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排序方式: 共有701条查询结果,搜索用时 15 毫秒
1.
Steve Ramcharitar Mark S Patterson Robert J van Geuns Martin van der Ent Georgios Sianos Gijs M J M Welten Ron T van Domburg Patrick W Serruys 《Catheterization and cardiovascular interventions》2007,70(5):662-668
OBJECTIVES: To directly compare the magnetic navigation system (MNS) guidewires with conventional guidewires in branching tortuous phantoms with operators of varying MNS and percutaneous coronary intervention experience. BACKGROUND: Vessel tortuosity, angulation, and side branches remain limiting factors in coronary interventions. The MNS addresses these limitations by precisely directing the tip of a magnetised guidewire in vivo aided by two permanent adjustable external magnets. METHODS: Crossing and fluoroscopy times of six operators were evaluated in five tortuous Perspex(R) phantom vessels in three consecutive attempts. Standard guidewire (SG) usage was unrestricted. Two 2nd generation magnetic guidewires (MG) were used. Failure was noted if the cross was unsuccessful within 5 min. RESULTS: The magnetic navigation was vastly superior to SG techniques with increasingly tortuous phantoms. It dramatically decreased both the crossing and fluoroscopy times with maximal reduction from 201.7 +/- 111 to 36.4 +/- 13 sec, P < 0.001 and 204.7 +/- 24 to 47.2 +/- 19 sec, P < 0.001, respectively. The MNS had a 98.8% procedural success rate compared to 68% with SG techniques. Moreover it considerably limited the amount of wire usage from 5.5 to 1.3. Operators with prior MG experience performed significantly better than those without, except in the simplest phantom where the difference was nonsignificant (33.8 +/- 13 sec vs. 41.7 +/- 17 sec, P = 0.2). CONCLUSION: MNS significantly reduces both the crossing and fluoroscopy times in tortuous coronary phantom models achieving excellent success rates with dramatic reductions in guidewire usage. Operators with prior MNS experience had an advantage over the inexperienced. 相似文献
2.
Gijs A. Kleter Jan J. M. Damen Mark J. Buijs J. M. Ten Cate 《European journal of oral sciences》1997,105(3):278-284
The Maillard reaction between carbohydrate and protein has been proposed as a cause of the browning of carious lesions. The aim of the present investigation was to determine the occurrence of this reaction in bovine dentin collagen in vitro and to establish the effect of the reaction on the proteolytic degradation of bovine dentin collagen in vitro. Slices of demineralized bovine dentin were incubated with 0.2 M glucose or buffer for 10 weeks at 37°C. The formation of initial (furosine) and advanced (pentosidine) products of the Maillard reaction in dentin exposed to glucose was confirmed by HPLC. After reduction with NaBH4 to prevent intermediate Maillard products from further reaction, slices were either degraded with collagenase for fluorescence measurement or incubated with trypsin or pepsin to assess enzymatic degradation. Fluorescence characteristic for the Maillard reaction increased in glucose-exposed slices. Degradation of collagen by pepsin, but not by trypsin, was greatly depressed following glucose pretreatment. This may indicate an altered sensitivity to proteolytic degradation; the Maillard reaction thus has a potential role in caries arrestment. 相似文献
3.
Renske Oegema George McGillivray Richard Leventer Anne‐Gaëlle Le Moing Nadia Bahi‐Buisson Angela Barnicoat Simone Mandelstam David Francis Fiona Francis Grazia M. S. Mancini Sanne Savelberg Gijs van Haaften Kshitij Mankad Maarten H. Lequin 《American journal of medical genetics. Part C, Seminars in medical genetics》2019,181(4):627-637
4.
Arjan C. Lankester Gijs M. W. Van Schijndel Pauline M. L. Rood Arthur J. Verhoeven Ren A. W. Van Lier 《European journal of immunology》1994,24(11):2818-2825
The SH2 domain-containing transforming Shc protein has been implicated in mitogenic signaling via several surface receptors through p21ras. Following tyrosine phosphorylation by either receptor or non-receptor tyrosine kinases, Shc may interact with the adaptor protein Grb2, which is linked to Sos1, a guanine nucleotide exchange factor for human ras. Ligation of the antigen receptor complex on B cells (BCR) is known to activate various intracellular signaling pathways, which may accumulate in mitogenic responses. With respect to the initial steps, the activation of BCR-associated non-receptor tyrosine kinases appears to be indispensible. In this report we show that Shc proteins become tyrosine phosphorylated after BCR ligation on both transformed and normal human B cells. This is accompanied by the association of Shc with Grb2 proteins and a yet unidentified 145-kDa tyrosine phosphorylated protein. Subcellular fractionation revealed that this activation-induced multimeric Shc complex rapidly translocates towards the plasma membrane. Co-ligation of the BCR with the CD19 molecule results in a marked increase of these events, whereas CD19 cross-linking alone does not induce Shc tyrosine phosphorylation or translocation. Thus, in B cells the Shc complex may represent a molecular junction between the BCR and the mitogenic p21ras cascade. 相似文献
5.
van Noesel Carel J. M.; Lankester Arjan C.; van Schijndel Gijs M. W.; van Lier Rene A. W. 《International immunology》1993,5(7):699-705
The complement receptor 2 (CR2 or CD21) can be found in non-covalentassociation with the Blymphocyte specific CD19 complex at thesurface of mature human B cells. Upon ligation of the B cellantigen receptor complex (BCR), members of the CR2-CD19 complexmay associate with membrane immunoglobulin (mlg). Moreover,CD19 and CD21 ligands, either murine mAb, C3d fragments or Epstein—Barrvirus, are known to have profound effects on B cell activation.We here show that CD19 is tightly linked to the non-receptorsrc kinase Lyn and that the CD19 glycoprotein itself servesas a substrate for a yet undefined serine/threonine kinase presentwithin the complex. In the process of antigen recognition, mlgand the CR2-CD19 complex may bind different sites of a complement-opsonizedantigenic particle. We hypothesize that in this process, approximationto the BCR allows CD19-associated Lyn kinase to phosphorylatepotential substrates within the antigen—receptor complex,thereby effecting its coupling to the intracellular compartment. 相似文献
6.
Joan Rué-Queralt Hugo Fluhr Sebastien Tourbier Yasser Aleman-Gómez David Pascucci Jérôme Yerly Katharina Glomb Gijs Plomp Patric Hagmann 《Human brain mapping》2024,45(5):e26638
Connectome spectrum electromagnetic tomography (CSET) combines diffusion MRI-derived structural connectivity data with well-established graph signal processing tools to solve the M/EEG inverse problem. Using simulated EEG signals from fMRI responses, and two EEG datasets on visual-evoked potentials, we provide evidence supporting that (i) CSET captures realistic neurophysiological patterns with better accuracy than state-of-the-art methods, (ii) CSET can reconstruct brain responses more accurately and with more robustness to intrinsic noise in the EEG signal. These results demonstrate that CSET offers high spatio-temporal accuracy, enabling neuroscientists to extend their research beyond the current limitations of low sampling frequency in functional MRI and the poor spatial resolution of M/EEG. 相似文献
7.
Rajeesh Kumar Pazhavelikkakath Purushothaman Gijs van Erven Daan S. van Es Lon Rohrbach Augustinus E. Frissen Jacco van Haveren Richard J. A. Gosselink 《RSC advances》2023,13(8):4898
A first systematic approach on the base catalyzed depolymerization (BCD) of five technical lignins derived from various botanical origins (herbaceous, hardwood and softwood) and covering the main three industrial pulping methods (soda, kraft and organosolv) is reported. This study provides a first of its kind in-depth quantification and structural characterization of two main BCD fractions namely lignin oil and lignin residue, describing the influence of the BCD process conditions. Depolymerization is evaluated in terms of lignin conversion, lignin oil yield, phenolic monomer selectivity and the production of lignin residue and char. Lignin oils were extensively characterized by size exclusion chromatography (SEC), GC-MS, GC-FID, 13C-NMR, HSQC NMR and elemental analysis. GC × GC-FID was used to identify and quantify distinct groups of monomeric compounds (methoxy phenols, phenols, dihydroxy-benzenes) in the lignin oil. The lignin oil yields (w/w) ranged from 20–31% with total monomer contents ranging from 48 to 57% w/w. SEC analysis indicated the presence of dimers/oligomers in the lignin oil, which through HSQC NMR analysis were confirmed to contain new, non-native interunit linkages. 13C NMR analyses of the lignin oils suggest the presence of diaryl type linkages (i.e. aryl–aryl, aryl C–O) evidencing deconstruction and recombination of lignin fragments during BCD. Irrespective of the lignin source, a residue, often regarded as ‘unreacted’ residual lignin was the main product of BCD (43 to 70% w/w). Our study highlights that this residue has different structural properties and should not be considered as unreacted lignin, but rather as an alkali soluble condensed aromatic material. HSQC, DEPT-135, 13C, and 31P NMR and SEC analyses confirm that the BCD residues are indeed more condensed, with increased phenolic hydroxyl content and lower molecular weights compared to all feed lignins. Subsequent BCD of solid residual fractions produced only low oil yields (6–9% w/w) with lower phenolic monomer yields (4% w/w) compared to original lignin, confirming the significantly more recalcitrant structure. Our study improves the overall understanding of the BCD process, highlights important feedstock-dependent outcomes and ultimately contributes to the complete valorization of BCD-derived lignin streams.Towards a lignin BCD biorefinery! Overall understanding of the BCD process, feedstock-dependent fractionation results, complete valorization of BCD-derived lignin streams. 相似文献
8.
Gijs I. T. Iordens Esther M. M. Van Lieshout Bernd C. Van Es Niels W. L. Schep Roelf S. Breederveld Peter Patka Dennis Den Hartog 《Strategies in trauma and limb reconstruction (Online)》2013,8(3):141-147
Most recent studies on procedures for stabilizing the glenohumeral joint focus on arthroscopic techniques. A relatively simple open procedure is the modified Putti-Platt procedure. The aim of these retrospective case series was to evaluate the functional outcome, patient satisfaction, and quality of life of patients who underwent this procedure. After a median follow-up time of 4.7 (P25–P75 1.7–6.8) years, fifty-one patients could be enrolled with a mean age of 25 (21–39) years. Five patients (10 %) reported re-dislocations. The median Constant score for the affected side was 84 (P25–P75 75–91). Median loss of motion in abduction, elevation, external rotation, and external rotation in 90° of abduction did not exceed 10° when compared to the healthy shoulder. A median Rowe score of 92 (P25–P75 75–95) was measured. The WOSI score and SF-36 showed excellent quality of life. The VAS proved high patient satisfaction with the outcome; 7.9 (6.8–9.5). We concluded that the modified Putti-Platt procedure leads to excellent outcome scores and only marginal restriction in range of motion combined with a high patient satisfaction. Our data prove that excellent results can be obtained with a relatively simple open procedure. 相似文献
9.
Gijs Elshout Marijke Kool Arthur M Bohnen Bart W Koes Henri?tte A Moll Marjolein Y Berger 《The British journal of general practice》2015,65(638):e578-e584
Background
Fever in children in primary care is commonly caused by benign infections, but often worries parents. Information about the duration of fever and its predictors may help in reassuring parents, leading to diminished consultation of health care.Aim
To determine which signs and symptoms predict a prolonged duration of fever in febrile children in primary care and evaluate whether C-reactive protein (CRP) measurement has an additive predictive value for these symptoms.Design and setting
A prospective cohort study at a GPs’ cooperative (GPC) out-of-hours service.Method
Children (aged 3 months to 6 years) presenting with fever as stated by the parents were included. Exclusion criteria were no communication in Dutch possible, previous enrolment in the study within 2 weeks, referral to the hospital directly after visiting the GPC, or no informed consent. The main outcome measure was prolonged duration of fever (>3 days) after initial contact.Results
Four-hundred and eighty children were analysed, and the overall risk of prolonged duration was 13% (63/480). Multivariate analysis combined model of patient history and physical examination showed that ‘sore throat’ (OR 2.8; 95% CI = 1.30 to 6.01) and ‘lymph nodes palpable’ (OR 1.87; 95% CI = 1.01 to 3.49) are predictive for prolonged duration of fever. The discriminative value of the model was low (AUC 0.64). CRP had no additive value in the prediction of prolonged duration of fever (OR 1.00; 95% CI = 0.99 to 1.01).Conclusion
The derived prediction model indicates that only a few signs and symptoms are related to prolonged duration of fever. CRP has no additional value in this model. Overall, because the discriminative value of the model was low, the duration of fever cannot be accurately predicted. 相似文献10.
Charlotte W Ockeloen Marjolein H Willemsen Sonja de Munnik Bregje WM van Bon Nicole de Leeuw Aad Verrips Sarina G Kant Elizabeth A Jones Han G Brunner Rosa LE van Loon Eric EJ Smeets Mieke M van Haelst Gijs van Haaften Ann Nordgren Helena Malmgren Giedre Grigelioniene Sascha Vermeer Pedro Louro Lina Ramos Thomas JJ Maal Celeste C van Heumen Helger G Yntema Carine EL Carels Tjitske Kleefstra 《European journal of human genetics : EJHG》2015,23(9):1270-1185
Loss-of-function variants in ANKRD11 were identified as the cause of KBG syndrome, an autosomal dominant syndrome with specific dental, neurobehavioural, craniofacial and skeletal anomalies. We present the largest cohort of KBG syndrome cases confirmed by ANKRD11 variants reported so far, consisting of 20 patients from 13 families. Sixteen patients were molecularly diagnosed by Sanger sequencing of ANKRD11, one familial case and three sporadic patients were diagnosed through whole-exome sequencing and one patient was identified through genomewide array analysis. All patients were evaluated by a clinical geneticist. Detailed orofacial phenotyping, including orthodontic evaluation, intra-oral photographs and orthopantomograms, was performed in 10 patients and revealed besides the hallmark feature of macrodontia of central upper incisors, several additional dental anomalies as oligodontia, talon cusps and macrodontia of other teeth. Three-dimensional (3D) stereophotogrammetry was performed in 14 patients and 3D analysis of patients compared with controls showed consistent facial dysmorphisms comprising a bulbous nasal tip, upturned nose with a broad base and a round or triangular face. Many patients exhibited neurobehavioural problems, such as autism spectrum disorder or hyperactivity. One-third of patients presented with (conductive) hearing loss. Congenital heart defects, velopharyngeal insufficiency and hip anomalies were less frequent. On the basis of our observations, we recommend cardiac assessment in children and regular hearing tests in all individuals with a molecular diagnosis of KBG syndrome. As ANKRD11 is a relatively common gene in which sequence variants have been identified in individuals with neurodevelopmental disorders, it seems an important contributor to the aetiology of both sporadic and familial cases. 相似文献