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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.
Alice H.M. Beare PhD ; Stephen M. Krane MD ; Mark W.J. Ferguson DDS PhD 《Wound repair and regeneration》2005,13(1):27-40
Collagen undergoes dramatic reorganization during wound repair. Matrix metalloproteinases degrade and remodel collagen in a tightly controlled process. The collagenase-resistant mouse, Col1a1(tm1Jae), produces type I collagen, which is resistant to degradation by human matrix metalloproteinase 1. These mice grow normally but develop thickened skin with age. We have previously reported that the early wound repair response in homozygous mutant (Col1a1(r/r)) mice is delayed compared to wild type (Col1a1(+/+)). However, the late-stage scar of Col1a1(r/r) wounds was not significantly altered compared to Col1a1(+/+). Here we have investigated the response of heterozygous mice (Col1a1(+/r)) to wounding, not previously reported. Wound reepithelialization was delayed to a similar degree to wounds in the Col1a1(r/r) mice. However, the recovery of impaired wound contraction was faster in Col1a1(+/r) than in Col1a1(r/r) mice, but still slower than in wild-type animals. Analysis of wound protein extracts showed expression of some matrix metalloproteinases was prolonged in both the Col1a1(r/r) and Col1a1(+/r) wounds compared to wild type. We suggest the partial resistance of collagen to collagenase-mediated degradation in the heterozygous animals causes equivalent impairment of keratinocyte migration compared to homozygous collagenase-resistant mice, but that wound contraction during late-stage healing is only partially retarded. 相似文献
3.
4.
Where patients with cancer die in South Australia 总被引:1,自引:0,他引:1
In a sample of 1582 deaths among South Australian patients with cancer (795 deaths in 1981 and 787 deaths in 1985), 67% of deaths occurred in a hospital, 9% of deaths in a hospice, 10% of deaths in a nursing home, and 14% of deaths in a private residence. More patients died in a hospice or nursing home in 1985 than in 1981, and fewer died in a hospital. With increasing age, fewer patients died in a hospital and more in a nursing home. Compared with men, women were less likely to die at a private residence and more likely to die in a nursing home. A greater proportion of men with a living wife died at a private residence than was so among single or widowed men. However, conjugal status was not associated with the place of death of women. Patients who lived in the more affluent metropolitan suburbs tended more to die at a private residence than did those from poorer suburbs or country areas. Patients with haematological malignancies died in major metropolitan public hospitals more frequently than did patients with other tumours. Possible explanations are given for these findings. 相似文献
5.
Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
6.
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
7.
Focal liver lesions: characterization with triphasic spiral CT 总被引:15,自引:1,他引:14
8.
Metabolic adaptation of the chick embryo to chronic hypoxia 总被引:1,自引:0,他引:1
9.
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
10.
The vasa vasorum and angioplasty 总被引:2,自引:0,他引:2
Cragg AH; Einzig S; Rysavy JA; Castaneda-Zuniga WR; Borgwardt B; Amplatz K 《Radiology》1983,148(1):75-80
Interruption of flow in the vasa vasorum may lead to medial necrosis and aneurysm formation. The purpose of this study was to determine whether angioplasty produces significant alterations in the morphology or blood flow of the vasa vasorum of the dilated artery. The morphology of the canine vasa vasorum was studied before and after angioplasty; in a separate experiment vessel wall blood flow (VWBF) in canine carotid arteries was measured after angioplasty to determine whether physiologic regulation of the blood flow was disrupted by arterial dilation. No morphologic changes could be demonstrated in the vasa vasorum of the dilated artery; however, VWBF was increased by 1194 +/- 215% (mean +/- standard error, p less than 0.01) between 90 and 120 minutes after angioplasty. VWBF in the adjacent nondilated arterial segment was also increased (720 +/- 177% between 10-30 minutes, p less than 0.01) but returned toward normal after 60 minutes. Adenosine caused a "paradoxical" decrease in VWBF (p less than 0.05) of the dilated arterial segment while causing increased VWBF (p less than 0.05) in the thoracic aorta. Angioplasty appears to produce persistent hyperemia in the dilated arterial wall. A paradoxical response to adenosine suggests that vasa vasorum in the dilated arterial segment are maximally vasodilated. This may be due to mechanical disruption of vasomotor tone or to release of vasoactive substances. 相似文献