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81.
Four dream reports, collected from each of 16 subjects in an experimental night, were analysed using the criteria of Mandler and Johnson's story grammar. The experimental night was the first of the four nights where subjects had spontaneously given a dream report after each of the four awakenings planned in REM sleep. A multivariate analysis of covariance, taking the order of the nights where the experimental night occurred and the order of reports as factors, the number of stories per report as covariate and the number of statements in the setting, the number of statements in the event structure and number of episodes per story as dependent variables, showed that the greater length and complexity of reports collected in the second half of the night depends on a greater effectiveness of the dream production system rather than on a greater accuracy of recall. This increase concerns the organization of individual stories rather than the number of stories developed in a given time. These findings raise the issue of how dream production is re-triggered during REM sleep. To cast light on this issue, it seems important to establish whether and how the themes of the various stories developed in a given dream experience are interrelated. 相似文献
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83.
ANDRZEJ STANKE M.D. CESARE STORTI M.D. ROBERTO de PONTI M.D. JORGE A. SALERNO-URIARTE M.D. 《Journal of cardiovascular electrophysiology》1994,5(9):777-781
Incessant Tachycardia in WPW Syndrome. Three patients in whom permanent AV reentrant tachycardia became the clinical manifestation of Wolff-Parkinson-White syndrome are described. The substrate for the arrhythmia was created by coexistence of a concealed left-sided accessory pathway and an ipsilateral bundle branch block. Pharmacology therapy in all three patients failed to control the tachycardia, which in two cases led to severe left ventricular failure. After successful radio frequency ablation of the accessory pathway (in two) or A V junction (in one), left ventricular function gradually returned to normal. 相似文献
84.
JASON G. ANDRADE M.D. LAURENT MACLE M.D. PAUL KHAIRY M.D. Ph.D. YAARIV KHAYKIN M.D. ROBERTO MANTOVAN M.D. Ph.D. GIUSEPPE DE MARTINO M.D. JIAN CHEN M.D. CARLOS A. MORILLO M.D. PAUL NOVAK M.D. PETER G. GUERRA M.D. GIRISH NAIR M.D. ESTEBAN G. TORRECILLA M.D. ATUL VERMA M.D. 《Journal of cardiovascular electrophysiology》2012,23(12):1295-1301
Early Recurrence in STAR‐AF. Background: Early recurrences of atrial tachyarrhythmias (ERAT) are common after atrial fibrillation (AF) ablation, and predict late recurrences (LR). We sought to determine the impact of different ablation strategies on ERAT and LR. Methods and Results: The STAR‐AF trial randomized 100 patients with paroxysmal or persistent AF to ablation of complex fractionated electrograms (CFAE) alone, pulmonary vein isolation (PVI) alone, or combined PVI + CFAE. Patients were followed for 12 months. ERAT was defined as any recurrence of AF, atrial tachycardia, or flutter (AT/AFL) >30 seconds during the first 3 months of follow‐up. LR was defined as any recurrence of AF/AT/AFL >30 seconds 3–12 months post. Forty‐nine patients experienced ERAT. The index ablation strategy was the only independent predictor of ERAT on multivariate analysis (HR 2.24 PVI vs PVI + CFAE; and HR 2.65 CFAE vs PVI + CFAE). Fifty‐two patients experienced LR. The presence of ERAT (HR 3.23), the use of antiarrhythmic drug (AAD) in the first 3 months postablation (HR 2.85), and the index ablation strategy were independently associated with LR (HR 3.42 PVI vs PVI + CFAE; HR 4.72 CFAE vs PVI + CFAE). Thirty‐five of 49 (71%) patients with ERAT and 17 (33%) of 51 patients without ERAT had LR (P < 0.0001). Among patients with ERAT, increased left atrium size (HR 1.08), the use of AAD in the first 3 months postablation (HR 2.86) and the index ablation strategy were independently associated with LR (HR 4.77 PVI vs PVI + CFAE; HR 4.45 CFAE vs PVI + CFAE). Conclusion: ERAT is common following AF ablation and is strongly associated with LR. Although CFAE ablation alone results in higher rates of early and LR, the addition of CFAE to PVI results in increased long‐term success without an increase in ERAT. (J Cardiovasc Electrophysiol, Vol. 23, pp. 1295‐1301, December 2012) 相似文献
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86.
GIORGIO FASSINA ROBERTO CONSONNI LUCIA ZETTA GIOVANNI CASSANI 《Chemical biology & drug design》1992,39(6):540-548
Molecular recognition between Big Endothelin (Big ET) and a computer generated peptide hydropathically complementary to Big ET[16-29] sequence has been studied by analytical high performance liquid affinity chromatography (HPLAC), circular dichroism (CD) and nuclear magnetic resonance (NMR) experiments. Specific binding was observed between solid support immobilized complementary peptide and Big ET[1-38], [1-32], and [16-32], but not with Big ET fragments [1-21], [16-21], [22-32], and [22-38], obtained by chymotrypsin proteolytic degradation. Selectivity in the recognition process was clearly demonstrated by the ability of complementary peptide affinity column to purify the Big ET molecule from complex peptide mixtures, even when present in very low concentrations. Similar selectivity was evidenced with the Big ET fragment [16-32], [NH2-HLDIIWVNTPEHIVPYG-COOH] containing the entire hydropathically complementary sequence. Binding was followed by marked spectroscopic changes, as monitored by circular dichroism and one- and two-dimensional nuclear magnetic resonance experiments. The NMR spectra of the complementary peptides 1:1 mixture showed variations in the chemical shifts of proton resonances in several residues, both in the main chain (amide protons) and in the side chains (aliphatic and aromatic protons). These data support the hypothesis of a multilocalized type of interaction between complementary peptides, where many residues along the peptide chains participate in co-operative stabilizing contacts in the forming complex. 相似文献
87.
Activated Pyrolytic Carbon Tip Pacing Leads: An Alternative to Steroid-Eluting Pacing Leads? 总被引:1,自引:0,他引:1
MICHELE MASINI MAURO LAZZARI ROBERTO LORENZONI ANNA MARIA DOMICELLI AGNESE MICHELETTI RENZO DIANDA GIUSEPPE MASINI 《Pacing and clinical electrophysiology : PACE》1996,19(11):1832-1835
Pyrolytic carbon technology is known for its excellent mechanical properties and electrical conductivity; it is particularly biocompatible and does not require high production costs. The Sorin S100/4 lead is a ventricular passive fixation lead with a hemispherical electrode surface area of 4 mm2 ; the stimulating tip is made of a graphite core coated by a thin activated pyrolytic carbon layer. We evaluated the acute and medium-term performance of the unipolar version of this lead in 65 patients. At implantation, pacing threshold (at 0.5 ms) was 0.26 ± 0.08 V; pacing impedance (at 5 V and 0.5 ms) was 537 ± 94 Ω and Ft wave amplitude was 15.0 ± 5.5 mV. No lead related complications (dislodgment, perforation, exit block, etc.) occurred in any patient; one patient presented with a wire fracture after 26 months, due to subclavian crush syndrome. Follow-up procedures were performed at 1 week, and 2-, 10-, 18-, and 30-months postimplant. Since the leads were connected to pacemakers from different manufacturers, either voltage or duration thresholds were measured, In approximately two thirds of the patients, with an output of 2.5 V, a mean duration threshold of 0.16 ± 0.13 ms at 1 week, 0.12 ± 0.08 ms at 2 months, 0.11 ± 0.06 ms at 10 months, 0.09 ± 0.06 ms at 18 months, and 0.07 ± 0.03 ms at 30 months, was measured. In the remaining one-third of the patients, a comparable voltage threshold trend was measured. The mean pacing impedance showed a transient drop at 1 week, and then increased to a plateau of about 600 fl reached after 10 months. No sensing defect occurred in any patient. Our data show good acute and intermediate-term results of the S100/4 lead; the early rise in threshold was remarkably blunted. Activated pyrolytic carbon tip leads might therefore be considered as a possible, inexpensive alternative to steroideluting leads. 相似文献
88.
ROBERTO COSTA M.D. Ph .D. KÁTIA REGINA DA SILVA R.N. Ph .D. ROBERTO RACHED M.D. Ph .D. MARTINO MARTINELLI FILHO M.D. Ph .D. FRANCISCO CÉSAR CARNEVALE M.D. Ph .D. LUIZ FELIPE PINHO MOREIRA M.D. Ph .D. NOEDIR ANTONIO GROPPO STOLF M. Ph .D. 《Pacing and clinical electrophysiology : PACE》2009,32(S1):S247-S251
Background: The incidence of venous lesions following transvenous cardiac device implantation is high. Previous implantation of temporary leads ipsilateral to the permanent devices, and a depressed left ventricular ejection fraction have been associated with an increased risk of venous lesions, though the effects of preventive strategies remain controversial. This randomized trial examined the effects of warfarin in the prevention of these complications in high-risk patients.
Method: Between February 2004 and September 2007, we studied 101 adults who underwent a first cardiac device implantation, and who had a left ventricular ejection fraction ≤0.40, or a temporary pacing system ipsilateral to the permanent implant, or both. After device implantation, the patients were randomly assigned to warfarin to a target international normalized ratio of 2.0–3.5, or to placebo. Clinical and laboratory evaluations were performed regularly up to 6 months postimplant. Venous lesions were detected at 6 months by digital subtraction venography.
Results: Venous obstructions of various degrees were observed in 46 of the 92 patients (50.0%) who underwent venography. The frequency of venous obstructions was 60.4% in the placebo, versus 38.6% in the warfarin group (P = 0.018), corresponding to an absolute risk reduction of 22% (relative risk = 0.63; 95% confidence interval = 0.013–0.42).
Conclusions: Warfarin prophylaxis lowered the frequency of venous lesions after transvenous devices implantation in high-risk patients. 相似文献
Method: Between February 2004 and September 2007, we studied 101 adults who underwent a first cardiac device implantation, and who had a left ventricular ejection fraction ≤0.40, or a temporary pacing system ipsilateral to the permanent implant, or both. After device implantation, the patients were randomly assigned to warfarin to a target international normalized ratio of 2.0–3.5, or to placebo. Clinical and laboratory evaluations were performed regularly up to 6 months postimplant. Venous lesions were detected at 6 months by digital subtraction venography.
Results: Venous obstructions of various degrees were observed in 46 of the 92 patients (50.0%) who underwent venography. The frequency of venous obstructions was 60.4% in the placebo, versus 38.6% in the warfarin group (P = 0.018), corresponding to an absolute risk reduction of 22% (relative risk = 0.63; 95% confidence interval = 0.013–0.42).
Conclusions: Warfarin prophylaxis lowered the frequency of venous lesions after transvenous devices implantation in high-risk patients. 相似文献
89.
ROBERTO KASUO MIYAKE MD PhD HERBERT DAVID ZEMAN PhD FLAVIO HENRIQUE DUARTE MD RODRIGO KIKUCHI MD EDUARDO RAMACCIOTTI MD PhD GUNNAR LOVHOIDEN PhD CARLOS VRANCKEN MSci 《Dermatologic surgery》2006,32(8):1031-1038
BACKGROUND: A new noninvasive vein imaging device initially developed for phlebotomy has been tested for the first time for vein treatment. This unique device captures a near infrared vein image, processes it, and projects it onto the skin using green light. OBJECTIVE: To perform the first clinical tests of the device in phlebology. MATERIALS AND METHODS: A pilot study on 23 subjects with varicose veins and telangiectasias was performed. The VeinViewer prototype (V-V-P; Luminetx Corp., Memphis, TN) was tested in five situations: diagnosing feeder veins with the V-V-P, comparison between the V-V-P and ultrasound, marking varicose veins with or without the device, phlebectomy using the V-V-P, and the use of laser and sclerotherapy guided by the V-V-P. RESULTS: One hundred percent of subjects had feeder veins identified by the V-V-P. The ultrasound machine detected fewer feeder veins than the V-V-P, and the device identified more veins than the naked eye in all subjects. The V-V-P could help in finding feeder veins during phlebectomy and in guiding laser and sclerotherapy treatments. CONCLUSION: The device could identify veins that were invisible to the naked eye and too shallow for ultrasound detection. The V-V-P may help find feeder veins and may also help various types of vein treatments. 相似文献
90.
MARIA ELISA VEGA M.D. LEON WAXTEIN M.D. ROBERTO ARENAS M.D. MA. TERESA HOJYO M.D. LUCIANO DOMINGUEZ-SOTO M.D. 《International journal of dermatology》1992,31(2):90-94
The clinical and histopathologic characteristics of patients with ashy dermatosis (n = 20) and lichen planus pigmentosus (n = 11) were analyzed. We found significant clinical differences between both dermatoses, supporting our opinion that they are two separate conditions. Both dermatoses were histologically similar. 相似文献