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991.
Caryn E. Peterson Rebecca L. Sedjo Faith G. Davis Craig A. Beam Anna R. Giuliano 《Nutrition and cancer》2013,65(6):728-733
Persistent infection with human papillomavirus (HPV) is the primary etiologic factor for cervical cancer. The synergistic effect of carotenoids on HPV persistence has not been examined. To explore these potential synergies, we developed 2 measures of carotenoid status using circulating and dietary intake nutrients in which each nutrient was given equal weighting. We then compared persistent HPV infection with its counterpart, intermittent infection. In the analysis using the Crude Index, no association was observed between circulating nutrients and persistent infection with oncogenic HPV [odds ratio (OR)adjusted = 0.8, 95% confidence interval (CI) = 0.3–2.2)] or any type HPV (ORadjusted = 0.8, 95% CI = 0.3–2.1). Similar results were obtained using the Cumulative Index. However, associations between dietary intake and persistent infection were observed using both indexes. When the analysis was restricted to oncogenic HPV, a 50% higher risk was observed for women with low dietary carotenoid status using the Crude Index (ORadjusted = 1.5, 95% CI = 0.6–3.7). In the analysis using any type HPV, the adjusted OR for women with low dietary intake of combined carotenoids using the Cumulative Index was 2.4 (95% CI = 1.1–5.2). These results may be consistent with the hypothesis that low levels of carotenoids may increase the risk of persistent HPV infection. 相似文献
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An fMRI investigation of the impact of withdrawal on regional brain activity during nicotine anticipation 总被引:1,自引:0,他引:1
Rebecca Gloria Lisa Angelos Hillary S. Schaefer James M. Davis Matthew Majeskie Burke S. Richmond John J. Curtin Richard J. Davidson Timothy B. Baker 《Psychophysiology》2009,46(4):681-693
Previous research indicates that drug motivational systems are instantiated in structures that process information related to incentive, motivational drive, memorial, motor/habit, craving, and cognitive control processing. The present research tests the hypothesis that activity in such systems will be powerfully affected by the combination of drug anticipation and drug withdrawal. Event-related fMRI was used to examine activation in response to a preinfusion warning cue in two experimental sessions that manipulated withdrawal status. Significant cue-induced effects were seen in the caudate, ventral anterior nucleus of the thalamus, the insula, subcallosal gyrus, nucleus accumbens, and anterior cingulate. These results suggest that withdrawal and nicotine anticipation produce (1) different motor preparatory and inhibitory response processing and (2) different craving related processing. 相似文献
994.
Ho Lee Gwendolyn Sowa Nam Vo Gianluca Vadala Stephen O'Connell Rebecca Studer James Kang 《The spine journal》2010,10(2):159-166
Background contextBupivacaine is a local anesthetic commonly used to relieve or control pain in interventional spine procedures. Bupivacaine has been shown to be toxic to articular cartilage, which has similarities to intervertebral disc (IVD) cartilage, raising concern over a potentially negative effect of bupivacaine on the disc.PurposeTo determine bupivacaine's effect on cell viability of IVD cells in vitro and to elucidate whether this is through apoptosis or necrosis.Study designIn vitro controlled study of bupivacaine effect on cell viability in human and rabbit IVD cells.SubjectsRabbit annulus fibrosus (AF) tissue, nucleus pulposus (NP) cells, and knee articular chondrocytes were isolated from New Zealand white rabbits. Human AF and NP cells were isolated from stage 3 to 4 degenerative disc surgical specimens.Outcome measuresCell viability was assessed after exposure to bupivacaine via trypan blue staining or flow cytometry.MethodsAnnulus fibrosus and NP cells were grown in monolayer and alginate beads, respectively, to simulate their physiologic environment. The cells were then exposed to bupivacaine or saline control at 60 and 120 minutes and examined for cell viability.ResultsRabbit NP cell death demonstrated a time and dose dependence in response to bupivacaine. In addition, cell death was greater than that observed for articular chondrocytes. Rabbit AF tissue also demonstrated increased cell death in response to bupivacaine exposure. Human NP cells demonstrated time-dependent cell death, with greater necrosis than apoptosis. Annulus fibrosus cells grown in monolayers also resulted in similar effects, with greater necrosis rather than apoptosis.ConclusionsDespite its pain relieving properties, bupivacaine decreases cell viability in rabbit and human disc cells in a time-dependent manner. In addition, the changes observed are greater than that seen for articular chondrocytes. This increase in cell death appears to be related to an increase in necrosis rather than apoptosis. Whether bupivacaine exerts similar effects in vivo or how this relates to overall clinical outcome remains to be explored. 相似文献
995.
Silvia B. Lomáscolo Douglas J. Levey Rebecca T. Kimball Benjamin M. Bolker Hans T. Alborn 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(33):14668-14672
Seed dispersal by vertebrates is one of the most common and important plant–animal mutualisms, involving an enormous diversity of fruiting plants and frugivorous animals. Even though plant reproduction depends largely on seed dispersal, evolutionary ecologists have been unable to link co-occurring traits in fruits with differences in behavior, physiology, and morphology of fruit-eating vertebrates. Hence, the origin and maintenance of fruit diversity remains largely unexplained. Using a multivariate phylogenetic comparative test with unbiased estimates of odor and color in figs, we demonstrate that fruit traits evolve in concert and as predicted by differences in the behavior, physiology (perceptive ability) and morphology of their frugivorous seed dispersers. The correlated evolution of traits results in the convergence of general appearance of fruits in species that share disperser types. Observations at fruiting trees independently confirmed that differences in fig traits predict differences in dispersers. Taken together, these results demonstrate that differences among frugivores have shaped the evolution of fruit traits. More broadly, our results underscore the importance of mutualisms in both generating and maintaining biodiversity. 相似文献
996.
Skepticism toward infant pain characterized much of 20th century research and clinical practice, with infant surgery routinely conducted with minimal or no anesthesia into the 1980s. This paper offers a historical exploration of how this view became common by reviewing and analyzing the experimental infant pain research of the 19th and early 20th centuries that contributed to the development of infant pain denial. These experiments used pinprick and electric shock, and the results were generally interpreted as evidence of infants’ underdeveloped pain perception, attributed to their lack of brain maturation. Even clear responses to noxious stimuli were often dismissed as reflex responding. Later these experimental findings were used by anesthesiologists to support the lessened use of anesthesia for infants. Based on the reviewed literature, this paper suggests that 4 interrelated causes contributed to the denial of infant pain: the Darwinian view of the child as a lower being, extreme experimental caution, the mechanistic behaviorist perspective, and an increasing emphasis on brain and nervous system development. Ultimately this history can be read as a caution to modern researchers to be aware of their own biases, the risks of null hypothesis testing, and a purely mechanistic view of infants.PerspectiveThis article reviews the history of 19th and early 20th century infant pain research, tracing how the widely accepted belief that infants could not feel pain developed in the period prior to the growing acceptance of infant pain. Four interrelated causes are posited to help explain the tolerance of infant pain denial until recent times. 相似文献
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Femoroacetabular impingement (FAI) can be associated with labral ossification, acetabular rim fractures, and os acetabuli. Typically, these fragments can be completely excised as part of a femoroacetabular impingement correction procedure. In rare instances, however, larger, weight-bearing fragments contribute to pincer-type impingement, but complete removal might create structural instability or dysplasia. We report the results of 2 such cases where partial resection of a rim fracture and internal fixation of the remaining fragment were performed to correct the impingement while preserving adequate acetabular coverage. Predictable pain relief, healing of the stabilized rim fragment, and improved outcome scoring were achieved in both cases at 2-year follow-up evaluation. 相似文献