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Child Psychiatry & Human Development - Preschoolers’ emotional development typically hinges on the family emotional climate and their interactions with caregivers. This study used a...  相似文献   
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We pooled multiethnic data from four population-based studies and examined associations of menstrual and reproductive characteristics with breast cancer (BC) risk by tumor hormone receptor (HR) status [defined by estrogen receptor (ER) and progesterone receptor (PR)]. We estimated odds ratios and 95% confidence intervals using multivariable logistic regression, stratified by age (<50, ≥50 years) and ethnicity, for 5,186 HR+ (ER+ or PR+) cases, 1,365 HR− (ER− and PR−) cases and 7,480 controls. For HR+ BC, later menarche and earlier menopause were associated with lower risk in non-Hispanic whites (NHWs) and Hispanics, and higher parity and longer breast-feeding were associated with lower risk in Hispanics and Asian Americans, and suggestively in NHWs. Positive associations with later first full-term pregnancy (FTP), longer interval between menarche and first FTP and shorter time since last FTP were limited to younger Hispanics and Asian Americans. Except for nulliparity, reproductive characteristics were not associated with risk in African Americans. For HR− BC, lower risk was associated with later menarche, except in African Americans and older Asian Americans and with longer breast-feeding in Hispanics and Asian Americans only. In younger African Americans, HR− BC risk associated with higher parity (≥3 vs. 1 FTP) was increased fourfold in women who never breast-fed, but not in those with a breast-feeding history, suggesting that breast-feeding may mitigate the adverse effect of higher parity in younger African American women. Further work needs to evaluate why menstrual and reproductive risk factors vary in importance according to age and ethnicity.  相似文献   
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The objective of this study was to compare the accuracy for the diagnosis of appendicitis in patients presenting to the emergency department (ED) with acute, nontraumatic abdominal pain and a body mass index (BMI) of less than 25 before and after the implementation of a nonoral contrast computed tomography (CT) protocol with intravenous contrast. The IRB approved this HIPAA-compliant retrospective study; informed consent was waived. This study included 736 adult patients with a BMI of less than 25 presenting to our ED with acute, nontraumatic abdominal pain over two distinct 6-month time periods. An oral and intravenous contrast-enhanced protocol was utilized in the first cohort (group A), and an intravenous contrast-enhanced protocol without oral contrast was utilized in the second cohort (group B). Three abdominal fellowship-trained readers retrospectively reviewed all CT studies and electronic medical records, including surgical/pathology reports that served as reference standards. Group A consisted of 359 patients; 41 patients had surgically proven appendicitis. The sensitivity and specificity of the readers for diagnosing appendicitis in group A ranged from 95.2–100 and 98.1–99.5 %, respectively. Group B consisted of 372 patients; 39 had surgically proven appendicitis. The sensitivity and specificity of the readers in group B ranged from 92.0–100 and 98.6–100 %, respectively. There were no statistically significant differences in sensitivity or specificity for CT scans performed in groups A and B. In patients with a BMI of less than 25, an intravenous contrast-enhanced CT protocol without oral contrast demonstrates similar accuracy to an intravenous contrast-enhanced protocol with oral contrast for diagnosing acute appendicitis.  相似文献   
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