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排序方式: 共有1303条查询结果,搜索用时 15 毫秒
101.
D'Acquisto F Merghani A Lecona E Rosignoli G Raza K Buckley CD Flower RJ Perretti M 《Blood》2007,109(3):1095-1102
Annexin-1 is an anti-inflammatory protein that plays an important homeostatic role in innate immunity; however, its potential actions in the modulation of adaptive immunity have never been explored. Although inactive by itself, addition of annexin-1 to stimulated T cells augmented anti-CD3/CD28-mediated CD25 and CD69 expression and cell proliferation. This effect was paralleled by increased nuclear factor-kappaB (NF-kappaB), nuclear factor of activated T cells (NFATs), and activator protein-1 (AP-1) activation and preceded by a rapid T-cell receptor (TCR)-induced externalization of the annexin-1 receptor. Interestingly, differentiation of naive T cells in the presence of annexin-1 increased skewing in Th1 cells; in the collagen-induced arthritis model, treatment of mice with annexin-1 during the immunization phase exacerbated signs and symptoms at disease onset. Consistent with these findings, blood CD4+ cells from patients with rheumatoid arthritis showed a marked up-regulation of annexin-1 expression. Together these results demonstrate that annexin-1 is a molecular "tuner" of TCR signaling and suggest this protein might represent a new target for the development of drugs directed to pathologies where an unbalanced Th1/Th2 response or an aberrant activation of T cells is the major etiologic factor. 相似文献
102.
Treatment of inflammatory diseases by selective eicosanoid inhibition: a double-edged sword? 总被引:1,自引:0,他引:1
Eicosanoids are generally considered to be potent pro-inflammatory mediators, and their suppression has, therefore, been a desirable therapeutic goal. However, analysis of the literature reveals that inhibition of specific eicosanoids per se is a simplistic approach because it overlooks the fact that net pathophysiological effects of these lipid mediators arise from a complex balance between eicosanoids derived from different pathways, which might exhibit both pro-and anti-inflammatory activities (depending on organs and disease stage), or which might have essential physiological roles. An alternative strategy, discussed in this review, might be to control inflammatory lipid mediators in such a way as to avoid disrupting this intricate inter-eicosanoid balance and its physiological sequelae. 相似文献
103.
104.
The effects of single dose oral hydralazine on blood flow through human lung tumours 总被引:3,自引:0,他引:3
Hydralazine has been shown to reduce tumour blood flow and to potentiate the cytotoxicity of melphalan and bioreductive agents in mice. In order to determine whether such a strategy might have clinical potential, a study was undertaken to investigate the effects of hydralazine on blood flow through human tumours. Twenty-two patients with carcinoma of the bronchus received a single oral dose of hydralazine in the range 25 to 150 mg (0.37-2.86 mg/kg) according to age and acetylator status. Tumour blood flow was assessed by single photon emission computed tomography (SPECT) performed 10 min following intravenous 99Tcm-HMPAO on two occasions 2-8 days apart, the second being performed 60 min after hydralazine administration. In 20 evaluable patients, hydralazine caused a 38% increase in blood flow through the whole tumour (p = 0.007) and a 28% increase in flow through the tumour centre (p = 0.03) with greater increases occurring in patients sustaining greater falls in peripheral resistance. Tumour vascular resistance fell indicating active vasodilation in arterioles supplying tumours. Side-effects due to hydralazine were reported by eight patients. 相似文献
105.
C. Boulanger NA Flavahan ZS Katusic K. Komori AA Vos and PM Vanhoutte MD Director 《Fundamental & clinical pharmacology》1990,4(5):525-538
Experiments were designed to determine the effect of CRL 41034, a buflomedil analogue, on the adrenergic responsiveness of canine veins. Rings of saphenous vein (without endothelium) were suspended for isometric tension recording in modified Krebs-Ringer bicarbonate solution at 37 degrees C. CRL 41034 produced a concentration-dependent inhibition of the contractions evoked by the alpha adrenergic agonists norepinephrine, phenylephrine and UK 14304 which was insensitive to the blockade of neuronal uptake by cocaine. CRL 41034 was more potent in inhibiting the concentration-dependent contractions evoked by UK 14304 than those by phenylephrine and the antagonism it caused against the response to UK 14304 fulfilled the criteria for competitivity. CRL 41034, at 10(-5) M significantly depressed, and at 10(-4) M abolished the contractions induced by electrical stimulation of the adrenergic nerves and those evoked by the indirect sympathomimetic amine tyramine. Strips of canine saphenous vein were superfused after incubation with [3H] norepinephrine. During sympathetic nerve activation, CRL 41304 increased the stimulation-evoked overflow of [3H] norepinephrine and 3-methoxy-4-dihydroxyphenylglycol; in the presence of rauwolscine the compound only increased the stimulation-evoked overflow of 3,4-dihydroxyphenylglycol. These experiments suggest that the major vascular effects of CRL 41034 in canine veins are blockade of alpha 2-adrenoceptors on vascular smooth muscle, and inhibition of prejunctional alpha 2-adrenoceptors on adrenergic nerve endings. 相似文献
106.
107.
Hinsch E; Ponce AA; Hagele W; Hedrich F; Muller-Schlosser F; Schill WB; Hinsch KD 《Human reproduction (Oxford, England)》1997,12(8):1673-1681
Binding of mammalian spermatozoa to the zona pellucida and the induction of
the acrosome reaction are prerequisites for successful oocyte
fertilization. It has been postulated that xenobiotics that are released in
the environment as well as exposure to pharmaceutical medications may be
associated with reproductive problems in men and wildlife. Examining
physiological and non-physiological effects of particular compounds on
sperm functions requires high quality in-vitro test systems. We established
a reliable combined in-vitro test system with bovine gametes and evaluated
if aliquots of pooled post-thaw spermatozoa are suitable for examining
essential sperm functions. Using cryopreserved semen, the PSA-FITC/Hoechst
33258 staining procedure was applicable to evaluate the acrosomal status
and cell viability. In the bovine hemizona assay, hemizona indices revealed
no differences between cryopreserved and fresh semen. Treatment of
post-thaw bovine spermatozoa with progesterone (1 microM or bovine
follicular fluid (20%) induced the acrosome reaction from 12% (untreated
spermatozoa) to 25% (P < 0.001) and to 22% [corrected] (P < 0.01),
respectively. Incubation of both compounds (1 microM progesterone and 20%
follicular fluid) raised the percentage of acrosome-reacted spermatozoa to
30% (P < 0001). Our results demonstrate that cryopreserved semen can be
integrated into an in-vitro screening model for reproductive toxicology
testing. Pooled, cryopreserved bovine spermatozoa will thus permit
reproducible experiments for clinical and basic science purposes and may
also be applicable for the human system.
相似文献
108.
109.
D S Weerasinghe L Strand R Cooke J Flower J D Hutton 《The New Zealand medical journal》1989,102(878):549-551
Three hundred and twenty-four patients presenting to Wellington Women's Hospital with symptoms suspicious of an ectopic pregnancy were first studied by testing serum for HCG using a new simple and sensitive (25 mIU/mL) ICON pregnancy test. One hundred and thirty ICON tests were positive. Subsequent management: (a) Immediate laparoscopy noted 3 intrauterine and 15 ectopic pregnancies. (b) Twenty-five patients discharged on revised clinical grounds without pregnancies. (c) An immediate ultrasound examination of 87 women showed 58 intrauterine pregnancies (including 1 misdiagnosed ectopic pregnancy) and 29 ectopic pregnancies which were later confirmed at laparoscopy. One hundred and ninety-four ICON tests were negative including two false negative results in patients with ectopic pregnancies. To avoid both unnecessary laparoscopy or the discharge of patients with a possible ectopic pregnancy, patients with symptoms and signs suspicious of an ectopic pregnancy and who present to hospital should have a rapid sensitive HCG assay. Then, if the test is positive (sensitivity 96%), an ultrasound examination can assist in determining the likely site of the pregnancy. 相似文献
110.
A comparison of two methods of scatter compensation in single photon emission computed tomography (SPECT) imaging is made on the basis of improvements in quantification. The methods, scatter-window subtraction and constrained deconvolution of an average point source response function (PSRF), are described; the theoretical basis of each method is also briefly assessed. Improvements in relative quantification offered by each method are measured by examining ratios of counts in hot cylinders to counts in a slightly radioactive background. The cylinder/background concentration ratio was varied by a factor of five; the sizes of the cylinders remained constant. Keeping the diameter of the cylinders constant allowed for an assessment of the effect of concentration differences, without the conflicting effect of variation in the size of the hot source. Results showed that while both scatter-window subtraction and constrained deconvolution offer quantification improvements in the final image, the method of prereconstruction deconvolution of a planar PSRF from each planar projection is substantially more successful than either scatter-window subtraction or other methods of implementing the deconvolution procedure. 相似文献