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21.
G J Jaffe T C Burton E Kuhn A Prescott A Hartz 《American journal of ophthalmology》1992,114(4):448-456
Twenty-one patients with symmetric nonproliferative retinopathy who underwent extracapsular cataract extraction and intraocular lens implantation were followed up postoperatively for an average (+/- standard deviation) of 18 +/- 7 months to determine the incidence of progression of diabetic retinopathy, the final visual acuity, and factors predictive of progression of retinopathy and final visual acuity. Progression of retinopathy, defined as the development of clinically significant macular edema, an increase in intraretinal hemorrhages or hard exudate, or the development of proliferative diabetic retinopathy, was assessed in both eyes of 19 patients; in two remaining patients, dense preoperative cataract in the fellow eye precluded comparison of retinopathy progression in the operated-on eye to progression in the fellow eye. Overall, retinopathy progressed in 14 of 19 operated-on eyes (74%). Cataract extraction was highly associated with asymmetric progression of nonproliferative retinopathy; it progressed only in the operated-on eye in seven of 19 patients (37%), but in no patients did progression occur in the fellow eye alone (P = .0078). Women had a significantly increased risk of progression of retinopathy in the operated-on eye compared to men (P = .005). Visual acuity improved in 19 of 21 operated-on eyes (86%); however, only 11 eyes (52%) achieved a visual acuity of 20/50 or better and only six eyes (14%) achieved a visual acuity of 20/25 or better. In only five eyes was the final visual acuity in the operated-on eye more than two lines better than the final visual acuity in the fellow eye.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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The release of endogenous DA and DOPAC from nucleus accumbens slices were studied measuring net outflow of DA and DOPAC in the superfusate of static chambers, to analyze the correlation between DA and DOPAC outflows and identify which DA stores may serve as possible sources for DOPAC formation. Under resting conditions, or following stimulation with low (< 15 mM) KCl concentration, DOPAC outflow was greater than DA. When DA release was stimulated by higher (> 25 mM) KCl concentrations, DA outflow increased, proportionally more than DOPAC. In the virtual absence of Ca2+ in the Krebs solution DA outflow, induced by 25 mM KCl, was reduced to about 10%, while DOPAC outflow was only reduced to 45%. When the synthesis of DA was inhibited with -MPT, DA and DOPAC outflow were unchanged during the first stimulation period. During a second stimulation period, however, their outflow were significantly reduced. Nomifensine, a DA uptake inhibitor, increased the basal DA outflow by about 100%, but only blocked DOPAC basal outflow by about 25%. The 25 mM KCl stimulated DA outflow was not affected by Nomifensine, while the stimulated DOPAC outflow was reduced by about 50%. These results demonstrate that there is a weak correlation between the outflows of DA and DOPAC, suggesting a complex relationship between the mobilization of the different DA pools and DOPAC outflow. The formation of DOPAC from some of these pools, appear to be dependent on the stimulation levels and on the pharmacological manipulation of the tissue. 相似文献
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Comparative study of brain morphology in ants 总被引:1,自引:0,他引:1
Brain morphology, with special attention to the three dimensional form of the corpora pedunculata, was studied in thirteen species of ants, representing four subfamilies of Formicidae. The results can be summarized as follows. (1) The neural systems processing optic and olfactory information differ in the evolutionary history among the studied taxa. A positive correlation can be demonstrated in the phylogenetic history of the corpora pedunculata, central body, cerebral bridge and olfactory lobe, but not the optic lobe. Ant species with very large eyes and thus, probably, highly developed vision, show gigantic optic lobes, with no exaggeration of any other brain structure. (2) More social species have more complex chemical communication systems and better developed corpora pedunculata (more surface in foldings of the calyces) and olfactory lobes; however, this tendency seems to reverse in highly social species with a sophisticated polymorphic caste system: individuals of these species are generally less developed neurally. (3) There are differences between the form of the internal and external calyces of the corpora pedunculata, and these differences are proportionately more pronounced in species with complex social organization. (4) Individuals from different worker castes of the same species differ in their brain morphology, but each species shows a different pattern of variation among their castes. (5) Brain structure shows characteristic marks due to the different phylogenetic developments in the taxa studied. For example the trends in brain volume-body size ratio are different for the various subfamilies, suggesting a divergent phylogenetic history. 相似文献
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Use of purified parasite proteins from Leishmania donovani for the rapid serodiagnosis of visceral leishmaniasis 总被引:12,自引:0,他引:12
Serodiagnosis of visceral leishmaniasis (VL) due to Leishmania donovani by using crude parasite antigen is complicated in many endemic areas because of cross-reactions with sera from humans with Chagas' disease. We used affinity-purified parasite proteins to develop a direct dot-blot assay for VL. Double-blind tests were carried out on sera from 40 patients with well-documented VL, from controls in endemic areas, and from patients with other diseases. Using gp70-2, 36 (90.0%) of 40 sera from patients with kala azar were correctly diagnosed; 1 (1.2%) of 86 sera from patients without kala azar was misdiagnosed. With dp72, 21 (100%) of 21 sera from patients with VL were correctly identified; 5 (7.0%) of 71 negative sera were misdiagnosed. None of the 18 sera from patients with Chagas' disease reacted positively against gp70-2. Our assay is rapid, simple, and specific and represents a new method for reliably diagnosing and monitoring VL. 相似文献
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Psychoses due to thyrotoxicosis are typically affective in nature. We report on a schizophreniform psychosis in a woman with Graves' disease whose symptoms abated following subtotal thyroidectomy. Surgical thyroidectomy should be considered in thyrotoxic patients who are unresponsive to medical therapy or who manifest unremitting or life-threatening psychotic behavior, especially if long-term compliance required for medical therapy appears unlikely. 相似文献
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Intestinal obstruction proximal to a transition zone without an interposed physical barrier usually indicates Hirschsprung disease. The authors report one case of focal small bowel muscular thinning just distal to a transition zone that produced clinical and radiographic findings that simulated long-segment Hirschsprung disease in a 2-day-old infant. 相似文献