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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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Cerebral dominance in 56 rats was determined by observing the direction of their turning behavior in response to injection of d-amphetamine (1.5 mg/kg, i.p.). Rats subsequently subjected to kindling of the amygdala developed full epileptic seizures after significantly fewer kindling sessions if the kindling electrodes were in the amygdala of the nondominant, rather than the dominant hemisphere. Kindling rate also showed a significant negative correlation with the total amount of turning after amphetamine. Rats kindled through electrodes in the ventral mesencephalon generally failed to develop full convulsive seizures, and did not show interhemispheric differences in the rate at which they developed preictal behaviors. As the dominant hemisphere of the rat, identified by rotational preference, contains a higher concentration of dopamine, we conclude that even small differences in dopaminergic activity, within the normal physiologic range, can affect the relative susceptibility of the two hemispheres to the development of kindled epilepsy. 相似文献
4.
Endoscopic Reconstruction of Cranial Base Defects following Endonasal Skull Base Surgery. 总被引:3,自引:0,他引:3
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The expanded endonasal approach provides access to the entire ventral skull base for resection of neoplasms involving the skull base and brain. The creation of large defects of the bone and dura endoscopically presents unique reconstructive challenges. A layered reconstruction of the dura with inlay and onlay fascial grafts covered with fat grafts is an effective technique for repair. An intranasal balloon catheter is used to provide counterpressure in the early phase of healing and a lumbar spinal drain is a useful adjunct in patients at increased risk of a cerebrospinal fluid leak. Vascularized flaps may be necessary in some patients receiving radiation therapy. Continued advances in surgical technology and the introduction of new biomaterials will facilitate the reconstruction of skull base defects following endonasal brain surgery. 相似文献
5.
Paul D. Mintz MD President AABB John D. Roback MD PhD Chairman NBF Grants Review Committee 《Transfusion》2005,45(S2):23S-23S
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G Bartzokis H J Garber V J Griswold W H Oldendorf J Mintz S R Marder 《Psychiatry research》1991,40(4):239-245
High resolution magnetic resonance imaging (MRI) of the brain was performed on 18 male schizophrenic patients and 15 male normal control subjects using an identical imaging protocol. The number and size of T2 hyperintense foci were clinically quantified by an academic radiologist. Large foci (greater than or equal to 3 mm in diameter) were observed more frequently on patient images (7/18) than on control images (1/15). The imaging protocol detected high rates of focal hyperintensities, but no differences between patients and controls were noted in the total affected brain area (sum of focal areas) or in the presence or absence of foci. 相似文献
8.
Hausegger KA; Cragg AH; Lammer J; Lafer M; Fluckiger F; Klein GE; Sternthal MH; Pilger E 《Radiology》1994,190(1):199
9.
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
10.
A patient had extensive congenital oral hyperpigmentation of the tongue. The clinical and histologic features set this case apart from any well-delineated disease. Clinically, the congenital onset, the appearance of large black-brownish lesions, the lack of associated systemic abnormalities, and the histologic findings of prominent deposition of melanin in the basal layer support the diagnosis of physiologic melanosis. The macular lesions of the tongue represent discrete depositions of melanin and exemplify soft tissue pigmentation of developmental origin. 相似文献