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A method for time-resolved imaging that provides a flexible trade-off between imaging time and temporal resolution is presented. It is based on a view order selection technique that automatically segments the acquired raw data into appropriate temporal frames. When used with cardiac monitoring and phase-contrast imaging, data similar to that obtained with a conventional gated phase-contrast sequence are acquired rapidly. For many applications, the temporal resolution can be reduced enough to permit imaging within a breath-hold interval, while still allowing accurate time-averaged flow quantitation. This is a general technique that can be implemented within a variety of pulse sequences and can resolve other motion cycles, including the respiratory cycle. 相似文献
35.
Cheryl Tilse Jill Wilson Deborah Setterlund Linda Rosenman 《Australasian journal on ageing》2005,24(Z1):S51-S56
The management of the financial assets of older people is increasingly important in the current policy context. Competing interests from the state, the market and the family regarding the appropriate use of these assets suggest that non‐professional managers are assisting older people in a complex environment. This paper, based on a national prevalence study and an in‐depth study, explores the nature and extent of asset management on behalf of older people. It examines the role of legal provision for substitute decision‐making in these processes and concludes that the current provision is insufficient to protect older people from financial abuse and support carers to manage assets well. This paper proposes that more broadly based interventions are required in a complex environment of competing interests. Such interventions include attitudinal change, improved financial literacy, information and support for older people and informal asset managers and improved monitoring and support for substitute decision makers. 相似文献
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Mary Ann Marrazzi Jill M. Wroblewski Joseph Kinzie Elliot D. Luby 《The American journal on addictions / American Academy of Psychiatrists in Alcoholism and Addictions》1997,6(1):21-29
Studies have found naltrexone useful in the treatment of diseases other than opiate addiction in which endogenous opioids presumably play a role, such as alcoholism and eating disorders. Some of these studies involve high doses (100–200 mg bid). Because investigational studies with high doses (300 mg/day) reported clinically significant increases in liver enzyme levels, the authors measured a spectrum of liver function parameters in response to high doses of naltrexone in a double-blind, crossover trial (100 mg bid) followed by an open-label period (200 mg bid). They observed no adverse clinical or laboratory changes in liver function in association with high-dose naltrexone therapy in eating disorders. 相似文献
38.
Aspiration assessment and prevention in critically ill enterally fed patients: evidence-based recommendations for practice. 总被引:4,自引:0,他引:4
Jill S Sanko 《Gastroenterology nursing》2004,27(6):279-285
Providing nutrition to patients is a vitally important aspect of care. Enterally feeding even critically ill patients remains the method of choice for most prescribers; however, the decision to provide nutrition via the enteral route comes with the added concern of bronchopulmonary aspiration as a complication. The majority of the literature and research on enteral feeding is out of date and focuses primarily on ways to identify aspiration, rather then preventing it. Although much of this research and literature is not current, many valid and useful recommendations have been made that can be applied to current practice. These recommendations are synthesized in this article in an effort to improve the quality and safety of administration of enteral nutrition to critically ill patients. However, this compiled information is limited to the current resources. More research should be done to decrease the risk of aspiration in this delicate population. 相似文献
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Judith S. Weis Richard Cohen Jill K. Kwiatkowsi 《Aquatic toxicology (Amsterdam, Netherlands)》1987,10(5-6):279-290
Fiddler crabs, Uca pugilator, were exposed to the insect growth regulator diflubenzuron (Dimilin®) at 0.5, 5, and 50 μg/l after multiple autotomy of one chela and five walking legs. Regeneration of the first walking leg was monitored, and time to ecdysis, mortality, and morphology of the regenerated limbs observed. Continuous exposure to the chemical produced a dose-dependent retardation of regeneration. Animals molting in the higher concentrations exhibited significant mortality at ecdysis. Exposure to the pesticide for a single week produced similar but less severe effects. However, if crabs molted while in the pesticide, significant mortality was observed. The presence of sediment in the container with the crab moderated the effects of the pesticide, but did not eliminate them.
The regenerated limbs of the crabs that survived ecdysis were found to have lesions in the form of black areas in which the cuticle was improperly developed. These lesions were seen in crabs that had been in the pesticide for only one week (week 2 or week 3) as well as those that had had continuous exposure. They were also seen in crabs that regenerated in Dimilin with sediment. In addition, the number of setae on limbs was reduced compared to the number on limbs that had regenerated in clean sea water. 相似文献
40.
Despite evidence of an interaction between cannabinoids and estrogen in the brain, little information is available regarding the consequences of this interaction on behavior. A within-subjects design was used to examine the effects of estrogen and delta9-tetrahydrocannabinol (delta9-THC) on learning and memory in ovariectomized rats responding under a multiple schedule of repeated acquisition and performance. Treatment with low physiological levels of estrogen, delivered in Silastic capsules, improved response accuracy without affecting response rate during acquisition. Estrogen also attenuated the ability of delta9-THC (0.56- 3.2 mg/kg) to decrease response accuracy and rate during acquisition and response accuracy during performance. Results indicate that estrogen can improve accuracy during acquisition of a nonspatial operant task and can attenuate delta9-THC- induced behavioral deficits. 相似文献