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51.
Correct preoperative diagnosis of a breast lesion is essential for optimal treatment planning. Our aim was to compare feasibility of fine needle aspiration cytology (FNAC) and core needle biopsy (CNB) in diagnosis of breast lesions. The special aim was to evaluate the extra costs and delay in surgical treatment due to unsuccessful preoperative biopsies. Diagnostic work-ups in 572 patients with 580 breast lesions were retrospectively evaluated. FNAC was the first biopsy method for 339 lesions, CNB for 241 lesions. The postoperative diagnosis was malignant for 503 lesions. The preoperative rate of definitely malignant diagnosis was 67% (194/289) for FNAC and 96% (206/214) for CNB (p < 0.0001), and 95% and 99%, respectively (p = 0.0173), when also suspicious findings were included. In patients with FNAC, an additional needle biopsy was performed for 93 and a surgical biopsy for 62 lesions. In the CNB group, a subsequent CNB was performed for 2 and a surgical biopsy for 33. The frequent need for additional biopsies raised the total expenses of FNAC over those of CNB. Multiple biopsies may also delay cancer surgery. It is therefore recommended to use CNB as the initial needle biopsy method.  相似文献   
52.
There is no standard therapy for malignant pleural mesothelioma (MPM), but recent reports have shown that extensive surgery combined with chemo- and radiotherapy prolongs the survival of selected patients with early stage disease. This emphasises the need for accurate staging procedures at diagnosis and reliable imaging methods to assess response to treatment. Computed tomography (CT) of the chest has been the standard imaging method for these purposes for the last decade, but it is limited in its ability to demonstrate accurately the platelike growth pattern of MPM within the thorax due to the partial volume effect on curved surfaces. In order to define the value of magnetic resonance imaging (MRI) in the imaging of MPM, we have compared the findings from 26 parallel paired CT and MRI scans of mesothelioma patients at various stages of the disease. MRI showed tumour spread into the interlobar fissures, tumour invasion of the diaphragm and through the diaphragm, and invasion of bony structures better than CT. Invasion of the chest wall and mediastinal soft tissue and tumour growth into the lung parenchyma were equally well seen on both imaging methods. CT was better for detecting the inactive pleural calcifications. MRI is a sensitive detector of the characteristic growth pattern and extension of MPM and we recommend its use more widely for the clinical management of MPM especially when evaluating tumour resectability and in research protocols when an accurate evaluation of disease extent is essential.  相似文献   
53.
Twelve nephrectomies (NEs) were performed in 12 pigs (11–17 kg). Total NE was performed on the left side and partial NE on the right side (lower third of the kidney), thus two-thirds of the total kidney volume was removed. Renal function was studied with 99mTc-diethylenetriaminepentaacetic acid (DTPA) renography and serum urea and creatinine levels preoperatively, and 1 and 2 weeks postoperatively. The pigs were imaged in each session for 30 min by collecting 10-s frames from a posteroanterior (PA) view of an anaesthesized animal. The injected activity was 37 MBq. Serial blood samples were taken from the subclavian vein at 0, 1, 2, 3, 5, 15, 25, 40, 60 and 120 min (six animals) after 99mTc-DTPA injection. The DTPA disappearance rate (DDR) was determined from these samples and in other cases (six animals) a blood sample at 20 min was used. The DDR was also determined from the dynamic gamma imaging data: Regions of interest (ROI) were upper body, spleen, heart and kidneys. The ROI analysis correlated well with the blood sampling data (r=0.97, P<0.0001). The reference values for pig DDRs were 0.99±0.08%/min. These values were 0.71±0.08%/min at 1 week postoperatively and 0.63±0.08%/min at 2 weeks. DTPA clearance rates were preoperatively 0.53±0.06 ml/s; at 1 week postoperatively 0.41±0.06 ml/s; and at 2 weeks 0.35±0.06 ml/s. There were no significant differences pre- and postoperatively in creatinine and urea concentrations. The DTPA clearance (ml/s) and disappearance rates (%/min) when determined per kidney area (cm2) increased significantly (P<0.001 at both 1 and 2 weeks); in 11 of 12 animals the function of the resected right kidney was higher than the split function of the whole right kidney preoperatively. Unilateral nephrectomy initiates a functional adaptation or a growth response in the contralateral kidney to compensate for the loss of a renal mass. These data also indicate that two-thirds of the kidney volume in young pigs can be removed without danger.  相似文献   
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Rock autobiographies have become increasingly popular since the 1990s. This article analyzes 31 mainstream rock autobiographies describing a wide variety of legal and illegal substances used and reckless behavior. Narrative analysis shows that books concentrate on recovering from addiction. The majority of writers have participated in some kind of treatment. Rock autobiographies use therapeutic vocabulary and borrow discursive elements from culturally familiar Alcoholics Anonymous texts recounting recovery stories. The analysis shows that drugs and alcohol are not associated with rebellion and authenticity as they once were in rock music. Surviving addiction has become a key theme of rock culture.  相似文献   
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In order to describe how humans represent meaning in the brain, one must be able to account for not just concrete words but, critically, also abstract words, which lack a physical referent. Hebbian formalism and optimization are basic principles of brain function, and they provide an appealing approach for modeling word meanings based on word co‐occurrences. We provide proof of concept that a statistical model of the semantic space can account for neural representations of both concrete and abstract words, using MEG. Here, we built a statistical model using word embeddings extracted from a text corpus. This statistical model was used to train a machine learning algorithm to successfully decode the MEG signals evoked by written words. In the model, word abstractness emerged from the statistical regularities of the language environment. Representational similarity analysis further showed that this salient property of the model co‐varies, at 280–420 ms after visual word presentation, with activity in regions that have been previously linked with processing of abstract words, namely the left‐hemisphere frontal, anterior temporal and superior parietal cortex. In light of these results, we propose that the neural encoding of word meanings can arise through statistical regularities, that is, through grounding in language itself.  相似文献   
58.
The purpose of the study was to evaluate prevalence, characteristic symptoms, and management of Chiari Malformation 1 (CM1).  相似文献   
59.
BACKGROUND AND PURPOSE: We assumed that patients with surgically treated aneurysmal subarachnoid hemorrhage (SAH) might have more lesions than those revealed by CT that could be visible on MR images. METHODS: We conducted a retrospective study of a series of 147 patients with aneurysmal SAH who were treated surgically within 3 days of the onset of SAH. One hundred four patients (mean age, 48.8 years) underwent MR imaging studies 2.1 to 5.6 years (mean, 3.3 years) postoperatively. RESULTS: Eighty-four (81%) patients presented a total of 152 areas of increased signal intensity on T2-weighted images, consistent with infarction; 48% of the patients had lesions in the frontal lobes. CT performed 3 months postoperatively revealed hypodense areas on the scans of only 57% of the patients and showed lesions in the frontal lobes of only 16% of the patients. CONCLUSION: Patients who undergo early surgery for aneurysmal SAH have more lesions than are revealed by CT. The difference is remarkable, especially in the frontal lobes.  相似文献   
60.
Introduction: Disorders of pulmonary tissue and pleura are visualized by findings in high‐resolution computed tomography (HRCT), and the impairment caused by these findings is assessed by pulmonary function tests. Our aim was to determine how some commonly used spirometric variables are related to certain HRCT signs, in order to find out which HRCT signs are associated with restrictive and which with obstructive ventilatory impairment. Methods: Altogether 590 asbestos‐exposed workers, 95% of whom were smokers or ex‐smokers, were studied with HRCT; 19 pathological signs were scored. Forced vital capacity (FVC), forced expiratory volume in 1 s (FEV1), FEV1/FVC ratio, forced expiratory flow at 50% of FVC (MEF50) and total lung capacity (TLC) were measured, and their relationship with HRCT signs was examined with bivariate correlations and multiple regression analysis. Results: FVC and TLC were negatively correlated with fibrosis score, parenchymal bands, extent of pleural thickenings and positively with widened retrosternal space. FEV1/FVC ratio was negatively correlated with emphysema types and widened retrosternal space and positively with parenchymal bands and subpleural nodules. Thickened bronchial walls did not separate between restrictive and obstructive ventilatory function. Conclusions: HRCT signs showed distinctive patterns in restrictive and obstructive ventilatory impairment. These results can be used to help to analyse the lung function of patients simultaneously exposed to asbestos and smoking, when this relationship requires elucidation. In addition, the results may be helpful in explaining some radiological findings.  相似文献   
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