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排序方式: 共有1940条查询结果,搜索用时 15 毫秒
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F Sebastiano G Di Gennaro V Esposito A Picardi R Morace A Sparano A Mascia C Colonnese G Cantore P P Quarato 《Clinical neurophysiology》2006,117(2):341-347
OBJECTIVES: To evaluate a novel method for localization of subdural electrodes in presurgical assessment of patients with drug-resistant focal epilepsy. METHODS: We studied eight consecutive patients with posterior epilepsy in whom subdural electrodes were implanted for presurgical evaluation. Electrodes were detected on post-implantation brain CT scans through a semiautomated procedure based on a MATLAB routine. Then, post-implantation CT scans were fused with pre-implantation MRI to localize the electrodes in relation to the underlying cortical structures. The reliability of this procedure was tested by comparing 3D-rendered MR images of the electrodes with electrode position as determined by intraoperative digital photography. RESULTS: In each patient, all electrodes could be correctly localized and visualized in a stereotactic space, thus allowing optimal surgery planning. The agreement between the procedure-generated images and the digital photographs was good according to two independent raters. The mean mismatch between the 3D images and the photographs was 2 mm. CONCLUSIONS: While our findings need confirmation on larger samples including patients with anterior epilepsy, this procedure allowed to localize subdural electrodes and to establish the spatial relationship of each electrode to the underlying brain structure, either normal or damaged, on brain convessity, basal and medial cortex. SIGNIFICANCE: Being simple, rapid, unexpensive, and reliable, this procedure holds promise to be useful to optimize epilepsy surgery planning. 相似文献
3.
Carmine Zoccali Renke Maas Sebastiano Cutrupi Patrizia Pizzini Piero Finocchiaro Francesco Cambareri Vincenzo Panuccio Carmela Martorano Friedrich Schulze Giuseppe Enia Giovanni Tripepi Rainer Boger 《Nephrology, dialysis, transplantation》2007,22(3):801-806
BACKGROUND AND METHODS: The endogenous inhibitor of nitric oxide synthase (NOs) asymmetrical dimethyl-arginine (ADMA) has been implicated as a possible modulator of inducible NOs during acute inflammation. We examined the evolution in the plasma concentration of ADMA measured at the clinical outset of acute inflammation and after its resolution in a series of 17 patients with acute bacterial infections. RESULTS: During the acute phase of inflammation/infection, patients displayed very high levels of C-reactive protein (CRP), interleukin-6 (IL-6), procalcitonin and nitrotyrosine. Simultaneous plasma ADMA concentration was similar to that in healthy subjects while symmetric dimethyl-arginine (SDMA) levels were substantially increased and directly related with creatinine. When infection resolved, ADMA rose from 0.62 +/- 0.23 to 0.80 +/- 0.18 micromol/l (+29%, P = 0.01) while SDMA remained unmodified. ADMA changes were independent on concomitant risk factor changes and inversely related with baseline systolic and diastolic pressure. Changes in the ADMA/SDMA ratio were compatible with the hypothesis that inflammatory cytokines activate ADMA degradation. CONCLUSIONS: Resolution of acute inflammation is characterized by an increase in the plasma concentration of ADMA. The results imply that ADMA suppression may actually serve to stimulate NO synthesis or that in this situation plasma ADMA levels may not reflect the inhibitory potential of this methylarginine at the cellular level. 相似文献
4.
E Cianchetti R Cotellese A Dell'Osa M Nardi A D'Aulerio L Puglielli P Di Sebastiano C Saragani A M Napolitano 《Minerva chirurgica》1990,45(17):1093-1096
A case series of 5 male patients afflicted with breast carcinoma is reported. The Authors describe symptomatology, diagnostic iter, principles of surgical treatment and results. Underlined is the wider surgical demolition in male breast cancer in comparison with females, even if natural history and biological conduct are comparable. This is because in male breast carcinoma the local and remote infiltration is more rapid than female for the less development of breast gland. Finally, indications for radiochemotherapy are comparable to female breast cancer. 相似文献
5.
Alan A Arslan Anne Zeleniuch-Jacquotte Annekatrin Lukanova Yelena Afanasyeva Joseph Katz Mortimer Levitz Giuseppe Del Priore Paolo Toniolo 《Cancer epidemiology, biomarkers & prevention》2006,15(11):2123-2130
Epidemiologic evidence suggests that a full-term pregnancy may affect maternal risk of breast cancer later in life. The objective of this cross-sectional study was to compare circulating levels of maternal hormones affecting breast differentiation (human chorionic gonadotropin and prolactin) and proliferation [alpha-fetoprotein, insulin-like growth factor I (IGF-I), and estradiol] between women at a low to moderate risk (Asians and Hispanics), as compared with women at a high risk for breast cancer (Caucasians and African-Americans). Between May 2002 and December 2004, a total of 586 pregnant women were approached during a routine prenatal visit. Among them, 450 women (206 Caucasian, 126 Asian, 88 Hispanic, and 30 African-American) met the inclusion criteria and signed the informed consent. Only singleton pregnancies were considered. Blood samples were drawn during the second trimester of pregnancy. Laboratory analyses were done using the IMMULITE 2000 immunoassay system. Gestational age standardized mean levels of estradiol, IGF-I, and prolactin were significantly higher in Hispanic women compared with Caucasian women. Mean concentration of IGF-I was significantly higher in African-American women compared with Caucasian and Asian women. No significant differences in pregnancy hormone levels were observed between Caucasian and Asian (predominantly second-generation Chinese) women in this study. Irrespective of ethnicity, women who had their first pregnancy had substantially higher mean levels of alpha-fetoprotein, human chorionic gonadotropin, estradiol, and prolactin compared with women who previously had at least one full-term pregnancy. These data suggest that circulating pregnancy hormone levels may explain some of the ethnic differences in breast cancer risk. 相似文献
6.
Sister chromatid exchange (SCE) and lymphocyte proliferation were studied in peripheral lymphocyte cultures derived from 5 patients with Alzheimer disease (AD), 5 control elderly subjects and 5 young donors. These parameters did not differ significantly between the AD group and the elderly control group, but higher SCE frequency and less intensive proliferation were observed in the AD group and in the elderly control group when compared to the young donors. 相似文献
7.
Carlo Aprile Raffaella Saponaro Giuseppe Villa Mauro Carena Fabio Lunghi Sebastiano B. Solerte Alessandro Salvadeo 《European journal of nuclear medicine and molecular imaging》1986,12(1):37-40
The aim of this work is to correlate the net kidney uptake of99mTc-aprotinin (TcA) in 103 subjects with separate effective renal plasma flow (ERPF) and some blood chemistry parameters at 90, 180, and 360 min postinjection both in the normal and diseased kidney. Correlations found with separate ERPFs are highly significant at any time (P < 0.001). However, although the slope of the regression line is steeper at 180 min,r tends to deteriorate slightly with time postinjection and a higher intercept on they axis: this pattern is more pronounced if diseased kidneys are considered separately. The following are probably related to the renal handling of TcA: (1) Early scans better reflect blood flow to the kidney, while later scans are more related to the metabolism/excretion tubular mechanisms; (2) correlations found with urea, creatinine, urea clearance, and creatinine clearance are highly significant at any time; (3) in 20 additional patients with diseased kidneys, renal uptake measurements done 360 min postinjection first with TcA and then with DMSA showed better correlations with ERPF employing TcA. Our results indicate that TcA is a feasible indicator of split renal function even at 90 min postinjection when a scan is easily carried out on an outpatient basis.This paper was in part presented at the European Nuclear Medicine Congress, August 14–17, 1984, Helsinki, Finland 相似文献
8.
M H Kormann-Bortolotto M de A Smith J Toniolo Neto 《Mechanisms of ageing and development》1992,65(1):9-15
The fragile site expression under conditions of folate deprivation was compared in the chromosomes from 5 Alzheimer's disease (AD) female patients, 5 healthy elderly females and 5 healthy young females. Although different fragile sites were observed in the three groups, nevertheless, more similarities were found between the AD patients and elderly normal donors. The only fragile site common to all groups was 3p14. This site was the most frequent in the young donors group. In both AD and elderly control groups we observed a higher frequency of fragility in 6p21, but not in the young controls. Other interesting fragility points observed in these two groups were: 6q21 and 14q24 (in the AD patients) and 9q13, 14q24 and 17q21 (in the healthy aged). 6p21 and 17q21 have been proposed as 'new' fragile sites. We confirm the existence of these fragile sites and comment that in these bands the genes MTBT2 and MTBT1, which are microtubule (beta) associated protein tau-like and tau 1, respectively, are mapped. The tau protein is a component of paired helical filaments which accumulate in degenerating neurons in the brain of patients with AD and with less intensity of normal elderly individuals. 相似文献
9.
The tripeptide N alpha-carbamoyl-L-methionyl-L-leucyl-L-phenylalanine methyl ester has been synthesized in solution by classical methods and fully characterized. This compound, prepared in order to obtain a deeper insight into the mode of binding at the formyl peptide chemotactic receptor, has been tested for its ability to induce granule enzyme secretion from rabbit peritoneal neutrophils and found to be a complete agonist. These results confirm the hypothesis that a proton on the N alpha-blocking group of the tripeptide forms a hydrogen bond with an acceptor in the binding site. 相似文献
10.