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Mewissen MW; Erickson SJ; Foley WD; Lipchik EO; Olson DL; McCann KM; Schreiber ER 《Radiology》1989,173(1):155-157
Color Doppler flow imaging or compression ultrasound (US) was used to prospectively determine frequency of thrombosis at 54 venous insertion sites (47 in common femoral veins, seven in right internal jugular veins) after percutaneous placement of Greenfield filters for interruption of the inferior vena cava. Fifty-one filters were successfully placed in 51 patients with a dilator set or a balloon angioplasty catheter. Nine focal thrombi were detected in the common femoral vein (19%) and one in the right internal jugular vein (14%). Use of dilators induced eight thrombi (24%), compared with two (10%) from balloon catheters. The left common femoral vein had a high frequency of thrombosis, regardless of dilation technique (five of nine). Of nine patients with acute common femoral vein thrombosis, four became symptomatic within 10 days after the procedure. Patients may remain asymptomatic or have delayed symptoms; thus, US is valuable for determining patients at risk of thrombosis of the common femoral vein. 相似文献
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R. J. Boyle L‐J. Mah A. Chen S. Kivivuori R. M. Robins‐Browne M. L‐K. Tang 《Clinical and experimental allergy》2008,38(12):1882-1890
Background Several clinical trials suggest that probiotics may have a role in the prevention of eczema. The optimal timing and mechanisms underlying this intervention are not clear. In particular it is not known whether such treatment works during pregnancy or whether postnatal exposure is important. Objective We investigated whether the probiotic Lactobacillus rhamnosus strain GG (LGG) influences fetal immune responses when administered to pregnant women, as a possible mechanism for its protective effects against the development of eczema. Methods Peripheral blood mononuclear cell from 11 adults treated with LGG, and cord blood mononuclear cells (CBMCs) from 73 women participating in a randomized controlled trial of LGG treatment were cultured with heat‐killed LGG, ovalbumin (OVA) or without stimulus. Cells were analysed by flow cytometry and real‐time PCR for markers of dendritic cell (DC) phenotype, T cell proliferation and regulation. Cytokine secretion was analysed in culture supernatants by multiplex cytokine assay. Results LGG treatment of adults led to systemic immune responses suggestive of antigen‐specific tolerance including reduced CD4+ T cell proliferation to heat‐killed LGG (30% reduction; P=0.03). LGG treatment of pregnant women did not influence CD4+ T cell proliferation, forkhead box P3 expression, DC phenotype or cytokine secretion in CBMCs cultured with heat‐killed LGG or OVA. Conclusion LGG treatment of pregnant women fails to influence fetal antigen‐specific immune responses. This suggests that modulation of fetal immune responses may not be a major mechanism by which probiotics such as LGG prevent eczema. 相似文献
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Mouly S Mahé I Champion K Bertin C Popper P De Noblet D Bergmann JF 《International journal of clinical practice》2007,61(3):411-415
To evaluate the ability of two graphologists and two practising internists not trained in graphology to differentiate letters written by subjects who have attempted to commit suicide by self-poisoning and healthy volunteers, we performed a maximal blind controlled study vs. healthy volunteers. Forty fully recovered patients who had attempted to commit suicide and 40 healthy volunteers wrote and signed a short letter or story not related to the parasuicide or their mental health status. The evaluators classified the 80 letters as 'suicide' or 'no suicide' in an intention-to-treat analysis. Letters expressing sadness were subsequently excluded for a per-protocol analysis. Correct diagnosis of suicide and of healthy controls was made in, respectively, 32 of 40 and 33 of 40 letters by the graphologists and in 27 of 40 and 34 of 40 letters by the internists. After the exclusion of 12 letters expressing sadness, the sensitivity, specificity, positive predictive value and negative predictive value were, respectively, 73, 88, 81 and 82% for the graphologists and 53, 89, 80 and 71% for the internists. Both classified the letters with significantly more effectiveness than chance (p < 0.001) with no statistically significant difference between the two groups of evaluators. We concluded that graphological analysis is able to differentiate letters written by patients who attempt suicide from those written by healthy controls. This technique shows an acceptable degree of accuracy and could therefore become an additional discharge or decision-making tool in Psychiatry or Internal Medicine. 相似文献
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Assessment of pacemaker chronotropic response: implementation of the Wilkoff mathematical model 总被引:2,自引:0,他引:2
Freedman RA Hopper DL Mah J Hummel J Wilkoff BL 《Pacing and clinical electrophysiology : PACE》2001,24(12):1748-1754
There are few practical guidelines for proper adjustment of rate responsive pacemaker sensor parameters. This study describes the application of the chronotropic assessment exercise protocol (CAEP) and the Wilkoff model of chronotropic response to assess the adjustment of pacemaker sensor parameters. In 31 patients implanted 1 month previously with a dual sensor pacemaker, pacemaker sensor parameters were adjusted to yield a peak sensor rate of 100 beats/min on a simple 6-minute walk (low intensity treadmill exercise [LITE] protocol); the maximum sensor rate was set to the age predicted maximum heart rate (220-age). The rate response behavior of the pacemaker was then assessed using the slope of metabolic-chronotropic relation (MCR) during CAEP exercise. After adjustments based on the LITE protocol, CAEP exercise yielded MCR slopes of 0.92 +/- 0.25 for the entire study group, which compares well with the predicted normal slope of 1. However, 7 of the 31 patients had sensor MCR slopes during CAEP exercise that were 2 SD or more below expected. To test the sensitivity of this approach to suboptimal pacemaker programming or suboptimal exercise, simulations were performed with the maximum sensor rate programmed below age-predicted maximum heart rate or with exercise truncated before maximum exertion; with these conditions, MCR slopes were sharply lower for the entire group. The authors conclude that a simple treadmill walk (LITE) allowed for optimum programming of sensor parameters in most patients, but in a minority the chronotropic behavior was underresponsive. Failure to appropriately adjust pacemaker maximum sensor rate or failure to achieve peak exercise sharply limits the accuracy of this methodology. 相似文献
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