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211.
212.
Mitchison DA 《American journal of respiratory and critical care medicine》2004,169(3):334-335
213.
Cercueil JP Ferrant E Isambert N Jouve JL Flesch M Krause D Bedenne L Chauffert B 《Gastroentérologie clinique et biologique》2004,28(12):1281-1283
Although chemoembolization is known to be an effective palliative treatment in hepatocellular carcinoma, it has a limited effect in large tumors. We report the case of a patient with a large hepatocellular carcinoma of the left liver who had a significant and sustained clinical response after six sessions of chemoembolization with a pirarubicin/amiodarone/lipiodol emulsion. Pirarubicin is an anthracycline which penetrates faster than doxorubicin into cancer cells. Amiodarone is a multidrug resistance inhibitor. Polysorbate 80, an excipient of injectable amiodarone stabilizes the anthracycline/lipiodol emulsion. The clinical efficacy of this new formulation could be evaluated in a phase II clinical trial. 相似文献
214.
Amlie Chardac Suraj Shankar M. Cristina Marchetti Denis Bartolo 《Proceedings of the National Academy of Sciences of the United States of America》2021,118(10)
In equilibrium, disorder conspires with topological defects to redefine the ordered states of matter in systems as diverse as crystals, superconductors, and liquid crystals. Far from equilibrium, however, the consequences of quenched disorder on active condensed matter remain virtually uncharted. Here, we reveal a state of strongly disordered active matter with no counterparts in equilibrium: a dynamical vortex glass. Combining microfluidic experiments and theory, we show how colloidal flocks collectively cruise through disordered environments without relaxing the topological singularities of their flows. The resulting state is highly dynamical but the flow patterns, shaped by a finite density of frozen vortices, are stationary and exponentially degenerated. Quenched isotropic disorder acts as a random gauge field turning active liquids into dynamical vortex glasses. We argue that this robust mechanism should shape the collective dynamics of a broad class of disordered active matter, from synthetic active nematics to collections of living cells exploring heterogeneous media.From a physicist’s perspective, flocks are ensembles of living or synthetic motile units collectively moving along a common emerging direction (1–4). They realize one of the most robust ordered states of matter observed over five orders of magnitude in scale and in systems as diverse as motility assays, self-propelled colloids, shaken grains, and actual flocks of birds (3, 5–10). The quiet flows of flocks are in stark contrast with the spatiotemporal chaos consistently reported and predicted in active nematic liquid crystals, another abundant form of ordered active matter realized in biological tissues, swimming cells, cellular extracts, and shaken rods (2, 11). Active nematics do not support any form of long-range order (4, 12). Their structure is continuously bent and destroyed by the proliferation and annihilation of singularities in their local orientation: topological defects (11, 13–15). Unlike in active nematics, topological defects in flocking matter are merely transient excitations which annihilate rapidly and allow uniaxial order to extend over system-spanning scales (4).This idyllic view of the ordered phases of active liquids is limited, however, to pure systems. Disorder is known to profoundly alter the stability of topological defects and the corresponding ordered states in equilibrium condensed matter (16–18), but its role in active fluids remains virtually uncharted territory. All previous studies (19–26), including our own early experiments (22), have been limited to weak disorder and smooth perturbations around topologically trivial states. Unlike in equilibrium, no available experiment, simulation, or theory has ever demonstrated or predicted disorder-induced topological excitations in active matter.In this paper we show how isotropic disorder generically challenges the extreme robustness of flocking matter to topological defects. We map the full phase behavior of colloidal flocks navigating through disordered lattice of obstacles and reveal an unanticipated state of active matter: a dynamical vortex glass. In dynamical vortex glasses, millions of self-propelled particles can steadily cruise through disorder, maintaining local orientational order and without relaxing the topological singularities of their flows. The associated flow patterns are exponentially degenerated and shaped by amorphous ensembles of frozen topological defects, yielding a dynamical state akin to the static vortex-glass phase of dirty superconductors and random-gauge magnets (27–29). Building a theory of flock hydrodynamics beyond the spin-wave approximation, we elucidate the emergence and stabilization of topological vortices by quenched disorder. Finally, we discuss the universality of the dynamical vortex glass phase beyond the specifics of polar active matter and colloidal flocks. 相似文献
215.
Patrick A. Sullivan Helga Gonggrijp Michael J. Crowley J. Barry Ferriss Denis J. O'Sullivan 《Acta diabetologica》1981,18(2):139-146
Summary Plasma angiotensin II concentrations were measured in 14 patients in diabetic ketoacidosis and in two patients with hyperosmolar non-ketotic hyperglycemia, before treatment and again when blood glucose control was restored. In the ketoacidosis group plasma angiotensin II before treatment was markedly raised in all patients with otherwise uncomplicated diabetes, but was within the normal range in some patients with long-term complications such as neuropathy, retinopathy and nephropathy. Mean angiotensin II before treatment was significantly higher in otherwise uncomplicated patients than in those with long-term complications. However, plasma angiotensin II decreased with improved control in all. Angiotensin II levels did not correlate with indices of rehydration such as changes in blood urea, packed cell volume and calculated changes in plasma volume. There was, however, a significant negative association between pretreatment angiotensin II and pH. Two patients with hyperosmolar non-ketotic hyperglycemia were more dehydrated but less acidotic. Pre-treatment angiotensin II in each was well below the mean of the ketoacidosis group. These data are further evidence that the renin-angiotensin system may be impaired in diabetics with long-term complications. In addition, they suggest that factors other than fluid depletion are also important in activating the renin-angiotensin system in uncontrolled diabetes. 相似文献
216.
217.
Susana?Hoette Nicolas?Creuzé Sven?Günther David?Montani Laurent?Savale Xavier?Ja?s Florence?Parent Olivier?Sitbon Carlos?Eduardo?Rochitte Gerald?Simonneau Marc?Humbert Rogerio?SouzaEmail author Denis?Chemla 《Lung》2018,196(2):157-164
Background
The right ventricular ejection fraction (RVEF) is a surrogate marker of right ventricular function in pulmonary hypertension (PH), but its measurement is complicated and time consuming. The tricuspid annular plane systolic excursion (TAPSE) measures only the longitudinal component of RV contraction while the right ventricular fractional area change (RVFAC) takes into account both the longitudinal and the transversal components. The aim of our study was to evaluate the relationship between RVEF, RVFAC, and TAPSE according to hemodynamic severity in two groups of patients with PH: pulmonary arterial hypertension (PAH) and chronic thromboembolic pulmonary hypertension (CTEPH).Methods and Results
Fifty-four patients with PAH (n?=?15) and CTEPH (n?=?39) underwent right heart catheterization and cardiac magnetic resonance (CMR). The ventricular volumes and areas, TAPSE, and eccentricity index were measured. The RVFAC was more strongly correlated with the RVEF (r?=?0.81, p?<?0.0001) than the TAPSE (r?=?0.63, p?<?0.0001). RVEF?<?35% was better predicted by the RVFAC than the TAPSE (TAPSE: AUC?=?0.77 and RVFAC: AUC?=?0.91; p?=?0.042). In the group with the worse hemodynamic status, the RVFAC correlated much better with the RVEF than the TAPSE. There were no significant differences in the CMR data analyzed between the groups of PAH and CETPH patients.Conclusions
The RVFAC is a good index to estimate RVEF in PH patients; even better than the TAPSE in patients with more severe hemodynamic profile, possibly for including the transversal component of right ventricular function in its measurement. Furthermore, RVFAC performance was similar in the two PH groups (PAH and CTEPH).218.
Denis B Perrin P Cailleret AF Guth F Ruetsch M Strentz P 《Gastroentérologie clinique et biologique》2003,27(11):992-997
AIM: To determine knowledge, beliefs, self-reported practices and wishes of French general practitioners regarding colorectal cancer screening before the start of an organized screening program. METHODS: A postal survey of the 600 general practitioners of the Haut-Rhin area was made in 2002. RESULTS: Response rate was 62%. Eighty-five% asked routinely their patients about their family history of colorectal cancer. Colorectal cancer screening was routinely proposed by 92% of practitioners to individuals with a family history (86% with colonoscopy) and by 20% to individuals without family history (69% with faecal occult blood test). Seventy-five% did not know French consensus conference guidelines on colorectal cancer screening. Fifty-three% ordered routinely faecal occult blood testing, mostly for the screening of individuals with family history and for the evaluation of symptoms, mainly iron-deficiency anemia and weight loss. Seventy-seven% would explore with colonoscopy subjects with positive faecal occult blood test. Fifty-four% had personally undergone screening. Fifty-six% considered that mass screening could reduce a lot colorectal cancer mortality and most of them agreed with the forthcoming organized colorectal cancer mass screening program. CONCLUSIONS: Screening for colorectal cancer is ordered less often than screening for female cancers. General practitioners are unaware of current guidelines. Beliefs and practices vary considerably and faecal occult blood testing is often inappropriately prescribed. Medical education concerning screening is needed. Colorectal cancer screening guidelines and policy should be clarified in France. 相似文献
219.
Balloon angioplasty and stenting of multiple intralobar pulmonary arterial stenoses in adult patients. 总被引:1,自引:0,他引:1
Abraham Rothman Denis J Levy Mark S Sklansky Paul D Grossfeld William R Auger Gholam H Ajami Cynthia A Behling 《Catheterization and cardiovascular interventions》2003,58(2):252-260
Balloon angioplasty and stent placement for pulmonary arterial stenoses in children are well-established therapies. In contrast, management of isolated peripheral pulmonary arterial stenoses in adults remains relatively unexplored. Four women (ages 18-63 years) with multiple discrete intralobar pulmonary arterial stenoses were treated with balloon angioplasty. Initially, 4-5 stenoses were dilated in each patient. The mean minimum diameter of the stenoses increased from 1.3 to 3.1 mm (P < 0.001), and the mean ratio of right ventricular to aortic systolic pressure decreased from 0.92 to 0.62 (P < 0.05). Each patient had marked symptomatic improvement. However, three patients developed recurrence of symptoms 4-24 months after angioplasty, and two had angiographic evidence of restenosis at previously dilated sites. These restenoses were treated with repeat angioplasty or stent implantation (three stents in each patient). One of these two patients developed near-occlusive restenosis of the stents and had successful bilateral lung transplantation. The other patient had a third catheterization with successful implantation of three additional stents. The third patient with recurrent symptoms died 2 years later, without further intervention. Transcutaneous catheter therapy for multiple intralobar pulmonary arterial stenoses in adults is highly successful acutely, but restenosis is common within several months. For some patients, balloon angioplasty and stent implantation may provide definitive management, while for others these procedures may serve as a bridge to lung transplantation. 相似文献
220.
Masateru Takigawa Jatin Relan Ruairidh Martin Steven Kim Takeshi Kitamura Antonio Frontera Ghassen Cheniti Konstantinos Vlachos Grégoire Massoullié Claire A. Martin Nathaniel Thompson Michael Wolf Felix Bourier Anna Lam Josselin Duchateau Nicolas Klotz Thomas Pambrun Arnaud Denis Pierre Jaïs 《Heart rhythm》2018,15(12):1853-1861