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This study assessed the utility of scintimammography using a standard gamma-camera and a dedicated breast camera as an adjuvant to mammography and clinical examination. METHODS: The study population comprised 37 patients with dense breasts and a family or personal history of breast cancer. The subjects had no suggestive clinical or mammographic findings. After intravenous administration of (99m)Tc-sestamibi, the patients were imaged using a conventional gamma-camera and a dedicated breast camera that allowed breast compression during image acquisition. Images were interpreted independently by 2 reviewers. All patients with positive scintimammography findings underwent biopsy. RESULTS: Dedicated breast camera results were positive in 13.5% (5/37) of patients. Biopsy of these 5 patients yielded 3 carcinomas: an infiltrating lobular carcinoma, a ductal carcinoma in situ, and an infiltrating tubular carcinoma. These 3 carcinomas were undetectable by clinical breast examination or mammography, even on retrospective review. Only one of these, the tubular carcinoma, was readily detectable by the standard gamma-camera. CONCLUSION: Scintimammography using a dedicated breast camera may augment mammography and clinical breast examination for the subset of women who have dense breast tissue and are at high risk of breast cancer.  相似文献   
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Voso MT  Scardocci A  Guidi F  Zini G  Di Mario A  Pagano L  Hohaus S  Leone G 《Blood》2004,103(2):698-700
Death-associated protein kinase (DAP-kinase), a proapoptotic serine/threonine kinase, is a candidate tumor suppressor gene. We studied the methylation status of DAP-kinase of 194 bone marrow samples from 160 patients with acute myeloid leukemia (AML) and 34 with a myelodysplastic syndrome (MDS) at the time of initial diagnosis by polymerase chain reaction (PCR). Hypermethylation of DAP-kinase was present in 27.5% (44 of 160) of AML and in 47% (16 of 34) of MDS specimens and significantly correlated to loss of DAP-kinase expression (P =.008). It was significantly more frequent in AML secondary to therapy for other malignancies (s-AML; 14 of 29, 48.3%), as compared to de novo AML (30 of 131, 22.9%, P =.01). DAP-kinase hypermethylation in AML was associated with myelodysplastic changes in the bone marrow at the time of the initial diagnosis (P =.002) and with the presence of cytogenetic abnormalities (P =.02). Alteration in the apoptotic response due to the loss of DAP-kinase function may be an early event in the transformation pathway to secondary leukemia via myelodysplasia.  相似文献   
135.
RATIONALE AND OBJECTIVES: Quantitative criteria for the Breast Imaging Reporting and Data System (BI-RADS) mammographic density categories have recently been defined as <25% dense for almost entirely fatty, 25%-50% dense for scattered fibroglandular densities, 51%-75% for heterogeneously dense, and >75% dense for the extremely dense category. The purpose of this study is to compare the range of percent mammographic densities with radiologist-assigned BI-RADS mammographic density categories and compare with the recently issued definitions. MATERIALS AND METHODS: In this study, 200 consecutive negative analog screening mammograms were assigned BI-RADS mammographic density categories independently by three radiologists blinded to the other readers' density assignment. Quantitative assessment of percent mammographic density was performed using previously validated software. RESULTS: All three readers agreed on BI-RADS mammographic density categories in 98 cases (49%), and two of three readers agreed in all 200 cases. Using two reader's consensus, median mammographic density (range) was 6.0% (0.5%-19.2%) for fatty, 14.8% (1.2%-52.7%) for scattered densities, 51.2% (15.9%-82.2%) for heterogeneously dense, and 78.4% (60.1%-87.9%) for extremely dense breasts. The percent mammographic density ranges for fatty and extremely dense breasts correlated well with BI-RADS definitions, whereas the ranges of densities in the scattered and heterogeneously dense categories were considerably broader. CONCLUSION: Fatty and extremely dense BI-RADS categories compare relatively well to defined criteria, and therefore may be helpful in breast cancer risk models. Scattered fibroglandular densities and heterogeneously dense categories have broad percent mammographic density ranges and may not function well in breast cancer risk models.  相似文献   
136.
OBJECTIVE: To determine whether there is an association between abnormal primary peristalsis in the esophagus and gastroesophageal reflux (GER) on barium studies. METHODS: A computerized search of radiologic reports revealed 151 patients with esophageal dysmotility (characterized by intermittently decreased or absent peristalsis in the esophagus on upper gastrointestinal tract examinations) who fulfilled our study's entry criteria. These 151 patients were stratified into two groups depending on whether this dysmotility was associated with nonperistaltic contractions (NPCs): 92 patients had no NPCs (Dysmotility and No NPCs Group) and 59 had NPCs (Dysmotility and NPCs Group). An age-matched control group of 92 patients with normal motility was also generated from the radiologic reports. The reports were also reviewed for the presence and degree of GER and other complications of GER. The frequency and degree of GER were tabulated for each group, and the data were analyzed using a Pearson chi square test to determine if significant differences were present in the frequency and degree of GER or other findings among the groups. RESULTS: The frequency of GER was significantly higher in patients with abnormal peristalsis and no NPCs than in controls (p = 0.02). When GER was stratified based on the degree of reflux, the frequency of moderate-to-marked GER was significantly higher in patients with abnormal peristalsis and no NPCs than in patients with abnormal peristalsis and NPCs (p = 0.01) or in controls (p = 0.0031). The frequency of reflux esophagitis also was significantly higher in patients with abnormal peristalsis and no NPCs than in controls (p = 0.04). CONCLUSION: Our findings suggest that patients with esophageal dysmotility characterized by intermittently decreased or absent peristalsis without NPCs have a significantly higher frequency and degree of GER than patients with normal motility. The presence of this specific form of esophageal dysmotility on barium studies therefore should suggest underlying reflux disease.  相似文献   
137.
The schizophrenia syndrome is clinically characterized by abnormal constructions of meaning during comprehension (delusions), perception (hallucinations), action (disorganized and non-goal-directed behavior) and language production (thought disorder). This article provides an overview of recent studies from our laboratory that have used event-related potentials and functional magnetic resonance imaging to elucidate abnormalities in temporal and spatial patterns of neural activity as meaning is built from language and real-world visual events in schizophrenia. Our findings support the hypothesis that automatic activity across semantic memory spreads further within a shorter period of time in thought-disordered patients, relative to non-thought-disordered patients and healthy controls. Neuroanatomically, increased activity to semantic associates is reflected by inappropriate recruitment of temporal cortices. In building meaning within sentences, the fine balance between semantic memory-based mechanisms and semantic-syntactic integration (dictating "who does what to whom") is disrupted, such that comprehension is driven primarily by semantic memory-based processes. Neuroanatomically, this imbalance is reflected by preserved (and sometimes increased) activity within temporal and inferior prefrontal cortices, but abnormal modulation of dorsolateral prefrontal and parietal cortices. In building meaning across sentences (discourse), patients fail to immediately construct coherence links, but may show inappropriate recruitment of temporal and inferior prefrontal cortices to incoherent discourse, again reflecting inappropriate semantic memory-based processing (abnormal inferencing). Finally, these abnormalities may generalize to real-world visual event comprehension, where patients show reduced neural activity in determining relationships around goal-directed actions, and comprehension is again dominated by semantic memory-based mechanisms.  相似文献   
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Optimal management of rectal cancer depends on obtaining accurate and detailed staging information at the time of diagnosis. The majority of this comes from radiological staging investigations such as computed tomography (CT), magnetic resonance imaging (MRI) and endoanal ultrasound (EAUS). Whilst there is little debate on the use of CT to assess distant spread of disease, there is still variation in the use of MRI or EAUS in the local staging of rectal cancer. Both techniques have their roles but MRI is better able to visualise the entire rectum and mesorectum as well as accurately identify the circumferential resection (CRM) margin in relation to the tumour edge. Breach of the CRM is one of the most important predictors of local recurrence and knowledge of its relationship to the tumour determines initial management. MRI has additional advantages in being able to identify other poor prognostic factors such as extramural venous invasion (EMVI) and mucin deposition, which further influence oncological treatment. It also provides the surgeon with accurate information on the relationship of the tumour to surrounding structures and the sphincter complex which is important for surgical planning. This review highlights the important determinants of local staging in rectal cancer and presents the evidence to answer the question as to which is a better imaging modality—MRI or EAUS?  相似文献   
140.
Chronic low back pain is a major cause of disability and health care costs. Effective treatments are inadequate for many patients. Animal models are essential to further understanding of the pain mechanism and testing potential therapies. Currently, a number of preclinical models have been developed attempting to mimic aspects of clinical conditions that contribute to low back pain (LBP). This review focused on describing these animal models and the main behavioral tests for assessing pain in each model. Animal models of LBP can be divided into the following five categories: Discogenic LBP, radicular back pain, facet joint osteoarthritis back pain, muscle‐induced LBP, and spontaneous occurring LBP models. These models are important not only for enhancing our knowledge of how LBP is generated, but also for the development of novel therapeutic regimens to treat LBP in patients. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:1305–1312, 2018.
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