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101.
Apparent diffusion coefficients of breast tumors: clinical application.   总被引:2,自引:0,他引:2  
PURPOSE: To evaluate the usefulness of apparent diffusion coefficient (ADC) for the differential diagnosis of breast tumors and to determine the relation between ADC and tumor cellularity. MATERIALS AND METHODS: One hundred and thirty-six female patients (age range, 17-83 years; average age, 51.7 years) with 140 histologically proven breast tumors underwent diffusion-weighted magnetic resonance (MR) imaging (DWI) using the spin-echo echo-planar technique, and the ADCs of the tumors were calculated using 3 different b values, 0, 500, and 1000 s/mm(2). The diagnoses consisted of fibroadenoma (FA, n=16), invasive ductal carcinoma, not otherwise specified (IDC, n=117), medullary carcinoma (ME, n=3) and mucinous carcinoma (MU, n=4). Tumor cellularity was calculated from surgical specimens. The ADCs of breast tumors and cellularity were compared between different histological types by analysis of variance and Scheffe's post hoc test. The correlation between tumor cellularity and ADC was analyzed by Pearson correlation test. RESULTS: Significant differences were observed in ADCs between FA and all types of cancers (P<0.05) and between MU and other types of cancers (P<0.01) and in cellularity between FA and cancers except MU (P<0.01) and between MU and other types of cancers (P<0.01). There was an inverse correlation between ADC and tumor cellularity (P<0.01, r(2)=0.451). CONCLUSIONS: The ADC may potentially help in differentiating benign and malignant breast tumors. Tumor ADC correlates inversely with tumor cellularity.  相似文献   
102.
The cytoprotective effect of prostaglandins (PG) was evaluated by in vivo 31P MR spectroscopy. Twenty rabbits were divided into two groups; the control group given physiological saline, and the PG group given prostaglandin E1 (0.5 μg/kg/min). Each solution was infused for 8 min, after which complete hepatic ischemia was induced for 20 min, followed by reperfusion for 40 min. During ischemia, β-ATP decreased to 23.6% and 42.3%, phosphomonoester increased to 260% and 200% of their initial values in the control and the PG groups, respectively. Inorganic phosphate also increased. After reperfusion, β-ATP recovered to 65.2% and 96.5%, phosphomonoester to 130% and 110%, inorganic phosphate to 140% and 120% in the control and PG groups, respectively. The changes during ischemia were significantly smaller and the recoveries during reperfusion were more complete in the PG group. These results may confirm the cytoprotective effect of prostaglandins by in vivo 31P-MR spectroscopy.  相似文献   
103.
A 34-year-old male patient with epigastralgia was found to have an esophageal submucosal tumor based on an endoscopic evaluation 6 years previously. Because an unusual appearance composed of a heterogenous solid area and a cyst area on the endoscopic ultrasonogram and the increased size of the tumor on esophagograms over the past 3 years were suggestive of a malignant character, an operation was thus indicated. The tumor, which measured 3.5 × 2.5 × 2.0 cm in size, was enucleated using videoassisted thoracic surgery and was diagnosed to be a very rare myxoid leiomyosarcoma with a thorough pathologic examination. To our knowledge, this is only the second case of esophageal myxoid leiomyosarcoma reported in the literature. We thus consider this case, which demonstrated an unique appearance on an endoscopic ultrasonogram, to possibly be beneficial to the overall diagnostic analysis of esophageal submucosal tumors.  相似文献   
104.
A 54-year-old man with a 30-year history of chronic alcoholism was admitted to our hospital suffering from dyspnea and left-sided chest pain. A chest radiograph revealed pleural effusion. Computed tomography revealed a pancreatic pseudocyst in the tail of the pancreas spreading out to the posterior mediastinum and the left pleural cavity. The laboratory findings of pleural effusion were as follows: amylase, 118400 IU/1; protein, 4.6 g/dl; class I in cytology. Despite a reduction in the pleural effusion by conservative therapy, left back pain and a recurrence of the pleural effusion were observed after oral intake was re-initiated. A distal pancreatectomy and ligation of the pancreaticopleural fistula were thus performed on the 75th hospital day. The patient made a complete recovery from pancreatic pleural effusion and has now been well for 9 years.  相似文献   
105.
106.
Abstract: Background/Aim: To investigate the mode of progression of combined hepatocellular carcinoma and cholangiocarcinoma (cHCC‐CC). Methods: An immunohistochemical study for E‐cadherin (ECD) and alpha‐ and beta‐catenins was performed on 29 cases of cHCC‐CC. Results: Reduced expression of ECD was significantly correlated with the tumour grade of the hepatocellular carcinoma (HCC) and cholangiocarcinoma (CC) components, intrahepatic metastasis (IM) of HCC, IM of CC, and vascular invasion of CC (p < 0.05, respectively). There was a significant relationship between the reduced expression of beta‐catenin and the tumour grade of HCC components (p < 0.05). Cases showing concurrent intrahepatic metastasis composed of HCC, CC, or both, numbered 6, 5, and 2, respectively. The expression patterns of ECD and beta‐catenin of IM were similar to those of primary lesion in most cases. On the other hand, expression of ECD and beta‐catenin of IM of HCC component were preserved, even though those of the primary sites were reduced in two cases and one case, respectively. ECD and beta‐catenin were significantly correlated with tumour differentiation and tumour progression. Conclusions: Preserved or recovered ECD and beta‐catenin expression may be of beneficial effect for re‐establishing the tissue architecture at the metastatic site.  相似文献   
107.
The cytokeratins phenotype is largely preserved during neoplastic transformation and tumor development. We evaluated the immunoreactivity of biliary epithelial markers keratin 903 and cytokeratin 7 and 19 for intrahepatic cholangiocarcinoma, and compared the results with those for biliary dysplasia and hepatocellular carcinoma. Reactivity with keratin 903 was weakly expressed and increased after the expression of cytokeratin 7 and 19 during human intrahepatic bile duct development. More than 80% of cases of biliary dysplasia showed positive reactivity with keratin 903. Of the 30 cases of hepatocellular carcinoma, 3 (10%), 6 (20%), and 1 (3%) showed positive reactivity with Keratin 903 and cytokeratin 7 and 19, respectively. Among the 73 cases of intrahepatic cholangiocarcinoma, 54 (74%), 66 (90%), and 61 (84%) showed positive reactivity with keratin 903 and cytokeratin 7 and 19, respectively. On clinicopathologic examination of intrahepatic cholangiocarcinomas, reduced keratin 903 reactivity was significantly higher in tumors with an expansive growth pattern (P <.0001), in those with medullary-type stromal reaction (P =.0327), in those without perineural invasion (P =.0001), and in those without lymph node metastasis (P =.0015). In addition, the reactivity with Keratin 903 was directly correlated with expression of cytokeratin 7 and 19 (P =.0153 and P <.0001, respectively). Cases showing reduced keratin 903 reactivity were characterized by a distinctive morphology indicating an hepatocellular carcinoma-like pattern. Multivariate analysis of overall survival revealed that keratin 903 reactivity was a significantly independent prognostic factor. In conclusion, patients with intrahepatic cholangiocarcinoma showing reduced keratin 903 reactivity had a favorable prognosis. Remarkably, the cytokeratin phenotype of intrahepatic cholangiocarcinoma was correlated with the morphologic appearance of intrahepatic cholangiocarcinoma.  相似文献   
108.
109.
We report on the sensing stability of quantum nanosensors in aqueous buffer solutions for the two detection schemes of quantum decoherence spectroscopy and nanoscale thermometry. The electron spin properties of single nitrogen-vacancy (NV) centers in 25 nm-sized nanodiamonds have been characterized by observing individual nanodiamonds during a continuous pH change from 4 to 11. We have determined the stability of the NV quantum sensors during the pH change as the fluctuations of ±12% and ±0.2 MHz for the spin coherence time (T2) and the resonance frequency (ω0) of their mean values, which are comparable to the instrument error of the measurement system. We discuss the importance of characterizing the sensing stability during the pH change and how the present observation affects the measurement scheme of nanodiamond-based NV quantum sensing.

We report on the sensing stability of quantum nanosensors in aqueous buffer solutions for the two detection schemes of quantum decoherence spectroscopy and nanoscale thermometry.  相似文献   
110.
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