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排序方式: 共有10000条查询结果,搜索用时 15 毫秒
91.
Willing AE Othberg AI Saporta S Anton A Sinibaldi S Poulos SG Cameron DF Freeman TB Sanberg PR 《Brain research》1999,822(1-2):246-250
One of the major issues in neural transplantation is the low survival rate (<5%) of transplanted dopamine (DA) neurons [3]. Recently it has been shown that it is possible to enhance the survival of these neurons, which in turn may decrease the amount of tissue that is required for each transplantation patient. The present paper demonstrates a novel approach for enhancing neuronal survival by co-transplantation of neuronal tissue with Testis-derived Sertoli cells (SC). This strategy could improve neuronal survival through the provision of trophic support. 相似文献
92.
Areas beyond the classical receptive field (CRF) can modulate responses of the majority of cells in the primary visual cortex of the cat (). Although general characteristics of this phenomenon have been reported previously, little is known about the detailed spatial organization of the surrounds. Previous work suggests that the surrounds may be uniform regions that encircle the CRF or may be limited to the "ends" of the CRF. We have examined the spatial organization of surrounds of single-cell receptive fields in the primary visual cortex of anesthetized, paralyzed cats. The CRF was stimulated with an optimal drifting grating, whereas the surround was probed with a second small grating patch placed at discrete locations around the CRF. For most cells that exhibit suppression, the surrounds are spatially asymmetric, such that the suppression originates from a localized region. We find a variety of suppressive zone locations, but there is a slight bias for suppression to occur at the end zones of the CRF. The spatial pattern of suppression is independent of the parameters of the suppressive stimulus used, although the effect is clearest with iso-oriented surround stimuli. A subset of cells exhibit axially symmetric or uniform surround fields. These results demonstrate that the surrounds are more specific than previously realized, and this specialization has implications for the processing of visual information in the primary visual cortex. One possibility is that these localized surrounds may provide a substrate for figure-ground segmentation of visual scenes. 相似文献
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L Cheng K Y Hostetler S Chaidhawangul M F Gardner U Ozerdem G Bergeron-Lynn B Mach-Hofacre A J Mueller G M Severson W R Freeman 《Retina (Philadelphia, Pa.)》1999,19(4):325-331
PURPOSE: To evaluate the clinical treatment efficacy of a long-lasting intravitreous injectable anti-cytomegalovirus (CMV) liposomal drug, 1-O-octadecyl-sn-glycerol-3-phosphonoformate (ODG-PFA). METHODS: Sixty-four pigmented rabbits were used for evaluation of the potency and duration of action of ODG-PFA after intravitreal injection using a herpes simplex virus (HSV)-1 retinitis model. For the potency evaluation, liposomal ODG-PFA was injected into rabbit vitreous at the same time that HSV-1 virus was inoculated onto the retina (simultaneous treatment). For the duration evaluation, ODG-PFA was injected days or weeks before inoculation (pretreatment). Retinitis was clinically graded by indirect ophthalmoscopy, and the retinitis scores were compared across the treatment and control groups. RESULTS: Simultaneous treatment study revealed that ODG-PFA was much more potent than its parent compound, foscarnet (P = 0.0027). Pretreatment study indicated that ODG-PFA possesses a much longer antiviral effect (at least 2 weeks) than foscarnet after a single intravitreal injection. CONCLUSION: Liposomal ODG-PFA is a potent long-lasting intravitreal injectable antiviral compound that may be an ideal alternative for treatment of CMV retinitis in patients with acquired immunodeficiency syndrome. 相似文献
97.
PURPOSE: A visual pattern was broken into patches, some of which were shown to one eye and the remainder of which were shown to the other eye. Our aim was to find the conditions under which the subject could combine the information given to the two eyes separately to reconstruct the original pattern. METHODS: One green and four red patches were presented to one eye. Five patches were presented to the other eye at corresponding locations but with red substituted for green and green for red. RESULTS: When the chromatic contrasts were appropriately adjusted, subjects saw five patches of a single colour for most of the viewing time. Intermixed horizontal and vertical gratings did not separate into coherent percepts in the same way. CONCLUSIONS: This result indicates cooperation between the responses to colour patches presented to different eyes, a finding that may be of use in testing for normal binocular vision. 相似文献
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Effect of montelukast on the pharmacokinetics and pharmacodynamics of warfarin in healthy volunteers
Van Hecken A Depré M Verbesselt R Wynants K De Lepeleire I Arnout J Wong PH Freeman A Holland S Gertz B De Schepper PJ 《Journal of clinical pharmacology》1999,39(5):495-500
Montelukast, a cysteinyl leukotriene receptor antagonist, is being developed for the treatment of asthma and related diseases. This study was designed to evaluate whether montelukast at clinically used dosage levels would interfere with the anticoagulant effect of warfarin. In a two-period, double-blind, randomized crossover study, 12 healthy male subjects received a single oral dose of 30 mg warfarin on the 7th day of a 12-day treatment with montelukast, 10 mg daily by mouth, or a placebo. Montelukast had no significant effect on the area under the plasma concentration-time curves and peak plasma concentrations of either R- or S-warfarin. However, slight but statistically significant decreases in time to peak concentration of both warfarin enantiomers and in elimination half-life of the less potent R-warfarin were observed in the presence of montelukast. These changes were not considered as clinically relevant. Montelukast had no significant effect on the anticoagulant effect of warfarin, as assessed by the international normalized ratio (INR) for prothrombin time (AUC0-144 and INR maximum). The results of this study suggest that a clinically important interaction between these drugs is unlikely to occur in patients requiring concomitant administration of both drugs. 相似文献
100.
Mark T. Jennings Michael L. Freeman Michael J. Murray 《Journal of neuro-oncology》1996,28(2-3):207-222
This article will review the current treatment of pediatric patients with diffuse pontine gliomas (DPG) and discuss three potential avenues of therapeutic research including (i) radiotherapy (RT) in combination with radiation sensitizers, (ii) dose-intensive, induction chemotherapy with hematopoietic support followed in sequence with RT applied as a consolidation therapy, and (iii) the interleafed application of phase-specific chemotherapeutic agents and hyperfractionated external beam radiotherapy (HFEBRT) referred to as chemoradiotherapy. 相似文献