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排序方式: 共有1556条查询结果,搜索用时 15 毫秒
1.
Accuracy evaluation of image registration and segmentation tools used in conformal treatment planning of prostate cancer. 总被引:1,自引:0,他引:1
Stefania Pallotta Marta Bucciolini Serenella Russo Cinzia Talamonti Talamonti Cinzia Giampaolo Biti 《Computerized medical imaging and graphics》2006,30(1):1-7
Segmentation and registration tools are commonly used in radiotherapy for target and at risk organs localisation. In this work the performances of three different segmentation tools and of a surface matching registration technique, used on computed tomography (CT) and magnetic resonance (MR) images for the treatment planning of conformal prostate carcinoma, are studied. The accuracy of the segmentation and registration tools was evaluated by phantom experiment and on patient data, respectively. A preliminary estimate of MR image distortion was also performed. 相似文献
2.
Imad Sheiban M. D. Dino Casarotto Giampaolo Trevi Paolo Benussi Alberto Marini Roberto Accardi Antonio Motta Massimo Brunelli Claudio Muneretto Alessandro Tenuti Ludovico Antonio Scuro 《Cardiovascular and interventional radiology》1987,10(3):157-161
The accuracy of two-dimensional echocardiography in the detection of intracardiac masses was verified in 334 patients who
underwent cardiac catheterization in our laboratory over 21 consecutive months. A complete two-dimensional echocardiographic
(2DE) examination was performed a day before catheterization. The presence or absence of a mass was verified at surgery in
77 patients who successively underwent mitral or aortic valve replacement (51), left ventricular aneurysmectomy with or without
myocardial revascularization (25), and resection of atrial myxoma (2). In 32 patients 2DE revealed the presence of a mass-left
or right atrial thrombi in 12, left atrial myxoma in 2, left ventricular thrombi in 16, and endocardial vegetations in 2.
The other 45 patients were free of intracardiac masses on 2DE. Anatomic verification at surgery revealed the presence of an
intracardiac mass in 34 patients. In 30 (true positives) of these, 2DE revealed the mass as well, and in 4 (false negatives)
the presence of a mass had not been identified by 2DE. In 2 patients (false positives) the predicted mass was not found at
surgery. Absence of a mass was correctly predicted by 2DE in 41 patients (true negatives). Thus 2DE detected intracardiac
masses with sensitivity of 88.2% and a specificity of 95.3%. We recommend that 2DE be performed in all patients prior to hemodynamic
study and/or cardiac surgery to enable safer management of patients with intracardiac masses during cardiac catheterization
and/or cardiac surgery. 相似文献
3.
L M Cavallo F Briganti P Cappabianca F Maiuri V Valente F Tortora A Volpe A Messina A Elefante E De Divitiis 《Minimally invasive neurosurgery》2004,47(3):145-150
Two hundred and fifty consecutive patients operated on by an endoscopic endonasal transsphenoidal approach were retrospectively analyzed in order to evaluate hemorrhagic vascular complications occurring during or after the surgical procedure and their appropriate management. Vascular complications of endoscopic transsphenoidal surgery are identical to those of a microsurgical transsphenoidal approach. Damage to the sphenopalatine artery and to the internal carotid artery (ICA), which are the most frequent vascular troubles, may require technical tricks because of some aspects connected to the approach itself and of the physical properties of the endoscope. Furthermore, the progress in interventional neuroradiology in the last decades offers new solutions in respect to the past, where the use of the surgical microscope was already a tremendous progress. The anatomic substrate of each complication is discussed, along with the peculiar surgical details related to it. 相似文献
4.
O Goletti M Chiarugi P Buccianti A Tortora M Castagna P Del Guerra P Viacava E Cavina 《Acta chirurgica》1992,158(1):55-57
In a 30-year-old man with Zollinger-Ellison syndrome, the only detectable gastrinoma was in the right liver lobe. Removal of the lobe, without additional gastric surgery, was followed by normalization of the gastrin level. Long-term follow-up confirmed the good result. The usefulness of quick intraoperative gastrin assay is stressed. 相似文献
5.
6.
A human myeloma immunoglobulin G binding four moles of calcium associated with asymptomatic hypercalcemia 总被引:3,自引:0,他引:3
Giampaolo Merlini Lorraine A. Fitzpatrick Ethel S. Siris John P. Bilezikian Steven Birken Sherman Beychok Elliott F. Osserman 《Journal of clinical immunology》1984,4(3):185-196
A calcium-binding immunoglobulin G (IgGIRUP) was identified in the serum of a patient with multiple myeloma, asymptomatic hypercalcemia, and a normal ionized serum calcium. Calcium binding by IgGRUP was confirmed by two-dimensional electrophoresis with calcium-45 and equilibrium dialysis. Amino acid analyses indicated an unusually high number of glutamic (or glutamine) residues in the L chain and Fab fragment but no detectable -carboxyglutamic acid. As determined by equilibrium dialysis with45Ca, the intact IgGRUP and its Fab fragments bound calcium at an optimum pH of 7.4. There was minimal binding of calcium to H chains and no binding by L chains or the Fc fragment. Recombination of H and L chains partially restored the binding activity. By Scatchard analysis, the binding affinity (K
d) of IgGRUP was 1.7×10–3
M and the binding capacity was 4 mol of calcium/mol of IgG. The binding of 4 mol of calcium/mol of IgG is twice that reported previously for two other calcium-binding myeloma proteins and suggests unique properties of IgGRUP. 相似文献
7.
Monti P Marchesi F Reni M Mercalli A Sordi V Zerbi A Balzano G Di Carlo V Allavena P Piemonti L 《Virchows Archiv : an international journal of pathology》2004,445(3):236-247
There are a large number of stable pancreatic ductal carcinoma cell lines (PDCL) that are used by researchers worldwide. Detailed data about their differentiation status and genetic alterations are present in the literature, but a systematic correlation with cell biological behavior is often lacking. PDCL (n=12) were clustered by source of tumor cell (ascites, primary tumor, metastasis), and the data of functional cell biology were correlated with the reported structural and genetic profiles. Major histocompatibility complex expression, chemosensitivity and aneuploidia appeared to be related to the source of PDCL, and proliferative capacity appeared to be related to the grade of differentiation. No correlation between genetic/structural features of PDCL and biological behavior was found. All the cell lines appeared generally insensitive to in vitro treatment with 5-fluorouracil and showed variable degrees of susceptibility to gemcitabine, raltitrexed and oxaliplatin. All the PDCL showed resistance to Fas-mediated apoptosis but were significantly sensitive to the pro-apoptotic effect of inflammatory cytokines [interleukin (IL)-1, tumor necrosis factor (TNF) and interferon ]. PDCL were characterized for the secretion of several factors relevant to the tumor-immune cross talk. Vascular endothelial growth factor, CCL2, CCL5 and transforming growth factor were the factors most frequently released; less frequent was the secretion of CXCL8, CCL22, IL-6 and sporadically CXCL12, IL-10 and hepatocyte growth factor. The cytokines IL-1 and TNF were always undetectable. In conclusion, a clear correlation between structural/genetic features and function could not be detected, suggesting the weakness of a morphological classification for the in vitro studies of pancreatic cancer. 相似文献
8.
Pathogenic role of P-selectin in experimental cerebral malaria: importance of the endothelial compartment
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Combes V Rosenkranz AR Redard M Pizzolato G Lepidi H Vestweber D Mayadas TN Grau GE 《The American journal of pathology》2004,164(3):781-786
P-selectin is a leukocyte adhesion receptor expressed on the surface of activated platelets and endothelial cells. Its role in the pathogenesis of cerebral malaria was explored in a murine model of cerebral malaria. Infection of mice with Plasmodium berghei ANKA led to P-selectin up-regulation in brain vessels of cerebral malaria-susceptible mice but not of cerebral malaria-resistant mice. Treatment of susceptible mice with anti-mouse P-selectin mAb failed to prevent the development of the neurological syndrome. However, P-selectin-deficient mice infected with Plasmodium berghei ANKA had a cumulative incidence of cerebral malaria which was significantly reduced compared to wild-type animals (4.5% versus 80%, respectively), despite identical levels of parasitemia, platelet and leukocyte accumulation. To determine whether P-selectin on platelets and/or endothelium was responsible for the microvascular pathology, cerebral malaria was assessed in chimeric mice deficient in platelet or endothelial P-selectin, which were generated by bone marrow transplantation. Mice deficient only in endothelial P-selectin did not show any sign of cerebral malaria (vascular plugging, hemorrhages, or edema), while mice lacking only platelet P-selectin showed signs of cerebral malaria similar to that seen in wild-type mice. These results indicate that endothelial P-selectin plays an important role in the pathogenesis of cerebral malaria. 相似文献
9.
Sarah L. Nolin Anne Glicksman Nicole Tortora Emily Allen James Macpherson Montserrat Mila Angela M. Vianna‐Morgante Stephanie L. Sherman Carl Dobkin Gary J. Latham Andrew G. Hadd 《American journal of medical genetics. Part A》2019,179(7):1148-1156
Instability of the FMR1 repeat, commonly observed in transmissions of premutation alleles (55–200 repeats), is influenced by the size of the repeat, its internal structure and the sex of the transmitting parent. We assessed these three factors in unstable transmissions of 14/3,335 normal (~5 to 44 repeats), 54/293 intermediate (45–54 repeats), and 1561/1,880 premutation alleles. While most unstable transmissions led to expansions, contractions to smaller repeats were observed in all size classes. For normal alleles, instability was more frequent in paternal transmissions and in alleles with long 3′ uninterrupted repeat lengths. For premutation alleles, contractions also occurred more often in paternal than maternal transmissions and the frequency of paternal contractions increased linearly with repeat size. All paternal premutation allele contractions were transmitted as premutation alleles, but maternal premutation allele contractions were transmitted as premutation, intermediate, or normal alleles. The eight losses of AGG interruptions in the FMR1 repeat occurred exclusively in contractions of maternal premutation alleles. We propose a refined model of FMR1 repeat progression from normal to premutation size and suggest that most normal alleles without AGG interruptions are derived from contractions of maternal premutation alleles. 相似文献
10.
Massimiliano Galdiero Mariateresa Vitiello Emma Sanzari Marina DIsanto Annalisa Tortora Anna Longanella Stefania Galdiero 《Infection and immunity》2002,70(2):558-568
In this study we examined the ability of Salmonella enterica serovar Typhimurium porins to activate activating protein 1 (AP-1) and nuclear factor kappaB (NF-kappaB) through the mitogen-activated protein kinase (MAPK) cascade, and we identified the AP-1-induced protein subunits. Our results demonstrate that these enzymes may participate in cell signaling pathways leading to AP-1 and NF-kappaB activation following porin stimulation of cells. Raf-1 was phosphorylated in response to the treatment of U937 cells with porins; moreover, the porin-mediated increase in Raf-1 phosphorylation is accompanied by the phosphorylation of MAPK kinase 1/2 (MEK1/2), p38, extracellular-signal-regulated kinase 1/2, and c-Jun N-terminal kinase. We used three different inhibitors of phosphorylation pathways: 2'-amino-3'-methoxyflavone (PD-098059), a selective inhibitor of MEK1 activator and the MAPK cascade; 4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)1H-imidazole (SB203580), a specific inhibitor of the p38 pathway; and 7beta-acetoxy-1alpha,6beta,9alpha-trihydroxy-8,13-epoxy-labd-14-en-11-one (forskolin), an inhibitor at the level of Raf-1 kinase. PD-098059 pretreatment of cells decreases AP-1 and NF-kappaB activation by lipopolysaccharide (LPS) but not by porins, and SB203580 pretreatment of cells decreases mainly AP-1 and NF-kappaB activation by porins; in contrast, forskolin pretreatment of cells does not affect AP-1 and NF-kappaB activation following either porin or LPS stimulation. Our data suggest that the p38 signaling pathway mainly regulates AP-1 and NF-kappaB activation in cells treated with S. enterica serovar Typhimurium porins. Antibody electrophoretic mobility shift assays showed that JunD and c-Fos binding is found in cells treated with porins, in cells treated with LPS, and in unstimulated cells. However, by 30 to 60 min of stimulation, a different complex including c-Jun appears in cells treated with porins or LPS, while the Fra-2 subunit is present only after porin stimulation. These data suggest different molecular mechanisms of activation induced by porins or by LPS. 相似文献