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Conventional magnetic resonance imaging (cMRI) is often used to aid the diagnosis of progressive supranuclear palsy (PSP) and multiple system atrophy (MSA), but its ability to predict the histopathological diagnosis has not been systematically studied. cMRI from 48 neuropathologically confirmed cases, including PSP (n = 22), MSA (n = 13), Parkinson's disease (PD) (n = 7), and corticobasal degeneration (n = 6), and controls (n = 9) were assessed blinded to clinical details and systematically rated for reported abnormalities. Clinical diagnosis and macroscopic postmortem findings were retrospectively assessed. Radiological assessment of MRI was correct in 16 of 22 (72.7%) PSP cases and 10 of 13 (76.9%) MSA cases with substantial interrater agreement (Cohen's kappa 0.708; P < .001); no PSP case was misclassified as MSA or vice versa. MRI was less sensitive but more specific than clinical diagnosis in PSP and both more sensitive and specific than clinical diagnosis in MSA. The “hummingbird” and “morning glory” signs were highly specific for PSP, and “the middle cerebellar peduncle sign” and “hot cross bun” for MSA, but sensitivity was lower (up to 68.4%) and characteristic findings may not be present even at autopsy. cMRI, clinical diagnosis, and macroscopic examination at postmortem have similar sensitivity and specificity in predicting a neuropathological diagnosis. We have validated specific radiological signs in pathologically confirmed PSP and MSA. However, the low sensitivity of these and macroscopic findings at autopsy suggest a need for imaging techniques sensitive to microstructural abnormalities without regional atrophy. © 2012 Movement Disorder Society  相似文献   
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Background

To achieve T-downstaging and better resectability in locally advanced rectal cancer, neoadjuvant radiochemotherapy (RCT) has become the current standard of treatment. A variety of schemes have been used. This study investigates which scheme had the best effect on these parameters.

Methods

Our institution is a referral center for locally advanced rectal cancer. Different neoadjuvant radiochemotherapy regimens were administered: long course radiotherapy (RTH), 5-FU and leucovorin (5FUBolus), a combination of capecitabine and oxaliplatin (CORE), and capecitabine only (CAP). Selection of patients for 1 of the regimens was based on hospital policy rather than patient or tumor characteristics.

Results

The data of 504 consecutive patients (n?=?181 T3+, n?=?323 T4) without metastatic disease (cM0) who underwent surgery for advanced rectal carcinoma between 1994 and 2010 were reviewed. The RTH, 5FUBolus, CORE, and CAP scheme were administered to 106, 137, 155, and 106 patients, respectively. Odds ratios for downstaging were less effective for RTH, 5FUBolus, and CAP (0.31, 0.44, and 0.31; P?P?=?.003) or CRM+ resection (3.78, 2.73, 1.34; P?=?.001) were also in favor of the CORE. Hazard ratios for CSS were significantly better for the CORE scheme.

Conclusions

Downstaging with neoadjuvant treatment results in an increased number of radical resections. In our study, the combination of capecitabine and oxaliplatin appears to be the most effective regimen for locally advanced rectal cancer tumors. However, longer follow-up will be necessary to confirm this conclusion.  相似文献   
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A series of 6 infants subjected to child abuse is presented in whom contusional tears of subcortical white matter were detected during life by intracranial sonography. The sonographic appearances of this highly pathognomonic marker of shaking injury are described for the first time and their significance discussed. On the basis of our experience we suggest that high resolution cranial sonography is an extremely valuable part of the diagnostic work up in cases of suspected non-accidental injury.  相似文献   
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Splenosis is an unusual condition representing auto-transplantation of splenic tissue following splenic trauma or surgery. When detected on imaging studies, the splenosis deposits are usually misinterpreted as pathological masses. We present a case where a pelvic mass incidentally visualized on an MRI examination, was proven to represent a deposit of splenosis by contrast enhanced ultrasound (CEUS). CEUS demonstrated persistent late-phase enhancement characteristic of splenic tissue. Ultrasound practitioners should be aware of this condition when an unusual abdominal or pelvic mass is encountered in a patient with a history of splenic trauma or surgery. CEUS is ideally suited to confirming the diagnosis.  相似文献   
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Until recently, the bronchial circulation has been relatively ignored in the research and clinical arenas, perhaps because of its small volume and seeming dispensability relative to the pulmonary circulation. Although the bronchial circulation only receives around 1% of the cardiac output in health, it serves functions that are critical to maintaining airway and lung function. The bronchial circulation also plays an important role in many lung and airway diseases; through its ability to increase in size, the bronchial circulation is able to provide lung parenchymal perfusion when the pulmonary circulation is compromised, and more recently the role of the bronchial circulation in the pathogenesis of inflammatory airway disease has been explored. Due to the anatomic variability and small volume of the bronchial circulation, much of the research to date has necessitated the use of animal models and invasive procedures. More recently, non‐invasive techniques for measuring bronchial blood flow in the mucosal microvascular network have been developed and offer a new avenue for the study of this circulation in humans. In conjunction with molecular research, measurement of airway blood flow (Qaw) may help elucidate the role of the bronchial circulation in inflammatory airway disease and become a useful tool for monitoring therapy. Pediatr Pulmonol. 2010; 45:1–13. © 2009 Wiley‐Liss, Inc.  相似文献   
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