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81.
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
82.
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
83.
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
84.
Fredrik Ghosh Karl Engelsberg Robert V. English Robert M. Petters 《Albrecht von Graefes Archiv fur klinische und experimentelle Ophthalmologie》2007,245(6):835-846
Background The purpose of this study was to explore neuroretinal transplantation in a large animal model of severe retinitis pigmentosa
and to establish graft development, long-term survival, graft-host integration, and effects on the host retina.
Methods Rhodopsin transgenic pigs, aged 6 months, received in one eye a fetal full-thickness neuroretinal sheet in the subretinal
space by means of vitrectomy and retinotomy. Six months postoperatively, eyes were studied in the light microscope and with
immunohistochemical markers. Full-field electroretinography (ERG) was performed at 4 and 6 months.
Results Laminated grafts with well-organized photoreceptors, rod bipolar cells, and Müller cells were found in five of six eyes. Neuronal
connections between graft and host retina were not seen. In the five eyes containing a graft, the number of surviving rods
in the host retina was significantly higher compared with unoperated eyes. The ERG did not reveal any significant difference
in b-wave amplitude between operated and control eyes, but the cone-derived response in operated eyes increased significantly
from 4 to 6 months while the rod response in control eyes decreased significantly.
Conclusions Fetal full-thickness neuroretina can be transplanted safely to an eye with severe retinal degeneration. In their major part,
the transplants develop a normal laminated morphology and survive for at least 6 months. Graft and host retinal neurons do
not form connections. Retinal function in the host is reduced initially by the surgical trauma, but the presence of a well-laminated
graft counteracts this effect and rescues rods from degeneration.
Supported by The Foundation Fighting Blindness (grant# C-NC02-798-0078), The Faculty of Medicine, University of Lund, The
Swedish Research Council, The Princess Margaretas Foundation for Blind Children, The 2nd ONCE International Award for New
Technologies for the Blind. 相似文献
85.
视网膜缺血对兔视神经纤维损害的定量研究 总被引:2,自引:0,他引:2
目的:定量研究视网膜缺血对视神经的损害。方法:通过计算机图像分析定量测算视神经纤维数量;通过前房灌注平衡液,造成超高眼压,形成兔视网膜完全缺血模型,观察视神经纤维数量的变化。结果:正常兔眼平均视神经轴突数为109608±14561(n=22);视网膜缺血眼视神经纤维数量明显减少(P〈0.001)。结论:急性高眼压造成的视网膜缺血可使视神经节细胞及轴突的数量明显减少,应用计算机图像分析可定量检测这种 相似文献
86.
预变神经段修复神经缺损的实验研究 总被引:5,自引:2,他引:3
目的探讨不同预变时间组移植神经对神经再生的影响。方法以SD大鼠的不同预变时间组的尺神经作为移植神经,修复其正中神经的缺损。实验侧按移植神经预变时间的不同分为0、1、2、3、4、8周共6组,每组6只SD大鼠。移植后12周,检测实验侧趾屈肌群的张力、最大收缩力、再生神经的形态及神经轴突的截面积。结果用预变1周的尺神经修复正中神经后,其趾屈肌群的张力及最大收缩力的恢复率达到正常对照组的81.1%及85.9%。显微镜下观察,预变1周组和其它各时间组相比,其再生的神经轴突最多,发育最成熟。结论用预变1周的神经段修复神经缺损,其神经再生能力最佳 相似文献
87.
Toshio Mizutani Ken-ichi Nakamura Mutsuo Enomoto Masuhiro Sakata Shigeo Yamada 《Neuropathology》1998,18(1):80-90
A neuropathological study on 1540 consecutive autopsy brains ranging from 60 to 107 years of age revealed the following points. (1) Of the of the demented cases of the plaque-predominant type, 93% were complicated with multiple tiny cortical infarcts. They showed a tendency for dementia to develop before or after the appearance or worsening of a systemic disorder such as cardiovascular disease, respiratory infection and cancer. However, there was no case showing Alzheimer-type dementia (ATD). (2) The plaque-predominant type might be an extreme condition of brain aging in terms of senile plaques (SP). It is likely that although the pathological appearance of SP alone is not responsible for dementia, its coexistence with multiple cortical infarcts could be the cause of dementia. Therefore, this type should be distinguished from ATD. (3) Primary hippocampal degeneration could also be an extreme condition of brain aging in terms of neurofibrillary tangles. This condition was different pathologically from the hippocampal lesion in ATD. (4) Several characteristics of old-old and oldest-old patients were clarified. 相似文献
88.
89.
T. Mizutani S. Sakamaki N. Tsuchiya S. Kamei H. Kohzu R. Horiuchi M. Ida R. Shiozawa T. Takasu 《Acta neuropathologica》1992,84(4):372-377
Summary We describe two patients with sporadic amyotrophic lateral sclerosis (ALS), who had developed progressive external ophthalmoplegia of a predominantly supranuclear type while they survived on respirators, and displayed histopathological abnormalities both typical and atypical of ALS. Patient 1 was a 43-year-old man with ALS of 5-year duration, who had initially exhibited fulminant ALS, and remained on a respirator for 4 years. Patient 2 was a 51-year-old man with ALS of 13-year duration, who remained on a respirator for 8 years. Both patients died in a totally locked-in state. Autopsy of both patients revealed not only histopathological abnormalities consistent with ALS, but also multisystem degeneration which involved the pontine tegmentum, substantia nigra, Clarke's dorsal nuclei and spinocerebellar tracts. In addition, Patient 2 displayed intracyto-plasmic neuronal basophilic inclusion bodies which exhibited marked immunoreactivity to anti-ubiquitin antibodies. Our case reports indicate that the longer survival which is possible through the use of respirators may make one subgroup of ALS patients prone to develop atypical clinical and neuropathological features which are not observed during the natural cours of ALS.Supported by a Grant-in-Aid from the Research Committee of CNS Degenerative Diseases, the Ministry of Health and Welfare of Japan, and by a Grant from Nihon University School of Medicine, Tokyo 相似文献
90.
E V Famiglietti 《The Journal of comparative neurology》1992,324(3):295-321
The morphology and dendritic branching patterns of retinal ganglion cells have been studied in Golgi-impregnated, whole-mount preparations of rabbit retina. Among a large number of morphological types identified, two have been found that correspond to the morphology of ON and ON-OFF directionally selective (DS) ganglion cells identified in other studies. These two kinds of DS ganglion cell are compared with each other, as well as with examples of class I, class II, and class III cells, defined here with reference to our previous studies. Cell body, dendritic field size and branching pattern are analyzed in this paper and levels of dendritic stratification are examined in the following paper. ON DS ganglion cells are about 10% larger in soma size and about 5 times the dendritic field area of ON-OFF DS ganglion cells, when compared at the same retinal location. These two morphological types of ganglion cell can be said to define the upper and lower bounds of an intermediate range of cell body and dendritic field sizes within the whole population of ganglion cells. Nevertheless, in previous physiological studies receptive field sizes of the two types were shown to be similar. This discrepancy between morphological and physiological evidence is considered in the Discussion in terms of a model of the excitatory receptive field of ON-OFF DS ganglion cells incorporating starburst amacrine cells. A new set of metrics is introduced here for the quantitative analysis and characterization of the branching pattern of neuronal arborizations. This method compares the lengths of terminal and preterminal dendritic branches (treated separately), as a function of the distances of their origins from the soma, viewed graphically in a two-dimensional scatter plot. These values are derived from computer-aided 3D logging of the dendritic trees, and distance from the soma is measured as the shortest distance tracked along the dendritic branches. From these metrics of the "branch length distributions," scale-independent branching statistics are derived. These make use of mean branch lengths and distances, slopes of lines fitted to the distributions, and elliptical indices of scatter in the distributions. By these measures, ON and ON-OFF DS ganglion cells have similar branching patterns, which they share to varying degrees with functionally unrelated class III.1 ganglion cells. The scale of the branching patterns of ON and ON-OFF DS cells and their degree of uniformity are different, however.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献