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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
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Characterization of gp 50, a major glycoprotein present in rat brain synaptic membranes, with a monoclonal antibody 总被引:4,自引:0,他引:4
Philip W. Beesley Toni Paladino Claude Gravel Richard A. Hawkes James W. Gurd 《Brain research》1987,408(1-2):65-78
Several cell lines secreting monoclonal antibodies (Mabs) against a major forebrain synaptic membrane (SM) glycoprotein, gp 50, have been raised. Western blots show that the Mabs react with a polypeptide doublet of Mrs 49 and 45 kDa. These polypeptides exist solely in a concanavalin A (Con A) binding form. Removal of the Con A receptors by digestion with endo-beta-N-acetylglucosaminidase H (endo H) lowers the Mrs of the glycoprotein doublet to 36.5 and 34 kDa. Western blots of 2D polyacrylamide gels indicate that gp 50 exists in several isoforms. Solid phase radioimmunoassay (RIA) and Western blots of brain subcellular fractions show the antigenic material to be concentrated in the SM fraction, but to be present in much lower amounts in synaptic junctions and postsynaptic densities. Gp 50 appears to be brain specific. Regional distribution studies show that it is present in all brain regions but is two-fold concentrated in cerebellum, brainstem and midbrain compared to forebrain. Immunocytochemical studies of several brain regions show that gp 50-like immunoreactivity is neuron specific and is concentrated in selected neuronal species, particularly granule cells. In both cerebellar and hippocampal granule cells gp 50-like immunoreactivity is localized in the perikarya and primary dendrites. Though immunocytochemistry did not show staining of synaptic regions this may be due to masking of the reactive epitope. The results are discussed in terms of the molecular properties of gp 50 and its subcellular localization in brain tissue. 相似文献
4.
Dr. Joseph A. Paladino Pharm.D. Dr. Miguel A. Rainstein M.D. FACS Mrs. Deborah J. Serrianne R.N. Dr. John E. Przylucki M.D. FACS Dr. Lynda S. Welage Pharm.D. Dr. Mario L. Collura M.D. FACS Dr. Jerome J. Schentag Pharm.D. FCCP 《Pharmacotherapy》1994,14(6):734-739
This double-blind study compared ampicillin-sulbactam 3 g versus cefoxitin 2 g in 136 adult patients at risk for developing an infection after abdominal surgery. Separate randomization schedules were used for colorectal, upper gastrointestinal/biliary, and other abdominal procedures. Study antibiotics were administered within 30 minutes before incision and repeated 6 hours later. Patients having colorectal surgery received a third dose of antibiotic 6 hours after the second. Efficacy evaluations were made on 123 patients, 62 in the ampicillin-sulbactam group and 61 in the cefoxitin group. The overall postoperative infection rates were 12.9% for ampicillin-sulbactam and 9.8% for cefoxitin (p>0.05); one wound infection occurred in each group. Adverse events were experienced by 13.2% of the ampicillin-sulbactam and 19.1% of the cefoxitin recipients (p>0.05). Cost-minimization analysis revealed that ampicillin-sulbactam was a cost-effective alternative to cefoxitin for the prevention of infection after abdominal surgery. 相似文献
5.
Cinzia Bressi Cesare Maria Cornaggia Massimiliano Beghi Matteo Porcellana Ilaria Ida Iandoli Giordano Invernizzi 《Seizure》2007,16(5):417-423
PURPOSE: To verify the emotional components expressed by the relatives of adult patients with a diagnosis of epilepsy, and whether they are related to adjustment to the illness and the course of the illness over time. METHODS: We studied a consecutive sample of 43 outpatients suffering from epilepsy and 43 key relatives using the Camberwell Family Interview (CFI), with the expressed emotion (EE) of the relatives being rated at baseline (T0). EE refers to a construct representing some key aspects of interpersonal relationships: the relatives were assigned to the high-EE group if they scored 3 or more on the emotional over involvement (EOI) scale, or showed hostility, or made 6 or more critical comments. The patients were clinically evaluated at baseline and for 1 year of appropriate treatment by an epileptologist who was blinded to the EE ratings. They also completed STAI XI, STAI X2 and Beck's Depression Inventory at baseline. RESULTS: Twenty-six relatives (60%) were rated as showing a high degree of EE. In the 12-month follow-up study, high EE and high EOI were found to be associated with a significantly higher seizure frequency than that recorded for the patients living in low-EE households (p<0.05). The patients from households assessed as reflecting a high degree of criticism showed poor drug compliance (p<0.01), whereas those with relatives assessed as having a high degree of warmth showed better clinical and pharmacological compliance (p<0.01). High family criticism scores also correlated with higher study entry levels of depression (p<0.05) and trait and state anxiety (p<0.05) among the patients. CONCLUSIONS: The study findings highlight the impact of particular components of the family emotional climate on the clinical course and psychological adjustment of patients with epilepsy. 相似文献
6.
Cinzia Azzoni Tiziana D’Adda Guido Tamburrano Carlo Coscelli Ole D. Madsen Lucio Scopsi C. Bordi 《Virchows Archiv : an international journal of pathology》1998,433(6):495-504
Sixty-seven insulinomas were investigated by immunohistochemistry using site-directed antibodies against insulin, proinsulin, chromogranin A, HISL-19, and four proteins directly or indirectly involved in the proteolytic processing of proinsulin: the prohormone convertases PC2 and PC3, carboxypeptidase H (CPH) and 7B2. Results were expressed in a six-grade score according to the frequency of immunoreactive tumour cells. Insulin was expressed by all tumours, appearing in either a diffuse or a polarized pattern and being detected in more than 30% of tumour cells in all cases but three. Proinsulin was also expressed in all tumours, with more than 50% of tumour cells immunoreactive in all cases but 5. It was consistently localized in the Golgi apparatus. In about half the cases, moreover, it also showed diffuse cytoplasmic staining, usually with a very sparse distribution. Trabecular and solid insulinomas did not present specific, homogeneous patterns of insulin immunostaining. However, insulin immunoreactivity was much more abundant in trabecular than in solid neoplasms, being present in virtually all tumour cells (score 6) in 50% and 8% of cases, respectively. Virtually all insulinomas expressed PC2, PC3, CPH and 7B2, usually in 30–100% of tumour cells, with a frequency significantly related to that of insulin. However, detection of PC2 and 7B2 was slightly less frequent than that of PC3 and CPH. In consecutive sections these proteins were found to be mostly co-localized with insulin and chromogranin A but not with proinsulin. They were heavily expressed in all 10 tumours with more than 10% of cells showing cytoplasmic proinsulin immunoreactivity, indicating that the leakage of proinsulin from the Golgi compartment is not associated with faulty expression of converting enzymes and possibly reflects a saturated processing capacity. HISL-19 immunoreactivity was found in both Golgi apparatus and insulin stores, indicating that the relevant antigen is different from all other proteins investigated. These results do not support a defect in expression or localization of proinsulin-processing enzymes in most insulinomas. 相似文献
7.
D'adda T Pizzi S Azzoni C Bottarelli L Crafa P Pasquali C Davoli C Corleto VD Delle Fave G Bordi C 《Human pathology》2002,33(3):322-329
Most foregut digestive endocrine neoplasms may be associated with the multiple endocrine type 1 (MEN-1) syndrome. In contrast, midgut/hindgut carcinoids never show such association. To investigate the pathogenetic involvement of the MEN-1 gene and of putative additional oncosuppressor gene(s) distal to it, a comparative analysis of loss of heterozygosity (LOH) at chromosome 11q13 to 11qter was performed in 27 foregut (pancreatic endocrine tumors [PETs]), 23 midgut (ileal and appendiceal), and 3 hindgut (rectal) endocrine tumors. LOH at the MEN-1 gene locus at 11q13 was observed in 52% of the 23 sporadic and in all 4 MEN-1-associated PETs and was found to consistently and continuously span to the most distal marker investigated at 11qter. In contrast, only occasional, discontinuous, and mostly interstitial LOH for 11q markers was observed in ileal (midgut) carcinoids, whereas no LOH was found in all appendiceal (midgut) and rectal (hindgut) carcinoids. The consistent extension of LOH from the MEN-1 region to 11qter in sporadic PETs suggests a mechanism of gene inactivation via chromosomal breakage and complete loss of chromosome 11q; furthermore, these results expand beyond the 11q13 region the search for additional oncosuppressor gene(s) potentially involved in the genesis of these neoplasms. The low frequency, limited extension, and discontinuous distribution of 11q deletions in midgut/hindgut carcinoids suggest that MEN-1 gene is not involved in the pathogenesis of these tumors. 相似文献
8.
9.
Bianchi F Mattii L D'Alessandro D Moscato S Segnani C Dolfi A Bernardini N 《Acta histochemica》2003,105(1):89-97
Rho proteins, a subgroup of the Ras GTPase superfamily, control many cellular processes and morphogenetic events by acting as signaling molecules in the transduction pathways of various receptors. Among the "Rho-dependent" receptors are the extracellular matrix- and growth factor-binding sites; these are particularly involved in the modulation of renal development since they control the epithelial-mesenchymal interactions that drive kidney organogenesis. The present study has addressed the immunohistochemical localization of RhoA in developing and adult kidneys of rats and humans because: a) Rho proteins are known to have a morphogenetic role, b) data in the literature on expression of Rho GTPases during mammalian histogenesis and organogenesis are scarce, and c) their involvement in the transduction pathways of receptors is implicated in kidney development. In particular, RhoA peptide was found to be localized in the mesonephric duct and vesicles in both rats and humans; metanephric anlagen were mainly stained in ampullar-derived cells. Periglomerular tubules of fetal and adult kidneys as well as collecting ducts of adult kidneys showed intense staining. Therefore, the present study provides new information on the distribution patterns of RhoA during early stages of mammalian kidney development suggesting that this signaling molecule may take part in epithelial-mesenchymal induction processes that control kidney organogenesis. RhoA expression in adult structures may be linked with renewal of renal epithelial cells and the maintenance of their morphology and polarity. 相似文献
10.
A MicroRNA signature associated with prognosis and progression in chronic lymphocytic leukemia 总被引:2,自引:0,他引:2