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991.
We have combined an anterior segment (AS) optical coherence tomography (OCT) system and a wavefront-based aberrometer with an approach that senses ocular wavefront aberrations using the OCT beam. Temporal interlacing of the OCT and aberrometer channels allows for OCT images and refractive error measurements to be acquired continuously and in real-time. The system measures refractive error with accuracy and precision comparable to that of clinical autorefractors. The proposed approach provides a compact modular design that is suitable for integrating OCT and wavefront-based autorefraction within the optical head of the ophthalmic surgical microscope for guiding cataract surgery or table-top devices for simultaneous autorefraction and ocular biometry.  相似文献   
992.
A bstract Background : The creation of free muscle grafts for surgical myoplasty is limited by the dependence of muscle on its original nerve supply. The aim of this study was to develop a model of gradual denervation of a large skeletal muscle (latissimus dorsi) and evaluate the possibility that atrophic degeneration and loss of function would be reduced using progressive nerve compression instead of surgical division of the nerve. The effects of chronic stimulation prior to, and after, denervation were also evaluated. Methods : Electrodes connected to a myostimulator were implanted on 24 latissimus dorsi muscles of 12 goats. Denervation of these muscles was achieved either by sectioning of the nerve or by progressive compression using ameroid rings placed around the nerve. Electrostimulation of the muscle started either 5 weeks before (prestimulation), or immediately after the denervation. Results : The model of gradual nerve compression was successfully created and did have less atrophy and loss of function at mid-term when compared with nerve division. Chronic electrostimulation of the muscle after nerve division had a beneficial effect on function and on the atrophic process. Chronic electrostimulation in our model of gradual nerve compression did not mirror these beneficial results. Detrimental results were observed in groups in which chronic electrostimulation was applied prior to nerve division or constriction.  相似文献   
993.
994.
The influences of food, tablet splitting, and fractional dosing on the pharmacokinetics of a new controlled-release double-scored tablet containing 60 mg isosorbide-5-mononitrate (Monoket Multitab) were investigated in healthy male volunteers. Food interaction was evaluated after single dose administration under fasted conditions and after a standard high-fat breakfast. The effect of tablet splitting was assessed at steady-state, after 5 days of once daily dosing with the tablet taken intact or trisected. The influence of fractional dosing was assessed after 1 and 6 days of daily regimen of 40 mg in the morning (2/3 of a tablet) and 20 mg in the evening (1/3 of a tablet). The pharmacokinetics of isosorbide-5-mononitrate after taking the tablet intact or in three fragments were very similar with a mere 10% increase of maximum plasma concentration (C(max)) for the latter, while the time to peak (T(max)) decreased from 5 to 4 h and areas under the concentration vs. time curves (AUCs) were virtually unchanged. Morning trough concentration reached 53 and 46 ng/ml, respectively. Administration of the intact tablet after a high-fat breakfast increased C(max) by 18% and AUC by 21%, and slightly delayed T(max) from 5 to 6h. During fractional dosing, morning and evening C(max) reached 364 and 315 ng/ml on the first day, and 373 and 300 ng/ml on the 6th day, respectively. The ratio of AUC(0-24 h) on the last day to AUC(infinity) on the first day, was 82.1% (confidence limits 71.7-94.1%) possibly resulting from peripheral volume expansion. The release characteristics of Monoket Multitab are thus moderately influenced by concomitant intake of food and to a very minor extent by tablet breaking. Fractional dosing allows to achieve lower peak and higher morning trough levels, while total exposure is comparable to that during once daily dosing (AUC(0-24 h, s.s.) of 5.55+/-1.78 and 5.71+/-1.08 microg h/ml).  相似文献   
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996.
997.
J001X, an acylated poly-(1,3)-galactoside isolated from Klebsiella pneumoniae proteoglycan, has been developed to target cells from the monocyte-macrophage lineage. Recent experimental work and initial clinical trials have proved the potential of this molecule labeled with 99mTc for the scintigraphy of inflammatory foci. In a model of radiation-induced inflammation in pigs, the scintigraphic contrast was observed to be very sensitive to a single injection of methylprednisolone given 12 h before scintigraphy. The present study was undertaken to confirm this effect and to estimate the possible interference of various anti-inflammatory agents on the in vivo targeting of macrophages by J001X. Methylprednisolone, dexamethasone, indomethacin and methotrexate used at an immunosuppressive dose were tested to assess the possible risk of false-negative examinations in patients thus treated. Analysis of the results indicated that among the four drugs tested, only methylprednisolone at 0.5–1 mg/kg could interfere with J001X scintigraphy.  相似文献   
998.
The authors describe three cases of partial complex epileptic seizures precipitated by alcohol consumption. No other causative factor was found. Brain imaging was normal. The role of alcohol in precipitating this type of seizures is discussed.  相似文献   
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