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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
2.
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
6.
Metabolic adaptation of the chick embryo to chronic hypoxia 总被引:1,自引:0,他引:1
7.
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
8.
The data support the role of seminal plasma facilitating the transmission of virus and establishment of infection when all depositions of semen occur, but systemic absorption would also be possible by vaginal intercourse if lesions or abrasions caused for example by other s.t.d's, were present. The severity and rapid increase in the population of certain sexually transmitted agents make it imperative that epidemiological studies are initiated to study any correlation with changes in sexual behaviour and contraceptive practices. Finally, further isolation and characterization of seminal plasma components should lead to a clear understanding of their action as both regulatory molecules and in their possible contribution to disease. 相似文献
9.
In this paper we report studies undertaken to determine the contribution of seminal prostaglandins to some of the known immunosuppressive properties of human seminal plasma. Initial studies revealed that fractions of seminal plasma enriched in E series prostaglandins, obtained by reverse phase chromatography, had a pronounced inhibitory effect on the PHA-induced proliferation of peripheral blood lymphocytes and on the NK-cell-mediated lysis of K562 target cells. Additional investigations revealed that similar inhibitory effects could be achieved with purified PGE2 (10(-6) to 10(-9) M) and 19-OH PGE1 (10(-6) to 10(-7) M), both of which are present in uniquely high concentrations in human seminal plasma. In contrast, 19-OH PGF1 which is found in lower concentrations in semen was slightly stimulatory in proliferative assays and had no effect on NK-cell-mediated cytotoxicity. Removal of the seminal prostaglandins by absorption chromatography resulted in a dramatic decrease in immune suppressive activity. Further studies with fractions obtained by ion-exchange HPLC of desalted seminal plasma indicated that prostaglandins complexed with seminal proteins, and these too were immunosuppressive. The possible relevance of these results to sexually transmitted disease is discussed. 相似文献
10.
A case of priapism in a patient receiving home parenteral nutrition is reported. To our knowledge this is the first such case to occur in a patient receiving home parenteral nutrition. The literature is reviewed and the possible aetiology discussed. 相似文献