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51.
Keith May 《American journal of obstetrics and gynecology》1991,165(6):2000-2002
52.
R Dixon AM Hughes K Nairn M Sellers JV Kemp RA Yates 《Cephalalgia : an international journal of headache》1998,18(7):468-475
Zolmitriptan (ZomigTM ) is a 5HT1B/1D agonist which has the ability to cross the intact blood-brain barrier to access central as well as peripheral receptors. Because of the potential for central nervous system side effects, this randomized, double-blind, placebo-controlled, 6-period crossover study evaluated the effects of 2.5 and 5 mg doses of zolmitriptan on psychomotor performance and investigated any pharmacodynamic or pharmacokinetic interaction with diazepam. Twelve healthy volunteers received the following "treatments" as single doses: zolmitriptan 2.5 mg, zolmitriptan 5 mg, diazepam 10 mg, zolmitriptan 2.5 mg+diazepam 10 mg, zolmitriptan 5 mg+diazepam 10 mg and placebo. Pre-dose and at 1, 4, 8, and 24 h post-dose, the following validated battery of psychomotor tests was performed: Bond-Lader visual analogue scales (calmness, contentedness, and alertness factors), critical flicker fusion test, choice reaction time (recognition, motor, and total reaction times), finger-tapping test, number cancellation test and digit symbol substitution test. Plasma concentrations of zolmitriptan, its active metabolite, and diazepam and its active metabolites were measured at the same timepoints. Zolmitriptan 2.5 and 5 mg had no effect on psychomotor function when given alone. In contrast, diazepam 10 mg had profound effects, consistent with its sedative properties, but there was no synergism on concomitant administration of either dose of zolmitriptan. Plasma concentrations of zolmitriptan, diazepam, and their respective active metabolites were similar when the two drugs were given alone or in combination. 相似文献
53.
T May 《European journal of pharmacology》1992,215(2-3):313-316
Experiments were carried out with brain tissues of ethanol-experienced (long-term ethanol intake but withdrawn) vs. ethanol-naive animals. The in vitro 3H antagonist binding of [3H]SCH 23390 and of [3H]spiperone to striatal dopamine D1- and D2-like receptors revealed no significant changes in KD and Bmax values. Displacement of the 3H antagonist binding by dopamine indicated high- and low-affinity states, which also showed no significant alteration at the D2-like receptor but a 5-fold increase of dopamine affinity at the high-affinity state of the D1-like receptor of the ethanol-experienced rats. 相似文献
54.
Twenty new cases of Silo filler's disease (SFD) have been collected, documenting the incidence and clinical features of exposure to nitrogen oxides present in freshly filled silos. Cases of SFD were identified using a statewide computerized discharge diagnosis system. Fifteen of these were identified in the index period, allowing us to calculate an approximate annual incidence of 5.0 cases/100,000 silo-associated farm workers/yr in New York State. All cases occurred during harvest periods, with 80% in September and October. Corn silage was the gas source in 18 (90%). All cases involved young white men (mean age, 31.5 yr). The most common presenting feature was dyspnea. All victims entered a silo during the peak danger period, and only one used recommended ventilation techniques. Four cases ended in death (20% mortality). Silo filler's disease, although rare, is a potentially devastating disease involving otherwise young, healthy farm workers. It is readily prevented. 相似文献
55.
P J May H Baker P P Vidal R F Spencer R Baker 《The Journal of comparative neurology》1987,266(2):150-170
Serotoninergic fibers have been reported in both the abducens and facial nuclei of the cat. Furthermore, serotoninergic dorsal raphe and oculomotor internuclear neurons occupy similar locations in the periaqueductal gray overlying the oculomotor and trochlear motor nuclei. To resolve the issue of whether these two populations of neurons overlap, serotoninergic fibers were assayed in the abducens and facial nucleus; then the morphologies and distributions of identified serotoninergic neurons and oculomotor internuclear neurons were determined. Both the abducens and facial nuclei contained varicosities labelled with antibody to serotonin, but a much higher density of immunoreactive fibers was present in the latter, especially in its medial aspect. Distinct synaptic profiles labelled with antibodies to serotonin were observed in both nuclei. In both cases, terminal profiles contained numerous small, predominantly spheroidal, synaptic vesicles as well as a few, large, dense-core vesicles. These profiles made synaptic contacts onto dendritic and, in the facial nucleus, somatic profiles that occasionally displayed asymmetric, postsynaptic, membrane densifications. Following injection of horseradish peroxidase into either the abducens or facial nuclei, double-label immunohistochemical techniques demonstrated that the serotoninergic and oculomotor internuclear neurons form two distinct cell populations. The immunoreactive serotoninergic cells were distributed within the dorsal raphe nucleus, predominantly caudal to the retrogradely labelled oculomotor internuclear neurons. The latter were located in the oculomotor nucleus along its dorsal border and in the adjacent supraoculomotor area. Intracellular injection of horseradish peroxidase revealed that oculomotor internuclear neurons have multipolar somata with up to ten long, tapering dendrites that bifurcate approximately five times. Their dendritic fields were generally contained within the nucleus and adjacent supraoculomotor area. In contrast, putative serotoninergic neurons were often spindle-shaped and exhibited far fewer primary dendrites. Many of these long, narrow, sparsely branched dendrites crossed the midline and extended to the surface of the cerebral aqueduct. In the vicinity of the aqueduct they branched repeatedly to form a dendritic thicket. The axons of the intracellularly stained serotoninergic neurons emerged either from the somata or the end of a process with dendritic morphology, and in some cases they produced axon collaterals within the periaqueductal gray. Thus the oculomotor internuclear and serotoninergic populations differ in both distribution and morphology.(ABSTRACT TRUNCATED AT 400 WORDS) 相似文献
56.
57.
58.
Mutations in the retinal guanylate cyclase (RETGC-1) gene in dominant cone-rod dystrophy 总被引:3,自引:0,他引:3
Kelsell RE; Gregory-Evans K; Payne AM; Perrault I; Kaplan J; Yang RB; Garbers DL; Bird AC; Moore AT; Hunt DM 《Human molecular genetics》1998,7(7):1179-1184
The dominant cone-rod dystrophy gene CORD6 has previously been mapped to
within an 8 cM interval on chromosome 17p12-p13. The retinal- specific
guanylate cyclase gene (RETGC-1), which maps to within this genetic
interval and previously was implicated in Leber's congenital amaurosis, was
screened for mutations within this family and in a panel of small families
and individuals with various cone and cone- rod dystrophy phenotypes. A
missense mutation (E837D) was identified in affected members of the CORD6
family, as well as a second missense mutation (R838C) in three other
families with dominant cone-rod dystrophy. RETGC-1 is only the fourth gene
to be implicated in cone-rod dystrophy and this is the first report of
dominant mutations in this gene.
相似文献
59.
Localization of a gene for otosclerosis to chromosome 15q25-q26 总被引:5,自引:0,他引:5
Tomek MS; Brown MR; Mani SR; Ramesh A; Srisailapathy CR; Coucke P; Zbar RI; Bell AM; McGuirt WT; Fukushima K; Willems PJ; Van Camp G; Smith RJ 《Human molecular genetics》1998,7(2):285-290
Among white adults otosclerosis is the single most common cause of hearing
impairment. Although the genetics of this disease are controversial, the
majority of studies indicate autosomal dominant inheritance with reduced
penetrance. We studied a large multi- generational family in which
otosclerosis has been inherited in an autosomal dominant pattern. Five of16
affected persons have surgically confirmed otosclerosis; the remaining nine
have a conductive hearing loss but have not undergone corrective surgery.
To locate the disease- causing gene we completed genetic linkage analysis
using short tandem repeat polymorphisms (STRPs) distributed over the entire
genome. Multipoint linkage analysis showed that only one genomic region, on
chromosome 15q, generated a lod score >2.0. Additional STRPs were typed
in this area, resulting in a lod score of 3.4. STRPs FES (centromeric) and
D15S657 (telomeric) flank the 14. 5 cM region that contains an otosclerosis
gene.
相似文献
60.
Isolation and characterization of Mycoplasma sphenisci sp. nov. from the choana of an aquarium-reared jackass penguin (Spheniscus demersus) 下载免费PDF全文
Frasca S Weber ES Urquhart H Liao X Gladd M Cecchini K Hudson P May M Gast RJ Gorton TS Geary SJ 《Journal of clinical microbiology》2005,43(6):2976-2979
Strain UCMJ was isolated from the choana of a jackass penguin (Spheniscus demersus) with recurrent mucocaseous choanal discharge. Isolation of this mycoplasma expands the known range of species hosting mycoplasmas. The name Mycoplasma sphenisci sp. nov. is proposed for this new species, for which strain UCMJ is the type strain. 相似文献