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81.
R. I. Mustafin A. A. Protasova G. Van den Mooter V. A. Kemenova 《Pharmaceutical Chemistry Journal》2005,39(12):663-666
With a view to the development of new controlled drug delivery systems, the formation of an interpolyelectrolyte complex (IPEC)
between chitosan (CTS) and Eudragit L100 (L-100) has been studied. The structure of this IPEC is such that two maxima are
observed in the curves of IPEC swelling in the media with different pH values. The release of a model drug (ibuprofen) from
IPEC-based tablets is significantly retarded, and this delay can be controlled by changing the molecular weight of CTS in
the IPEC composition.
__________
Translated from Khimiko-Farmatsevticheskii Zhurnal, Vol. 39, No. 12, pp. 44–46, December, 2005. 相似文献
82.
Scalp electrical recording during paralysis: quantitative evidence that EEG frequencies above 20 Hz are contaminated by EMG. 总被引:2,自引:0,他引:2
Emma M Whitham Kenneth J Pope Sean P Fitzgibbon Trent Lewis C Richard Clark Stephen Loveless Marita Broberg Angus Wallace Dylan DeLosAngeles Peter Lillie Andrew Hardy Rik Fronsko Alyson Pulbrook John O Willoughby 《Clinical neurophysiology》2007,118(8):1877-1888
OBJECTIVE: To identify the possible contribution of electromyogram (EMG) to scalp electroencephalogram (EEG) rhythms at rest and induced or evoked by cognitive tasks. METHODS: Scalp EEG recordings were made on two subjects in presence and absence of complete neuromuscular blockade, sparing the dominant arm. The subjects undertook cognitive tasks in both states to allow direct comparison of electrical recordings. RESULTS: EEG rhythms in the paralysed state differed significantly compared with the unparalysed state, with 10- to 200-fold differences in the power of frequencies above 20 Hz during paralysis. CONCLUSIONS: Most of the scalp EEG recording above 20 Hz is of EMG origin. Previous studies measuring gamma EEG need to be re-evaluated. SIGNIFICANCE: This has a significant impact on measurements of gamma rhythms from the scalp EEG in unparalysed humans. It is to be hoped that signal separation methods will be able to rectify this situation. 相似文献
83.
Peter Turrone Gary Remington Shitij Kapur José N Nobrega 《Neuropsychopharmacology》2003,28(8):1433-1439
Accumulating evidence suggests that antipsychotics (APs) that lead to sustained blockade of dopamine D(2) receptors are more likely to induce acute extrapyramidal side effects (EPS) compared to APs that only occupy D(2) receptors transiently. It is unclear, however, whether a similar relationship exists for long-term AP-induced motoric side effects like tardive dyskinesia (TD). The objective of this study was to ascertain whether transient (via daily subcutaneous (s.c.) injections) vs continuous (via osmotic minipump) AP-induced D(2) receptor occupancy differentially affects the development of haloperidol-induced vacuous chewing movements (VCMs), an animal model of TD. Six groups of 12 rats received 0.1, 0.25, or 1 mg/kg of haloperidol or vehicle (n=36) via osmotic minipump (to provide within-day sustained) or daily s.c. injection (within-day transient) for 8 weeks. VCMs were measured on a weekly basis and D(2) occupancy levels were measured in vivo using [(3)H]-raclopride at the end of the experiment. Minipump-treated rats developed HAL dose-dependent D(2) occupancies of 0.1 mg/kg/day (57%), 0.25 mg/kg/day (70%), and 1 mg/kg/day (88%). S.C.-treated rats also developed HAL dose-dependent D(2) occupancies of 0.1 mg/kg/day (83% peak, 3% trough), 0.25 mg/kg/day (89% peak, 0% trough), and 1 mg/kg/day (94% peak, 17% trough). A total of 43% of rats given 0.25 and 1 mg/kg/day of HAL via minipump developed high VCMs compared to only 8% of the rats given the same doses via daily s.c. injections. The 0.1 mg/kg dose did not give rise to VCMs beyond vehicle levels regardless of the route of administration. These findings support the contention that D(2) occupancy levels induced by chronic HAL must be high and sustained through the day before significant risk of VCMs, and perhaps also TD, emerges. 相似文献
84.
85.
86.
Healthcare information systems (HISs) are often implemented to enhance the quality of care and the degree to which it is patient-centered,
as well as to improve the efficiency and safety of services. However, the outcomes of HIS implementations have not met expectations.
We set out to organize the knowledge gained in qualitative studies performed in association with HIS implementations and to
use this knowledge to outline an updated structure for implementation planning. A multi-disciplinary team performed the analyses
in order to cover as many aspects of the primary studies as possible. We found that merely implementing an HIS will not automatically
increase organizational efficiency. Strategic, tactical, and operational actions have to be taken into consideration, including
management involvement, integration in healthcare workflow, establishing compatibility between software and hardware and,
most importantly, user involvement, education and training. The results should be interpreted as a high-order scheme, and
not a predictive theory. 相似文献
87.
88.
Factors affecting aseptic loosening of 4750 total hip arthroplasties: multivariate survival analysis
Barbara Bordini Susanna Stea Manuela De Clerico Sergio Strazzari Antonio Sasdelli Aldo Toni 《BMC musculoskeletal disorders》2007,8(1):69
Background
Total hip arthroplasty is a successful surgery, that fails at a rate of approximately 10% at ten years from surgery. Causes for failure are mainly aseptic loosening of one or both components partially due to wear of articular surfaces and partially to design. The present analysis aimed to identify risk factors and quantify their effects on aseptic failure. 相似文献89.
90.
Michael T Fitch David E Manthey Henderson D McGinnis Bret A Nicks Manoj Pariyadath 《BMC medical education》2008,8(1):38