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141.
People can quickly detect bilateral reflection in an image. This is true when elements of the same luminance are matched on either side of the axis (symmetry) and when they have opposite luminance polarity (anti‐symmetry). Using electroencephalography, we measured the well‐established sustained posterior negativity (SPN) response to symmetry and anti‐symmetry. In one task, participants judged the presence or absence of regularity (Regularity Discrimination Task). In another, they judged the presence or absence of rare colored oddball trials (Colored Oddball Task). Previous work has concluded that anti‐symmetry is only detected indirectly, through serial visual search of element locations. This selective attention account predicts that the anti‐symmetry SPN should be abolished in the Colored Oddball Task because there is no need to search for anti‐symmetry. However, this prediction was not confirmed: The symmetry and anti‐symmetry SPN waves were not modulated by task. We conclude that at least some forms of anti‐symmetry can be extracted from the image automatically, in much the same way as symmetry. This is an important consideration for models of symmetry perception, which must be flexible enough to accommodate opposite luminance polarity, while also accounting for the fact anti‐symmetry is often perceptually weaker than symmetry.  相似文献   
142.
Leptomeningeal metastases   总被引:3,自引:0,他引:3  
Leptomeningeal metastasis, also known as neoplastic meningitis, carcinomatous meningitis, and meningeal carcinomatosis, occurs when cancer cells gain access to cerebrospinal fluid pathways, travel to multiple sites within the central nervous system, settle, and grow. This disease has become an increasingly important late complication in oncology as patients survive longer, develop more brain metastases, and newer chemotherapies fail to penetrate the blood-brain barrier. The hallmark of clinical presentation is a cancer patient who complains of focal neurologic dysfunction and is found to have multifocal signs on neurologic examination. The clinical course is relentlessly progressive; treatment is limited and cures are the subject of case reports. This article reviews the clinical course of leptomeningeal metastasis and addresses recent developments in its pathophysiology, diagnosis, and treatment.  相似文献   
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We evaluated the safety and efficacy of image-guided radiofrequency ablation (RFA) using a triple-spiral-shaped electrode needle for unresectable primary or metastatic hepatic tumors. Thirty-four patients with 46 index tumors were treated. Ablation zone, morbidity, and complications were assessed. The lesions were completely ablated with an ablative margin of about 1 cm. Five patients (14.7%) with a lesion larger than 4.5 cm had local tumor progression after 1 month and were retreated. Hemothorax, as a major complication, occurred in 1 of 34 patients (3.0%) or 1 of 46 lesions ablated (2.2%). RFA using this new electrode needle can be effective in the treatment of large unresectable hepatic tumors.  相似文献   
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Background The optimal strategy for incorporating lymphatic mapping and sentinel lymph node biopsy into the management of breast cancer patients receiving neoadjuvant chemotherapy remains controversial. Previous studies of sentinel node biopsy performed following neoadjuvant chemotherapy have largely reported on patients whose prechemotherapy, pathologic axillary nodal status was unknown. We report findings using a novel comprehensive approach to axillary management of node-positive-patients receiving neoadjuvant chemotherapy. Methods We evaluated 54 consecutive breast cancer patients with biopsy-proven axillary nodal metastases at the time of diagnosis that underwent lymphatic mapping with nodal biopsy as well as concomitant axillary lymph node dissection after receiving neoadjuvant chemotherapy. All cases were treated at a single comprehensive cancer center between 2001 and 2005. Results The sentinel node identification rate after delivery of neoadjuvant chemotherapy was 98%. Thirty-six patients (66%) had residual axillary metastases (including eight patients that had undergone resection of metastatic sentinel nodes at the time of diagnosis), and in 12 cases (31%) the residual metastatic disease was limited to the sentinel lymph node. The final, post-neoadjuvant chemotherapy sentinel node was falsely negative in three cases (8.6%). The negative final sentinel node accurately identified patients with no residual axillary disease in 17 cases (32%). Conclusions Sentinel lymph node biopsy performed after the delivery of neoadjuvant chemotherapy in patients with documented nodal disease at presentation accurately identified cases that may have been downstaged to node-negative status and can spare this subset of patients (32%) from experiencing the morbidity of an axillary dissection.  相似文献   
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Of 379 severe acute respiratory syndrome coronavirus 2 samples collected in New York, USA, we detected 86 Omicron variant sequences containing Delta variant mutation P681R. Probable explanations were co-infection with 2 viruses or contamination/amplification artifact. Repeated library preparation with fewer cycles showed the P681R calls were artifactual. Unusual mutations should be interpreted with caution.  相似文献   
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This study aimed to examine the associations of lifetime traumatic experience with presurgery and postsurgery eating pathology and postoperative weight loss in a sample of adult bariatric surgery patients using electronic medical record (EMR) data. Presurgery lifetime exposure to traumatic event, presurgery and postsurgery dysfunctional eating patterns, and post‐operative total and excess weight losses were extracted from electronic medical records of 200 adult bariatric surgery patients in 2013 and 2014. Logistic regression analyses were conducted. During their lifetime, 60.5% of the patients (81.5% women, age = 44.4 ± 11.5 years; BMIpre = 44.9 ± 5.5 kg/m2) reported that they were exposed to a traumatic event. Before surgery, trauma exposure was associated with impulsive, compulsive, or restrictive eating patterns (OR = 2.40), overeating or disturbed eating (OR = 1.55), and grazing or night eating behaviours (OR = 1.72). After surgery, trauma exposure was associated with lower total weight loss at 6 (OR = 2.06) and 24 months (OR = 2.06), and to overeating or disturbed eating (OR = 1.53) 12 months after surgery. Bariatric surgery candidates with a history of trauma exposure could benefit from closer medical, dietetic, and/or psychological follow‐up care to avoid insufficient postoperative weight loss as well as reappearance of dysfunctional eating patterns after surgery.  相似文献   
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