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51.
PURPOSE: To present a case of laryngeal damage in an infant caused by a too large and inappropriately designed cuffed tracheal tube. CLINICAL FEATURES: A 13-month-old child undergoing cardiac surgery was intubated with an uncuffed endotracheal tube with an internal diameter (ID) of 4.0 mm. Because of an important air leak around the tracheal tube during mechanical ventilation, a cuffed endotracheal tube ID 4.0 mm was inserted. The air leak with the tube cuff not inflated was acceptable at 25 cm H2O airway pressure. After extubation on the third postoperative day, the patient showed increasing stridor and respiratory deterioration. Fibreoptic laryngoscopy of the spontaneously breathing patient showed a large intra-laryngeal web. After surgical removal of the web, the child rapidly recovered and was discharged from the hospital on the 12th postoperative day. Inspection of the 4.0 mm (ID) cuffed tracheal tube revealed a cuff positioned inappropriately high and an increase of 0.7 mm in outer tube diameter compared to the 4.0 mm (ID) uncuffed tracheal tube from the same manufacturer. The tube cuff is likely to be situated within the larynx when placed in accordance to insertion depth formulas or radiological criteria, as used for uncuffed tracheal tubes in children. CONCLUSION: The larger than expected tracheal tube with its intra-laryngeal cuff position in a 13-month-old child likely caused mucosal damage and an inflammatory reaction within the larynx resulting in granulation tissue formation and fibrous healing around the tracheal tube.  相似文献   
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We report a case of recurrent inguinal lymphocele formation after inguinal lymphadenectomy treated by lymphographic mapping and selective ligation of the lymphatic vessels. Lymphographic mapping was performed by puncturing a lymphatic vessel at the dorsum of the foot. After isolating the vessels that drained into the lymphocele, they were clipped and divided through a small skin incision. The described technique showed an instant and complete suspension of the lymph secretion with subsequent complete healing. Lymphatic mapping and selective ligation of afferent lymphatic vessels proved to be an effective treatment of a recurrent inguinal lymphocele.  相似文献   
54.
Postal questionnaires are widely used to collect data in health research and epidemiologic studies. One problem related to mail surveys is the availability of an up-to-date and accurate list of people in the population from which to draw the sample for the survey. For the identification of incorrect postal addresses it is important that all incorrectly addressed mails are returned as undeliverable. This study examines the proportion of unreturned postal letters that were sent to incorrect addresses. We sent 339 letters to existing addresses throughout Germany, but used fictional names name of persons. Three hundred and three letters (98.2%) were returned as undeliverable. The return rates only slightly differed by layout of the envelopes, region and deliverer.  相似文献   
55.
We tested the hypothesis that bone mineral density (BMD) and bone mineral content (BMC) in proximal human femur specimens in the upper neck region of interest (ROI) and femoral neck axis length (FNAL) provide a significantly better prediction of femoral bone strength than standard ROIs in vitro. BMD and BMC were measured in 110 proximal femur specimens using a standard dual-energy X-ray absorptiometry (DXA) scanner. The analysis included a new ROI in the upper neck as well as the standard ROIs. FNAL was obtained from the scan images. The specimens' failure-load was measured in a mechanical loading device, simulating a fall on the greater trochanter. For the standard ROIs, correlations between failure-load and BMD ranged from R2 = 0.64 (shaft ROI) to R2 = 0.70, p < 0.001 (femoral neck). Prediction of strength by BMD did not significantly differ from those of BMC (R2 ranging from 0.65 to 0.75, p < 0.001). In the upper neck ROI, for both BMD and BMC correlations with failure-load were higher (R2 = 0.76 and 0.81, respectively; p < 0.001). A lower, yet still significant, correlation was found between FNAL and bone strength (R2 = 0.23, p < 0.001). Normalization of failure-load with respect to FNAL did not significantly increase the correlations with densitometric measures. This study provides in vitro evidence indicating that among the ROIs of the proximal femur the newly defined upper neck ROI provides the best prediction of bone strength. Only a weak association was observed between failure load and FNAL.  相似文献   
56.
57.
The synthesis and properties of segmented ABA triblock and (AB)n multiblock copolymer systems with 6,6′-disubstituted 2,2′-bipyridine (bpy) building blocks B and poly(oxytetramethylene) soft segments A are described. The access to the disubstituted bipyridines in large scale quantities was achieved by modification of conventional synthetic routes. In the presence of copper(I) ions these polymers formed mononuclear [Cu(I)(bpy)2] complexes in solution through self-assembly. The complexed copolymers were microphase separated systems in bulk with nano to mesoscopic superstructures consisting of copper-bpy complex aggregates in a polyether matrix. The thermal, mechanical and elastomer properties of the block copolymers varied with composition.  相似文献   
58.
59.
We wanted to clarify whether the postprandial intestinal feedback control activated by nutrients in the distal gut exerts different effects on motility, transit of digesta, and absorption of nutrients in the proximal gut. Additionally, interrelationships among motility, transit, and absorption were to be elucidated because these relationships have only been investigated in the fasted state. In five minipigs, a 150-cm segment of the proximal jejunum was isolated by two cannulas. Motility of the jejunal segment was recorded by multiple strain gauges and analyzed by computerized methods. Markers (Cr- and Cu-EDTA) were used for the measurement of the flow rate, transit time, and absorption of nutrients. After a meal, the test segment was perfused with 2 kcal/min of an elemental diet over a period of 90 min. A feedback inhibition was activated by infusion of nutrients into the midgut at rates of 1–4 kcal/min. Saline was infused as control. With increasing energy loads infused into the midgut, the motility index and the length of contraction waves decreased, whereas the incidence of stationary contractions increased, ie, the motility changed from a propulsive to a segmenting pattern. These modulations of motility were associated with a linear decrease in the flow rate and a linear increase in transit time. Flow and transit were linearly correlated with each other. Additionally, the reduction in flow rate and the delay in luminal transit were associated with a linear increase in the absorption of nutrients. However, the increase in absorption induced by the feedback mechanism was small (7.3–13.4%) compared to the marked inhibition of the motility parameters (54–64%), the flow rate (59%), and the delay of transit (5.8-fold). Feedback control primarily modulated motor patterns and luminal flow, whereas the small increase in absorption was only a side effect due to the longer contact time of the nutrients with the mucosa.The study was supported by the Deutsche Forschungsgemeinschaft, grant Eh 64/6-3.  相似文献   
60.
Two distinct muconate cycloisomerases are involved in the degradation of aniline and 3-chloroaniline (3-CA) proceeding via the ortho-cleavage pathways in Pseudomonas acidovorans CA28. After partial purification of these two enzymes kinetic investigations resulted in a clear differentiation of aniline-derived muconate cycloisomerase (MC) and 3-CA-derived chloromuconate cycloisomerase (CMC). A further result of this study revealed the simultaneous coexistence of MC and CMC in strain CA28 when grown on a mixture of aniline and 3-CA.  相似文献   
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