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1.
The authors present three cases of vein of Galen aneurysmal malformations (VGAMs) diagnosed in infancy and submitted by the referring teams for stereotactic radiosurgery as the initial therapy (therapeutic doses ranging between 20–25 Gy and 40–50 Gy to the peak dose). After the conventional follow-up of 18–24 months, no change could be detected in the angioarchitecture of the lesions. All three cases were then referred for endovascular treatment and underwent embolization by the transarterial route using liquid adhesives (N-butyl cyanoacrylate). This resulted in complete anatomical exclusion of the lesion. Regardless of the theoretical efficiency of radiosurgery in the management of brain arteriovenous malformations, the present authors believe that transarterial embolization remains the treatment of choice in VGAMs. It offers a high rate of morphological cure and the best chances for normal neurocognitive development. The time required by radiosurgery to achieve a significant result is too long for developing and maturing brain and may not prevent the negative effects of the lesion, mainly in regard to hemo- and hydrodynamic disorders (atrophy, subcortical calcifications, etc.) created by the VGAM, thus leading to irreversible mental retardation.  相似文献   
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Summary The Gd-DTPA-enhanced magnetic resonance findings in two patients with herniated thoracic intervertebral discs are reported. The first patient was a 56-year-old woman with a small subligamentous T6-7 disc herniation, slightly lateralized to the right. The second patient was a 51-year-old man with a central and right posterolateral disc herniation, including a large calcified fragment, at the T8-9 level. The nonenhanced MR examination revealed the presence of an extradural mass lesion in both patients, impinging upon the dural sac and compressing and displacing the spinal cord posteriorly. The lesion was slightly hypointense on both T1- and T2-weighted spin echo sequences. Following intravenous injection of Gd-DTPA in a dosage of 0.1 mmol/kg body weight, enhancement of the posterior longitudinal ligament was noted and triangular areas of contrast uptake were seen to occur in the epidural space above and below the herniated disc. At surgery, they were found to correspond to dilated and congested epidural veins.  相似文献   
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Rammed earth is a sustainable material with low embodied energy. However, its development as a building material requires a better evaluation of its moisture-thermal buffering abilities and its mechanical behavior. Both of these properties are known to strongly depend on the amount of water contained in wall pores and its evolution. Thus the aim of this paper is to present a procedure to measure this key parameter in rammed earth or cob walls by using two types of probes operating on the Time Domain Reflectometry (TDR) principle. A calibration procedure for the probes requiring solely four parameters is described. This calibration procedure is then used to monitor the hygrothermal behavior of a rammed earth wall (1.5 m × 1 m × 0.5 m), instrumented by six probes during its manufacture, and submitted to insulated, natural convection and forced convection conditions. These measurements underline the robustness of the calibration procedure over a large range of water content, even if the wall is submitted to quite important temperature variations. They also emphasize the importance of gravity on water content heterogeneity when the saturation is high, as well as the role of liquid-to-vapor phase change on the thermal behavior.  相似文献   
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We report an anatomical-based association between conus medullaris pial arteriovenous shunt that drain caudally towards the lumbosacral area with very delayed onset of an acquired lumbar epidural shunt, draining secondarily towards intradural veins and responsible for a venous congestive myelopathy with identical clinical symptoms. These patients require close clinical and imaging follow-ups in order to propose adequate treatments before onset of irreversible neurological deficits. MRA should include the lumbo-sacral area in its field of view.  相似文献   
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Umbilical cord blood (UCB) provides immediate access to haemopoietic stem/progenitor cells (HSPC) but low cell number restricts use in full adult bone marrow reconstitution. This study investigated early ex vivo expansion kinetics of UCB AC133+ cells (2-4 x 10(4)/ml), mononuclear cells (MNC, 1-2 x 10(6)/ml) and AC133negative cells (AC133(neg), 2-4 x 10(4)/ml) in stroma-free 8 d liquid culture (fetal bovine serum-supplemented Iscove's-modified Dulbecco's medium (IMDM) with either 'K36EG'[c-Kit ligand, interleukin 3 (IL-3), IL-6, erythropoietin, granulocyte colony-stimulating factor] or 'TPOFL' (thrombopoietin, Flt-3 ligand). Cell enumeration, apoptosis assay and AC133/CD34/CD38 antigen immunophenotyping were performed at d 0, 3, 5 and 8. All three cell populations went through a proliferation lag phase between d 3 and d 5. AC133+ cells recovered better from lag phase with significantly higher fold increase (FI) when compared with MNC and AC133(neg) populations (K36EG FI: 15.04 +/- 5.46; TPOFL FI: 8.59 +/- 2.92, P < 0.05). After 8 d, populations lacking AC133+ cells were significantly more inclined to undergo apoptosis under proliferative conditions (P < 0.01). Also, when compared with K36EG, 8 d TPOFL-expanded AC133+ cells encompassed a significantly higher percentage of AC133+ and CD34+ early HSPC (K36EG: 20.50 +/- 2.36; TPOFL: 47.00 +/- 7.69; P < 0.05). In conclusion, TPOFL synergism demonstrated the potential for AC133+ HSPC ex vivo expansion inducing self-renewal, early HSPC maintenance and promoting cell survival status.  相似文献   
9.
Interval breast cancers (those diagnosed between recommended mammography screens) generally have poorer outcomes and are more common among women with dense breasts. We aimed to develop a risk model for interval breast cancer. We conducted a nested case–control study within the Melbourne Collaborative Cohort Study involving 168 interval breast cancer patients and 498 matched control subjects. We measured breast density using the CUMULUS software. We recorded first-degree family history by questionnaire, measured body mass index (BMI) and calculated age-adjusted breast tissue aging, a novel measure of exposure to estrogen and progesterone based on the Pike model. We fitted conditional logistic regression to estimate odds ratio (OR) or odds ratio per adjusted standard deviation (OPERA) and calculated the area under the receiver operating characteristic curve (AUC). The stronger risk associations were for unadjusted percent breast density (OPERA = 1.99; AUC = 0.66), more so after adjusting for age and BMI (OPERA = 2.26; AUC = 0.70), and for family history (OR = 2.70; AUC = 0.56). When the latter two factors and their multiplicative interactions with age-adjusted breast tissue aging (p = 0.01 and 0.02, respectively) were fitted, the AUC was 0.73 (95% CI 0.69–0.77), equivalent to a ninefold interquartile risk ratio. In summary, compared with using dense breasts alone, risk discrimination for interval breast cancers could be doubled by instead using breast density, BMI, family history and hormonal exposure. This would also give women with dense breasts, and their physicians, more information about the major consequence of having dense breasts—an increased risk of developing an interval breast cancer.  相似文献   
10.

Objectives

The aim of this study was to determine whether individual operator characteristics have an impact on reperfusion and procedural complication rates.

Background

Mechanical thrombectomy (MT) is a Level IA treatment in acute ischemic stroke (AIS) patients. The operator’s effect has been found to be an independent predictor for clinical outcome and technical performance in interventional cardiology.

Methods

From the ETIS (Endovascular Treatment in Ischemic Stroke) study, a prospective, multicenter, observational real-world MT registry, the authors included all AIS patients consecutively treated by MT between January 2012 and March 2017 in 3 high-volume comprehensive stroke centers by 19 operators. We assessed the effect of individual operator characteristics on successful reperfusion, defined as modified Thrombolysis In Cerebral Infarction 2b/3 at the end of MT, and procedural complications using multivariable hierarchical logistic regression models.

Results

A total of 1,541 patients with anterior and posterior AIS were enrolled (mean age 67 years; median NIHSS 16). There was a significant operator effect on successful reperfusion, with an intraclass correlation coefficient of 0.036 (p = 0.046), but not on complications (intraclass correlation coefficient = 0). There was a dose–response relationship between annual operator volume and successful reperfusion rate (p = 0.003) with an adjusted odds ratio for successful reperfusion equal to 2.52 (95% confidence interval: 1.37 to 4.64) for patients treated by an operator with an annual volume ≥40 MT/year compared with those treated by an operator with <14 MT/year (first tertile). Nevertheless, this result did not translate to better clinical outcomes.

Conclusions

Our data suggest that operator volume of MT/year has a positive impact on successful reperfusion in AIS patients, but not on clinical outcomes nor on complication rates. Further studies are warranted to investigate threshold procedure numbers associated with better outcomes.  相似文献   
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