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排序方式: 共有178条查询结果,搜索用时 31 毫秒
131.
Anand K. Pyati Basavaraj B. Devaranavadagi Sanjeev L. Sajjannar Shashikant V. Nikam Mohd. Shannawaz Satish Patil 《Indian journal of clinical biochemistry : IJCB》2016,31(4):439-445
The study aimed to investigate whether heart-type fatty acid binding protein (H-FABP) measurement provides additional diagnostic value to that of conventional cardiac markers in acute myocardial infarction (AMI) within first 6 h after the onset of symptoms. The study included 120 subjects: 60 AMI cases and 60 age and sex matched controls. The cases and controls were further divided into 2 subgroups depending on the time since onset of chest pain as (1) subjects within 3 h and (2) between 3 and 6 h of onset of chest pain. In all the cases and controls, serum H-FABP concentration was measured by Immunoturbidimetric method, serum Troponin I and myoglobin concentrations by Chemiluminescence immunoassay and serum CK-MB concentration by Immuno-inhibition method. The sensitivity, specificity, positive and negative predictive values of H-FABP were significantly greater than CK-MB and myoglobin but were lesser than Troponin I in patients with suspected AMI in both within 3 h and 3–6 h groups. Receiver operating characteristic curves demonstrated greatest diagnostic ability for Troponin I (AUC = 0.99, p < 0.001) followed by H-FABP (AUC = 0.906, p < 0.001) within 3 h and 3–6 h after the onset of chest pain. In conclusion, the diagnostic value of H-FABP is greater than CK-MB and myoglobin but slightly lesser than troponin I for the early diagnosis of AMI within first 6 h of chest pain. H-FABP can be used as an additional diagnostic tool for the early diagnosis of AMI along with troponin I. 相似文献
132.
Yuval Noah Harari 《中学历史教学参考》2021,(6):1-1
在7万年前,智人还不过是一种微不足道的动物,在非洲的角落自顾自地生活。但就在接下来的几千年间,智人就成了整个地球的主人、生态系统的梦魇。时至今日,智人似乎只要再跨一步就能进入神的境界,不仅有望获得永恒的青春,更拥有创造和毁灭一切的神力。但遗憾的是,智人在地球上的所作所为,实在没有太多令人自豪。 相似文献
133.
We present a microfluidic technique that generates asymmetric giant unilamellar vesicles (GUVs) in the size range of 2–14 μm. In our method, we (i) create water-in-oil emulsions as the precursors to build synthetic vesicles, (ii) deflect the emulsions across two oil streams containing different phospholipids at high throughput to establish an asymmetric architecture in the lipid bilayer membranes, and (iii) direct the water-in-oil emulsions across the oil–water interface of an oscillating oil jet in a co-flowing confined geometry to encapsulate the inner aqueous phase inside a lipid bilayer and complete the fabrication of GUVs. In the first step, we utilize a flow-focusing geometry with precisely controlled pneumatic pressures to form monodisperse water-in-oil emulsions. We observed different regimes in forming water-in-oil multiphase flows by changing the applied pressures and discovered a hysteretic behavior in jet breakup and droplet generation. In the second step of GUV fabrication, an oil stream containing phospholipids carries the emulsions into a separation region where we steer the emulsions across two parallel oil streams using active dielectrophoretic and pinched-flow fractionation separations. We explore the effect of applied DC voltage magnitude and carrier oil stream flow rate on the separation efficiency. We develop an image processing code that measures the degree of mixing between the two oil streams as the water-in-oil emulsions travel across them under dielectrophoretic steering to find the ideal operational conditions. Finally, we utilize an oscillating co-flowing jet to complete the formation of asymmetric giant unilamellar vesicles and transfer them to an aqueous phase. We investigate the effect of flow rates on properties of the co-flowing jet oscillating in the whipping mode (i.e., wavelength and amplitude) and define the phase diagram for the oil-in-water jet. Assays used to probe the lipid bilayer membrane of fabricated GUVs showed that membranes were unilamellar, minimal residual oil remained trapped between the two lipid leaflets, and 83% asymmetry was achieved across the lipid bilayers of GUVs. 相似文献
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Michael P. Dunne Adam J. Zolotor Desmond K. Runyan Inna Andreva-Miller Wan Yuen Choo Simon K. Dunne Bernard Gerbaka Oksana Isaeva Dipty Jain Mohd Sham Kasim Bonnie Macfarlane Nurgul Mamyrova Clemencia Ramirez Elena Volkova Randa Youssef 《Child abuse & neglect》2009,33(11):815-825
ObjectivesTo gain consensus among an ethnically and linguistically diverse group of international child protection experts on the structure and content of a new survey tool for retrospective measurement of child abuse, and to determine the performance of the instrument through an international field trial with young adults.MethodsThe questionnaire was developed through focus group discussions with international experts, and then subjected to a Delphi study in two waves to determine the perceived importance and translatability of items. The resultant questionnaire was translated into six languages and field tested in seven countries with convenient samples of young adults aged 18–26 years (N = 842).ResultsChild maltreatment experts from 28 countries provided input to questionnaire development. Satisfactory agreement on draft item inclusion and exclusion and the translatability of items was gained. The tool includes 15 primary questions about potentially abusive physical, sexual and emotional events, with follow-up questions about perpetrator characteristics, frequency of acts and periods in childhood when the recalled abuse occurred. The field test revealed lifetime prevalence per item usually exceeded 10% (11/15 items; range 2.1–49.5%). Internal consistency (Cronbach's alpha) was moderate to high for each of three item sub-sets (between .61 and .82) and the rates of missing data were low (less than 1.5% for 14 of 15 items). The great majority of respondents nominated either peer and/or adult perpetrators (between 82.3% and 98.2% depending upon the item), and among these, child/adolescent peers and non-family adults (including teachers for emotional and physical acts) were nominated often.ConclusionsThe ICAST-R is based on consensus from international experts, translates clearly and has satisfactory properties for adoption as a survey tool to estimate prevalence and describe perpetrators and other contextual aspects of child abuse.Practice implicationsThis tool can be utilized in a broad range of cultures and languages and may contribute to improved research practice. Although the core items are limited to just 15 acts of maltreatment, if these behaviorally specific questions are adopted as key indicators and incorporated into comprehensive local, national or regional surveys, eventually there should be greater comparability in survey estimates. 相似文献
136.
Hussain Mumtaz Sahudin Shariza Fauzi Syahirah Mohd Manaf Nurshahirah Abdul Wahab Mohd Shahezwan Abd 《Higher Education》2021,81(6):1257-1272
Higher Education - There are many factors that motivate students to choose a particular academic major, whether it is due to interest, salary, or family. Government policies and... 相似文献
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138.
Noah Arceneaux 《广播与电子媒介杂志》2018,62(3):531-546
QUBE was an interactive cable television system that attracted significant attention when it launched in 1977. The service has been deemed a commercial failure, though many of its ideas foreshadowed current television practices. There is however no detailed study of QUBE, and previous scholarship provides limited information. Using Moran’s concept of an “evolution-revolution,” this study analyzes the content offerings of QUBE to reveal how they were similar, and how they differed, from prior practice. This historical inquiry fills a gap in the historical record, while also exploring the complex nature of innovation in the world of electronic media. 相似文献
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140.
Choshi Kasanda Noah Gaoseb Utji Kandjeo‐Marenga Hileni Kapenda Bob Campbell 《International Journal of Science Education》2013,35(15):1805-1823
This paper reports on the use of out‐of‐school everyday contexts in Namibian science classrooms. This use is portrayed against the backdrop of an explicit educational philosophy of learner‐centred teaching. Data were collected through audio‐taped teacher–learner interactions and non‐participant field notes in 29 junior and senior science classes taught by 12 teachers in six schools. An existing typology was applied to classify episodes of use of everyday contexts and identify teachers’ pedagogic strategies for their use. The results show that more everyday contexts are used in junior secondary than in senior secondary classes, that only a limited range of types of everyday contexts are used at both levels, and that their use often follows theoretical exposition or teacher questioning. These findings are related to three interpretations of learner‐centred teaching. Recommendations for a fuller implementation of learner‐centred teaching are made. 相似文献