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61.
Mirjam Gross-Jendroska Christina J Flaxel Steve D Schwartz Frank G Holz Fred W Fitzke Veit-Peter Gabel Alan C Bird 《Clinical & experimental ophthalmology》1998,26(4):311-317
Purpose: To flatten pigment epithelial detachments (PED) cue to age-related macular degeneration in an attempt to visualize the underlying choroidal neovascularization by fluorescein angiography (FA) and reveal a treatment target. Methods: Nine patients with PED received intravitreal gas injections via the pars plana and postured face down. Fluorescein angiograms were obtained before and after gas injection. In two patients, retinal scotopic sensitivity was also measured. Results: Eight patients demonstrated change in the shape and size of the PED following gas injection. Four patients showed a better delineation of underlying structures on FA. Three patients had focal laser treatment to the newly visible choroidal neovascular complex, but this was successful in only one patient with flattening of the PED. Conclusion: Pigment epithelial detachments can be modified by intravitreal gas injection in some patients, but this treatment did not have a major impact on overall outcome or management. 相似文献
62.
Transection of an optic nerve (ON) is followed by slow removal of myelin. We studied microglia for the expression of molecules that characterize activated myelin phagocytosing macrophages: MAC-1, FcγII/III receptor (FcR), MAC-2, and F4/80. In-vitro, microglia expressed all molecules and phagocytosed myelin. In-vivo, intact ON displayed high levels of MAC-1, little FcR and F4/80, and no MAC-2. The expression of these molecules was upregulated differentially in in-vivo degenerating ON: MAC-1 uniformly, FcR and F4/80 variably, and MAC-2 sporadically. The distribution of MAC-2 expression correlated best with a pattern of sporadic structural degeneration. Thus in-vivo, ON injury is followed by deficient microglia activation, which we suggest contributes significantly to the slow clearance of myelin. 相似文献
63.
老年黄斑变性的视网膜色素上皮及其视功能的改变 总被引:2,自引:0,他引:2
目的:应用黄斑区密集点矩阵视野并结合眼底荧光血管造影电脑眼底图像分析老年黄斑变性视网膜色素上皮损害与DMMM的视野光敏感度的改变,找出改变的规律有评价其应用价值。方法:用Humphrey-640视野计自行设计DMMM检测AMD干性组51人64只眼湿性且23人27只眼,用Zeiss公司生产的KONTRONELEKTRONIK Inage Analysis Division-计算机图像分析仪总丢失量显 相似文献
64.
Emine Sözeri Dietrich Feist Hans Ruder Karl Schärer 《Pediatric nephrology (Berlin, Germany)》1997,11(3):307-311
Renal lesions have repeatedly been described in Wilson’s disease (WD). We investigated the excretion of total protein, albumin,
low (LMW) and high molecular weight (HMW) proteins, N-acetyl-β-D-glucosaminidase (NAG), and calcium, as well as creatinine clearance, in 24-h urine samples of 41 patients with WD aged 6 – 37
(mean 17) years who had been treated for a period of 0 – 15 (mean 4.5) years with D-penicillamine (900 mg/day). The amount of all protein excreted was significantly increased compared with controls, 39% of
patients presenting with total proteinuria more than two standard deviations from the mean of controls. The changes in protein
excretion depended on the duration of treatment. LMW proteinuria was elevated almost exclusively in the first 2 years after
the start of treatment, indicating early tubular damage. This is supported by an initially high excretion of β2-microglobulin, NAG, and calcium. Increased excretion of HMW proteins, including albumin, persisted over longer periods, which
suggests glomerular injury in some patients, possibly related to the use of D-penicillamine. Creatinine clearance remained roughly within normal limits. We propose that renal function should regularly
be checked in patients with WD.
Received October 26, 1995; received in revised form August 27, 1996; accepted September 20, 1996 相似文献
65.
Summary. A prevalence study of Ureaplasma urealyticum (UU) infection of the male genital tract was carried out in Shanghai between March 1992 and June 1995. Significantly higher frequency of UU infection was found among infertile males (549/1416) as compared to fertile controls (34/375). Examination of 8 specimens each from infertile men and fertile subjects by electron microscopy, immunogold and immunofluorescence techniques, demonstrated adhesion of Ureaplasma urealyticum to the membrane of spermatozoa and exfoliated germ cells. In addition, gold particles on Ureaplasma urealyticum were found to be adhered to the sperm surface in 4 of the 8 samples. Strong specific anti-UU fluorescence was detected in 6 of 8 samples, mainly on the midpieces and post-acrosomal regions of the spermatozoa.
To further study the effects of Ureaplasma urealyticum on fertility, 47 male Sprague-Dawley (SD) rats were infected artificially with Ureaplasma urealyticum serotype 8 (T960). Morphological changes in the seminiferous tubules were observed 3–5 weeks after inoculation in the sacrificed animals. Dramatic impairment of spermatogenesis of both testes was found in 11 rats. Mating experiment confirmed infertility in 12 of 40 rats. Offsprings of the infected rats were significantly smaller than those of controls in terms of prenatal weights and birthweights. 相似文献
To further study the effects of Ureaplasma urealyticum on fertility, 47 male Sprague-Dawley (SD) rats were infected artificially with Ureaplasma urealyticum serotype 8 (T960). Morphological changes in the seminiferous tubules were observed 3–5 weeks after inoculation in the sacrificed animals. Dramatic impairment of spermatogenesis of both testes was found in 11 rats. Mating experiment confirmed infertility in 12 of 40 rats. Offsprings of the infected rats were significantly smaller than those of controls in terms of prenatal weights and birthweights. 相似文献
66.
67.
目的:以骨髓间充质干细胞作为种子细胞,探索组织工程化软骨的构建.方法:分离、获取、扩增骨髓间充质干细胞,通过将扩增的骨髓间充质干细胞接种于聚羟基乙酸(PGA)上,在成软骨诱导因子作用下在体外诱导培养3周后,将实验组和对照组的标本转植入自体兔腹腔内,进行体内培养6~12周后,再进行检测,评估工程化软骨的形成.结果:骨髓间充质干细胞接种于PGA支架上后,经过体外诱导培养和体内培养后,获得标本(7/10)出现软骨组织外观,进行组织学切片可见软骨陷窝,进行Ⅱ型胶原蛋白的免疫组化、Ⅱ型胶原mRNA原位杂交均为阳性.结论:兔骨髓间充质干细胞在成软骨诱导剂作用下,经体外和体内培养后,可生成组织工程化类软骨. 相似文献
68.
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
69.
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
70.
W. Gubisch 《European journal of plastic surgery》1993,16(3):125-129
Summary Traumatic defects of the auricle are quite common. The eventual success of the repair is considerably influenced by the initial treatment. The different parts of the auricle require different approaches. This paper presents our methods for repairing damage to the cartilaginous frame using autologous ear cartilage grafts, and local flaps from the mastoid region to cover soft tissue defects. 相似文献