以PowerPoint为平台制作眼科系列多媒体课件在眼科教学中的应用

通过多媒体技术在眼科教学中的应用,分析了开展多媒体教学的优势和存在的问题。     

Hydrocortisone delivery to healthy and inflamed eyes using a micellar polysorbate 80 solution or albumin nanoparticles

Hydrocortisone was loaded onto albumin nanoparticles by sorption. Two systems were tested, one comprised of a 0.03% saturated drug solution, the other of a 0.2% micellised drug solution. In both cases 45–70% of the originally available drug was bound to the carrier surface. The systems were further tested by measuring the in vitro transport of radiolabelled hydrocortisone through porcine cornea. Nanoparticles led to sustained drug transport through the cornea. The distribution of both 0.2% hydrocortisone preparations (nanoparticles and solution) was then evaluated under in vivo conditions in healthy and inflamed eyes of rabbits. In all tissues the level of drug was higher in the inflamed than in the healthy eye due to increased cell permeability as a result of inflammatory processes. The application of nanoparticles led to lower hydrocortisone tissue concentrations than the reference solution due to the strong binding of hydrocortisone onto the particle system and the resulting slow release. An exception occurred with the reference solution in the conjunctiva, as less drug was found in the inflamed than in the normal tissue, since enhanced lacrimation led to increased drug drainage. In contrast, the corresponding nanoparticle preparation was more efficiently retained at the inflamed than at the normal conjunctiva. Consequently, in the inflamed eye, hydrocortisone-loaded nanoparticles enabled targeting to the precorneal area away from the inner segments of the eye.     

D.B. Kagenaar and the ophthalmometer by Javal-Schiøtz

In the years 1881–1890 the Utrecht instrumentmaker D.B. Kagenaar, laboratory attendant of Donders and Snellen, played an important role in the introduction on the German market of the ophthalmometer developed by Javal and Schiøtz.     

眼科立体闪烁检查仪的研制

本文介绍一种眼科立体闪烁检查仪，由光学放大与立体视、频率可调照明和机械结构三部分构成。该仪能以立体闪烁的表达形式早期发现眼底和角膜新生血管疾病的细微改变，并能监测和观察病变的细微动态变化     

Coenzyme dependency of alcohol dehydrogenase in the retina of the rat. IV. Retinol dehydrogenase (RDH) activity in the developing normal and retinitis rat retina, and the effect on enzyme activity of increasing concentrations of NAD or NADP

Retinol dehydrogenase activity has been determined in the developing normal, and retinitis, rat retina, using NAD and NADP as the coenzymes. Under the experimental conditions employed NADP increases RDH activity almost three-fold compared to NAD. Both types of retina reach peak activity around 3 weeks after birth. Thereafter enzyme activity falls off, particularly in the retinitis retina, the decrease being more marked when NADP is the enzyme. More importantly it has been shown that a quadrupling of NAD in the assay system increases RDH activity to NADP levels. The implications of these findings and their possible roles in vision are discussed.     

Composition of the rhodopsin-core obtained by proteolysis of retinal rod outer segments with papain, and its regenerability after photobleaching

Incubation of retinal rod outer segments with the proteolytic enzyme, papain, results in the removal of 36% of the polypeptide chain of rhodopsin leaving a residue, the absorption spectrum of which is identical to that of the parent molecule. When the rhodopsin residue is bleached by light and subsequently incubated with 11-cis retinal its original spectral properties can be regenerated. A substantial part of the rhodopsin molecule is therefore not involved in any way in the production of the characteristic absorption spectrum.Amino acid analysis reveals that the rhodopsin residue is richer in glycine, leucine, tryptophan, tyrosine, histidine and arginine than rhodopsin itself, but poorer in threonine, glutamate, alanine and lysine. The residue appears to contain all the tryptophan of rhodopsin: it also contains the carbohydrate moiety.The piece of rhodopsin removed by papain is considered to be on the outer surface of the disc membranes.     

Experimental lens-induced granulomatous endophthalmitis: preliminary histopathologic observations

An experimental lens-induced granulomatous endophthalmitis (ELGE), which histopathologically is virtually identical to the human phakoanaphylactic endophthalmitis (or lens-induced uveitis), was produced after injury to the lens in rats that had been previously sensitized to homologous lens protein in complete Freund's adjuvant. ELGE was not observed in four different groups of control animals. We believe, therefore, that this study provides direct evidence that ELGE is an immune reaction to autologous lens antigens in rats previously sensitized to homologous lens antigens.     

Ninth Annual Richard G. Scobee Memorial Lecture. Sensory response in exotropia.

The characteristics, methods of clinical investigation, and incidence of amblyopia, suppression, and anomalous retinal correspondence in exotropia have been reviewed from the ophthalmic literature. It is hoped that reemphasizing the sensory anomalies in exotropia may lead to more sensitive clinical investigation in these areas and, ultimately, to a better understanding of the sensory system and some of its enigmatic responses.     

Intensity discrimination capacity of retinal ganglion cells of a tree shrew ( Tupaia chinensis)

Responses of single retinal on-centre ganglion cells were recorded in order to study the intensity discrimination threshold behaviour. A Poisson distribution fitted pulse number distributions of the spikes in the burst evoked by short duration stimuli presented within the receptive field centre of sustained units. A normal distribution was found for transient units. The dependence of the mean, standard deviation and regularity of the pulse number distribution on stimulus intensity mimicked the behaviour of the statistical parameters of the maintained activity as a function of background intensity. The transient cells displayed statistical characteristics which are found also in psychophysical studies. These cells, therefore, are assumed to be mainly involved in intensity discrimination.The dynamic range of ganglion cells in response to short duration stimuli is relatively narrow, 1 log unit, so the Weber law which is valid over many log units cannot be explained with the single-channel detection model. A multichannel energy summation model yields a threshold curve that closely resembles psychophysically measured curves.The psychophysical dependency of the discrimination threshold on background intensity level as investigated by Thijssen and Vendrik (1971) could be explained from the responses of both types of cells.