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991.
Purpose
Recent data indicate that night shift work is associated with increased endometrial cancer risk, perhaps through a pathway involving lower melatonin production. Melatonin is an antiestrogenic hormone, with production in a circadian pattern that is dependent on presence of dark at night. Sleep duration is positively associated with melatonin production and may be an indicator of melatonin levels in epidemiologic studies. 相似文献992.
993.
Cisplatin is a widely used and highly effective cancer chemotherapeutic agent. One of the limiting side effects of cisplatin use is nephrotoxicity. Research over the past 10 years has uncovered many of the cellular mechanisms which underlie cisplatin-induced renal cell death. It has also become apparent that inflammation provoked by injury to renal epithelial cells serves to amplify kidney injury and dysfunction in vivo. This review summarizes recent advances in our understanding of cisplatin nephrotoxicity and discusses how these advances might lead to more effective prevention. 相似文献
994.
Matrix metalloproteinase-3 expression profile differentiates adaptive and maladaptive synaptic plasticity induced by traumatic brain injury 总被引:1,自引:0,他引:1
The interaction between extracellular matrix (ECM) and regulatory matrix metalloproteinases (MMPs) is important in establishing and maintaining synaptic connectivity. By using fluid percussion traumatic brain injury (TBI) and combined TBI and bilateral entorhinal cortical lesion (TBI + BEC), we previously demonstrated that hippocampal stromelysin-1 (MMP-3) expression and activity increased during synaptic plasticity. We now report a temporal analysis of MMP-3 protein and mRNA response to TBI during both degenerative (2 day) and regenerative (7, 15 day) phases of reactive synaptogenesis. MMP-3 expression during successful synaptic reorganization (following unilateral entorhinal cortical lesion; UEC) was compared with MMP-3 expression when normal synaptogenesis fails (after combined TBI + BEC insult). Increased expression of MMP-3 protein and message was observed in both models at 2 days postinjury, and immuohistochemical (IHC) colocalization suggested that reactive astrocytes contribute to that increase. By 7 days postinjury, model differences in MMP-3 were observed. UEC MMP-3 mRNA was equivalent to control, and MMP-3 protein was reduced within the deafferented region. In contrast, enzyme mRNA remained elevated in the maladaptive TBI + BEC model, accompanied by persistent cellular labeling of MMP-3 protein. At 15 days survival, MMP-3 mRNA was normalized in each model, but enzyme protein remained higher than paired controls. When TBI + BEC recovery was enhanced by the N-methyl-D-aspartate antagonist MK-801, 7-day MMP-3 mRNA was significantly reduced. Similarly, MMP inhibition with FN-439 reduced the persistent spatial learning deficits associated with TBI + BEC insult. These results suggest that MMP-3 might differentially affect the sequential phases of reactive synaptogenesis and exhibit an altered pattern when recovery is perturbed. 相似文献
995.
Biggs QM Fullerton CS Reeves JJ Grieger TA Reissman D Ursano RJ 《The American journal of orthopsychiatry》2010,80(4):586-592
Early posttraumatic psychiatric disorders have not been well studied in disaster workers. This study examined the rates of probable acute stress disorder (ASD), probable depression, increased tobacco use, and their associated risk factors in 9/11 World Trade Center disaster workers. Surveys were obtained from 90 disaster workers (e.g., medical personnel, police, firefighters, search and rescue) 2-3 weeks after 9/11. Nearly 15% of disaster workers had probable ASD and 26% had probable depression. Probable ASD and depression were highly related to functional impairment. The risk for ASD was increased for those with 9/11-specific disaster exposures, more pre-9/11 trauma exposures, and the peritraumatic dissociative symptom of altered sense of time. Disaster workers who were younger, non-White, or who had increasing numbers of peritraumatic dissociative symptoms were more likely to have probable depression. More than half of tobacco users increased their tobacco use after 9/11. Additionally, all tobacco users with probable ASD and almost all tobacco users with probable depression increased tobacco use. Rapid mobilization of resources for early screening and intervention and health promotion campaigns aimed at improving adverse health-related behaviors may be helpful for this high-risk group. 相似文献
996.
Stephen H. Butler Stephanie Rossit Iain D. Gilchrist Casimir J.H. Ludwig Bettina Olk Keith Muir Ian Reeves Monika Harvey 《Neuropsychologia》2009,47(12):2488-2495
We tested patients suffering from hemispatial neglect on the anti-saccade paradigm to assess voluntary control of saccades. In this task participants are required to saccade away from an abrupt onset target. As has been previously reported, in the pro-saccade condition neglect patients showed increased latencies towards targets presented on the left and their accuracy was reduced as a result of greater undershoot. To our surprise though, in the anti-saccade condition, we found strong bilateral effects: the neglect patients produced large numbers of erroneous pro-saccades to both left and right stimuli. This deficit in voluntary control was present even in patients whose lesions spared the frontal lobes. These results suggest that the voluntary control of action is supported by an integrated network of cortical regions, including more posterior areas. Damage to one or more components within this network may result in impaired voluntary control. 相似文献
997.
998.
A 42-year-old right-handed man with major depression, posttraumatic stress disorder, gastroesophageal reflux disease, and hypertension received 7 treatments of right unilateral electroconvulsive therapy, with the only complications being elevated blood pressure up to 180/120 mm Hg and agitation upon awakening. During eighth treatment, he experienced blood pressures as high as 210/130 mm Hg with severe agitation upon awakening from anesthesia followed by pulmonary edema. Pulmonary edema is rarely seen as a complication in electroconvulsive therapy, but if the airway becomes obstructed or there is excessive sympathetic discharge during the procedure, pulmonary edema may be more likely to occur. 相似文献
999.
1000.