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Introduction The timing of moves to alternative care has implications for the effective support of people with intellectual disabilities and their families. Essex et al. (1997 ) proposed three transition profiles: ‘normative’, ‘stress process’ and ‘postponed’. The applicability of these profiles to people with intellectual disabilities and challenging behaviour was tested. Methods Qualitative analysis of interviews with families of 13 males and five females aged between 11 and 35 years, who had left home, was undertaken. Results Few people moved due to ‘normative’ family life cycle changes. The majority left because of family difficulties (‘stress process’). This model was elaborated and three transition routes described: ‘forensic’– involving police contact (actual/potential), ‘family’– reflecting problems in the family and ‘service’– deficits leading to placement out of district. Conclusions This research suggests that people (particularly young men) with intellectual disabilities and challenging behaviour enter statutory care earlier than their counterparts, and people with different levels of intellectual and physical disabilities follow different transition routes.  相似文献   
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There is a significant medical need for tough biodegradable polymer adhesives that can adapt to or recover from various mechanical deformations while remaining strongly attached to the underlying tissue. We approached this problem by using a polymer poly(glycerol-co-sebacate acrylate) and modifying the surface to mimic the nanotopography of gecko feet, which allows attachment to vertical surfaces. Translation of existing gecko-inspired adhesives for medical applications is complex, as multiple parameters must be optimized, including: biocompatibility, biodegradation, strong adhesive tissue bonding, as well as compliance and conformability to tissue surfaces. Ideally these adhesives would also have the ability to deliver drugs or growth factors to promote healing. As a first demonstration, we have created a gecko-inspired tissue adhesive from a biocompatible and biodegradable elastomer combined with a thin tissue-reactive biocompatible surface coating. Tissue adhesion was optimized by varying dimensions of the nanoscale pillars, including the ratio of tip diameter to pitch and the ratio of tip diameter to base diameter. Coating these nanomolded pillars of biodegradable elastomers with a thin layer of oxidized dextran significantly increased the interfacial adhesion strength on porcine intestine tissue in vitro and in the rat abdominal subfascial in vivo environment. This gecko-inspired medical adhesive may have potential applications for sealing wounds and for replacement or augmentation of sutures or staples.  相似文献   
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Background: Conduction velocity (CV) around the tricuspid valve annulus (TVA) during type 1 atrial flutter (AFL) has been shown to be slowest in the tricuspid valve-inferior vena cava (TV-IVC) isthmus, compared to the septal or free wall segments of the TVA. However, fiber orientation in the triangle-of-Koch suggests that the inferior septum and medial TV -IVC isthmus should be the most slowly conducting segments around the TVA. Methods: To test this hypothesis we evaluated CV around the TVA during type 1 atrial flutter in 11 patients, using an electro-anatomical mapping system (Carto). CV was first calculated in 4 segments around the TVA including the TV-IVC isthmus, lateral free wall, superior free wall and septum, and then calculated in 8 segments around the TVA including medial (MI) and lateral isthmus (LI), inferior (IL) and superior lateral (SL) free wall, lateral (LS) and medial superior (MS) free wall, and superior (SS) and inferior septum (IS). Statistical comparison of CV from these multiple segments was made by one-way analysis of variance. Results: Measured in 4 segments around the TVA, mean CV (m/sec) in the TV-IVC isthmus (0.81 ± 0.23) and the septum (0.93 ± 0.18) was significantly slower than CV in the lateral free wall (1.16 ± 0.23) and superior free wall (1.10 ± 0.20), and CV in the TV-IVC isthmus was significantly slower than in the septum (p < 0.05). However, when analyzed in 8 segments, mean CV in the MI (0.56 ± 0.16) and IS (0.59 ± 0.24) was significantly (p < 0.05) slower than in all other segments including the LI (1.06 ± 0.46), IL (1.17 ± 0.40), SL (1.15 ± 0.40), LS (1.04 ± 0.25), MS (1.15 ± 0.28), and SS (1.26 ± 0.36) segments. Conclusions: Consistent with previous reports, CV around the TVA during type 1 AFL was slowest in the TV-IVC isthmus, compared to the septum, superior and lateral free wall regions. However, when the TVA was further subdivided into 8 segments, CV in the MI and IS segments was significantly slower than in all other segments around the TVA. These observations more precisely define the regions of slow conduction in human type 1 AFL, and are consistent with the known anisotropy and slow conduction in the Triangle of Koch.  相似文献   
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INTRODUCTION: Separating nonisthmus-dependent atrial flutter (AFL) from "organized" atrial fibrillation (AF), or isthmus-dependent AFL, may be difficult using ECG characteristics alone. We hypothesized that temporal and spatial phase analysis of ECG atrial waveforms could effectively separate these rhythms by quantifying subtle variations in ECG atrial activation during supraventricular tachycardias (SVT). METHODS AND RESULTS: We studied 52 patients at electrophysiologic study (EPS) who demonstrated isthmus-dependent (n = 15) and nonisthmus-dependent (n = 9) AFL, atrial tachycardia (n = 6), AV nodal reentry (n = 9), orthodromic reciprocating tachycardia (n = 6), and AF (n = 7). Atrial activity was represented as a series of correlations of an atrial template to successive time samples of the arrhythmia ECG. Spatial phase was analyzed as a reproducible relationship of this atrial activity between leads over time; temporal regularity was measured from power spectra. Spatial phase was maintained (coherent) in lead planes V5/aVF (XY), V5/V1 (XZ), and aVF/V1 (YZ) in 15 of 15 cases of isthmus-dependent AFL, but in only 1 of 9 cases of nonisthmus-dependent AFL (P < 0.01; chi2). Temporally, all cases of AFL showed one dominant peak on correlation spectra (magnitude >6 dB), suggesting one activation wavefront, although this was smeared in nonisthmus-dependent cases. In contrast, AF showed inconsistent spatial phase in all planes and broad band spectra, consistent with multiple and/or variable activation paths. All other SVTs showed spatial coherence and one dominant spectral peak. CONCLUSION: Coherence of temporal and spatial phase is a powerful approach to measure the spatial organization of intracardiac activation from the ECG that reveals a spectrum from SVT to isthmus-dependent and nonisthmus-dependent AFL, to AF.  相似文献   
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We show here that ultrasound-stimulated microbubbles can enhance cell death within tumors when combined with radiation. The aim of this study was to investigate how different ultrasound parameters, different microbubble concentrations and different radiation doses interact to enhance cell death. Prostate xenograft tumors (PC-3) in severe combined immunodeficiency mice were subjected to ultrasound treatment at various peak negative pressures (250, 570 and 750 kPa) at a center frequency of 500 kHz, different microbubble concentrations (8, 80 and 1000 μL/kg) and different radiation doses (0, 2 and 8 Gy). Twenty-four hours after treatment, tumors were excised and assessed for cell death. Histologic analyses revealed that increases in radiation dose, microbubble concentration and ultrasound pressure promoted apoptotic cell death and disruption within tumors by as much as 21%, 30% and 43%, respectively. Comparable increases in ceramide, a cell death mediator, were identified using immunohistochemistry. We also show here that even clinically used microbubble concentrations combined with ultrasound can induce significant enhancement of cell death.  相似文献   
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Transurethral Ureterolithotripsy (TUL) is a frequently used procedure in urology departments. Many urologists perform TUL without antibiotic prophylaxis; however the use of chemoprophylaxis before TUL remains a controversial issue in urology. This study was carried out to assess the safety of omitting antibiotic prophylaxis prior to TUL. In a prospective randomized clinical trial from January 2005 to December 2007, 114 patients with ureteral stones were enrolled; Fifty seven had preoperative antibiotic prophylaxis administered before TUL and fifty seven patients underwent TUL without antibiotic prophylaxis. The rate of postoperative infectious complications (fever, positive blood culture, significant bactriuria), the length of hospital stay and overall stone free rate were compared between the two groups. There was no statistically significant difference between two groups in the operation time, length of hospital stay, postoperative bacteriuria, positive urine culture, postoperative fever and overall success rate of TUL. It appears that the incidence of infectious complications does not increase in patients undergoing TUL without antibiotic prophylaxis if they have negative pre-operative urine culture and antiseptic technique have been performed thorough the procedure.  相似文献   
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Purpose

Despite great advances in medical image segmentation, the accurate and automatic segmentation of endoscopic scenes remains a challenging problem. Two important aspects have to be considered in segmenting an endoscopic scene: (1) noise and clutter due to light reflection and smoke from cutting tissue, and (2) structure occlusion (e.g. vessels occluded by fat, or endophytic tumours occluded by healthy kidney tissue).

Methods

In this paper, we propose a variational technique to augment a surgeon’s endoscopic view by segmenting visible as well as occluded structures in the intraoperative endoscopic view. Our method estimates the 3D pose and deformation of anatomical structures segmented from 3D preoperative data in order to align to and segment corresponding structures in 2D intraoperative endoscopic views. Our preoperative to intraoperative alignment is driven by, first, spatio-temporal, signal processing based vessel pulsation cues and, second, machine learning based analysis of colour and textural visual cues. To our knowledge, this is the first work that utilizes vascular pulsation cues for guiding preoperative to intraoperative registration. In addition, we incorporate a tissue-specific (i.e. heterogeneous) physically based deformation model into our framework to cope with the non-rigid deformation of structures that occurs during the intervention.

Results

We validated the utility of our technique on fifteen challenging clinical cases with 45 % improvements in accuracy compared to the state-of-the-art method.

Conclusions

A new technique for localizing both visible and occluded structures in an endoscopic view was proposed and tested. This method leverages both preoperative data, as a source of patient-specific prior knowledge, as well as vasculature pulsation and endoscopic visual cues in order to accurately segment the highly noisy and cluttered environment of an endoscopic video. Our results on in vivo clinical cases of partial nephrectomy illustrate the potential of the proposed framework for augmented reality applications in minimally invasive surgeries.
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