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Coronary angiography and Doppler flow measurements are most commonly used to assess the patency of anastomoses in the operating theater. Intravascular ultrasound might be another means of monitoring the surgical procedure during coronary artery bypass. Five sheep underwent off-pump bypass of the left anterior descending coronary artery using the left internal mammary artery. The running suture was evaluated by intraoperative fluoroscopy and a coronary intravascular ultrasound probe inserted into the target artery proximal to the anastomosis. Macroscopic examination of the anastomosis was performed to validate the angiographic and intravascular ultrasound images. The diameter, cross-sectional area, and compliance of each anastomosis were calculated in systole and diastole. All anastomoses were patent without signs of stenosis. In one case, intravascular ultrasound showed an intimal flap, which was confirmed by macroscopic examination. The mean major anastomotic diameter was 4.5 +/- 0.5 mm on angiography and 4.0 +/- 0.5 mm on intravascular ultrasound. From the ultrasound data, the mean cross-sectional anastomotic area was calculated as 6.21 +/- 0.1 mm(2) in systole and 5.49 +/- 0.1 mm(2) in diastole, and these data were used to calculate the cross-sectional anastomosis compliance. Coronary intravascular ultrasound can visualize intima-to-intima apposition and provide reliable calculations of anastomosis compliance.  相似文献   
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OBJECTIVE:

Thoracentesis is one of the bedside procedures most commonly associated with iatrogenic complications, particularly pneumothorax. Various risk factors for complications associated with thoracentesis have recently been identified, including an inexperienced operator; an inadequate or inexperienced support team; the lack of a standardized protocol; and the lack of ultrasound guidance. We sought to determine whether ultrasound-guided thoracentesis can reduce the risk of pneumothorax and improve outcomes (fewer procedures without fluid removal and greater volumes of fluid removed during the procedures). In our comparison of thoracentesis with and without ultrasound guidance, all procedures were performed by a team of expert pulmonologists, using the same standardized protocol in both conditions.

METHODS:

A total of 160 participants were randomly allocated to undergo thoracentesis with or without ultrasound guidance (n = 80 per group). The primary outcome was pneumothorax following thoracentesis. Secondary outcomes included the number of procedures without fluid removal and the volume of fluid drained during the procedure.

RESULTS:

Pneumothorax occurred in 1 of the 80 patients who underwent ultrasound-guided thoracentesis and in 10 of the 80 patients who underwent thoracentesis without ultrasound guidance, the difference being statistically significant (p = 0.009). Fluid was removed in 79 of the 80 procedures performed with ultrasound guidance and in 72 of the 80 procedures performed without it. The mean volume of fluid drained was larger during the former than during the latter (960 ± 500 mL vs. 770 ± 480 mL), the difference being statistically significant (p = 0.03).

CONCLUSIONS:

Ultrasound guidance increases the yield of thoracentesis and reduces the risk of post-procedure pneumothorax. (Chinese Clinical Trial Registry identifier: ChiCTR-TRC-12002174 [http://www.chictr.org/en/])  相似文献   
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Background: This study estimated in 7 Italian cities the prevalence of prenatal exposure to ethanol by determining fatty acid ethyl esters (FAEEs; palmitic, palmitoleic, stearic, oleic, linoleic, linolenic, and arachidonic esters) and ethyl glucuronide (EtG) in neonatal meconium samples. Methods: A total of 607 meconium samples were obtained from neonatal wards of 7 public hospitals: Verona and San Daniele del Friuli in the northeast of the country, Reggio Emilia in the middle east, Florence and Rome in the center, and Naples and Crotone in the southwest of the peninsula. Meconium biomarkers were assessed by a validated methodology using liquid chromatography–tandem mass spectrometry and the results categorized using the accepted cutoff of 2 nmol/g total amount of 7 FAEEs and 2 nmol/g EtG, to differentiate between heavy maternal ethanol use during pregnancy and occasional or no use at all. Results: On the basis of the above‐reported cutoffs, the overall prevalence of newborns prenatally exposed to maternal ethanol was 7.9%: 0% in Verona, 4.0% in San Daniele del Friuli, 4.9% in Naples, 5.0% in Florence, 6.2% in Crotone, up to 10.6% in Reggio Emilia, and 29.4% in Rome. Low maternal education level and younger maternal age were associated with biomarker scores over the cutoff. There was also a significant correlation between the highest percentage of prenatal exposure in the capital and certain maternal sociodemographic characteristics. Conclusions: These results indicate considerable variability in the prevalence of fetal exposure to ethanol in different Italian cities, as determined by the objective measurement of biomarkers in meconium. These data, together with previous ones obtained in Barcelona, Spain, indicate that gestational ethanol exposure is widespread, at least in parts of Europe.  相似文献   
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We used fMRI to explore the extent of the anatomical overlap of three neural systems that the literature on developmental dyslexia associates with reading: the auditory phonological, the visual magnocellular, and the motor/cerebellar systems. Twenty‐eight normal subjects performed four tasks during fMRI scans: word and pseudoword reading, auditory rhyming for letter names, visual motion perception, and a motor sequence learning task. We found that the left occipitotemporal cortex (OTC), which previous studies reported to be dysfunctional in dyslexia, can be fractionated into different functional areas: an anterior and lateral area that was activated by both reading and auditory rhyming tasks; a posterior area that was commonly activated by both the reading and the motion perception task and a medial/intermediate area, including the so‐called Visual Word Form Area, which was specifically activated by the reading task. These results show that the left OTC is an area of segregated convergence of different functional systems. We compared our results with the hypoactivation pattern reported for reading in a previous cross‐cultural PET study on 36 dyslexic subjects from three countries. The region of decreased activation in dyslexia overlapped with regions that are specific for reading and those activated during both the auditory rhyming task and the single word and pseudoword reading task described in the present fMRI study. No overlap was found with the activation patterns for the visual motion perception task or for the motor sequence learning task. These observations challenge current theories of dyslexia. Hum Brain Mapp 34:2669–2687, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
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International Ophthalmology - Noninfectious inflammation of the posterior eye segment represents an important cause of visual impairment. It often affects relatively young people and causes a...  相似文献   
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