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991.
Bubbles are an intrinsic problem in microfluidic devices and they can appear during the initial filling of the device or during operation. This report presents a generalizable technique to extract bubbles from microfluidic networks using an adjacent microfluidic negative pressure network over the entire microfluidic channel network design. We implement this technique by superimposing a network of parallel microchannels with a vacuum microfluidic channel and characterize the bubble extraction rates as a function of negative pressure applied. In addition, we generate negative pressure via a converging-diverging (CD) nozzle, which only requires inlet gas pressure to operate. Air bubbles generated during the initial liquid filling of the microfluidic network are removed within seconds and their volume extraction rate is calculated. This miniaturized vacuum source can achieve a vacuum pressure of 7.23 psi which corresponds to a bubble extraction rate of 9.84 pL/s, in the microfluidic channels we characterized. Finally, as proof of concept it is shown that the bubble removal system enables bubble removal on difficult to fill microfluidic channels such as circular or triangular shaped channels. This method can be easily integrated into many microfluidic experimental protocols. 相似文献
992.
993.
Christel Lenz 《Zeitschrift für Psychodrama und Soziometrie》2013,11(1):181-193
Based on theoretical considerations and case reports, possibilities of scenic work with the life line are presented. It is obvious how clients, already in the initial phase of their therapy, are supported in perceiving themselves as “actors on the stages of their lives”. The scenic experiencing of longitudinal and cross sections on the life line enables clients to create a “subjective theory of disease”. Treatment goals become apparent and can be communicated with respect to a treatment planning. When the addiction can be experienced as history and clients can recognize meaningful correlations on their life lines, motivation and at the same time expectation of self-efficacy for the next steps on their paths through life arises. In psychodramatic work with life lines, anamnesis and diagnostics are closely related to the supporting of the experience of identity, appreciation and meaningfulness. 相似文献
994.
995.
996.
A heart under chronic stress undergoes cardiac remodelling, a process that comprises structural and functional changes including
cardiomyocyte hypertrophy, interstitial fibrosis, contractile dysfunction, cell death and ventricular dilatation. Reactive
oxygen species (ROS)-dependent modulation of intracellular signalling is implicated in the development of cardiac remodelling.
Among the different ROS sources that are present in the heart, NADPH oxidases (NOXs) are particularly important in redox signalling.
NOX isoforms are expressed in multiple cell types including cardiomyocytes, fibroblasts, endothelial cells and inflammatory
cells—with the two main isoforms expressed in the heart being NOX2 and NOX4. Recent studies indicate that NOX-dependent signalling
is involved in the development of cardiomyocyte hypertrophy, interstitial fibrosis and post-MI remodelling. NOXs may also
be involved in the genesis of contractile dysfunction and myocyte apoptosis. Here, we review the main effects of NOXs in the
pathogenesis of cardiac remodelling and the redox-sensitive signalling pathways that underlie these effects. The elucidation
of mechanisms involved in NOX-dependent regulation of cardiac remodelling may lead to new therapeutic targets for heart failure. 相似文献
997.
M. Ravi Sekhar B. R. Patil B. Krishnamurthy C. Bhaskar Rao K. Gopalkrishna 《Journal of maxillofacial and oral surgery》2012,11(1):72-77
Aims
The present study was under taken to evaluate the efficacy of various local and regional soft tissue flaps used for reconstruction after excision of various malignant lesions of the mouth and also to evaluate complications with length of hospital stay after the reconstruction. 相似文献998.
999.
1000.
Richard Kitz Ute Martens Egmont Zieseniß Paul Enck Markus A. Rose 《Central European Journal of Medicine》2012,7(3):362-365
Sinusitis is a frequent complication of respiratory tract infections. Probiotics are perceived to be useful in infections,
allergies, and inflammations. Our prospective trial stratified 204 children with recurrent rhinosinusitis by age (2–11 years,
54m:64f; 12–18 years, 39m:47f) and assigned them to standard treatment (antibiotics, anticongestants) or additional 60 days
Symbioflor-1 (SF1; Enterococcus faecalis 1.5–4.5x107 CFU). The number of sinusitis episodes was lower in SF1-treated patients (2.52±0.91) than among controls (3.27±1.36; p=0.01).
Mean duration of the first sinusitis episode was 11.9±8.6 days with SF1, whereas it was 16.1±12.9 days in the younger controls
(p=0.023) and 9.86±5.05 days in the elder controls (n.s.). Duration of subsequent sinusitis episodes was also shorter in SF1
patients (15.2±13.6 days) compared with controls (22.7±14.8 days; p=0.030). No adverse events were observed. Probiotic Enterococcus
faecalis adjuvant to conventional therapy can reduce the number and duration of rhinosinusitis episodes in children and adolescents. 相似文献