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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
2.
Lung cancer is the leading cause of cancer deaths in both men and women in the United States. Treatment depends on the type and stage of lung cancer. For stage I and II cancer, surgery is usually the treatment of choice. Radiation therapy is used in patients who are considered poor risks for surgical resection. Intraoperative brachytherapy is an effective alternative to external irradiation in this group of patients. From 1958 to 1984, 55 patients with non-small-cell lung cancer were explored at Memorial Sloan Kettering Cancer Center and found to have surgical stage I or II tumors, which were considered to be unresectable mainly because of severe obstructive pulmonary disease precluding adequate resection. All these patients were treated with intraoperative brachytherapy at the time of the thoracotomy. Forty-four percent of these patients received in addition external irradiation, mainly to the mediastinum. The overall 5-year survival calculated by the Kaplan-Meier Method was 32%, and the local disease-free survival was 63%. Cox regression multivariant analysis demonstrated that there is a distinct subgroup with a better prognosis based on tumor site and patient's age--ie, patients who were younger than 58 years of age and had right-side lesions. 相似文献
3.
Summary Seventy-four cases of tuberculosis of the upper limb joints (sterno-clavicular 1; shoulder 12; elbow 42; wrist 10 and fingers 9), treated by two of the authors, were reviewed. Eighty-seven percent presented at an advanced stage of destruction. The diagnosis was proved in 71 out of 74 cases. In most, the treatment was 6–12 months of chemotherapy, plaster immobilization (in order to prevent or correct deformity) and functional rehabilitation whenever possible. The sterno-clavicular and finger joints were not immobilized. Response to chemotherapy was favourable in 66 of the patients followed up. One relapse occurred at the 18th month.The affected shoulder joints healed with loss of movement, but were not painful. At the elbow, ten patients developed spontaneous bony fusion in the right-angle position, 27 had a useful range of motion and 19 had more than 70° of flexion-extension movement. One patient had an arthrodesis. At the wrist, two patients healed with painful stiffness and an arthrodesis was performed. All the finger lesions healed with painless stiffness which did not interfere much with function because rehabilitation had been started early. The authors believe that conservative management usually gives better results than arthrodesis or excision of the joint.
Résumé Les auteurs rapportent les résultats de leur expérience dans 74 cas d'ostéo-arthrite tuberculeuse du membre supérieur: 1 sterno-claviculaire, 12 scapulo-humérales, 42 coudes, 10 poignets et 9 articulations des doigts, toutes traitées personnellement par les deux auteurs principaux. Sur le plan diagnostique, 87% des patients se présentaient à un stade de destruction avancée. Le diagnostic de certitude fut obtenu dans 71 cas sur 74. Dans la majorité des cas, le traitement a été standardisé: chimiothérapie de 6 à 12 mois, immobilisation plâtrée pour prévenir ou corriger les déformations, suivie de reéducation chaque fois que possible. Les lésions de la sterno-claviculaire et des doigts ne furent pas immobilisées. Les résultats ont été bons en ce qui concerne la chimiothérapie: 66 réponses favorables chez 66 patients suivis. Il y a eu une rechute au 18éme mois. Du point de vue orthopédique, les lésions scapulo-humérales ont guéri avec une raideur de l'épaule toujours importante mais indolore. Au niveau du coude, 10 patients évoluèrent vers la fusion osseuse précoce spontanée, qui se fit à 90° de flexion grâce à l'immobilisation plâtrée; 27 guérirent avec une conservation variable des mouvements du coude dans un secteur fonctionnel et 19 d'entre eux présentaient plus de 70° d'étendue de flexion; 1 patient fut arthrodésé. Au niveau du poignet, 2 patients guérirent avec une raideur douloureuse qui nécessita une arthrodèse. Les lésions des doigts guérirent avec une raideur plus ou moins marquée, bien compensée par la mobilité des autres articulations, conservée intacte par la reéducation. Les auteurs concluent à la meilleure qualité des résultats du traitement conservateur que des classiques interventions d'arthrodèse ou de résection articulaire.相似文献
4.
5.
Fernanda Martini Alfredo Corallini Veronica Balatti Silvia Sabbioni Cecilia Pancaldi Mauro Tognon 《Infectious agents and cancer》2007,2(1):13-12
Simian virus 40 (SV40) is a monkey virus that was administered to human populations by contaminated vaccines which were produced
in SV40 naturally infected monkey cells. 相似文献
6.
Testicular biopsy specimens from infertile men (sperm count, less than 10(6)/ml) were evaluated on 1-micron thick sections, and counts of stem cells and differentiated spermatogonia, primary spermatocytes, early and late spermatids, and Sertoli cells were compared to counts in six fertile men. Biopsy specimens were also compared for the appearance of seminiferous tubule wall, blood vessels, and interstitium. Infertile men were grouped according to the following diagnoses: hypospermatogenesis (n = 5), spermatocyte arrest of spermatogenesis (n = 5), and obstruction of the genital tract (n = 7). A low productivity of spermatogenesis in cases of hypospermatogenesis appeared to be due to an exaggerated degeneration of primary spermatocytes and to a yield of abnormal spermatids. A block of meiosis in spermatocyte arrest was associated with a degeneration of primary spermatocytes and with a reduced number of staminal spermatogonia. Abnormal spermiogenesis was observed in cases of obstruction of the genital tract and was associated with an increase in stem cell spermatogonia. A thickening of seminiferous tubule and blood vessel walls could be responsible for the limited functional capacity of Sertoli cells, causing altered spermiogenesis in cases of excretory azoospermia. A severe primitive failure of Sertoli cells in secretory oligoazoospermia could account for a deranged maturation and degeneration of premeiotic and postmeiotic germ cells. 相似文献
7.
Luigi La Vecchia Paolo Vincenzi Luca Favero Manuela Martini Andrea Rubboli Filippo Ottani Leonardo Varotto Alessandro Fontanelli 《Italian heart journal》2004,5(10):749-754
BACKGROUND: Recent studies evaluated the technique of direct coronary stenting as compared to stenting-after-predilation in selected anatomic and clinical settings. However, the impact of direct stenting in routine interventional practice remains poorly elucidated. METHODS: From April 1999 to March 2001, all percutaneous coronary interventions performed at our Center were prospectively analyzed to determine the frequency of direct stenting, the success rate and the variables associated with its utilization. RESULTS: 1151 lesions were treated in 835 procedures. Stenting was attempted in 835/1151 lesions (72.5%), 309 (37%) with direct stenting and 526 (63%) with stenting-after-predilation. Direct stenting was successful in 300/309 (97%) and stenting-after-predilation in 515/526 (98%). The success rate of direct stenting was significantly lower in small vessels (< or = 2.75 mm) (89.2 vs 98.5%, p = 0.005). Patients treated with direct stenting were younger (63 +/- 11 vs 65 +/- 11 years, p = 0.024). Direct stenting was preferentially used in saphenous vein grafts and at the ostium of the left anterior descending coronary artery, while it was avoided in bifurcation lesions and with increasing calcium burden. Operators with a caseload > 140 interventions per year were significantly more likely to perform direct stenting than less experienced operators (p = 0.017). In direct stenting, the total contrast medium and the fluoroscopy and procedural times were all significantly (p < 0.0001) lower than those observed in case of stenting-after-predilation. CONCLUSIONS: Direct coronary stenting is currently performed in about one third of the overall caseload. Variables pertaining to the operator's experience, lesion morphology and length, vessel size, and the clinical presentation are all important factors determining the selection of candidates suitable for direct stenting. 相似文献
8.
9.
G Biagi O Livi A Lucacchini C Martini V Scartoni 《Journal of pharmaceutical sciences》1992,81(6):543-545
Certain 1,2,3-triazole derivatives were prepared and tested for their ability to displace [3H]diazepam that was bound to bovine brain membrane protein. All the tested compounds are essentially lacking in this ability, except for B.1, which inhibited binding of [3H]diazepam in 50% of the trials at 2.5 microM. The structure of B.1, with a 1,2,3-triazole ring with acidic properties, supports the hypothesis proposed for binding to the benzodiazepine receptor site. Comparison of B.1 with 1,2,3-triazole derivatives bearing a bicyclic substituent in position 1 of the heterocyclic ring suggests that a high steric hindrance increases the affinity of a compound for the benzodiazepine receptor. 相似文献
10.