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181.
Clinical features of chronic hepatitis B patients with YMDD mutation after lamivudine therapy 总被引:5,自引:0,他引:5
INTRODUCTION Chronic hepatitis B(CHB)remains a major public health problem,affecting more than350mil-lion people worldwide.Cirrhosis,liver failure,or hepatocellular carcinoma will develop in approxi-mately15to40percent of infected patients(Ganem and Prince,2004).Lamivudine,an oral nucleoside analogue,inhibits HBV replication(de Clercq,2001;2004;Lai et al.,1997;1998;Marcellin et al.,2004).It can markedly reduce serum HBV DNA levels and normalize alanine aminotransferase(ALT)levels … 相似文献
182.
183.
Rosalind Latiner Raby Janice Nahra Friedel Edward J. Valeau 《Community College Journal of Research & Practice》2016,40(11):961-964
This article is a comparative study of community colleges and global counterparts at 41 institutions in 25 countries. Policies from each country link completion of a college program to career entry and to advancement opportunities. National and institutional policies are being defined, benchmark data is being collected on goals in the process, and specific programs are being offered to increase the likelihood that students finish their educational programs. This article examined the emerging trajectories as defined by those who work in these institutions; and in so doing, it provided a discussion of completion in an international context. 相似文献
184.
Infant Affective Reactions to the Resumption of Maternal Interaction after the Still-Face 总被引:4,自引:0,他引:4
To investigate infants' reactions to the Face-to-Face Still-Face Paradigm and in particular the reunion episode, 50 6-month-olds' affective, behavioral, and physiologic reactions were recorded and analyzed. Infants reacted to the still-face with negative affect, a drop in vagal tone, and an increase in heart rate. By contrast, they reacted to the reunion episode with a mixed pattern of positive and negative affect. There was a carryover of negative affect from the still-face, an increase in fussiness and crying, and a rebound of positive affect. During this episode, the infants' heart rate and vagal tone returned to initial levels. The data indicate that infant affective displays are specifically related to different interactive events, but that their physiologic reactions do not show the same level of specificity. The findings also highlight the complexity of the affective and reparatory processes that take place in mother-infant interactions. 相似文献
185.
We trained 7 pigeons to discriminate visual displays of 16same items from displays of 16different items. The specific stimulus features of the items and the relations among the items could serve as discriminative stimuli.
Unlike in most studies of same-different discrimination behavior, we gave a small number of probe tests during each session
of acquisition to measure the time-course of control by the learning of specific stimulus features and relational cues. Both
the specific stimulus features and relational cues exerted reliable stimulus control, with the specific stimulus features
exerting more control during the final three fourths of same-different learning. These findings replicate research suggesting
that pigeons encode both the specific stimulus features and relational cues, and for the first time document the time-course
of control by each kind of cue. 相似文献
186.
Neuropsychology of Early-treated Phenylketonuria: Specific Executive Function Deficits 总被引:14,自引:0,他引:14
Marilyn C. Welsh Bruce F. Pennington Sally Ozonoff Bobbye Rouse Edward R. B. McCabe 《Child development》1990,61(6):1697-1713
This study explored the hypothesis that children with early-treated phenylketonuria (PKU) are selectively impaired on executive function measures, even when still on diet. The rationale for this hypothesis is that even mild elevations in phenylalanine (Phe) can lead to lower central levels of biogenic amines, including dopamine (DA). We hypothesize that this mild DA depletion causes subtle prefrontal dysfunction, which in turn affects executive functions such as set maintenance, planning, and organized search. 11 preschool early-treated PKU children (M age = 4.64) and a sample of age- and IQ-matched unaffected peers (n = 11) were evaluated on a battery of executive function (EF) measures. In addition, a "non-executive function" task, recognition memory, was administered to all subjects. Group comparisons demonstrated that PKU children were significantly impaired on an executive function composite score; there were no group differences, however, in recognition memory. These results supported the hypothesized specific deficit in executive function. Furthermore, within the PKU group the executive function composite score was significantly negatively correlated with concurrent phenylalanine levels, even after controlling for the correlation between IQ and executive function skills. This second finding provides support for the proposed biochemical mechanism underlying the specific cognitive deficits. 相似文献
187.
David Evenhouse Nimit Patel Maria Gerschutz Nick A. Stites Jeffrey F. Rhoads Edward Berger 《European Journal of Engineering Education》2018,43(5):664-678
Engineering education has been slow to adopt research-based educational innovations. Few prior works on such adoption have investigated the combined classroom experiences of instructors and students when such innovations are being implemented. Therefore, this work focuses on the lived experiences of an instructor and her students when adopting an active, blended, and collaborative learning environment, known as Freeform, in a second-year dynamics course. Weekly reflections from the instructor were processed alongside student interviews using Thematic Analysis to discern prominent themes in their perspectives for comparison and discussion. The results indicate that the instructor navigated internal tensions between her previous instructional preferences and the philosophy and resources of Freeform. Similarly, students had to adapt to this new philosophy and suite of resources that were uncommon for their institution. Ultimately, this work highlights the contextual natures of teaching and learning, and how situational factors can influence educational innovation. 相似文献
188.
van Lier PA Vitaro F Barker ED Brendgen M Tremblay RE Boivin M 《Child development》2012,83(5):1775-1788
This study explored whether early elementary school aged children’s externalizing problems impede academic functioning and foster negative social experiences such as peer victimization, thereby making these children vulnerable for developing internalizing problems and possibly increasing their externalizing problems. It also explored whether early internalizing problems contributed to an increase in externalizing problems. The study examined 1,558 Canadian children from ages 6 to 8 years. Externalizing and internalizing problems, peer victimization, and school achievement were assessed annually. Externalizing problems lead to academic underachievement and experiences of peer victimization. Academic underachievement and peer victimization, in turn, predicted increases in internalizing problems and in externalizing problems. These pathways applied equally to boys and girls. No links from internalizing to externalizing problems were found. 相似文献
189.
190.
Edward Martinez Jennifer Lindline Michael S. Petronis Maura Pilotti 《Journal of Science Education and Technology》2012,21(6):713-721
The Bureau of Labor Statistics projects an increase in Natural Resource Management (NRM) jobs within the next 10?years due to baby-boomer retirements and a 12% increase in demand for these occupations. Despite this trend, college enrollment in NRM disciplines has declined. Even more critical is the fact that the soon-to-be-majority Hispanic population is underrepresented in NRM disciplines. The goal of the present study was to determine if an in-residence, two-week, summer science program for underrepresented minorities would not only increase interest in science, actual science knowledge, and perceived science knowledge, but also have an overall impact on underrepresented minority students?? decisions to attend college, major in a scientific discipline and pursue a career in science. During a four-year period, 76 high school students participated in a Science Agricultural Summer Experience (SASE) in Northern New Mexico. A pre/post science-knowledge exam and satisfaction survey were administered to participants. We demonstrate that participants improved significantly (p?<?.05) in all areas measured. In particular, comfort with science field and lab activities, science knowledge and perceived science knowledge were enhanced after exposure to the program. Students not only found science exciting and approachable after participation, but also exhibited increased interest in pursuing a degree and career in science. Of the 76 SASE participants within graduation age (n?=?44), all graduated from high school; and 86% enrolled in college. These findings suggest that the implemented SASE initiative was effective in recruiting and increasing the confidence and abilities of underrepresented minority students in science. 相似文献