0.81; 95% CI = 0.64–1.02). In particular lifetime and latest walking were associated with decreased mortality (>20 vs. 0–10 MET‐h/wk of walking: aHROverall/latest = 0.66; 95% CI = 0.56–0.77; aHRCRC‐specific/latest = 0.72; 95% CI = 0.60–0.87; aHROverall/lifetime = 0.78; 95% CI = 0.66–0.93; aHRCRC‐specific/lifetime = 0.71; 95% CI = 0.58–0.86). Associations were particularly pronounced for lifetime walking in metastatic (stage IV) and for latest walking in nonmetastatic disease patients. Prediagnostic physical activity was associated with improved CRC prognosis. Associations might be restricted to certain activities or depend on (non)metastatic disease state. Further optimization of activity recommendations and increase of recommendation adherence may help to improve patients' prognosis.  相似文献   
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Fecal immunochemical tests (FITs) for hemoglobin are increasingly recommended and used in colorectal cancer (CRC) screening. We aimed to provide a detailed assessment of the sensitivity of FIT according to type and subsite of neoplasms in a true screening setting. A quantitative FIT (FOB Gold, Sentinel Diagnostics, Milano, Italy) was applied prior to colonoscopy by 3,466 participants of the German screening colonoscopy program. Subsite specific sensitivity for various types of colorectal neoplasms was derived by comparing FIT results with findings at screening colonoscopy. The most advanced finding at colonoscopy was CRC, advanced adenoma, and nonadvanced adenoma in 29, 354 and 686 cases, respectively. Per‐adenoma sensitivity for large advanced adenomas (>1 cm) strongly varied by location (p < 0.001): cecum: 0/14 (0%), ascending colon and right flexure: 11/43 (26%), transverse colon and left flexure: 2/14 (14%), descending colon: 7/12 (58%), sigmoid colon: 47/92 (51%), rectum: 14/39 (36%). By contrast, the FIT detected all of 5 proximal CRC and 23 out of 24 (96%) distal CRCs, whereas per‐adenoma sensitivity of both proximal (17/259, 7%) and distal nonadvanced adenomas (20/237, 8%) essentially equaled the false positivity rate among those without neoplasms (152/2,397, 6%). In conclusion, we found a very large gradient of subsite specific FIT sensitivity for detecting large advanced adenomas ranging from 0% for advanced adenomas located in the cecum to >50% for those located in the descending or sigmoid colon. By contrast, FIT sensitivity was uniformly excellent for CRC and uniformly poor for nonadvanced adenomas, regardless of their location.  相似文献   
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To evaluate risk of thyroid neoplasia nearly 30 years following exposure to radioactive iodine (I‐131) from the 1986 Chernobyl nuclear accident, we conducted a fifth cycle of thyroid screening of the Ukrainian‐American cohort during 2012–2015, following four previous screening cycles started in 1998. We identified 47 thyroid cancers (TC) and 33 follicular adenomas (FA) among 10,073 individuals who were <18 years at the time of the accident and had a mean I‐131 dose of 0.62 Gy. We found a significant I‐131 dose response for both TC and FA, with an excess odd ratio per Gy of 1.36 (95% CI: 0.39–4.15) and 2.03 (95% CI: 0.55–6.69), respectively. The excess risk of malignant and benign thyroid neoplasia persists nearly three decades after exposure and underscores the importance of continued follow‐up of this cohort to characterize long‐term pattern of I‐131 risk.  相似文献   
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