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排序方式: 共有1720条查询结果,搜索用时 15 毫秒
1.
LI-FERN HSU PIERRE JAÏS MÉLÈZE HOCINI PRASHANTHAN SANDERS MARTIN ROTTER YOSHIHIDE TAKAHASHI CHRISTOPHE SCAVÉE FREDERIC SACHER JACQUES CLÉMENTY MICHEL HAÏSSAGUERRE 《Pacing and clinical electrophysiology : PACE》2005,28(S1):S94-S98
The differentiation of pulmonary vein (PV) electrograms from atrial far-field signals during PV isolation (PVI) for atrial fibrillation (AF) may be difficult. In addition, owing to highly variable PV ostial sizes, current fixed-diameter circular PV mapping catheters may not yield optimal electrograms. We evaluated an expandable, circular 15–25 mm diameter, 20-pole mapping catheter for PV mapping during sustained AF in 25 patients. After selective PV angiography to define the ostial position and size, the catheter was introduced into each PV and withdrawn to the most stable proximal position, with optimal wall contact ensured by progressive loop expansion. At each PV ostium, electrograms recorded at high resolution (HR) were compared with those recorded at a resolution similar to that of a standard 10-pole Lasso catheter. After PVI performed during ongoing AF, the presence of residual far-field potentials (FFP) under both set-ups was compared. We mapped 97 PV, including 4 pairs with common ostia. In the HR recordings, the PV potentials had greater amplitude (0.5 ± 0.1 vs 0.3 ± 0.1 mV, P = 0.001) and fragmentation, whereas left atrial FFP were minimized. After successful isolation of all PV, FFP were observed in 33% of left superior and 28% of left inferior PV on the HR recordings, compared to 66% and 61%, respectively under normal resolution. Catheter stability and optimal wall contact, in combination with HR electrograms can optimize circumferential PV mapping during AF and improve the discrimination of FFP postablation. 相似文献
2.
HA Carpay P Matthijsse M Steinbuch PGH Mulde 《Cephalalgia : an international journal of headache》1997,17(5):591-595
In an open, randomized cross-over study in 124 patients, we compared the efficacy, safety and patient preference of oral and subcutaneous sum triptan in the acute treatment of migraine. Patients were treated for 3 attacks or 3 months and then crossed over. Primary clinical efficacy was defined as a reduction in headache severity on a four-point self-rating scale from severe (3) or moderate (2) to mild (1) or none (0), or mild (1) to none (0). Efficacy was evaluated 2 h after the administration of subcutaneous and 4h after the administration of oral sumatriptan. Subcutaneous sumatriptan was significantly more effective than oral sumatriptan in relieving headache (over all three attacks 78% vs 61% improvement), improving clinical disability (55% vs 41 % improvement) and relieving nausea (69% vs 53%), vomiting (72% vs 32%) and phono- or photophobia (67% vs 49%). Median time to recurrence was shorter after subcutaneous (12.5 h) than after oral sumatriptan (18 h); the number of patients experiencing a recurrence was similar Patients reported more adverse events after subcutaneous sumatriptan (1.32 per attack) than after the oral form (0.85 per attack), but all adverse events were mild to moderate in intensity and of short duration. Patient opinion was more often positive after subcutaneous sumatriptan. These results may be useful in counselling patients to choose between the available marketed formulations of sumatriptan. 相似文献
3.
4.
FRDRIC ANDR ANDR VICHERAT GUY BOUSSARD ANDR AUBRY MICHEL MARRAUD 《Chemical biology & drug design》1997,50(5):372-381
To determine the structural perturbations induced by the CαH→Nα exchange in aza-peptides, we have examined by H NMR and IR spectroscopy various derivatives of the aza-analogues of alanine, aspartic acid and asparagine in different organic solvents with increasing polarity. Their general formulas are: R'-AzXaa-NR2R3, R'-Pro-AzXaa-NR2R3 and R-AzXaa-Pro-NR2R3 (where AzXaa denotes the aza-analogue of the amino acid residue Xaa = Ala, Asp, Asn; R = Boc, Z; R2, R3= H, Me, iPr). The aza-analogue of an amino acid residue appears to be a strong p-turn-inducing motif, and the AzAsn carboxamide side-chain is capable of interacting, as a proton donor, with the preceding peptide carbonyl group. 相似文献
5.
超细β-磷酸三钙/聚-L-乳酸复合材料的制备与骨折内固定器的加工 总被引:3,自引:0,他引:3
目的:制备分散性良好的超细β-磷酸三钙(β-TCP)/聚-L-乳酸(PLLA)复合材料及新型可吸收骨折内固定器。方法:通过研磨方法制备β-TCP超细粒子,用一缩二乙二醇作分散剂研磨β-TCP后,再将β-TCP与PLLA超声混合,制得复合材料,经注塑加工制成可吸收骨钉,并采用扫描电镜等方法进行表征。结果与结论:用一缩二乙二醇作分散剂研磨β-TCP后再经超声混合,可以使β-TCP超细粒子在复合材料中分散均匀,粒子大小仅为300nm左右,β-TCP与PLlA基体之间结合良好。超细β-TCP/PLLA复合材料可加工成可吸收骨钉,弯曲强度达到100MPa左右,完全满足松质骨内固定的要求。 相似文献
6.
LARBI EL-MASDOURI ANDR AUBRY GUY BOUSSARD MICHEL MARRAUD 《Chemical biology & drug design》1992,40(6):482-486
The similar conformations and interaction modes of Ac-DL-Leu-Nme2 and Ac-Δ-Leu-NMe2 molecules in the solid state allow the comparison of their geometrical parameters. The most evident variations are essentially restricted to the α,β-unsaturated side-chain which adopts the Z-disposition. The dimensions of the peptide backbone are much less sensitive to α,β-unsaturation, with a small shortening by 0.04 Å and 0.02 Å of the N-Cα and Cα-C′ bonds, respectively, and an increase by 6° of the N-Cα- C′ bond angle. The ethylenic and amide groups in the Δ-Leu derivative are far from coplanarity, and a significant electronic conjugation of the π-orbital is likely to be rejected. 相似文献
7.
ELISABETH GIAUFRÉ MD BERNARD BRUGUEROLLE MD PhD CÉLINE RASTELLO MD MICHEL COQUET MD ANNE MARIE LOREC PharmD † 《Paediatric anaesthesia》1995,5(2):125-128
A new regimen for postoperative analgesia after thoracic surgery is proposed. Eight children received an interpleural infusion using bupivacaine 0.1% in a regimen from 0.5 ml·kg?1·h?1 up to 1 ml·kg?1·h?1, for 48 h according to the pain scores. The plasma levels after 24 h and 48 h were measured as well as the pleural level and in two patients the free fraction of plasma bupivacaine and the plasma PPX (a metabolite of bupivacaine) and one patient the orosomucoid (main plasma protein involved in bupivacaine protein binding) were also measured pre and postoperatively. The results shows the safety of such a regimen, for two days of postoperative analgesia. 相似文献
8.
MN Tabrizi† C Chams-Davatchi† N Esmaeeli† P Noormohammadpoor† F Safar† H Etemadzadeh† HA Ettehadi‡ F Gorouhi† 《Journal of the European Academy of Dermatology and Venereology》2007,21(1):79-84
BACKGROUND: Pemphigus vulgaris (PV) is a severe blistering disease involving the skin and mucous membranes. The most common causes of death in these patients are adverse effects of drugs, and infection. Skin lesions are one of the important sources of infection. Thus, any local treatment that could reduce healing time of lesions and consequently reduce the total dosage of drugs needed to treat is favourable. OBJECTIVE: To evaluate the efficacy of epidermal growth factor (EGF) in reducing healing time of lesions in patients with pemphigus vulgaris. METHODS: In this randomized, double-blind, within-patient, left/right, controlled trial, 20 hospitalized patients with pathologial and immunohistologial (direct and indirect immunoflourecence) proven pemphigus vulgaris (PV) were chosen. In addition, all patients had at least one appropriate pemphigus lesion on each side of the body that had not healed after 2-week systemic therapy and sterile saline washing. EGF (10 microg/g) in 0.1% silver sulfadiazine cream vs. 0.1% silver sulfadiazine cream alone was applied randomly on one side of the body. RESULTS: Kaplan-Meier survival analysis suggested that median time to heal with application of EGF plus silver sulfadiazine cream was 9 days, in comparison with 15 days for silver sulfadiazine cream alone (log-rank test, P=0.0003). No intervention-related adverse effect was observed during the study. CONCLUSIONS: EGF can significantly reduce healing time of skin lesions in patients with pemphigus vulgaris, at least when this cream base is applied (Cochrane skin group identifier: CSG20). 相似文献
9.
基于薄板样条和形状内容的医学图像非刚性配准方法研究 总被引:2,自引:0,他引:2
目的 针对医学图像非刚性点配准的现状,给出一种基于点特征的非刚性配准方法.方法 利用一种新的相似度测量方法--形状内容来解决两幅图像中点的对应关系,并利用点对应关系来估计非刚性映射函数.结果 利用薄板样条实现了医学图像的快速准确非刚性配准.结论 实验结果表明,上述方法获得了很好的配准效果. 相似文献
10.
PETER T. BUSER M.D. MICHEL ZUBER M.D. PETER RICKENBACHER M.D. PAUL ERNE M.D. HANS-RUDOLF JENZER M.D. DIETER BURCKHARDT M.D. 《Echocardiography (Mount Kisco, N.Y.)》1997,14(6):597-605
To define the prevalence of cardioembolic sources found by transesophageal echocardiography (TEE) in different age groups of patients with and without cryptogenic systemic embolism, TEE risk factors for cardiogenic embolism were identified from 341 consecutive patients referred for TEE. One hundred and thirty-five had cryptogenic cerebral or systemic peripheral embolic events (CEE) and 206 other indications for TEE (CTR). Cardioembolic sources were found in 40% of CEE and in 29% of CTR (P < 0.02). Specifically, left atrial (LA) thrombi (P < 0.0001), atrial septal aneurysm with right-to-left shunt (P < 0.002), and atherosclerotic aortic plaques (P < 0.02) were more frequent. The prevalence of potential cardioembolic sources was significantly higher in patients ≥ 70-years old than in younger patients (P < 0.03), specifically LA thrombi (P < 0.004) and atherosclerotic aortic plaques (P < 0.0001). In patients ≥ 70-years old, potential cardioembolic sources were found in 63% and in 40% in CEE and CTR (P = 0.073), respectively. However, LA thrombi were more frequent in CEE (P < 0.003). Thus, potential cardioembolic sources observed by TEE are found more frequently in patients ≥ 70-years old than in younger patients. LA thrombi were more frequent in CEE than in CTR patients ≥ 70-years old. In patients ≥ 70-years old with CEE who are eligible for an anticoagulant regimen, a search for potential cardioembolic sources by TEE should be considered. 相似文献