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1.
This report describes a variant of McKusick‐Kaufman syndrome presenting with a large fetal abdominal cyst of hydrometrocolpos at 37 weeks of gestation. The diagnosis was based on the ultrasound findings of a large homogeneous hypoechoic cyst (diameter of >10 cm) with incomplete septum, thickened wall, superiorly connecting to the dilated uterus, consistent with hydrometrocolpos. Additionally, pre‐axial mirror polydactyly of the left foot was suspected. Postnatal examination/work‐up confirmed the prenatal findings. This is the first report of prenatal diagnosis of hydrometrocolpos with complex polydactyly of mirror image pre‐axial duplications containing nine toes instead of six‐toe postaxial polydactyly.  相似文献   
2.
The well-designed network structure of synthetic polypyrrole (PPy) nanoparticles embedded on a nitrogen-doped graphene (N-rGO) surface was utilized as a cathode for aqueous zinc-ion hybrid supercapacitors. Owing to the combination of the redox surface of PPy and the two-dimensional network structure of N-rGO, the PPy/N-rGO cathode affords rapid transport channels for Zn2+ ion adsorption/desorption and a faradaic reaction toward the synergistic composite materials. Subsequently, the constructed zinc-ion hybrid supercapacitors with the optimized PPy/N-rGO cathode composites deliver the highest capacity of 145.32 mA h g−1 at 0.1 A g−1 and the maximum energy density of 232.50 W h kg−1 at a power density of 160 W kg−1. Besides this, excellent cycling stability of 85% retention after 10 000 charge–discharge cycles at 7.0 A g−1 was achieved. The high-rate capabilities with long life cycle performance of these novel zinc-ion hybrid supercapacitors could find practical use in a wide range of applications, ranging from next-generation electronic devices to large-scale stationary energy storage.

The well-designed network structure of synthetic polypyrrole (PPy) nanoparticles embedded on a nitrogen-doped graphene (N-rGO) surface was utilized as a cathode for aqueous zinc-ion hybrid supercapacitors.  相似文献   
3.

Objective

To determine the validity of sonographic pattern recognition in the diagnosis of mature cystic teratoma.

Methods

Consecutive patients scheduled for elective surgery for adnexal masses were included in the study. All patients underwent transabdominal ultrasound with color extended-flow mapping within 24 hours prior to surgery. Examinations were performed by the same sonographer to identify benign cystic teratoma. The final diagnoses were based on histopathologic findings.

Results

A total of 329 consecutive patients were recruited; 23 were excluded because the masses were not adnexal masses. Of the remaining 306 patients, 36 masses were found to be mature cystic teratomas and 270 were nonteratomas. Sonographic pattern recognition showed a sensitivity of 94.4% and a specificity of 98.2%.

Conclusion

Sonographic pattern recognition using transabdominal ultrasound with color extended-flow mapping can accurately diagnose mature cystic teratoma.  相似文献   
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Fractal analysis was used to quantify changes in trabecular bone induced through the use of a rat tail-suspension model to simulate microgravity-induced osteopenia. Fractal dimensions were estimated from digitized radiographs obtained from tail-suspended and ambulatory rats. Fifty 4-month-old male Sprague-Dawley rats were divided into groups of 24 ambulatory (control) and 26 suspended (test) animals. Rats of both groups were killed after periods of 1, 4, and 8 weeks. Femurs and tibiae were removed and radiographed with standard intraoral films and digitized using a flatbed scanner. Square regions of interest were cropped at proximal, middle, and distal areas of each bone. Fractal dimensions were estimated from slopes of regression lines fitted to circularly averaged plots of log power vs. log spatial frequency. The results showed that the computed fractal dimensions were significantly greater for images of trabecular bones from tail-suspended groups than for ambulatory groups (p < 0.01) at 1 week. Periods between 1 and 4 weeks likewise yielded significantly different estimates (p < 0.05), consistent with an increase in bone loss. In the tibiae, the proximal regions of the suspended group produced significantly greater fractal dimensions than other regions (p < 0.05), which suggests they were more susceptible to unloading. The data are consistent with other studies demonstrating osteopenia in microgravity environments and the regional response to skeletal unloading. Thus, fractal analysis could be a useful technique to evaluate the structural changes of bone.  相似文献   
7.
The objective of this series was to describe a simple rule for prenatal diagnosis of total anomalous pulmonary venous return (TAPVR). Fourteen fetuses had a prenatal diagnosis of TAPVR by the simple rule, including the following components: (1) the major criterion, which was the absence of a connection between the pulmonary vein and the left atrium; and (2) at least 1 of the following minor criteria: (a) the presence of a vascular confluence behind the atria, (b) abnormal spectral Doppler waveforms in the pulmonary veins, (c) a smooth posterior wall of the left atrium, (d) increased retroatrial space, (e) a dilated coronary sinus (cardiac type), (f) a dilated superior vena cava or brachiocephalic vein, and (g) an additional vessel on the 3‐vessel/3‐vessel and trachea view or a vertical descending vein. All were accurately diagnosed, and none were missed by the diagnosis. In summary, the simple rule described is helpful in increasing the number of accurate prenatal diagnoses of TAPVR.  相似文献   
8.
Impetigo herpetiformis is a rare disease and its occurrence is specific for pregnancy. The lesions are characterized by sterile, pustular eruptions. The disorder is usually seen in the third trimester, but cases of impetigo herpetiformis appearing in the first trimester have also been reported. The lesions are expected to disappear after birth, but the disorder may recur during subsequent pregnancies. In this case report we discuss a 28-year-old pregnant woman, G3P1011, with a history of impetigo herpetiformis in the first pregnancy, who presented with generalized pustular lesions at 30 weeks' gestation. Her disease responded poorly to corticosteroids and was more severe than in the previous pregnancy. She delivered prematurely at 34 weeks' gestation and then received aggressive postpartum treatment with methotrexate, resulting in a dramatic response. This case supports the current understanding that recurrent impetigo herpetiformis in subsequent pregnancy tends to be more severe and to have an earlier onset. Additionally, it provides additional evidence that methotrexate may be used as an alternative treatment for impetigo herpetiformis in the case of a poor response to corticosteroids.  相似文献   
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Objective. There are situations in which standard echocardiography does not adequately define the aortic arch. We sought to determine what additional information could be gained by analyzing abdominal aortic Doppler flows in coarctation. Design. Previously recorded echocardiographic data were reviewed in 70 controls and 248 patients with coarctation, including abdominal aortic values for pulsatility indices, pulse delay, and presence of early diastolic reversal. Ability of these variables to distinguish controls from coarctation patients and to assess coarctation severity was assessed. Results. Corrected maximum instantaneous gradient and all abdominal aortic flow variables were associated with severity of obstruction. Early diastolic reversal was universally absent in significant coarctation. Threshold values for other parameters associated with significant obstruction were: corrected pulse delay ≥3.4 msec1/2, pulsatility index <2.0, and systolic to diastolic velocity ratio <3.6. A combined abdominal aortic “variable” (absence of early diastolic reversal and corrected pulse delay ≥2.8 msec1/2) was found to be the best predictor of clinical coarctation status (positive predictive value = 93%, negative predictive value = 88%). Conclusions. In the absence of a ductus arteriosus, abdominal aortic Doppler parameters can reliably predict the presence of significant coarctation. When early diastolic reversal was present, obstruction was always absent. Lack of early diastolic reversal with a prolonged pulse delay was the best predictor of significant obstruction. Abdominal aortic Doppler evaluation should become a routine part of the evaluation of patients with known or suspected coarctation.  相似文献   
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