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101.
The purpose of this study was to document the design, classroom implementation, and effectiveness of interactive online units to enhance science learning over 3 years among students with learning disabilities, English learners, and general education students. Results of a randomised controlled trial with 2,303 middle school students and 71 teachers across 13 schools in two states indicated that online units effectively deepened science knowledge across all three student groups. Comparing all treatment and control students on pretest-to-posttest improvement on standards-based content-specific assessments, there were statistically significant mean differences (17% improvement treatment vs. 6% control; p?相似文献   
102.
This paper proposes a model to assess the level of maturity in Virtual Communities of Practice (VCoPs). The model is based on a theoretical construction attained from the analysis of previous frameworks proposed in literature. Using this construction, we have proposed eight main organizational, managerial and technological levers to improve the performance of VCoPs. Additionally, the model presents the analysis of four performance metrics obtained from these VCoP management levers. The model presented can be used as a benchmarking tool for analysing how companies perform in their management of VCoPs. After developing the model, we applied it to a benchmarking study of four global oil and gas companies. Our results include a performance comparison among these companies as well as the main practices and technologies they use to achieve success in the management of VCoP.  相似文献   
103.
The internalization of apoptotic cells by non-phagocytic cells has been observed in different tissues and could be an important mechanism for the elimination of dying cells. Here, we describe a probable event of phagocytosis of apoptotic cells mediated by urothelial cells in urinary sediment. A 90-years-old male patient was admitted unconscious to the hospital, visible signs included: pale skin and dry mucous membranes, presumptively diagnosed as dehydration. Blood test revealed anaemia (haemoglobin 130 g/L) and hyperglycaemia (glucose 7.8 mmol/L), urinalysis showed a picture of urinary tract infection (leukocyturia and bacteriuria). The microscopic analysis of urinary sediment revealed the presence of urothelial cells and leukocytes internalized in urothelial cells. Anti-CD68 (membrane marker of macrophages) was tested by immunocytochemistry and a negative result was observed. Based on the findings phagocytosis of apoptotic cells mediated by urothelial cells was identified. This phenomenon can be observed in urinary sediment and should not be confused with a neoplastic process since it is a physiological event of cell elimination.  相似文献   
104.
BackgroundTo finish an endurance race, athletes perform a vigorous effort that induces the release of cardiac damage markers. There are several factors that can affect the total number of these markers, so the aim of this review was to analyze the effect of endurance running races on cardiac damage markers and to identify the factors that modify the levels of segregation of these cardiac damage markers.MethodsA systematic search of PubMed, Web of Science, and the Cochrane Library databases was performed. This analysis included studies where the acute effects of running races on cardiac damage markers (troponin I and troponin T) were analyzed, assessing the levels of these markers before and after the races.ResultsThe effects of running races on troponin I (mean difference = 0.0381 ng/mL) and troponin T (mean difference = 0.0256 ng/mL) levels were significant. The ages (R2 = 14.4%, p = 0.033) and body mass indexes (R2 = 14.5%, p = 0.045) of the athletes had a significant interaction with troponin I. In addition, gender, mean speed, time to finish the race, and type of race can affect the level of cardiac damage markers.ConclusionEndurance running races induce the release of cardiac-damage markers that remain elevated for at least 24 h after the races. In addition, young male athletes with high body mass indexes who perform races combining long duration and moderate intensity (i.e., marathons) release the highest levels of cardiac damage markers. Physicians should take into consideration these results in the diagnosis and treatment of patients admitted to the hospital days after finishing endurance running races.  相似文献   
105.
选择 9只 6 - 10月龄的健康雄性白山羊 ,经粪便检查和DotBLISA检测 ,确认无肝片吸虫感染 ,随机分成感染组 (n =5 )和对照组 (n =4 ) ,试验组每只一次口服接种 15 0个肝片吸虫囊蚴。每周定时从颈静脉采集感染前 0周和感染后 14周血液一次 ,分离血清 ,测定血清中的钾、钙、钠、镁、磷、氯等无机盐的含量 ,旨在研究感染肝片吸虫对山羊机体无机盐含量的影响。结果表明感染后山羊血清中的钾、钠、钙、镁、磷、氯的含量均成波动变化 ,说明肝片吸虫感染后机体无机盐含量发生了不同程度的变化 ,这与虫体感染后机体的代谢发生改变有关。  相似文献   
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107.
For a group of goldfish trained in a runway under conditions of highly massed practice, reduction in magnitude of reward produced a gradual decline in performance to the level of a small-reward control group but no suggestion of negative successive contrast. These results are consistent with the suggestion that reward plays a somewhat different role in the learning of fish and rats. They also serve to extend the range of conditions under which the stimulus aftereffects of reward come to control the instrumental behavior of fish.  相似文献   
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109.
Research Findings: The purpose of this study was to examine within-group individual differences in the code-related and oral language abilities of an economically stressed Spanish-speaking English language learner (ELL) preschool sample and to evaluate the predictive relationship of these differences to later listening comprehension. Latent class analysis was used to identify similarities in both the latent and outcome variables to form classes of students with similar profiles on the measured variables. Our 1st finding confirmed the existence of 4 distinct psychometrically validated profiles: (a) Low English Language, Average Spanish Language, Mixed Spanish Code-Related (prevalence 19.4%); (b) Average English Language, Strengths in Spanish Language and Spanish Code-Related (24.2%); (c) Mixed English and Spanish Language, Low Spanish Code-Related (prevalence 34%); and (d) High English Language, Average Spanish Language, Mixed Spanish Code-Related (prevalence 22%). The resulting profiles demonstrated that English and Spanish code- and language-related domains of emergent literacy developed unevenly across the Spanish-speaking ELL preschoolers. Relative strengths and weaknesses in code- and language-related skills were also found to be meaningfully related to end-of-year listening comprehension—a precursor to reading comprehension. Finally, profiles yielded meaningful variability along sociodemographic variables. Practice or Policy: Implications, limitations, and directions for future research are discussed.  相似文献   
110.
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