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991.
The effects of d-amphetamine over a wide range of doses (0.125–4.0 mg/kg IP) on rat unconditioned behaviour were examined in the presence of food and water (experiment 1), in their absence (experiment 2) and after microinjection (2.0 g in 0.5 l) directly into the striatum (experiment 3). In experiment 1 very low doses (0.125 and 0.25 mg/kg) stimulated the intake of food, but not water, and higher doses produced locomotor hyperactivity, rearing, stereotyped sniffing and anorexia. In experiment 2 all doses, including very low doses (0.125 and 0.25 mg/kg), significantly potentiated locomotor activity. In experiment 3, microinjection into the corpus striatum elicited substantial feeding, but not drinking, locomotor activity or stereotyped behaviour. The results suggest that a single graded facilitative mechanism underlies the effects on food intake and other behavioural effects of amphetamine, as implied by a general hypothesis of amphetamine action proposed in the literature, and that these effects may to a large extent by mediated by forebrain dopamine systems. 相似文献
992.
J. S. de Belleroche P. Winn E. Murzi S. F. Williams L. J. Herberg 《Journal of neural transmission (Vienna, Austria : 1996)》1982,54(3-4):137-143
Summary Behavioural studies were carried out to determine whether central cholinergic mechanisms regulate dopaminergic activity by presynaptic mechanisms as suggested by recentin vitro studies. Bilateral injections of a muscarinic receptor agonist, oxotremorine (4g), into the nucleus accumbens were found to enhance dopamine-induced locomotor activity. In rats deprived of presynaptic terminals by pretreatment with intraaccumbens injections of 6-hydroxydopamine, oxotremorine did not enhance dopamine-induced locomotor activity but on the contrary produced a marked reduction of locomotor activity. Although dopamine induced locomotor activity could occur in 6-hydroxydopamine treated animals, the muscarinic regulation was dependent on the presence of the intact dopamine terminal and hence a presynaptic receptor may be involved. 相似文献
993.
994.
The effect of surgery, postoperative combination chemotherapy and postoperative radiotherapy was evaluated in subcutaneously implanted Wistar/Furth rat Wilms' tumor. Four groups were studied. Group A (controls, no treatment given) had a median survival of 44 days. Group B (surgical excision of the primary tumor on day 14 after implantation) showed a median survival of 77 days, with 40% tumor-free long-term survivors (sacrificed on day 175). Group C (excision followed by chemotherapy consisting of vincristine, actinomycin D and adriamycin) had a median survival of 61 days with 35% tumor-free long-term survivors. Group D received the same postoperative chemotherapy as well as radiotherapy and had 55% tumor-free long-term survivors. This tumor may serve as a treatment model for some human Wilms' tumor cases who do not respond well to current therapies. 相似文献
995.
T lymphocytes in patients with Down's syndrome. 总被引:1,自引:0,他引:1
K Wisniewski J M Cobill C B Wilcox E A Caspary D G Williams H M Wisniewski 《Neuropsychopharmacology》1979,14(3):463-471
Individuals with Down's syndrome (DS) are thought to have abnormalities in their immune system, and a tendency to infection and malignancy. Studies to quantify the number of T lymphocytes in the peripheral blood of 82 unselected institutionalized patients (50 DS, 27 controls matched for sex and age, 2 chronic lymphocytic leukemic, 2 acute leukemic, and 1 Hodgkin's disease) were conducted. The numbers of circulating T cells in DS patients did not differ significantly from the control group, and were in the upper limits of normality. Number of "avid" T cells, however, were significantly higher in the DS than in the control group. The blastogenic response of the T cells to mitogen was significantly depressed. The data did not exclude the existence of qualitative abnormalities. Except for DS patients with congenital heart disease, those older than 15 years were not more prone to upper respiratory infections than other institutionalized mentally retarded patients. 相似文献
996.
997.
998.
999.
C. B. Estep G. N. Menon H. E. Williams A. C. Cole 《Bulletin of environmental contamination and toxicology》1977,17(2):168-174
Several samples of commercial grade honey collected from different parts of Tennessee during the summer of 1973 were analyzed for chlorinated hydrocarbon insecticide (CHI) residues. A Modified Mill's Procedure was used to cleanup the samples prior to gas Chromatographic analysis using electron capture (EC) detection. The presence of CHI residues was confirmed by analysis on three different columns of widely varying polarity. Most of the samples contained CHI residues at 0.01—0.30 parts per billion (ppb) level. Beeswax produced during the same season contained several times higher levels of the residue than the honey samples. Recoveries of CHI residues varied from 81–95 percent by the procedure employed. 相似文献
1000.
T D Williams 《American journal of optometry and physiological optics》1977,54(10):721-726
The ophthalmic literature dealing with diseases of the optic nerve, the optic tracts, and the visual cortex was reviewed for the period November 1975 through November 1976. Twenty-nine papers on topics of interest to optometrists were abstracted. The main areas of interest include: papilledema and optic atrophy (with ophthalmoscopic signs of both optic atrophy and papilledema); giant-cell arteritis; papillitis; interesting malformations of the face, palate, and orbital position that occur in conjunction with microphthalmus, situs inversus, and hypoplasia and aplasia of the optic nerve; the proposed association of myopia with unusual eyebrows; myelinated nerve fibers at the nerve head; pigment anomalies; the continuing discussion of nerve-head blood supply; an unexpected cause for nerve-head neovascularization; the importance of the swinging-flashlight test in the diagnosis of glaucoma; an unusual type of glaucomatous cupping; doubts about the peripapillary "halo" as a sign of glaucoma; new uses for old field tests; and new methods of ocular photography. 相似文献