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21.
Anna Siniscalchi Irene Badini Clementina Bianchi Lorenzo Beani 《Naunyn-Schmiedeberg's archives of pharmacology》1994,350(1):10-14
The influence exerted by monoamines on acetylcholine release was studied in electrically stimulated slices of guinea pig nucleus basalis magnocellularis (nbM) prelabelled with 3H-choline (3H-Ch).Noradrenaline, 30 M, and clonidine, 1 M, reduced the evoked 3H-Ch efflux by about 50%, but phenylephrine, 100 M. did not; idazoxan, 0.1 M. but not prazosin, 1 M, antagonized these effects. pointing to the involvement of alpha2 receptors. Apomorphine, 1 or 30 M. reduced 3H-Ch efflux from nbM slices as well. The effect was shared by quinpirole, 1 or 10 M, but not by 2,3,4,5-tetrahydro-7,8-dihydroxy-1-phenyl-1H-3-benz-azepine (SKF 38393). 10 M, and was antagonized by sulpiride, 1 M, but not by R-(+)-8-chloro-2,3,4,5-tetra-hydro-3-methyl-5-phenyl-1H-3-benzazepin-7-ol (SCH 23390). 1 M, suggesting the involvement of the D2 receptor subtype.5-hydroxytryptamine (5-HT) 0.3–30 M, and alphamethyl-5-HT, 10 M, significantly increased 3H-Ch efflux from nbM slices; the 5-HT2 antagonist ritanserin, 1 M. prevented this response. 2-methyl-5-HT, 1–30 M, inhibited the evoked 3H-Ch efflux and its effect was prevented by the 5-HT3 antagonist 1H,3,5H-tropan-3-yl-3,5-dichlorobenzoate (MDL 72222). 1 M.These findings indicate that i) catecholamines inhibit nbM neurons through alpha2 and D2 receptors and that ii) a complex serotonergic modulation of cholinergic function exists in the nbM, involving the activation of various receptor subtypes. which can mediate opposite responses.
Correspondence to: A. Siniscalchi at the above address 相似文献
22.
Tovi Lehmann Douglas H Graham Erica R Dahl Lilian M G Bahia-Oliveira S M Gennari J P Dubey 《Infection, genetics and evolution》2004,4(2):107-114
Previous studies of Toxoplasma gondii, based on samples dominated by clinical isolates, have concluded that its population structure is clonal, despite the sexual reproduction that occurs in cats. To determine whether this applies to non-clinical isolates, we compared patterns of linkage disequilibrium (LD) among seven loci in samples of T. gondii from Brazil and the US. LD was detected in both locations, but it was substantially lower in Brazil. The lower LD in Brazil can be explained by a higher rate of sexual reproduction between different genotypes (outcrossing) because of a higher rate of transmission. The extent of LD between pairs of physically unlinked loci varied significantly in each location. Moreover, the magnitude of LD between corresponding locus pairs in Brazil and the US was correlated, despite minimal gene exchange between the continents (mean FST = 0.19). The heterogeneity among locus pairs and the correlation in LD between physically unlinked locus pairs from different continents suggests that locus-specific factors, such as epistatic selection are involved in maintaining LD in T. gondii. Possibly, the unique life cycle of T. gondii with its unpredictable transmission among diverse host species and distinct ecological habitats requires specific combinations of alleles from multiple loci. The usefulness of typing isolates based on physically unlinked loci is questioned not only by the geographic variation in the reproductive population structure, but mainly by the low overall predictability of the genotype of one locus based on the genotype in another (unlinked) locus. This predictability ranged between 23 and 45%, but was close to nil for a considerable fraction of locus pairs. 相似文献
23.
两种不同方法经鼻盲探气管插管的临床观察 总被引:1,自引:0,他引:1
目的探讨两种不同方法经鼻盲探气管插管成功率。方法将25例需经鼻盲探气管内插管麻醉的手术患者随机分成观察组(13例)和对照组(12例)。采用镇静镇痛健忘法经鼻腔插入气管内导管,观察组当导管出鼻后孔达咽部时套囊充气10~15ml,对照组不充气。结果观察组13例盲探插管均成功,占100%;对照组12例,盲探成功5例,占42%;其中试验组一次插管成功11例,占85%,对照组为3例,占25%。两组对比有显著性(P<0.01)。结论咽部套囊充气法,可提高经鼻盲探插管的成功率。 相似文献
24.
Mariola Andrzejewska Lilian Yepez-Mulia Amparo Tapia Roberto Cedillo-Rivera Agnieszka E Laudy Bohdan J Staro?ciak Zygmunt Kazimierczuk 《European journal of pharmaceutical sciences》2004,21(2-3):323-329
The synthesis and some germicidal activities in vitro of two congener series of S-substituted 4,6-dihalogeno-2-mercapto-1H-benzimidazoles are reported. There was no substantial difference between antibacterial activities of corresponding 4,6-dichloro- and 4,6-dibromo-derivatives. The present results confirm lower susceptibility to substituted benzimidazoles of Gram-negative compared to Gram-positive bacteria. Minimum inhibitory concentrations (MICs) of a majority of the novel derivatives ranged between 25 and 100microg/ml for Gram-positive bacteria. The most active compounds (MICs for Gram-positive bacteria: 0.78-50microg/ml) were 4,6-dichloro-2-(4-nitrobenzylthio)-1H-benzimidazole and 4,6-dibromo-2-(4-nitrobenzylthio)-1H-benzimidazole that were 4-32 times more potent than nitrofurantoin against all Gram-positive bacteria utilized but Escherichia faecalis, against which they were, respectively, 2 and 4 times less potent than nitrofurantoin. Among Gram-negative bacteria used, Stenotrophomonas maltophilia and Bordetella bronchiseptica were most sensitive (as evidenced by a number of MICs =100microg/ml), whereas Pseudomonas aeruginosa was most resistant to the new benzimidazole derivatives (all MICs >400microg/ml). All the new compounds were at least several times more active against Giardia intestinalis (IC(50): 0.006-0.053microg/ml), and a half of them were at least several times more active against Trichomonas vaginalis (IC(50): 0.0015-0.182microg/ml) than metronidazole (IC(50): 0.210 and 0.037microg/ml, respectively), the drug of choice in the treatment of G. intestinalis and T. vaginalis infections. 相似文献
25.
Lilian Munk Rösing 《British Journal of Psychotherapy》2013,29(1):98-109
The article puts forward an aesthetic and psychoanalytic analysis of Titian's painting, The Flaying of Marsyas, arguing that the painting is a reflection on the human subject as a being constituted by skin and by a core of non‐humanity. The analysis is partly an answer to Melanie Hart's (2007) article ‘Visualizing the mind: Looking at Titian's Flaying of Marsyas', addressing features of the painting not commented on by Hart, and supplementing Hart's (Kleinian) theoretical frame by involving Didier Anzieu's ‘skin ego’, Slavoj Zizek's concept of the ‘non‐human’, Giorgio Agamben's term of the ‘Muselmann’, and Anton Ehrenzweig's psychoanalytic theory of artistic creation. Whereas Hart is focusing on form and colour, I also turn my attention towards the texture of the painting. 相似文献
26.
Jamal A. Ahmed Edna Moturi Paul Spiegel Marian Schilperoord Wagacha Burton Nailah H. Kassim Abdinoor Mohamed Melvin Ochieng Leonard Nderitu Carlos Navarro-Colorado Heather Burke Susan Cookson Thomas Handzel Lilian W. Waiboci Joel M. Montgomery Eyasu Teshale Nina Marano 《Emerging infectious diseases》2013,19(6):1010-1011
27.
Lilian Minne Tudor Toma Evert de Jonge Ameen Abu-Hanna 《Artificial intelligence in medicine》2013,57(2):111-117
ObjectiveRecently, we devised a method to develop prognostic models incorporating patterns of sequential organ failure to predict the eventual hospital mortality at each day of intensive care unit (ICU) stay. In this study, we investigate using a real world setting how these models perform compared to physicians, who are exposed to additional information than the models.MethodsWe developed prognostic models for days 2–7 of ICU stay by data-driven discovery of patterns of sequential qualitative organ failure (SOFA) scores and embedding the patterns as binary variables in three types of logistic regression models. Type A models include the severity of illness score at admission (SAPS-II) and the SOFA patterns. Type B models add to these covariates the mean, max and delta (increments) of SOFA scores. Type C models include, in addition, the mean, max and delta in expert opinion (i.e. the physicians’ prediction of mortality).ResultsPhysicians had a statistically significantly better discriminative ability compared to the models without subjective information (AUC range over days: 0.78–0.79 vs. 0.71–0.74) and comparable accuracy (Brier score range: 0.15–0.18 vs. 0.16–0.18). However when we combined both sources of predictions, in Type C models, we arrived at a significantly superior discrimination as well as accuracy than the objective and subjective models alone (AUC range: 0.80–0.83; Brier score range: 0.13–0.16).ConclusionThe models and the physicians draw on complementary information that can be best harnessed by combining both prediction sources. Extensive external validation and impact studies are imperative to further investigate the ability of the combined model. 相似文献
28.
29.
Rodrigo Vitório Ellen Lirani-Silva Fabio Augusto Barbieri Vivian Raile Florindo Stella Lilian Teresa Bucken Gobbi 《Gait & posture》2013,37(2):330-334
The purpose of the current study was to investigate the role of visual information on gait control in people with Parkinson's disease as they crossed over obstacles. Twelve healthy individuals, and 12 patients with mild to moderate Parkinson's disease, walked at their preferred speeds along a walkway and stepped over obstacles of varying heights (ankle height or half-knee height), under three visual sampling conditions: dynamic (normal lighting), static (static visual samples, similar to stroboscopic lighting), and voluntary visual sampling. Subjects wore liquid crystal glasses for visual manipulation. In the static visual sampling condition only, the patients with Parkinson's disease made contact with the obstacle more often than did the control subjects. In the successful trials, the patients increased their crossing step width in the static visual sampling condition as compared to the dynamic and voluntary visual sampling conditions; the control group maintained the same step width for all visual sampling conditions. The patients showed lower horizontal mean velocity values during obstacle crossing than did the controls. The patients with Parkinson's disease were more dependent on optic flow information for successful task and postural stability than were the control subjects. Bradykinesia influenced obstacle crossing in the patients with Parkinson's disease. 相似文献
30.