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排序方式: 共有3217条查询结果,搜索用时 15 毫秒
41.
K K Midha E M Hawes J W Hubbard E D Korchinski G McKay 《Journal of clinical psychopharmacology》1989,9(1):4-8
Interpatient variation in response to therapy with antipsychotic drugs is a major problem. This study was designed to assess the extent of variation in disease-free subjects in whom known sources of variance were controlled as much as possible. The subjects were 32 healthy, nonsmoking males of European origin, aged 18-25 years, and weighing no more than +/- 15% from the ideal weight for height. After an overnight fast, each subject ingested 50 mg of chlorpromazine. Plasma samples were harvested over a 24-hour period during which the subjects were on a standardized, caffeine-free diet. Plasma levels of chlorpromazine were measured by gas-liquid chromatography-mass spectrometry. The results showed wide intersubject variation in all pharmacokinetic parameters including maximum concentration, area under the curve, and oral clearance. Furthermore, none of the data were normally distributed. For each pharmacokinetic parameter, the distribution was leptokurtotic and skewed. As a consequence, the geometric means provided better estimates of central tendency than the arithmetic means. It seems that a major proportion of intersubject variation is an inherent problem that cannot be accounted for by differences in race, diet, smoking habits, or concomitant drug ingestion. 相似文献
42.
43.
Summary— Experiments were designed to determine whether or not indapamide, an antihypertensive agent with vasodilator properties, inhibits endothelium-dependent contractions. Rings of aortae with and without endothelium from spontaneously hypertensive rats (SHR) were suspended in conventional organ chambers for the measurement of isometric force. Acetylcholine and adenosine diphosphate-β-S in the presence of a nitric oxide synthase inhibitor, caused endothelium-dependent contractions, which were inhibited by indapamide. The compound (10−4 M) also slightly reduced the contractions of rings without endothelium evoked by U-46,619, which activates thromboxane-endoperoxide receptors. These results demonstrate that indapamide inhibits endothelium-dependent contractions in the SHR aorta, and suggest that the inhibition is due, at least in part, to the action of the drug on the hypertensive vascular smooth muscle. 相似文献
44.
The effect of temperature change upon transmitter release, facilitation and post-tetanic potentiation 总被引:9,自引:3,他引:9
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1. End-plate potentials (e.p.p.s) and miniature end-plate potentials (m.e.p.p.s) were intracellularly recorded from rat diaphragm phrenic nerve preparations in vitro at temperatures between 7 degrees and 40 degrees C.2. The quantal content of e.p.p.s and the frequency of m.e.p.p.s showed broadly similar relationships with temperature, with maxima about 20 degrees and above 39 degrees C.3. Analysis of the change in e.p.p. quantal content showed that the maximum about 20 degrees C was accompanied by a similar maximum of p, the probability of release of quanta. The maximum above 39 degrees C was associated with a rise in n, a presynaptic store of material needed for release.4. The rate at which transmitter could be mobilized was linear in an Arrhenius plot with an apparent activation energy of 25 kcal deg(-1).5. Facilitation and post-tetanic potentiation (PTP) were shown to be entirely attributable to changes in p.6. It is suggested that facilitation and PTP have a common basis and that the (temperature-dependent) rate of Ca removal from intracellular sites at which it exerts its action is as important a determinant of the magnitude of quantal release as is the amount of Ca combining with these sites. 相似文献
45.
A comparison of Skirrow's, Butzler's, Blaser's, Campy-BAP and Preston media for Campylobacter spp was made using human, animal and environmental specimens. Butzler's medium gave the lowest isolation rate and Preston medium, which was the most selective, the highest isolation rate. Enrichment culture using Preston enrichment broth gave a higher isolation rate than direct plating onto Preston medium. 相似文献
46.
Peritoneal fluid concentrations of interleukin-8 in women with endometriosis: relationship to stage of disease 总被引:7,自引:10,他引:7
Gazvani MR; Christmas S; Quenby S; Kirwan J; Johnson PM; Kingsland CR 《Human reproduction (Oxford, England)》1998,13(7):1957-1961
There is increasing evidence that immunological mechanisms play a role in
the pathogenesis and pathophysiology of endometriosis. It was therefore of
interest to study interleukin-8 (IL-8), a chemokine, in the peritoneal
fluid and peripheral blood of women undergoing laparoscopic procedures. The
presence and concentrations of IL-8 in relation to endometriosis,
infertility and abdominal pain were evaluated. Samples of peritoneal fluid
(n = 49) and peripheral blood (n = 50) were obtained from 50 consecutive
patients undergoing laparoscopic surgery for various gynaecological
indications (abdominal pain, infertility, sterilization). IL-8 was present
in the peritoneal fluid of most women (87%). The concentration of IL-8 in
the peritoneal fluid was higher in women with endometriosis compared to
women without (P = 0.02). This difference was more pronounced in early
(stage 1) endometriosis (P = 0.001). IL-8 concentrations in the peritoneal
fluid were also higher in women with early endometriosis compared to women
with later stages of the disease (P = 0.003). Peripheral blood
concentrations did not correlate with peritoneal fluid concentrations of
IL-8 and/or the presence of endometriosis. We conclude that IL-8 is an
important factor that may contribute to the pathogenesis of endometriosis
possibly by promoting neovascularization. This information can be a guide
in the development of new therapeutic approaches for the treatment of
endometriosis.
相似文献
47.
Genes for immunodominant protein antigens are highly homologous in Mycobacterium tuberculosis, Mycobacterium africanum, and the vaccine strain Mycobacterium bovis BCG. 总被引:2,自引:7,他引:2
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M C Lu M H Lien R E Becker H C Heine A M Buggs D Lipovsek R Gupta P W Robbins C M Grosskinsky S C Hubbard et al. 《Infection and immunity》1987,55(10):2378-2382
The relatedness of immunodominant protein antigens in Mycobacterium tuberculosis, M. africanum, and M. bovis BCG was investigated by comparing the genes that encode major protein antigens in M. tuberculosis with their counterparts in the other two mycobacteria. Genes encoding homologs of M. tuberculosis major protein antigens were isolated from M. africanum and M. bovis BCG by constructing lambda gt11 recombinant DNA expression libraries and screening them with murine monoclonal antibodies and DNA probes. The antibodies were directed against four major protein antigens of M. tuberculosis with molecular masses of 71, 65, 19, and 14 kilodaltons. The isolated M. africanum and M. bovis BCG DNA clones were mapped with restriction endonucleases, and the maps of the mycobacterial genes were confirmed by Southern analysis of mycobacterial genomic DNA. The restriction maps of DNA containing the four genes in M. tuberculosis, M. africanum, and M. bovis BCG are identical, indicating that the immunodominant proteins that they encode are highly homologous in the three mycobacteria. Thus, the immunity against tuberculosis engendered by M. bovis BCG vaccination could be provided, at least in part, by the immune response to these homologous antigens. 相似文献
48.
Cellular immune response during uncomplicated genital infection with Chlamydia trachomatis in humans. 总被引:6,自引:13,他引:6
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R C Brunham D H Martin C C Kuo S P Wang C E Stevens T Hubbard K K Holmes 《Infection and immunity》1981,34(1):98-104
Extraction of staphylococcal abscesses by the Folch procedure revealed that all of the staphylocidal activity was present in the lipid fraction. Further separation of the lipids indicated that the bactericidal activity resided in the free fatty acid pool. Lipids similarly extracted from mesenteric or epididymal fat tissue, either before of after activation, did not possess comparable activity. Myristic, palmitic, palmitoleic, linoleic, and oleic acids, as well as lysolecithin, also failed to exhibit the properties of the fatty acid fraction obtained from abscess homogenates. These findings suggest the staphylocidal fatty acid is not a common host lipid. 相似文献
49.
On the mechanism by which calcium and magnesium affect the release of transmitter by nerve impulses 总被引:11,自引:6,他引:11
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1. The relationship between the quantal content of end-plate potentials (e.p.p.s) and the bathing [Ca] and [Mg] was determined at neuromuscular junctions in the rat diaphragm in vitro.2. E.p.p.s were recorded intracellularly from preparations exposed to solutions with [Ca] between 0.05 and 10 mM and [Mg] between 0.1 and 12.5 mM. The quantal content of e.p.p.s was increased by raising the [Ca] over this range and decreased by raising the [Mg]. There appeared to be competition of Mg with Ca at three sites in the nerve terminal membrane.3. A kinetic scheme based on competition of Ca and Mg at three sites could quantitatively explain the effects of Ca and Mg upon the quantal content of e.p.p.s and also the effects of these ions upon miniature end-plate potential frequency. 相似文献
50.
T P Roth A K Hubbard A J Gandolfi B R Brown 《Clinical and experimental immunology》1988,72(2):330-336
Multiple halothane exposures in rabbits generate modified liver proteins or antigens that appear to incorporate the metabolic intermediate of halothane, trifluoroacetyl halide (TFA), as identified by specific anti-TFA antibody. These halothane-induced antigens are most prevalent throughout the second to fourth days following a single halothane exposure and are in highest concentration after the second and third exposure. In addition, five consecutive halothane exposures at 2-week intervals caused the sustained expression of these halothane-induced antigens throughout the first 4 days following the last exposure. By the seventh day, however, antigen expression began to decline. Although there is great heterogeneity in the molecular weights of the halothane-induced antigens, the predominant proteins appear to be 85k, 58k, 53k, 37k and 24k. These liver proteins could reflect self proteins altered by trifluoroacetylation by halothane metabolites and may be potential immunogens in the initiation of a halothane-induced immune response. 相似文献