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991.
We report a rapid, low-cost, portable microfluidic sedimentation cytometer (SeCy) for assessing the somatic cell count and fat content of milk in 15 min using a “sample-in, answer-out” approach. The system consists of 12 independent microfluidic devices, essentially flattened funnel structures, fabricated on the footprint of a single plastic compact disc (CD). Each funnel structure holds 150 μL of milk, has an inlet for milk filling and an outlet for air to escape, and ends in a narrow, closed-end microfluidic channel that facilitates packing of the cells into a column whose length is proportional to cell count. The closed-end channel provides accurate cell counts over the range 50,000–>3,000,000 cells per mL. The assay separates cells and fat globules based on their densities (by differential sedimentation), concentrating white cells in the closed-end channel near the outer rim of the CD for estimation of total “cell pellet” volume, while fat globules move toward the center of disc rotation, forming a fat “band” in the funnel. After adding milk to two or more microfluidic devices, the CD is loaded onto a custom-built reader unit that spins the disc for 15 min. Two low-cost microscopes in the reader image the centrifuged cell pellet and the fat band, providing a sufficiently accurate cell count to diagnose mastitis and measuring fat content as an indication of health and nutritional status.  相似文献   
992.
Little is known about the factorial invariance across gender and age for self-report measures of social anxiety in adolescence. This study examined the factorial invariance and latent mean differences of the Social Anxiety Scale for Adolescents (SAS-A) across gender and age groups in 1570 Spanish adolescents (54% girls), ranging in age from 14 to 17 years. Equality of factor structures was compared using multi-group confirmatory factor analyses. Measurement invariance for the correlated three-factor model of the SAS-A was found across gender and age samples. Analyses of latent mean differences revealed that girls exhibited higher means than boys on two SAS-A subscales, Fear of Negative Evaluation and Social Avoidance and Distress-New (SAD-New). In addition, on the SAD-New subscale, the structured means significantly diminished from 14-year olds to 16- and 17-year olds and from 15-year olds to 17-year olds. Findings are discussed in terms of the use of the SAS-A with Spanish adolescents.  相似文献   
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Purpose  

To analyze the evolution of hemodynamic, respiratory, and tissue perfusion parameters in an infant animal model of asphyxial cardiac arrest (CA).  相似文献   
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The solid fibrous solitary tumour of the oral cavity is an extremely rare entity. It is also of complicated diagnosis because of its extensive morphologic diversity (especially when there is a small amount of biopsied tissue) and because of its similarity to many mesenchymal injuries, mostly with hemangiopericytoma. The prognosis is reserved because of the few cases reported, mainly depending on tumour location and size.  相似文献   
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CRANIum, a cross-sectional epidemiology study in Western Europe and Canada, was conducted to describe and compare the prevalence of a positive screen for neurocognitive impairment (NCI), depressive symptoms, and anxiety in an HIV-positive population either receiving combination antiretroviral therapy (cART) or who were naive to antiretroviral therapy (ART). HIV-positive patients ≥18 years of age attending a routine medical follow-up visit and able to complete the designated screening tools were eligible for study inclusion. The Brief Neurocognitive Screen was used to assess NCI; depressive and anxiety symptoms were assessed using the Hospital Anxiety and Depression Scale. The evaluable patient population (N = 2863) included 1766 men (61.7%) and 1096 (38.3%) women. A total of 1969 patients were cART-experienced (68.8%), and 894 were ART-naive (31.2%). A positive screen for NCI was found in 41.5% of patients (cART-experienced, 42.5%; ART-naive, 39.4%; p = 0.12). A positive screen for depressive symptoms was found in 15.7% of patients (cART-experienced, 16.8%; ART-naive, 13.3%; p = 0.01), whereas 33.3% of patients screened positive for anxiety (cART-experienced, 33.5%; ART-naive, 32.8%; p = 0.71). A greater percentage of women compared with men screened positive for NCI (51.78% vs. 35.1%; p < 0.0001) and depressive symptoms (17.9% vs. 14.3%; p = 0.01). These data suggest that neurocognitive and mood disorders remain highly prevalent in HIV-infected patients. Regular mental health screening in this population is warranted.  相似文献   
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