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1.
The human visual system is amenable to a number of adaptive processes; one such process, or collection of processes, is the adaptation to blur. Blur adaptation can be observed as an improvement in vision under degraded conditions, and these changes occur relatively rapidly following exposure to blur. The potential important future directions of this research area and the clinical implications of blur adaptation are discussed. 相似文献
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3.
Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
4.
Serum ionic fluoride levels in haemodialysis and continuous ambulatory peritoneal dialysis patients 总被引:1,自引:1,他引:0
al-Wakeel JS; Mitwalli AH; Huraib S; al-Mohaya S; Abu-Aisha H; Chaudhary AR; al-Majed SA; Memon N 《Nephrology, dialysis, transplantation》1997,12(7):1420-1424
High serum fluoride (F-) in patients with chronic renal failure (CRF) and
end-stage renal disease (ESRD) is associated with risk of renal
osteodystrophy and other bone changes. This study was done to determine F-
in normal healthy controls and patients with ESRD on haemodialysis (HD) or
peritoneal dialysis (PD). Seventeen healthy controls (12 males, 5 females)
and 39 ESRD patients on dialysis (17 males, 22 females) were recruited in
the study in a community with 47.4 +/- 3.28 microM/l (range 44-51 microM/l)
of F- content in drinking water. Control subjects showed a mean serum F-
concentration of 1.08 +/- 0.350 microM/l. Males in control group showed
slightly higher F- levels (1.15 +/- 0.334, range 0.55-1.9 microM/l) than
females (0.92 +/- 0.370, range 0.6-1.5 microM/l). Mean serum F-
concentration did not correlate significantly with age and sex among
control subjects, whereas such correlation was observed in patients with
ESRD on dialysis. Mean serum F- concentration was significantly higher in
patients on dialysis (2.67 +/- 1.09, range 0.8-5.2 microM/l) than normal
controls. When grouped according to sex, the mean serum F- concentration in
males (3.05 +/- 1.04, range 1.8-5.2 microM/l) was significantly higher than
females (2.38 +/- 1.08, range 0.8-5.2 microM/l). When patients were grouped
according to age, it was observed that F- concentration was significantly
higher in patients with age groups 21-70 (2.86 +/- 1.05) than those with
age group 13-20 years (1.42 +/- 0.531). Thus F- concentration correlated
with age and sex, being higher in males and above 20 years. Despite
appreciable clearance of F- (39-90%) across the peritoneum, patients on
CAPD showed higher serum F- concentration than those on HD (3.1 +/- 1.97 vs
2.5 +/- 1.137 microM/l). Of the total 39 patients on dialysis 39% had their
serum F- concentration above 3.0 microM/l, posing the risk of renal
osteodystrophy.
相似文献
5.
Focal liver lesions: characterization with triphasic spiral CT 总被引:15,自引:1,他引:14
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7.
Metabolic adaptation of the chick embryo to chronic hypoxia 总被引:1,自引:0,他引:1
8.
The CTLA-4 gene region of chromosome 2q33 is linked to, and associated with, type 1 diabetes. Belgian Diabetes Registry 总被引:8,自引:1,他引:8
Nistico L; Buzzetti R; Pritchard LE; Van der Auwera B; Giovannini C; Bosi E; Larrad MT; Rios MS; Chow CC; Cockram CS; Jacobs K; Mijovic C; Bain SC; Barnett AH; Vandewalle CL; Schuit F; Gorus FK; Tosi R; Pozzilli P; Todd JA 《Human molecular genetics》1996,5(7):1075-1080
Susceptibility to autoimmune insulin-dependent (type 1) diabetes mellitus
is determined by a combination of environmental and genetic factors, which
include variation in MHC genes on chromosome 6p21 (IDDM1) and the insulin
gene on chromosome 11p15 (IDDM2). However, linkage to IDDM1 and IDDM2
cannot explain the clustering of type 1 diabetes in families, and a role
for other genes is inferred. In the present report we describe linkage and
association of type 1 diabetes to the CTLA-4 gene (cytotoxic T lymphocyte
associated-4) on chromosome 2q33 (designated IDDM12). CTLA-4 is a strong
candidate gene for T cell- mediated autoimmune disease because it encodes a
T cell receptor that mediates T cell apoptosis and is a vital negative
regulator of T cell activation. In addition, we provide supporting evidence
that CTLA-4 is associated with susceptibility to Graves' disease, another
organ- specific autoimmune disease.
相似文献
9.
Vascular adhesion molecules in vitreous from eyes with proliferative diabetic retinopathy. 总被引:15,自引:0,他引:15
G A Limb J Hickman-Casey R D Hollifield A H Chignell 《Investigative ophthalmology & visual science》1999,40(10):2453-2457
PURPOSE: To investigate whether proliferative vitreoretinopathy (PDR) is associated with a selective increase in vitreous levels of soluble vascular cell adhesion molecules that mediate leukocyte extravasation and interaction with endothelium during processes of inflammation and neovascularization. METHODS: Vitreous from 55 patients undergoing vitrectomy for treatment of PDR complicated by vitreous hemorrhage and/or traction retinal detachment was assayed for the presence of the soluble vascular cell adhesion molecules sICAM-1, sVCAM-1, and sE-selectin using a standard enzyme-linked immunosorbent assays (ELISA). Vitreous from 12 cadaveric eyes matching age and sex of the patients were used as control samples. RESULTS: Vitreous levels of sICAM-1, sVCAM-1, and sE-selectin were significantly higher in eyes with PDR than in control cadaveric vitreous, and levels of all three molecules did not relate to the type or duration of diabetes mellitus. However, eyes with either traction retinal detachment alone or both traction retinal detachment and vitreous hemorrhage exhibited significantly higher levels of sICAM-1 and sE-selectin than eyes with vitreous hemorrhage alone. Vitreous levels of sVCAM-1 were similar in eyes with either vitreous hemorrhage or traction retinal detachment alone. CONCLUSIONS: The present observations suggest that molecular inflammatory mechanisms may contribute to processes of neovascularization and fibrosis observed in PDR, possibly not as the causative event, but as a result of endothelial, Müller, and retinal pigment epithelial cell activation. The results also indicate that retinal detachment amplifies the existing inflammation within the diabetic retina. Identification of any abnormalities in the production and control of specific adhesion molecules could have important implications in the design of new therapeutic regimens to treat and prevent this sight-threatening complication of diabetes mellitus. 相似文献
10.
Vitreous levels of intercellular adhesion molecule 1 (ICAM-1) as a risk indicator of proliferative vitreoretinopathy 总被引:2,自引:0,他引:2 下载免费PDF全文
AIM: To investigate whether high vitreous levels of the soluble intercellular adhesion molecule 1 (sICAM-1) may be related to clinical risk factors of proliferative vitreoretinopathy (PVR) and whether their measurement may serve as an additional risk indicator of this complication in eyes with rhegmatogenous retinal detachment (RRD). METHODS: Levels of sICAM-1 were measured by enzyme linked immunosorbent assays (ELISA) in vitreous from 36 eyes with RRD clinically considered to be at high risk of developing PVR (large retinal breaks, vitreous haemorrhage, long standing RRD, and previous vitreoretinal surgery). Levels of sICAM-1 in this group were compared with those in vitreous from 31 eyes with RRD without clinical risk factors for PVR, 32 eyes with established PVR and 10 eyes with macular holes. RESULTS: Vitreous from eyes with RRD at high risk of developing PVR contained significantly higher levels of sICAM-1 (range 6.1-97.7 ng/ml; Mann-Whitney test, p=0.0002) than those from eyes with RRD at low risk of developing this complication (range 4.8-17.7 ng/ml). Vitreous sICAM-1 levels in eyes with RRD at high risk of developing PVR were significantly lower than in eyes with established PVR (p=0.037), but higher than in eyes with macular holes (p <0.0001). Levels of sICAM-1 >/=15 ng/ml (3 x median of the levels present in control eyes) provide a useful cut off point for a highly specific test (96.7%) with high positive (91.6%) and negative (96.7%) predictive values, despite a relatively low sensitivity (30. 5%). CONCLUSIONS: The present findings suggest that laboratory measurement of sICAM-1 levels in vitreous from eyes with RRD may constitute an additional factor for identifying patients at high risk of PVR. Hence, determination of sICAM-1 levels may aid in the monitoring of patients likely to develop this complication and in the identification of patients who may benefit from adjuvant anti-inflammatory therapy. 相似文献