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991.
Ayami Ohno Kishimoto Masako Kataoka Mami Iima Maya Honda Kanae Kawai Miyake Akane Ohashi Rie Ota Tatsuki Kataoka Takaki Sakurai Masakazu Toi Kaori Togashi 《Magnetic resonance in medical sciences》2021,20(2):204
Purpose:We aimed to investigate the performance of high resolution-diffusion-weighted imaging (HR-DWI) using readout-segmented echo-planar imaging in visualizing malignant breast lesions and evaluating their extent, using pathology as a reference.Methods:This retrospective study included patients who underwent HR-DWI with surgically confirmed malignant breast lesions. Two radiologists blinded to the final diagnosis evaluated HR-DWI independently and identified the lesions, measuring their maximum diameters. Another radiologist confirmed if those lesions were identical to the pathology. The maximum diameters of the lesions between HR-DWI and pathology were compared, and their correlations were calculated using Spearman’s correlation coefficient. Apparent diffusion coefficient (ADC) values of the lesions were measured.Results:Ninety-five mass/64 non-mass lesions were pathologically confirmed in 104 females. Both radiologists detected the same 93 mass lesions (97.9%). Spearman’s correlation coefficient for mass lesions were 0.89 and 0.90 (P < 0.0001 and 0001) for the two radiologists, respectively. The size differences within 10 mm were 90.3% (84/93) and 94.6% (88/93) respectively. One radiologist detected 35 non-mass lesions (54.7%) and another radiologist detected 32 non-mass lesions (50.0%), of which 28 lesions were confirmed as identical. Spearman’s correlation coefficient for non-mass lesions were 0.59 and 0.22 (P = 0.0002 and 0.22), respectively. The mean ADC value of mass lesions and non-mass lesions were 0.80 and 0.89 × 10−3 mm2/s, respectively.Conclusion:Using HR-DWI, malignant mass lesions were depicted with excellent agreement with the pathological evaluation. Approximately half of the non-mass lesions could not be identified, suggesting a current limitation of HR-DWI. 相似文献
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PurposeLumbar spondylolysis in children of elementary school age has different characteristics from those of junior or senior high school patients. The purpose of the present study was to investigate the outcomes of conservative treatment for lumbar spondylolysis in patients of elementary school age.MethodsWe included 46 lesions in 32 consecutive patients of elementary school age with fresh cases of lumbar spondylolysis (5 girls and 27 boys; mean age, 11.3 years). We examined the relationship between bone union after conservative treatment and factors such as the CT axial staging, whether the lesion was unilateral or bilateral, whether the contralateral lesion was terminal stage, and the presence of spina bifida occulta.ResultsBone union was achieved in 33 lesions (72%) in 23 patients, whereas 13 lesions (28%) in 9 patients could not obtain bone union. The proportion of unilateral lesions with bone union was 13 of 13 (100%), significantly higher than that for bilateral lesions (20/33 lesions, 61%, p = 0.009). Of the 33 bilateral lesions, bone union was attained in 20 of 28 (71%) lesions without contralateral terminal stage, whereas bone union was not attained in any of 5 (0%) lesions with contralateral terminal stage, showing a significant difference between those with or without contralateral terminal stage (p = 0.005).ConclusionBilateral lesions and contralateral terminal stage are possible unfavorable factors to bone union in conservative treatment for patients of elementary school age with lumbar spondylolysis. Early diagnosis and treatment before the lesions become bilateral or progressive stage are important. 相似文献
994.
《Sleep medicine》2021
BackgroundDelayed sleep–wake phase disorder (DSWPD) during adolescence has been linked to impaired health and poor functioning. However there is a dearth of knowledge about DSWPD in young adulthood. We seek to contribute knowledge on the prevalence and correlates of DSWPD in this age group.MethodsData were drawn from a 2018 national survey of students in higher education in Norway (the SHoT-study). All 162,512 fulltime students in Norway were invited to participate and 50,054 students (69.1% women) aged 18–35 years were included (response rate = 30.8%). DSWPD was assessed by self-report, and was operationalized according to the criteria for DSWPD in the most recent edition of the International Classification of Sleep Disorders. Correlates of DSWPD were examined by validated self-report instruments covering a wide range of demographic and health domains.ResultsThe overall prevalence of DSWPD was 3.3%, and significantly higher in male (4.7%) than female (2.7%) students. DSWPD was associated with being single, having financial difficulties, having divorced parents, being overweight/obese, and physical inactivity. Students with DSWPD had more sleep problems during weekdays, and higher levels of somatic and mental health problems. Students with DSWPD also had an elevated risk of self-harm-related thoughts and behaviors as well as suicidality.ConclusionDSWPD remains a significant problem among young adults, and the high symptom load across health domains indicates that suggests a need for existing evidence-based approaches to be scaled for college students who present with DSWPD. 相似文献
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Irina Butnaru Maria Bruma Thomas Kopnick Joachim Stumpe 《Macromolecular chemistry and physics.》2013,214(21):2454-2464
The influence of different substituents on the optical properties of poly(amide imide)s and polyimides is systematically investigated. All of the polymers exhibit good solubility and film‐forming ability, high thermal stability, and glass transition temperatures of 162–209 °C for poly(amide imide)s and of 209–274 °C for polyimides. The optical transmittance of the films at 450 nm is above 80% for all the studied polyimides and poly(amide imide)s containing benzonitrile units linked in the 2,6‐position. The values of refractive index for poly(amide imide)s are in the range of 1.623–1.748 and for polyimides in the domain of 1.672–1.768.