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51.
52.
Stewart MG Cristol D Philips R Steele RJ Stamatakis A Harrison E Clayton N 《Behavioural brain research》1999,98(1):89-94
In two species of birds, food-storing marsh tits, P. palustris, and non-storing blue tits, P. caeruleus, quantitative receptor autoradiography was used to localize NMDA (N-methyl-D-aspartate)-sensitive [3H]glutamate, [3H]MK801, and [3H]AMPA binding sites, in six regions of the forebrain: hippocampus and parahippocampus, hyperstriatum accessorium (vision) and ventrale (sensory integration), neostriatum (auditory), and lobus parolfactorius (basal ganglia). In both species high levels of labelling to both NMDA and AMPA receptors were observed throughout the forebrain. However, a marked difference in receptor labelling was apparent between the two species, with levels of binding to NMDA ion channel sites being significantly lower (20%) in both the hippocampus and parahippocampus, in food storers compared to non-food storers. The levels of binding to other forebrain regions were remarkably similar in the two species. No differences were seen in the binding to AMPA receptors in forebrain regions of either species. 相似文献
53.
State-of-the-art downstream interventions are generally successful for half of drug-abusing clients. But, only one in four abusers actually receives treatment. In the midstream, one setting (schools), one type of prevention ("one size fits all"), and a limited age-range focus (adolescence and preadolescence) have predominated. Accumulating evidence casts doubt on the effectiveness of widely disseminated school-based prevention approaches, although theory-based programs that emphasize skills training and adjunctive parent and neighborhood interventions fare better. Newer pursuits include intervening very early with higher risk children and expanding to primary health care settings and workplaces. Popular but unproven community approaches need more rigorous evaluation. Upstream national and state public policy and environmental interventions should be reexamined in light of their success for preventing tobacco and alcohol use. 相似文献
54.
C R Hicks A B Clayton S Vijayasekaran G J Crawford T V Chirila I J Constable 《Ophthalmic plastic and reconstructive surgery》1999,15(5):326-332
PURPOSE: To develop a poly(2-hydroxyethyl methacrylate) orbital implant that allows tissue ingrowth and direct muscle attachment to minimize the risk of extrusion and to enhance cosmesis. METHODS: Assessment of clinical outcomes and histologic findings after implantation of 18 prototype prostheses into rabbits. The implants were not wrapped with other tissues or materials. RESULTS: One case of infection was observed but there were no extrusions, with up to 21 months follow-up. Biocolonization was confirmed histologically. Good movement was observed when a cosmetic shell was fitted. CONCLUSIONS: The prototype prosthesis appears promising, with particular advantages being the direct attachment of extraocular muscles, good cosmesis and movement, and a low complication rate in this pilot study. 相似文献
55.
Scarfe GB Wright B Clayton E Taylor S Wilson ID Lindon JC Nicholson JK 《Xenobiotica; the fate of foreign compounds in biological systems》1999,29(1):77-91
1. The metabolism and urinary excretion of 2-chloro-4-trifluoromethylaniline has been studied in the rat using 19F-NMR spectroscopy and directly coupled HPLC-NMR-MS methods. The compound was dosed to three male Sprague-Dawley rats (50 mg kg(-1) i.p.) and urine collected over 0-8, 8-24 and 24-48 h post-dosing. 2. A total urinary recovery of 56.3+/-2.2% of the dose was achieved up to 48 h after dosing. The major metabolite in the urine was identified as 2-amino-3-chloro-5-trifluoromethylphenylsulphate accounting for a total of 33.5+/-2.2% of the dose. 3. Further metabolites detected and characterized included 2-chloro-4-trifluoromethylphenylhydroxylamine glucuronide (13.2+/-0.5% of the dose), 2-amino-3-chloro-5-trifluoromethylphenylglucuronide (3.8+/-0.4% of the dose) and 2-chloro-4-trifluoromethylaniline-N-glucuronide (3.6+/-0.1% of the dose). Several minor metabolites were also found and identified, including 2-chloro-4-trifluoromethylphenylsulphamate, which together accounted for 2.1+/-0.4% of the dose. 4. Directly coupled HPLC-NMR-MS and 19F-NMR spectroscopy is shown to provide an efficient approach for the unequivocal and rapid determination of the quantitative urinary metabolic fate and excretion balance of a fluorinated xenobiotic without the necessity for specific radiolabelling. 相似文献
56.
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58.
Functional hallux rigidus in the rheumatoid foot 总被引:1,自引:0,他引:1
Hallux rigidus results from arthritic involvement of the first metatarsophalangeal joint. The authors have observed loss of motion at this joint in patients with rheumatoid arthritis in the absence of hallux valgus or joint destruction. A hyperextension deformity of the interphalangeal joint has also been observed, with a painful callus beneath it. The first metatarsophalangeal joint appears normal on roentgenograms, and passive motion of the joint is normal when it is examined clinically. The loss of first metatarsophalangeal motion is functional, and stems from muscle spasm of the great toe intrinsic muscles in an effort to relieve pressure on the lesser metatarsal heads. The interphalangeal hyperextension may develop secondary to "functional hallux rigidus." 相似文献
59.
60.
L Patel PE Clayton ME Jenney JE Ferguson TJ David 《Archives of disease in childhood》1997,76(6):505-508
Cross sectional studies have reported impaired growth in children with atopic dermatitis. If this growth impairment is irreversible, it would be expected to adversely influence final height attainment. The standing heights and other anthropometric parameters were assessed in 35 adults with onset of atopic dermatitis before 5 years of age and a control group of 35 adults with adult onset contact dermatitis or psoriasis. There was no significant difference in the standing height SD score, mid-parental height SD score, sitting height SD score, subischial leg length SD score, nor body mass index between the atopic dermatitis and control groups. The standing height SD score was not significantly different among: (a) patients with atopic dermatitis affecting less than 50% of their body surface area and those with greater than 50% affected; (b) patients using the four different potency topical corticosteroids; and (c) patients with atopic dermatitis without asthma and those with coexisting asthma. It is concluded that short stature is not a feature of our group of adult patients with onset of atopic dermatitis before 5 years of age, continuing into adulthood, and severe enough to require specialist care. This suggests that if growth impairment occurs in childhood, it is likely to be temporary and reversible. 相似文献