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Trauma und Berufskrankheit - Nach einem Arbeitsunfall erfolgt die ambulante medizinische Versorgung von Patienten durch spezialisierte Durchgangsärzte. Bisher existiert für diesen Sektor...  相似文献   
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PurposeIn children with cerebral palsy (CP), braces are used to counteract progressive joint and muscle contracture and improve function. We examined the effects of positional ankle–foot braces on contracture of the medial gastrocnemius (MG) and gait in children with CP while referencing to typically developing children.MethodsSeventeen independently ambulant children with CP and calf muscle contracture (age 10.4 ± 3.0y) and 17 untreated typically developing peers (age 9.5 ± 2.6y) participated. Children with CP were analysed before and 16 ± 4 weeks after ankle–foot bracing. MG muscle belly length and thickness, tendon and fascicle length, as well as their extensibility were captured by 2D ultrasound and 3D motion capturing during passive, manually applied stretches. In addition, 3D gait analysis was conducted.ResultsPrior to bracing, the MG muscle–tendon unit in children with CP was 22 % less extensible. At matched amounts of muscle–tendon unit stretch, the muscle belly and fascicles in CP were 7 % and 14 % shorter while the tendon was 11 % longer. Spastic fascicles displayed 32 % less extensibility than controls. Brace wear increased passive dorsiflexion primarily with the knees flexed. During gait, children walked faster and foot lift in swing improved. MG muscle belly and tendon length showed little change, but fascicles further shortened (−11 %) and muscle thickness (−8 %) decreased.ConclusionsUse of ankle–foot braces improves function but may lead to a loss of sarcomeres in series, which could explain the shortened fascicles. To potentially induce gastrocnemius muscle growth, braces may also need to extend the knee or complementary training may be necessary to offset the immobilizing effects of braces.  相似文献   
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A high percentage of cyanotic adults (37%) with cyanotic congenital cardiac disease (CCD) presented with depleted iron stores (13 of 52) or latent iron deficiency (6 of 52), even in a CCD center in which cyanotic patient phlebotomy is mostly avoided. In many of these patients, hypochromia and microcytosis was frequent, whereas hyperchromia and macrocytosis were relatively common.Furthermore, 50% of patients presented with hyperhomocysteinemia, possibly related to folate or B vitamin deficiencies, which may increase red blood cell size and color, explaining the lack of microcytosis and hypochromia in many cyanotic patients with iron deficiency.  相似文献   
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Transthoracic Doppler echocardiography (TDE) has been described as a feasible and accurate technique to noninvasively assess coronary flow reserve (CFR) in the left anterior descending artery (LAD). This study was designed to evaluate whether serial assessment of CFR in the LAD using TDE allows detection of restenosis after previously performed angioplasty. Thirty-three consecutive patients with single-vessel coronary artery disease of the LAD scheduled for angioplasty underwent assessment of coronary flow velocity at rest and during adenosine-induced hyperemia in the distal LAD using high-frequency TDE. CFR was calculated as the ratio of hyperemic to basal systolic/diastolic mean velocity. Investigations were performed before and immediately after angioplasty, and at the time of control angiography after 3 months. CFR results by TDE were compared with intracoronary Doppler guide wire measurements. Adequate pulse-wave Doppler signals to measure CFR were obtained in 30 patients (91%) using TDE. There was close correlation between echocardiographically and intracoronary derived CFR results (r = 0.80, 0.79, and 0.87 before angioplasty, early after, and at 3- month control angiography, respectively; p <0.001). Using a cut-off value of CFR < or =2.0 to identify significant coronary artery disease, TDE detected LAD restenosis with a sensitivity of 89% and specificity of 90%. Thus, high-frequency TDE is a feasible technique to noninvasively assess CFR in the LAD with results closely corresponding to invasive measurements. Defining a cut-off value of CFR < or =2.0, the technique has the potential to reliably detect LAD stenosis after coronary intervention.  相似文献   
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Other persons' laughter, normally perceived as a signal that persons are friendly and inviting others to approach, can also be perceived as a cue of social rejection. In this study, prerecorded laughter was placed in a realistic and personally relevant context, and participants' responses were related to gelotophobia, a trait predisposing to perceiving laughter as a cue of social rejection. Individuals with gelotophobia showed marked heart rate deceleration in response to the laughter stimulus, possibly indicating a “freezing‐like” response. Moreover, cardiac responses to anger provocation by overtly insulting statements indicated heightened aggressive anger in response to cumulated social threat. The study adds to recent research showing specific cardiac responses to social rejection and to the literature on social rejection sensitivity by demonstrating the value of using well interpretable physiological measures in this research context.  相似文献   
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The adverse immune responses to implantable biomedical devices is a general problem with important consequences for the functionality of implants. Immunomodulatory soft hydrogel-based interfaces between the implant and the host can attenuate these reactions. Moreover, encapsulation of the patient''s own immune cells into these interfaces can lead to the personalisation of implants from the immune reaction point of view. Herein, we described a co-crosslinkable composite hydrogel (composed of gelatin and hyaluronic acid), which could be used for the encapsulation of macrophages in the presence of an anti-inflammatory phenotype-fixing cytokine cocktail. To mimick the incoming immune cells on the coating surface in vivo, peripheral blood mononuclear cells were seeded on the hydrogels. The encapsulation of monocytic cells into the composite hydrogels in the presence of cytokine cocktails at 5× or 10× concentrations led to the spreading of the encapsulated cells instead of the formation of clusters. Moreover, the secretion of the anti-inflammatory cytokines IL-1RA and CCL-18 was significantly increased. The attachment of PBMC to the surface of the hydrogel is dependent on the hydrogel composition and also significantly increased in the presence of the cytokine cocktail together with the number of CD68+ cells on the hydrogel surface. Our study demonstrates that the delivery of a polarisation cocktail with biocompatible hydrogels can control the initial response by the incoming immune cells. This effect can be improved by the encapsulation of autologous monocytes that are also polarised by the cytokine cocktail and secrete additional anti-inflammatory cytokines. This interface can fine tune the initial immune response to an implanted biomaterial in a personalised manner.

Hydrogels made from the derivatives of gelatin and hyaluronic acid were used as coatings to control the immune responses.  相似文献   
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