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61.
P S Buonuomo A Ruggiero G Zampino P Maurizi G Attinà R Riccardi 《Journal of perinatology》2006,26(10):653-655
Pathological fractures occur in infancy from a variety of causes, but are a rare condition during neonatal period. We describe the case of a male newborn with a metaphyseal fracture of femur and multiple lytic lesions, diagnosed as infantile myofibromatosis. 相似文献
62.
Romaric Audigier Roberto Lotufo Alexandre Falc?o 《Computerized medical imaging and graphics》2006,30(4):217-230
In medical imaging, many applications require visualization and/or analysis of three-dimensional (3D) objects (e.g. organs). At same time, object definition often requires considerable user assistance. In this process, objects are usually defined in an iterative way and their visualization during the process is very important to guide the user's actions for the next iteration. The usual procedure provides slice visualization during object definition (segmentation) and 3D visualization afterward. In this paper, we propose and evaluate efficient methods to provide 3D visualization during iterative object definition. The methods combine the differential image foresting transform for segmentation with voxel splatting/ray casting for visualization. 相似文献
63.
Roberto Rivera-Luna Marta Zapata-Tarrés Aurora Medina-Sansón Enrique López-Aguilar Ana Niembro-Zúñiga J. Amador Zarco Alfonso Marhx-Bracho Fernando Rueda-Franco Leticia Bornstein-Quevedo 《Child's nervous system》2007,23(5):543-547
Objective The purpose of this study is to analyze clinical aspects and disease-free survival (DFS) in children less than 3 years of
age diagnosed with low-grade astrocytoma.
Methods In a period of 24 years (1980–2004), a total of 43 (5.4%) children were registered with these characteristics. Twenty-three
patients had pilocytic astrocytoma, 18 diffused, and 2 mixed. Thirty-one (72.1%) children had incomplete surgical tumor resection
and 12 (27.9%) had a complete tumor resection. Twelve (27.9%) patients had cranial radiotherapy and 17 (39.5%) received chemotherapy.
Overall survival was recorded in 23 (53%). DFS was 50% at 250 months of follow-up for the whole group. DFS for the supratentorial
group was 60% at 250 months, whereas, for the infratentorial, it was 22% at 120 months (p = 0.008).
Conclusion The only favorable prognostic pattern was the supratentorial presentation. Radiotherapy and chemotherapy did not alter the
outcome. 相似文献
64.
Linda Wang D.D.S. M.S. Ph.D. Lawrence Gonzaga Lopes D.D.S. M.S. Ph.D. Eduardo Bresciani D.D.S. M.S. José Roberto Pereira Lauris D.D.S. M.S. Ph.D. Rafael Francisco Lia Mondelli D.D.S. M.S. Ph.D. Maria Fidela de Lima Navarro D.D.S. Ph.D. 《Special care in dentistry》2004,24(1):28-33
Atraumetic Restorative Treatment (ART) has been adopted around the world to avoid unnecessary extractions, especially in non-industrialized countries The development of specific glass ionomer cements marketed for the ART technique has contributed to the technical success rate. In this study. Ketac-Molara (3M ESPE. Dental Medzn Germany) was used to restore 150 Class I cavities in 118 Brazilian public school children, aged from 7–12 years. At baseline and at subsequent recalls. CPI probes with a ball-end of 0.5 millimeters (mm) were used to assess loss of restorative material, and photographic color transparencies of restorations were made. After six months. 83 patients returned for follow-up examinations, with 71.8% of their restorations designated as acceptable. After three years. 49 patients with 57 ART-restorations were evaluated, with 21.0% of these restorations graded as acceptable Another 29.8% of their restorations had been replaced by more permanent materials. The main objective of the ART technique is tooth retention; this was achieved for 94.7% of the restored teeth in a high caries risk population who returned for recalls. 相似文献
65.
Gianluigi Tanda Francesco E. Pontieri Roberto Frau Gaetano Di Chiara 《The European journal of neuroscience》1997,9(10):2077-2085
This study was performed to investigate the relative role of noradrenaline (NA) and dopamine (DA) carrier blockade in the effects of psychostimulants on DA transmission in the rat prefrontal cortex (PFCX). To this end, changes of extracellular DA and NA in the PFCX and of extracellular DA in the nucleus accumbens (NAc) were measured following the administration of amphetamine and cocaine, which are known to bind to both DA and NA carriers, or GBR 12909, a selective DA carrier blocker. After non-intravenous injection, amphetamine (0.25 and 0.5 mg/kg, s.c.) and cocaine (5 and 10 mg/kg, i.p.) increased extracellular DA in the PFCX to a larger extent than in the NAc, while the reverse applied to GBR 12909 (2.5 and 5 mg/kg, i.p.). These differences were obtained in spite of the fact that the three drugs elicited at each dose level a similar peak increase of extracellular DA in the NAc. Amphetamine and cocaine also increased extracellular NA in the PFCX and this effect was quantitatively similar to that on extracellular DA in the same area. Intravenous doses of cocaine and GBR 12909, corresponding to those which maintain self-administration in the rat, while equieffective in raising extracellular DA in the NAG, had different effects on extracellular DA in the PFCX. In fact, in contrast to cocaine, GBR 12909 increased extracellular DA in the PFCX to a lesser extent than in the NAc or did not modify it at all. The peak increase of extracellular DA in the PFCX was highly correlated to that of NA in the same area but was poorly correlated to the increase of extracellular DA in the NAc. These results suggest that amphetamine and cocaine increase extracellular DA in the PFCX largely through the blockade of the NA carrier. Direct evidence for this hypothesis was provided by the observation that, when the NA carrier was blocked by reverse dialysis of the PFCX with desipramine (1 μM), cocaine and GBR 12909 lost their differences in the ability to increase extracellular DA in the PFCX. 相似文献
66.
67.
Claude Clément MD Roberto Ruiz MD Bogdan Costa-Foru MD Hubert Nicaise MD 《Annals of vascular surgery》1990,4(3):305-308
Extrinsic compression of the renal artery due to a fibromuscular band originating from the diaphragm was encountered in a 26-year-old patient who had systemic hypertension associated with stenosis and kinking of one of her renal arteries. After surgical decompression, the renal artery assumed a normal expansion with disappearance of hypertension. Six other cases of extrinsic compression of the renal artery have been found in the literature. Surgical treatment is mandatory in all cases because the mechanism that causes the lesion makes percutaneous transluminal angioplasty illusory. 相似文献
68.
G Ucci M Petrini A Riccardi R Invernizzi G Carulli R Luoni M Giordano M Danova 《Hematological oncology》1992,10(3-4):213-220
The expression of the p170 multidrug resistance protein by bone marrow plasma cells (BMPC) was assessed at clinical presentation in 53 patients with multiple myeloma (MM) using the C219 monoclonal antibody. Twenty-two of the 53 (41 per cent) patients had variable aliquots (1-60 per cent, median = 6 per cent) of p170+ BMPC by immunocytochemistry. Five of 10 patients studied using bivariate flow cytometry had both diploid and hyperdiploid (DNA index ranged from 1.2 to 1.5) BMPC with hyperdiploid clones having significantly greater p170 expression than diploid ones. Of the 37 patients evaluated for a response, 20 (54 per cent) had responded to induction chemotherapy. The presence of p170+ BMPC was a negative indicator for achieving response. The response rate was 75 per cent for p170- and 25 per cent for p170+ cases (p < 0.01), with no difference on the basis of treatment schedule (melphalan and prednisone, 24 patients; peptichemio, vincristine and prednisone, 13 patients). No difference in response and survival duration was found between p170+ and p170- patients. In six of nine patients studied both at diagnosis and following induction chemotherapy the p170+ BMPC% increased irrespective of the type of treatment or outcome. 相似文献
69.
Mono- and bi-allelic expression of insulin-like growth factor II gene in human muscle tumors 总被引:4,自引:1,他引:3
Pedone Paolo V.; Tirabosco Roberto; Cavazzana Andrea O.; Ungaro Paola; Basso Giuseppe; Luksch Roberto; Carli Modesto; Bruni Carmelo B.; Frunzio Rodolfo; Riccio Andrea 《Human molecular genetics》1994,3(7):1117-1121
Insulin-like growth factor II (IGF-II) is a mitogen for manycell types and an important modulator of muscle growth and differentiation.IGF-II gene is prevalently expressed during prenatal developmentand its gene activity is regulated by genomic imprinting, inthat the allele inherited from the father is active and theallele inherited from the mother is inactive in most normaltissues. IGF-II expression is activated in several types ofhuman neoplasms and an alteration of IGF-II imprinting has beendescribed in BeckwithWiedemann syndrome and Wilms' tumour.Here we show that monoallelic expression of IGF-II gene is conservedin normal adult muscle tissue whereas two or more copies ofactive IGF-II alleles, arising by either relaxation of imprintingor duplication of the active allele, are found in 9 out of 11(82%) rhabdomyo-sarcomas retaining heterozygosity at 11p15,regardless of the histological subtype. Since IGF-II has beenindicated as an autocrine growth factor for rhabdomyosarcomacells, these findings strongly suggest that acquisition of adouble dosage of active IGF-II gene is an important step forthe initiation or progression of rhabdomyosarcoma tumorigenesis.Among different types of muscle tumors, relaxation of imprintingseems to arise prevalently in rhabdomyosarcomas, since we havedetected only one case of partial reactivation of the maternalIGF-II allele out of 7 lelomyosarcomas tested. 相似文献
70.
L Troncone R Riccardi P Montemaggi V Rufini A Lasorella R Mastrangelo 《Medical and pediatric oncology》1987,15(4):220-223
Seven patients with neuroblastoma (six children and one adult) were treated with therapeutic doses of high specific activity 131I-metaiodobenzylguanidine (131I-MIBG). Six patients were in stage IV and unresponsive to conventional treatment. One patient, in stage III, was treated at diagnosis, an approach never previously reported. Single doses of 131I-MIBG varying from 70 to 184 mCi split into two parts were administered by slow i.v. infusion (4 to 8 hours) at 2- to 4-day intervals. The following results were obtained in the six evaluable patients: two patients showed transient stabilization of the disease; three had an objective response, with shrinking of the primary tumor and/or regression of the metastatic lesions. Of these three patients, two suffered relapses at 2 and 7 months, respectively, from the first course of MIBG. The third patient, in whom the residual disease almost completely disappeared following MIBG therapy, is still alive in complete remission after autologous bone marrow transplantation with a follow-up of 14 months. The single patient treated at diagnosis showed a dramatic response to a relatively low dosage of MIBG, with histologically proved disappearance of the tumor mass. Our data indicate that MIBG may be useful in the treatment of neuroblastoma unresponsive to conventional chemotherapy. The complete response observed in the patient treated at diagnosis suggests that the full potentiality of MIBG therapy should be explored in untreated patients. 相似文献