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91.
Changes in posture of the lower extremities induce changes in skin blood flow, known as veno-arteriolar response (VAR). We investigated the relationship between ankle brachial index (ABI) and VAR in patients (ABI<0.9) with peripheral arterial disease (PAD) and age-matched normal controls (ABI>1). We measured ankle pressure, ABI at rest, and post-exercise ABI. Using laser Doppler flowmetry, skin blood flow was measured with the lower extremity in extended and flexed positions and the fractional change (extended-flexed/extended) in blood flow (VAR) was calculated. With external pressure applied serially to the lower extremity in the extended position using a sphygmomanometer, the pressure (PVAR) at which the VAR was similar to that in the flexed position was recorded. Patients and controls did not differ by age or comorbidity, except higher cigarette smoking in patients (95.8% vs. 4.3%, p=0.001). VAR and PVAR were significantly lower in patients than controls (0.42+/-0.16 vs. 0.65+/-0.11 flux/min, p=0.001 and 29+/-8 vs. 48+/-9 mm Hg, p=0.001, respectively). There was significant correlation between ABI-post and VAR (r=0.6, p=0.01) and between the VAR and PVAR (r=0.8, p=0.001). VAR<0.3 flux/min was 100% sensitive, 80% specific, and area under curve of 0.88, p=0.001 for detecting PAD as defined by ABI<0.9. Similarly, PVAR of 22 mm Hg was 100% sensitive, 85% specific, and area under curve of 0.94, p=0.001 for detecting PAD. Skin blood flow by this method correlates with the presence and severity of an abnormal ABI. This may offer a method of monitoring the effect of therapy and regression of peripheral atherosclerosis.  相似文献   
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Most methods of measurement of gastric emptying rely on the serial estimation of intragastric volume and do not separately account for the volume of fluid which has been added to the meal by gastric secretion, duodenal reflux, or swallowed saliva. The volume emptied is therefore underestimated. A method of measuring gastric emptying using [125I]RIHSA and the Volémetron is presented. The volume of fluid added to the meal is taken into consideration in this method, giving a more accurate reflection of gastric emptying. Using this method in the dog, emptying was found to be linear rather than exponential.Supported by South African Medical Research Council grant M14/71/51.  相似文献   
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Introduction

Fractures of the orbital-maxillo-zygomatic complex are among the most common fractures affecting the facial skeleton. Goal of surgical treatment is the realignment of fracture lines for a complete functional and aesthetic rehabilitation.

Materials and Methods

From January 2008 to January 2011 in the Department of Maxillofacial Surgery of Complesso Integrato Columbus of the Università Cattolica del Sacro Cuore in Rome, 25 patients, affected by comminute fractures of the anterior wall of the maxillary sinus associated with fractures of the orbital-maxillary complex were selected. The synthesis of the larger fracture fragments was performed by plates and screws (1.5 mm) while a biocompatible glue (N-Butyl-2-Cyanoacrylate–Glubran2®) was applied to treat the comminute fractures of the anterior wall of the maxillary sinus.

Results and Conclusion

The aim of our article is to report our experience and a review of the literature on application of–Butyl-2-Cyanoacrylate for treatment of comminute fractures of the anterior wall of the maxillary sinus. According to the results achieved in our study the N-Butyl-2-Cyanoacrylate can be indicated to treat comminuted fractures of the anterior wall of the maxillary sinus which could not easily be treated with internal rigid fixation.  相似文献   
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The aim of this study was to assess the prefrontal cortex (PFC) oxygenation response to a 5-min incremental tilt board balance task (ITBBT) in a semi-immersive virtual reality (VR) environment driven by a depth-sensing camera. It was hypothesized that the PFC would be bilaterally activated in response to the increase of the ITBBT difficulty, given the PFC involvement in the allocation of the attentional resources to maintain postural control. Twenty-two healthy male subjects were asked to use medial–lateral postural sways to maintain their equilibrium on a virtual tilt board (VTB) balancing over a pivot. When the subject was unable to maintain the VTB angle within ±35° the VTB became red (error). An eight-channel fNIRS system was employed for measuring changes in PFC oxygenated-deoxygenated hemoglobin (O2Hb-HHb, respectively). Results revealed that the number of the performed board sways and errors augmented with the increasing of the ITBBT difficulty. A PFC activation was observed with a tendency to plateau for both O2Hb-HHb changes within the last 2 min of the task. A significant main effect of the level of difficulty was found in O2Hb and HHb (p < 0.001). The study has demonstrated that the oxygenation increased over the PFC while the subject was performing an ITBBT in a semi-immersive VR environment. This increase was modulated by the task difficulty, suggesting that the PFC is bilaterally involved in attention-demanding tasks. This task could be considered useful for diagnostic testing and functional neurorehabilitation given its adaptability in elderly and in patients with movement disorders.  相似文献   
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