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31.
Choroidal neovascular membrane in Best's vitelliform macular dystrophy   总被引:2,自引:0,他引:2  
The right eye of a 9-year-old white boy with Best's vitelliform macular dystrophy had an intact egg-yolk lesion and a retinal pigment epithelial defect superiorly, suggesting an early pseudohypopyon stage. The disruptive phase of the left eye showed subretinal hemorrhages, a "signet ring," and a subretinal neovascular membrane.  相似文献   
32.
The pathway from the entorhinal cortical region to the hippocampal formation has previously been shown to be comprised of two sub-systems, one of which projects predominantly to the ipsilateral fascia dentata and regio inferior of the hippocampus proper, and a second which projects bilaterally to regio superior. The goal of the present investigation was to determine if these two pathways might originate from different cell populations within the entorhinal area. The cells of origin of these entorhinal pathways were identified by retrograde labeling with horseradish peroxidase (HRP). Injections which labeled the entorhinal terminal fields in both the fascia dentata and regio superior resulted in the retrograde labeling of two populations of cells in the entorhinal area. Ipsilateral to the injection, HRP reaction product was found in the cells of layer II (predominantly stellate cells) and the cells of layer III (predominantly pyramidal cells). Contralateral to the injections, however, the reaction product was found almost exclusively in the cells of layer III. With selective injections of the entorhinal terminal field in regio superior, only the cells of layer III were labeled, but these were labeled bilaterally. Selective injection of the entorhinal terminal field in the fascia dentata, however, resulted in the labeling of cells of layer II, but not of layer III, and these cells of layer II were labeled almost exclusively ipsilaterally. A very small number of labeled cells in layer II were, however, found contralateral to the injection as well. No labeled cells were found either in the presubiculum or parasubiculum following injections of the hippocampal formation. These cell populations were found capable of retrograde transport of HRP, however, since cells in both presubiculum and parasubiculum were labeled following HRP injections into the contralateral entorhinal area. These results suggest that the projections to the fascia dentata originate from the cells of layer II, while the projections to regio superior originate from the cells of layer III of the entorhinal region proper. The very slight crossed projection from the entorhinal area to the contralateral area dentata probably originates from the small population of cells in layer II which are labeled following HRP injections in the contralateral area dentata.  相似文献   
33.
The use of photodynamic dye and light inactivation for the treatment of genital herpes simplex virus infections has been associated with the risk of potential oncogenesis. Sixteen patients treated with neutral red and fluorescent light for documented herpetic infections were studied at intervals ranging from 9 to 52 months following treatment. Four patients treated with other modalities were included in the study. Biopsies of the treated areas were obtained, and 3925 tissue sections were examined. Mild atypical epithelial changes were focally present in most specimens regardless of therapy. Histologically identifiable premalignant change could not be demonstrated.  相似文献   
34.
Adrenergic receptors mediating depolarization in in vitro neonatal rat brown adipose tissue (BAT) have been characterized by use of adrenergic agonists and antagonists. Releasable endogenous catecholamine was present in BAT as demonstrated by tyramine- and 1,1-dimethyl-4-phenylpiperazinium iodide- (DMPP) induced depolarization in BAT from normal rats and its absence when BAT from reserpinized rats was used. In BAT from reserpinized rats l-norepinephrine, l-phenylephrine, and l-isoproterenol all similarly depolarized the bronw adipocytes over the concentration range of 10(-8) to 10(-6) M with a maximal depolarization of about 25 mV. Dopamine and d-norepinephrine were more than 100 times less potent. The beta-adrenergic blocker propranolol competitively inhibited isoproterenol-induced depolarization, whereas the alpha-adrenergic blackers, phentolamine and phenoxybenzamine, inhibited the phenylephrine-induced depolarization with much smaller inhibitory effects on the isoproterenol-induced depolarization. Both phenylephrine and isoproterenol elicited transient depolarizations when briefly added to the bathing medium while continuously recording from the same cell. Both the agonist and antagonist studies are interpreted as indicating the presence of both alpha- and beta-adrenergic receptors on BAT cells which mediate catecholamine-induced depolarization.  相似文献   
35.
112 patients with varicose small sephenous vein were operated upon. The operation was preceded by a careful clinical investigation, including phlebography. The observed changes were correlated with operative findings. It is shown that varicosity may be conditioned by an obstruction of blood outflow in the popliteal vein or small saphenous vein ostium. A relationship between some structural variants of the small saphenous vein and hemodynamic disturbances was noted.  相似文献   
36.
1 The mydriasis resulting from topical application of five atropine-like drugs was measured photographically in man. Drug potency was obtained from log dose-response curves. 2 The in vitro potency of eight cholinoceptor blocking drugs, including those studied in man, was obtained by measuring their affinity constants for binding to the receptors of an isolated preparation of the rabbit sphincter pupillae. Values agreed closely with those obtained for the muscarinic receptors of guinea-pig ileum. 3 In vitro and in vivo potency was compared to obtain a quantitative measure of the relative ease with which drugs gain access to the receptors after topical application. 4 The large differences that occur in the intensity and duration of the mydriatic response to atropine-like drugs is primarily the result of differences in their ability to blcok the receptors. Only with tropicamide does its relatively high accessibility affect its potency in man.  相似文献   
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The degradation and excretion of 2-14C-uric acid were examined in three adult woolly monkeys (Lagothrix lagothrichia) to determine the basis for the relatively high serum and urinary uric acid concentrations previously reported in this species. Like man and the great apes which lack uricase, but in distinction to most other mammals, these animals converted very little urate to allantoin. Uric acid turnover, as has been reported for other New World monkeys, was several times that of normal man. Renal urate excretion as well as disposition by extrarenal mechanisms may protect Lagothrix vrom hyperuricemia. The capacity to convert urate to allantoin appears to have been lost late in the evolution of New World monkeys. The woolly monkey deserves further study as a primate model for investigations of enzyme replacement strategies.  相似文献   
40.
Examined discrepancy scores (Verbal IQ minus Performance IQ) for the WISC-R, using the standardization sample--100 boys and 100 girls at each of 11 age levels between 61/2 and 161/2 yrs (2,200 Ss). The occurrence of significant discrepancy scores (Verbal > Performance and Performance > Verbal) was not significantly related to age, sex, or race, although significant relationships were obtained with both parental occupation and intelligence level. The mean absolute discrepancy score (regardless of sign) was about 10 IQ points for each age group, for boys and girls, for Blacks and Whites, and for the different occupational groups. Discrepancy score norms (cumulative distributions) are presented by intelligence level and are interpreted in terms of their clinical significance. Several of these findings closely parallel results of a study of the 1949 WISC by H. G. Seashore (see record 1952-06292-001). (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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