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71.
M. Higashima Hiroya Kinoshita Nariyoshi Yamaguchi Yoshifumi Koshino 《Psychopharmacology》1997,131(4):394-398
It has been reported that the clinical and electroencephalographic profiles of zolpidem, a non-benzodiazepine drug which
binds preferentially to the ω1 benzodiazepine recognition sites located within the GABAA receptor complex, are different from those of benzodiazepine drugs, which bind non-selectively to the ω1 and ω2 sites. In order to clarify the electrophysiological mechanism underlying the unique profile of zolpidem, the present study
compared the enhancing effects of zolpidem and two benzodiazepine drugs, triazolam and diazepam, on recurrent inhibition.
This inhibition was expressed as suppression of the orthodromically induced population spikes by the preceding antidromic
stimulation of the alveus in the CA1 region of rat hippocampal slices. The rank order of potency for enhancing recurrent inhibition
was triazolam > diazepam > zolpidem. From the present results and previously reported findings that zolpidem has a lower affinity
for the ω2 sites than diazepam while both have the same affinity for the ω1 sites, we concluded that the hippocampal recurrent inhibition appears to be enhanced mainly by activation of the ω2 sites, but not by that of the ω1 sites. Furthermore, the lower potency of zolpidem for enhancing recurrent inhibition may underlie its unique profile in terms
of its clinical and electroencephalographic effects.
Received: 1 November 1996/Final version: 22 January 1997 相似文献
72.
实验性视网膜脱离Na十-K+-转运ATP酶活性及RPE超微结构改变 总被引:2,自引:1,他引:1
目的:探讨实验性视网膜脱离(retinal detachment,RD)后视网膜色素上皮(retinal pigment epithelium,RPE)对视网膜下液(subretinal fluid,SRF)的输导功能。
方法:将制作成功的实验性单眼RD 28只家兔随机分为4组,每组7只,每只兔的另眼作为对照。分别取RD部位的RPE-脉络膜组织和对照眼相应部位的组织匀浆,再测定ATP水解产物无机磷含量,以判断ATP酶活性;并作实验和对照眼的两种组织相应部位的RP正电镜观察。
结果:实验眼Na十-K+-转运ATP酶活性为(2.16士1.26)/μmol(mg·h),对照眼为(4.84±1.59)μmol/(mg·h),二者差异显著(t=5.52,P<0.01);酶活性降低程度随病程延长而减轻(p<0.05)。电镜观察实验眼RD后第2至4周有自脉络膜向视网膜方向的吞饮泡,且随病程延长而增多。
结论;RD发生后RPE的外向输导功能增强,随病程进展,此功能减弱而内向输导功能产生。
(中华眼底病杂志,1997,13:83-85) 相似文献
73.
Human gingival keratinocytes were cultured and, after the first passage, subjected to cell detachment assays with polymorphonuclear leucocytes (PMNs) and/or sonic extracts from Actinobacillus actinomycetemcomitans Y4, and Eikenella corrodens 1073. The effector-to-target cell ratio was 30:1. Bacterial extracts alone caused no disruption of keratinocyte monolayers. PMNs alone also caused only minimal detachment after 14 h incubation. Adding A. actinomycetemcomitans to the PMN-keratinocyte co-cultures at the concentration of 100 μg/ml caused dramatic cell detachment. The effect of A. actinomycetemcomitans was heat labile and not inhibited by polymyxin B. Cell detachment was inhibited by α1-antitrypsin, whereas catalase and Superoxide dismutase could not prevent it. No lysis of keratinocytes was observed after incubation, as judged by 51Cr release. E. corrodens had little effect even at the concentration of 1000 μg/ml. H2O2 and partially purified PMN elastase also caused detachment of keratinocytes. These data indicate that PMNs can cause non-lytic detachment of keratinocytes when interacting with certain bacteria. 相似文献
74.
We have performed molecular and mutation analyses on 14 unrelated Israeli Hunter families and have identified the IDS mutation in 8 of them. Three unrelated Ashkenazi patients had the same previously reported mutation (1246 C→T). Based on the haplotypes of the mutation-bearing chromosomes, we concluded that this is a recurrent mutation. In two patients, we identified a deletion spanning exons V–VII. Three novel mutations were observed in different patients: L410P, 717del4, and 244del3. In addition, the silent mutation (562 C→T) was observed in one patient. © 1994 Wiley-Liss, Inc. 相似文献
75.
目的探讨婴幼儿复发性喉乳头状瘤的观察与护理。方法对33例婴幼儿复发性喉乳头状瘤患儿密切观察病情,以赢取抢救机会;进行有效的术前术后护理,包括完善术前准备和进行术前护理评估及术后并发症的预防、气管切开术后呼吸道管理等。结果33例中31例均好转出院,2例病情变化抢救无效死亡。结论婴幼儿复发性喉乳头状瘤患儿的术前、术后观察与护理对及时发现患儿病情变化,进行有效的抢救措施至关重要。 相似文献
76.
本研究应用致敏红细胞花环试验法(间接法)对34名复发性口腔溃疡(ROU)患者溃疡期和缓解期及28名正常人外周血中的T细胞亚群进行了检测,以图了解ROU患者的细胞功能状态。结果显示:与正常对照组相比,在溃疡期,ROU患者外周血中的T3和T4值无明显变化;T8值明显升高;T4/T8比值明显降低。而在溃疡缓解期,ROU患者外周血中的T3、T4、T8值以及T4/T8比值与正常组相比例无明显差别。研究结果表 相似文献
77.
成人原发性肾病综合征患者尿视黄醇结合蛋白的测定及意义 总被引:2,自引:0,他引:2
采用酶联免疫法检测100例正常人及79例成人原发性肾病综合征治疗前后尿视内醇结合蛋白的变化。追踪随访2年,发现经治疗后病理类型为ECPGN,MCN,IgA GN者,尿蛋白及RBP均明显减少,其肾功能不全的发生率较低,而MGN,FSGS,SGN者,尿蛋白及RBP无明显减少,肾功能不全的发生率较高,MsPGN因其增生程度的不同,治疗效果及预后有所不同,轻度增生者治疗效果及预后较好,中,重度增生者,基 相似文献
78.
Retinal projections and visual thalamo-cortical connections were studied in the subterranean mole rat, belonging to the superspecies Spalax ehrenbergi, by anterograde and retrograde tracing techniques. Quantitative image analysis was used to estimate the relative density and distribution of retinal input to different primary visual nuclei. The visual system of Spalax presents a mosaic of both regressive and progressive morphological features. Following intraocular injections of horseradish peroxidase conjugates, the retina was found to project bilaterally to all visual structures described as receiving retinal afferents in non-fossorial rodents. Structures involved in form analysis and visually guided behaviors are reduced in size by more than 90%, receive a sparse retinal innervation, and are cytoarchitecturally poorly differentiated. The dorsal lateral geniculate nucleus, as defined by cyto- and myelo-architecture, cytochrome oxidase, and acetylcholinesterase distribution as well as by afferent and efferent connections, consists of a narrow sheet 3–5 neurons thick, in the dorsal thalamus. Connections with visual cortex are topographically organized but multiple cortical injections result in widespread and overlapping distributions of geniculate neurons, thus indicating that the cortical map of visual space is imprecise. The superficial layers of the superior colliculus are collapsed to a single layer, and the diffuse ipsilateral distribution of retinal afferents also suggests a lack of precise retinotopic relations. In the pretectum, both the olivary pretectal nucleus and the nucleus of the optic tract could be identified as receiving ipsilateral and contralateral retinal projections. The ventral lateral geniculate nucleus is also bilaterally innervated, but distinct subdivisions of this nucleus or the intergeniculate leaflet could not be distinguished. The retina sends a sparse projection to the dorsal and lateral terminal nuclei of the accessory optic system. The medial terminal nucleus is not present. In contrast to the above, structures of the “non-image forming” visual pathway involved in photoperiodic perception are well developed in Spalax. The suprachiasmatic nucleus receives a bilateral projection from the retina and the absolute size, cytoarchitecture, density, and distribution of retinal afferents in Spalax are comparable with those of other rodents. A relatively hypertrophied retinal projection is observed in the bed nucleus of the stria terminalis. Other regions which receive sparse visual input include the lateral and anterior hypothalamic areas, the retrochiasmatic region, the sub-paraventricular zone, the paraventricular hypothalamic nucleus, the anteroventral and anterodorsal nuclei, the lateral habenula, the mediodorsal nucleus, and the basal telencephalon. These results indicate that the apparently global morphological regression of the visual system conceals a selective expansion of structures related to functions of photoperiodic perception and photo-neuroendocrine regulation. We suggest that the evolution of an atrophied eye and reduced visual system is an adaptively advantageous response to the unique subterranean environment. Factors favoring regression include mechanical aspects, metabolic constraints, and competition between sensory systems. The primary advantage of sensory atrophy is the metabolic economy gained by the reduction of visual structures which do not contribute significantly to the animal's fitness. © 1993 Wiley-Liss, Inc. 相似文献
79.
K. M. Saari M.D. 《International ophthalmology》1986,9(1):45-60
To study the inheritance and clinical picture of a new form of vitreoretinal dystrophy I examined 18 family members of a family with six generations. Seven patients, three male and four female, in three consecutive generations were observed to be affected indicating autosomal dominant inheritance. The disease was characterized by juvenile degeneration of the vitreous with detachment of the vitreous body and some floating vitreous opacities, cystoid degeneration of the peripheral retina with whitish glistening stippled areas of superficial retinal degeneration, spotty hyperpigmentation, patches of retinal atrophy with pigmentations, occasional atrophic retinal holes, and in four family members at the age of 4 to 12 years, unilateral or bilateral retinal detachment with breaks in the peripheral retina. Most patients had hyperopia with or without astigmatism. In eyes without detached retina, the disease did not show any marked progression, the lens was clear, the posterior fundus and the retinal and choroidal vessels were normal, and the visual acuity, visual fields, dark adaptation, colour vision, electroretinograms, and visually evoked response findings were normal. 相似文献
80.
Antonio Fea Andrea Grosso Marilena Rabbione Federico Grignolo 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(2):315-317
Background Optic disc anomalies are frequently associated with Alagille syndrome. We report here the first case of a patient with Alagille
syndrome combined with optic pit and serous macular detachment.
Methods A male patient with Alagille syndrome was referred from the pediatric hepatology department for investigation of visual loss
in the right eye. Anterior segment examination showed evidence of posterior embryotoxon, confirmed by gonioscopic evaluation.
Dilated fundus examination revealed serous macular detachment and optic pit.
Results OCT 3 scans confirmed the clinical findings.
Conclusions Optic pit is uncommon and should prompt a search for genetic disorders or development abnormalities. The association between
the two syndromes in this patient might be due to failure of correct neuroectodermal development, for which a common genetic
pathway is likely. 相似文献