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61.
Increased severity of disease and persistence of symptoms have been recently reported in some patients with simultaneous infection of Borrelia burgdorferi and Babesia microti in the northeastern and northern midwest United States. This study used a murine model to examine whether defined disease conditions such as arthritis and carditis differed in severity in mice infected solely with B. burgdorferi and in mice coinfected with B. microti and B. burgdorferi. C3H.HeJ and BALB/c mice cohorts were coinfected or singly infected and then monitored experimentally for 15 and 30 days after inoculation. Carditis and arthritis was determined by blinded histopathologic evaluation of myocardium and tibiotarsal joints. Cytokine measurements were made on lymph node and spleen supernatants for interferon-gamma, interleukin (IL)-4, IL-10, and IL-13. No differences were observed for C3H.HeJ mice cohorts; however, coinfected BALB/c mice had a significant increase in arthritis severity at day 30. This clinical observation was correlated with a significant reduction in expression of the cytokines IL-10 and IL-13.  相似文献   
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The hidden duplication past of Arabidopsis thaliana   总被引:19,自引:0,他引:19       下载免费PDF全文
Analysis of the genome sequence of Arabidopsis thaliana shows that this genome, like that of many other eukaryotic organisms, has undergone large-scale gene duplications or even duplications of the entire genome. However, the high frequency of gene loss after duplication events reduces colinearity and therefore the chance of finding duplicated regions that, at the extreme, no longer share homologous genes. In this study we show that heavily degenerated block duplications that can no longer be recognized by directly comparing two segments because of differential gene loss, can still be detected through indirect comparison with other segments. When these so-called hidden duplications in Arabidopsis are taken into account, many homologous genomic regions can be found in five to eight copies. This finding strongly implies that Arabidopsis has undergone three, but probably no more, rounds of genome duplications. Therefore, adding such hidden blocks to the duplication landscape of Arabidopsis sheds light on the number of polyploidy events that this model plant genome has undergone in its evolutionary past.  相似文献   
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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   
67.

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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