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A study of DNA content by flow cytometry revealed a significant difference between rhabdomyosarcomas, which were mainly non-diploid, and other sarcomas of children which were mainly diploid (p = 0.01). There was no association between DNA ploidy and survival or aggressive behaviour of the tumour as indicated for example by advanced clinical stage or unfavourable histology. While DNA ploidy correlated with age, it did not correlate with any other clinical characteristic. The apparent lack of prognostic value of DNA content may have been masked by some high CV values and overridden by the effect of chemotherapy which was the most significant variable in determining a patient's survival (p = 0.00005). 相似文献
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A new model of embolic stroke produced by photochemical injury to the carotid artery in the rat 总被引:2,自引:0,他引:2
N Futrell B D Watson W D Dietrich R Prado C Millikan M D Ginsberg 《Annals of neurology》1988,23(3):251-257
We report a new model of embolic stroke in the rat, based on endothelial disruption and platelet aggregation in the carotid artery, which leads to distal embolization and focal brain infarction. The common carotid artery was irradiated for 6.5 minutes with the focused beam of an argon laser operated at a wavelength of 514.5 nm with a peak power of 2 W and an average power of 400 mw. Ipsilateral cerebral infarcts, ranging in size from 0.1 to 1.7 mm, were produced by platelet emboli in 12 of 13 rats. A total of 44 infarcts were observed in the 12 rats: 29 in the cortex, 6 in the hippocampus, 5 in the thalamus, and 4 in the basal ganglia. Scanning electron microscopy identified platelet aggregates in the carotid artery and in a deep cortical arteriole 50 minutes after the photochemical lesion. Twenty-four hours after the experiment, scanning electron microscopy of the carotid artery revealed damaged endothelium but few remaining adherent platelets. More intense laser irradiation in 8 rats, leading to carotid occlusion, produced an infarct in only 1. This new model can be used to study the acute and chronic pathological changes in the brain associated with platelet embolism. 相似文献
37.
M Guerrero Fernández J L Alfonso Sánchez B Sanchís Noguera M J Prado del Ba?o 《Gaceta sanitaria / S.E.S.P.A.S》1992,6(29):62-66
Data are presented on hospital stay for the population 65 years-old and over, measured in percentage over the total for Spain, for the 1978 to 1988 period, by gender, for each province and autonomous region (Comunidad Autónoma). The country's total for the last available year was 35%. Except in Baleares and Murcia, the proportion of hospital stays increased in all Regions, especially in Navarra, where it increased from 23% to 51%. After adjusting for age, the increase in the proportion of hospital stays in the study population was due to an increase in utilization per person. The proportion, which was 13.3% in 1978, raised to 23.8% in 1988, with an adjusted value of 21.3%. 相似文献
38.
Luciana Dias de Oliveira Elsa Regina Justo Giugliani Lílian Córdova do Espírito Santo Maristela Cavalheiro Tamborindeguy Fran?a Enilda Maria Lara Weigert Celina Valderez Feijó Kohler Ana Lúcia de Lourenzi Bonilha 《Journal of human lactation》2006,22(3):315-321
This randomized clinical trial compared frequencies of exclusive breastfeeding and lactation-related problems during the first 30 days among 74 mothers who received a 30-minute counseling session on breastfeeding technique in the maternity ward, and 137 controls. The frequency of exclusive breastfeeding among mothers who had received intervention was similar to controls by 7 days (79.7% vs 82.5%, respectively) and 30 days (60.8% vs 53.3%). There was no difference between groups in the frequency of sore nipples at 7 and 30 days, in breast engorgement and mastitis, and in the quality of breastfeeding technique at 30 days. Therefore, a single intervention at maternity was not sufficient to improve breastfeeding technique, increase exclusive breastfeeding rates, and reduce the incidence of breastfeeding problems during the first month. 相似文献
39.
Dione Dias Torriani Célio Percinoto Robson Frederico Cunha Íria Guimarães 《Dental traumatology》2006,22(4):198-204
Abstract – The aims of this study were to analyze the histomorphology of developing permanent teeth whose primary teeth had suffered traumatic intrusion, as well as to compare the influence of immediate extraction of the intruded tooth to passive re-eruption. Nine dogs from 45 to 50 days old were submitted to the intrusion of the maxillary central and lateral primary incisors using a force applicator adapted to the teeth incisal cuspids. The right side intruded teeth were kept in their sockets and the ones on the left side were extracted 30 min later. After a postoperatory periods of 30 and 60 days, four (group 1) and five (group 2) dogs, respectively, were killed by perfusion. The histological evaluations showed that, in group 1, alterations had occurred in the odontoblastic layer and deposition of the enamel matrix had taken place in some specimens while in group 2, a portion of non-mineralized matrix was observed. We concluded that the morphological changes were because of the immediate trauma of intrusion. No differences were found between the groups where the primary tooth was immediately extracted or left to passively re-erupt. 相似文献
40.
Michelle Lucinda DeOliveira M.D. Tarcisio Triviño M.D. Ph.D. Gaspar de Jesus Lopes Filho M.D. Ph.D. 《Journal of gastrointestinal surgery》2006,10(8):1140-1143
Carcinoma of the papilla of Vater is classified as periampullary cancer representing 5% of all gastrointestinal tract malignancies.
Early and accurate diagnosis is important for those patients with a tumor of the papilla, as the prognosis is more favorable
than in other periampullary neoplasms. Endoscopically obtained biopsies from suspicious papillae can detect an early tumor,
although even for skilled pathologists it is often difficult to differentiate carcinomas from noninvasive lesions on the basis
of forceps biopsies. The purpose of this study was to assess the preoperative diagnostic accuracy of duodenoscopy appearance
and biopsy in all cases with suspicion of tumor. Thirty patients with suspicion of carcinoma of the papilla of Vater and with
final diagnosis established by pancreatoduodenectomy were included in this retrospective study. In each case, a comparison
was made between endoscopic biopsy and duodenoscopic appearance. Duodenoscopic appearance sensitivity and accuracy for malignancy
were 86% and 83%, respectively, whereas endoscopic biopsy sensitivity and accuracy were 65% and 67%, respectively. Although
preoperative diagnosis of carcinoma of the papilla of Vater is useful for making therapeutic decisions, the diagnostic value
of the endoscopic appearance was superior to endoscopic biopsy in this series.
Presented at the 2003 American Hepato-Pancreato-Biliary Association Congress, Miami, Florida, February 27-March 3, 2003.
Supported by FADA-CAPES/PROP 200J (M.L.D.). 相似文献