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51.
Background/aim: Currently, the liver is cold-preserved at 0-4 ℃ for experimental and clinical purposes. Here, we investigated whether milder hypothermia during the initial phase of the preservation period was beneficial for liver viability upon reperfusion. Methods: In the first set of experiments, rat livers were preserved either conventionally in clinically used histidine-trypthopan-ketoglutarate (HTK) solution (Group A: 45 min and Group B: 24 h) or by slow cooling HTK solution (from 13 ℃ to 3 ℃) during the initial 45 min of preservation (Group C: 24 h). In the second set of experiments, additional groups of livers were evaluated: Group BB-preservation according to Group B and Group CC-preservation according to Group C. Further, some livers were preserved at 13 ℃ for 24 h. Livers were then reperfused using a blood-free perfusion model. Results: Bile production was approximately 2-fold greater in Group C compared to Group B. Alanine transaminase (ALT) and aspartate transaminase (AST) release into perfusate were 2-3-fold higher in Group B compared to Group C. No significant differences were found in ALT and AST release between Group C and Group A. Livers in Group CC compared to Group BB exhibited significantly lower portal resistance, greater oxygen consumption and bromosulfophthalein excretion into bile and lower lactate dehydrogenase (LDH) release into perfusate. Histological evaluation of tissue sections in Group BB showed parenchymal dystrophy of hepatocytes, while dystrophy ofhepatocytes was absent in Group CC. Livers preserved at 13 ℃ for 24 h exhibited severe ischemic injury Conclusion: These results suggest that the conventional way of liver preservation is not suitable at least for rat livers and that slow cooling of HTK solution during the initial phase of cold storage can improve liver viability during reperfusion.  相似文献   
52.
治部真里  李颖 《情报工程》2015,1(2):008-020
日本版NIH及其制药企业,政策制定·战略规划需要佐证。本研究尝试基于新的指标体系进行制药产业的现状俯瞰与预测未来。连载第三篇着眼于持有在研药物(pipeline)主体的规模及其种类,分析了掌控医药品开发的关键主体。其结果表明美国的强项在于中小企业与创业企业。另一方面,日本中小企业与创业企业没有承担像美国那样的角色。  相似文献   
53.
Two experimental studies examined the effects of different types of phonemic segmentation training on phonemic segmentation, reading and spelling. Children with learning disabilities, who were weak in phonemic segmentation, were trained with the use of diagrams and alphabet letters, with alphabet letters only, or with no visual support at all (the control condition). For this purpose three computer-assisted training programs were developed. In the first experiment, 48 children were assigned to one of the three programs. The training period lasted five weeks. Although in each training program the children improved their phonemic segmentation skill, there were no significant differences among the three training programs. This result may have been influenced by the different types of feedback that were provided in the three training programs. In a second experiment, therefore, these differences in feedback were eliminated and 49 different children were trained with the same three programs. The results of this experiment, however, were the same as those of the first experiment. The finding that visual support had no beneficial effects could therefore not be attributed to differences in explicit feedback. It was concluded that with these children, in contrast to preschoolers, phonemic segmentation training using visual support does not have any advantage over auditory training alone. The results of this study indicate that preschoolers and children with reading and spelling problems cannot be treated in the same way. It underlines the importance of further examination of the problems that poor readers and poor spellers encounter in grasping the structure of spoken language.  相似文献   
54.
Agreement between 57 African American mothers and their early adolescent daughters on measures of maternal support, maternal restrictive control, and parent-adolescent conflict were examined. To assess the relative validity of these reports, the study then evaluated them against the ratings of independent observers. Additionally, mother and daughter reports were combined to examine validity coefficients based on aggregate scores of each construct. All analyses were based on 2 sets of objective criterion ratings, ratings provided by coders of similar ethnic background (African American) and coders who were ethnically dissimilar (non-African American) to the families they rated. Overall, adolescents provided ratings that were more valid than those of their mothers when evaluated against both sets of independent ratings. Adolescent ratings of maternal control and parent-adolescent conflict converged at significantly higher levels than the ratings provided by their mothers. Maternal and adolescent reports of maternal support converged with objective criteria at statistically comparable levels. Validity coefficients for adolescent reports were also higher than those based on aggregate mother-daughter scores. Secondary analyses further revealed that African American coders rated mothers as less controlling and rated the dyadic interactions as less conflictual, and that their ratings were more consistent with the perceptions of the African American mothers and adolescents than were those provided by non-African American coders.  相似文献   
55.
A small group of children and young adolescent with dyslexia has severely impaired reading skills despite prolonged special education. These are the students in focus. In dyslexia, problem behaviour, internalised as well as externalised, has previously been reported, so also for the participants with dyslexia in this study. The aim of the present study was to obtain more in‐depth knowledge of the behaviour problems from various informants, representing different settings. This kind of information is imperative for identifying problem behaviour, and for planning and implementing remedial programmes. A clinical group of 70 students with severe dyslexia, due to phonological problems, and a control group of 70 without reading problems participated. The two groups were pair‐wise matched on age, gender, cognitive level and whether they lived in rural or urban areas. Mean age was 150 months, and mean IQ was approximately 100 in both groups. Parents, teachers and participants provided information on behaviour through the Achenbach questionnaires Child Behavior Checklist, Teacher's Report Form and Youth Self Report. Behaviour is, in these questionnaires, divided into eight syndrome areas called Withdrawn, Somatic Complaints, Anxious/Depressed, Social Problems, Thought Problems, Attention Problems, Delinquent Behavior and Aggressive Behavior. The three informant groups reported significantly more problems in the dyslexia group than in the controls in all the syndrome areas. Parents reported more children with dyslexia to be anxious and depressed, and have social problems and attention problems than teachers. They also reported suicidal ideations in nine participants with dyslexia. In addition, parents rated more internalising and total problems in the dyslexia group than teachers.  相似文献   
56.
In this article, we examine the construction of word meaning by students during collaborative activities in a multicultural classroom at a Dutch primary school. The analysis is based on recordings of student talk in small groups of four or five students during mathematics lessons. Difficulties with specific terms and expressions frequently arose during group work. Students could easily ask each other about the meaning of difficult words as a part of the collaborative activities they were accustomed to. In the groups with both Dutch and minority children, the minority students addressed their Dutch classmates as language experts. Conversations about language difficulties also occurred in the groups with only minority students. The conversations about word meaning revealed four patterns: (1) ignoring a question about the meaning of a word, (2) showing the meaning using gestures, (3) explaining, or (4) discussing word meaning. In none of the cases were the language problems solved by referring to the everyday meaning of the word. Instead, the conversations focussed directly on the specialised meaning which the word had in the context of the mathematics lesson. This means that the children used the mathematical discourse as a mediational tool for constructing a mathematical meaning of the words.  相似文献   
57.
When studying verbal materials, both adults and children are often poor at accurately monitoring their level of learning and regulating their subsequent restudy of materials, which leads to suboptimal test performance. The present experiment investigated how monitoring accuracy and regulation of study could be improved when learning idiomatic phrases. Elementary school children (fourth and sixth-graders) were instructed to predict their test performance by providing judgments of learning (JOLs). They provided JOLs immediately after studying each idiom, after studying all idioms, or after studying all idioms followed by generating sentences in which the idioms were used. Correlations between JOLs and test performance showed that delayed-JOLs and delayed-JOLs with sentence generation were more accurate than immediate JOLs. JOLs after sentence generation also improved regulation of study compared to delayed-JOLs only. Analyses of JOL reaction times suggest that delayed-JOLs led children to retrieve the literal meaning of the idiom, whereas JOLs after sentence generation led children to focus on connections between studied information, contextual information, and prior knowledge. Sentence generation presents a promising method to improve regulation of study, and thus idiom learning.  相似文献   
58.
This article discusses the pros and cons of transnational higher education offerings from the vantage point of a small Central European country, the Slovak Republic, and with special reference to franchising. Transnational higher education offerings are definitely needed, not only in the Slovak Republic, but in the other countries of Central and Eastern Europe as well, existing national higher education systems and institutions not being sufficiently developed to cope with increasing enrolment pressures. But there need to be adequate safeguards against fraudulent offerings, debased standards, and other such problems. The implantation of two franchised campuses of City University, Bellevue, Washington (USA) is cited as a very positive example of a foreign higher education institution that has been able to successfully integrate itself into the fabric of Slovak higher education by faithfully complying with all Slovak higher education regulations and offering high-quality course programmes.  相似文献   
59.
The main aim of this study was to examine second language production and discrimination skills in the light of musical aptitude. Our study was conducted in university settings in south-western Finland. English was used as a model for the second language due to its popularity among young adults. There were three types of tests used in this study: a pronunciation test, a phonemic listening discrimination task, and the Seashore test as an index of the musical aptitude. All the participants performed equally well in the phonemic listening discrimination task. However, the participants with higher musical aptitude were able to pronounce English better than the participants with less musical aptitude. The results, therefore, imply that musical and linguistic skills are interconnected.  相似文献   
60.
We evaluate the performance of the most common estimators of latent Markov (LM) models with covariates in the presence of direct effects of the covariates on the indicators of the LM model. In LM modeling it is common practice not to model such direct effects, ignoring the consequences that might have on the overall model fit and the parameters of interest. However, in the general literature about latent variable modeling it is well known that unmodeled direct effects can severely bias the parameter estimates of the model at hand. We evaluate how the presence of direct effects in?uences the bias and efficiency of the 3 most common estimators of LM models, the 1-step, 2-step, and 3-step approaches. Furthermore, we propose amendments (that were thus far not used in the context of LM modeling) to the 2- and 3-step approaches that make it possible to account for direct effects and eliminate bias as a consequence. This is done by modeling the (possible) direct effects in the first step of the stepwise estimation procedures. We evaluate the proposed estimators through an extensive simulation study, and illustrate them via a real data application. Our results show, first, that the augmented 2-step and 3-step approaches are unbiased and efficient estimators of LM models with direct effects. Second, ignoring the direct effects leads to biased estimates with all existing estimators, the 1-step approach being the most sensitive.  相似文献   
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