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Jie Zhang PhD Long Sun MA Yuxin Liu PhD Jianwei Zhang PhD 《Suicide & life-threatening behavior》2014,44(5):560-568
Chinese suicide rates have been reported in various studies in the past two decades, but few of them were based on national data. The most recent mortality data (2002–2011) provided by the China Ministry of Health and the detailed census data provided by the National Population Census were used in this study. We calculated the age‐, gender‐, and region‐specific suicide rates and their trends in the past 10 years between 2002 and 2011. The overall suicide rates in China decreased during the study period. The rural/urban ratio of the suicide rates has been significantly reduced from the ratio in the 1990s, and male suicide rates have exceeded those of females. Age was positively associated with suicide rates without the two peaks found in the suicide rates over 20 years ago. The Chinese suicide rates have significantly declined in the past decade, with withering of the unique suicide rate patterns previously found in Chinese suicides about 20 years ago. 相似文献
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Jeffrey Long 《Journal of Near-Death Studies》2003,21(3):191-194
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The contrast sensitivity functions of a large group of observers (N = 71) were determined for three orientations of test gratings: vertical, oblique, and horizontal. Comparison of group means indicated that, consistent with previous findings for the 'oblique effect', sensitivity was poorer for the oblique orientation-but only for the mid-high spatial frequencies. Correlation analyses indicated that contrast sensitivity for a particular spatial frequency at a given orientation was highly correlated with contrast sensitivity for that same frequency at the other two orientations. Factor analysis of the intercorrelations revealed two strong factors, a low frequency factor, and a mid-high frequency factor. Results are discussed in terms of: (a) the implications for contrast-sensitivity testing across orientations, (b) the basis for the oblique effect, and (c) a different type of evidence for a dichotomy among spatial-frequency channels that may reflect the distinction between X cells and Y cells or between the parvocellular and magnocellular systems. 相似文献