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Manraj K. Phull Trevor Eydmann Judy Roxburgh Justin R. Sharpe Diana J. Lawrence-Watt Gary Phillips Yella Martin 《Journal of materials science. Materials in medicine》2013,24(2):461-467
The restoration of body contours as shaped by adipose tissue remains a clinical challenge specifically in patients who have experienced loss of contour due to trauma, surgical removal of tumours or congenital abnormalities. We have developed a novel macro-microporous biomaterial for use in soft tissue re-bulking and augmentation. Alginate beads provided the pore template for the construct. Incorporation, and subsequent dissolution, of the beads within a 7 % (w/v) gelatin matrix, produced a highly porous scaffold with an average pore size of 2.01 ± 0.08 mm. The ability of this scaffold to support the in vitro growth and differentiation of human adipose-derived stem cells (ADSCs) was then investigated. Histological analysis confirmed that the scaffold itself provided a suitable environment to support the growth of ADSCs on the scaffold walls. When delivered into the macropores in a fibrin hydrogel, ADSCs proliferated and filled the pores. In addition, ADSCs could readily be differentiated along the adipogenic lineage. These results therefore describe a novel scaffold that can support the proliferation and delivery of ADSCs. The scaffold is the first stage in developing a clinical alternative to current treatment methods for soft tissue reconstruction. 相似文献
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This study is concerned with whether the correlation between complex working memory spans and reading comprehension occurs because the complex spans reflect the capacity of a structural working memory that plays a causal role in comprehension or because a 3rd factor, word knowledge, plays a causal role in both the span tasks and comprehension. If the latter hypothesis is correct, the correlation between word span and reading comprehension should be large when span is tested with low-frequency words but should not occur when span is tested with very familiar words. 90 college students were tested on a simple and a complex version of the word span task with high- and low-frequency words. The Verbal Scholastic Aptitude Test (VSAT) was used as a measure of reading comprehension. The correlation between span and VSAT was somewhat higher when span was tested with low-frequency words, but was significant with both low- and high-frequency words. This suggests that both word knowledge and a content-free working memory play a causal role in the relationship between word span and higher level cognitive tasks. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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TV Ellerbrock PE Harrington TJ Bush SA Schoenfisch MJ Oxtoby JJ Witte 《Canadian Metallurgical Quarterly》1995,86(3):400-404
OBJECTIVE: To investigate why women who use crack cocaine are at increased risk of human immunodeficiency virus (HIV) infection. METHODS: One thousand one hundred fifty-two (99.7%) of 1155 consecutive prenatal patients attending a rural public health clinic were interviewed about drug use and sexual practices and tested for HIV infection and other sexually transmitted diseases. RESULTS: Fifty-one (4.7%) of 1096 pregnant women reported ever using crack cocaine, but only five (10%) of the crack cocaine users had ever injected drugs. Eighteen (35%) of the crack users were HIV infected compared with 22 (2%) of the 1045 women who reported never using crack (odds ratio 25, 95% confidence interval 12-52; P < .001). Crack users were more likely to have had a known HIV-infected sex partner, exchanged sex for money or drugs, and tested positive for syphilis than were non-crack users (for each comparison, P < .001). Before using crack, 18% of crack users had exchanged sex for money or drugs and 8% had averaged three or more sex partners per month; in contrast, after beginning to use crack, 76% of crack users exchanged sex for money or drugs and 63% averaged three or more sex partners per month (for both comparisons, P < .001). Crack users who were not HIV infected were more likely to have almost always used condoms and/or had fewer than three sex partners per month than were HIV-infected crack users (P < .01). CONCLUSION: Women who reported using crack cocaine were at an increased risk of HIV infection because crack use was associated with a significant increase in unprotected sexual contact. 相似文献
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Forgiveness is one construct that is beginning to demonstrate promise as a health and relationship promoter within the workplace. The primary aim of this research was to examine the effects of one psychological intervention (social motivational training) that was developed to promote forgiveness among co-workers. In the first of two studies, workers were randomly assigned to one of two intervention conditions (i.e., job satisfaction training, social motivational training). Participants read a vignette in which they were to imagine themselves as victims of a co-worker transgression. Judgments of responsibility and co-worker forgiveness were then measured at two intervals: before and after training. In Study 2, workers recounted an actual critical incident involving a co-worker transgression, completed a pretraining questionnaire measuring judgments of responsibility, self-image, and forgiveness, received either a one-on-one job satisfaction training or social motivational training session, and completed a post-training questionnaire. Results from both studies indicated that social motivational training enhanced participants' forgiveness of a hypothetical and actual co-worker. In addition, Study 2 showed an increase in workers' self-image following social motivational training, suggesting affirmation of the self as a possible mechanism for the effects of social motivational training on forgiveness. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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