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排序方式: 共有943条查询结果,搜索用时 15 毫秒
1.
Enrico Verrina Barbara Andreetta Sergio Bassi Roberto Bonaudo Domenica A. Caringella Alfonso Castellani Pierluigi Cavalli Alberto Edefonti Giancarlo Lavoratti Luigi Longo Ivana Pela Rosa Penza Francesco Perfumo Virgilio Petrucci Marina Picca Mauro Ragaiolo Stefano Rinaldi Gianfranco Rizzoni Palma Sorino Giusto Viglino Graziella Zacchello Rosanna Gusmano 《Pediatric nephrology (Berlin, Germany)》1992,6(1):78-81
The results of the first 3 year' collaboration of the Italian Registry of Paediatric Chronic Peritoneal Dialysis (CPD) (1986–1988) are presented. This Registry acquired data on the majority of the paediatric patients treated with CPD in Italy, thus providing a national picture in a field where few nationwide surveys are available. Patients of less than 15 years of age at the start of dialysis were enrolled and clinical data collected until the age of 19 years. The number of nephrological paediatric centres participating in the Registry increased from 7 in 1986 to 11 in 1988. The total number of patients on CPD was 70 and the percentage of dialysed children treated with CPD ranged from 40.2% to 43.6%. Data on 89 peritoneal catheters were collected: during 1417 dialysis-months 70 catheter-related complications were observed (1:20.8 dialysis-months); actuarial catheter survival was 92.7% at 6 months, 84.8% at 1 year and 68.8% at 2 years. The incidence of peritonitis changed from 1 episode every 10.9 patient-months in 1986 to 1 every 19.8 in 1988. Abdominal hernias were the other main clinical complication observed. The survival of patients was 92.5% at 3 years, while the technique survival at the same time was 84%. 相似文献
2.
Angiogenic response induced by acellular aortic matrix in vivo 总被引:2,自引:0,他引:2
Conconi MT Nico B Mangieri D Tommasini M di Liddo R Parnigotto PP Nussdorfer GG Ribatti D 《The anatomical record. Part A, Discoveries in molecular, cellular, and evolutionary biology》2004,281(2):1303-1307
In this study, we investigated the angiogenic response induced by acellular aortic matrices implanted in vivo onto the chick embryo chorioallantoic membrane (CAM), a useful model for such investigation. Results showed that acellular matrices were able to induce a strong angiogenic response comparable to that of fibroblast growth factor 2 (FGF-2), a well-known angiogenic cytokine. The angiogenic response was further increased when exogenous FGF-2 or transforming growth factor beta 1 (TGF-beta1) were added to the matrices and inhibited by the addition of an anti-FGF-2 or anti-TGF-beta1 antibodies. The response may be considered dependent on a direct angiogenic effect exerted by the matrices and in part also by the presence of FGF-2 and TGF-beta1 in the acellular matrices. 相似文献
3.
Role of surface-exposed loops of Haemophilus influenzae protein P2 in the mitogen-activated protein kinase cascade
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Galdiero S Capasso D Vitiello M D'Isanto M Pedone C Galdiero M 《Infection and immunity》2003,71(5):2798-2809
The outer membrane of gram-negative bacteria contains several proteins, and some of these proteins, the porins, have numerous biological functions in the interaction with the host; porins are involved in the activation of signal transduction pathways and, in particular, in the activation of the Raf/MEK1-MEK2/mitogen-activated protein kinase (MAPK) cascade. The P2 porin is the most abundant outer membrane protein of Haemophilus influenzae type b. A three-dimensional structural model for P2 was constructed based on the crystal structures of Klebsiella pneumoniae OmpK36 and Escherichia coli PhoE and OmpF. The protein was readily assembled into the beta-barrel fold characteristic of porins, despite the low sequence identity with the template proteins. The model provides information on the structural features of P2 and insights relevant for prediction of domains corresponding to surface-exposed loops, which could be involved in the activation of signal transduction pathways. To identify the role of surface-exposed loops, a set of synthetic peptides were synthesized according to the proposed model and were assayed for MEK1-MEK2/MAPK pathway activation. Our results show that synthetic peptides corresponding to surface loops of protein P2 are able to activate the MEK1-MEK2/MAPK pathways like the entire protein, while peptides modeled on internal beta strands are unable to induce significant phosphorylation of the MEK1-MEK2/MAPK pathways. In particular, the peptides corresponding to loops L5 (Lys206 to Gly219), L6B (Ser239 to Lys253), and L7 (Thr280 to Lys287) activate, as the whole protein, essentially JNK and p38. 相似文献
4.
The study aim was to evaluate the effect of different attentional tasks on the amplitudes and latencies of painful and non-painful contact heat evoked potentials (CHEPs). CHEPs were recorded in 12 healthy subjects during two experimental conditions, in which attention was oriented towards the intensity and the distress caused by the stimuli and were compared with CHEPs recorded during a neutral condition. The painful heat stimulation produced a negative potential at Cz vertex with a latency around 540 ms (Cz/N540), a positive peak at Cz electrode around 730 ms (Cz/P730) and, lastly, a positive peak around 1000 ms (Pz/P1000) in the Pz traces. The Cz/P730 wave was significantly higher in amplitude only during the painful stimulation and is probably related to coding the nociceptive activity. Varying the attentional target towards different properties of the stimulus did not cause any significant change in CHEP responses amplitude and latencies compared with the neutral condition. Our results suggest that CHEPs represent a reliable functional measure of the nociceptive pathways and that they are generated by the activation of different cerebral areas involved in pain processing. The high activation level of each of these area or their spatial neighbouring might explain the strong similarity of CHEP components recorded during different attentional manipulations. 相似文献
5.
Massimiliano Valeriani Domenico Restuccia Vincenzo Di Lazzaro Domenica Le Pera Carmen Barba Pietro Tonali François Mauguiere 《Experimental brain research. Experimentelle Hirnforschung. Expérimentation cérébrale》1998,120(3):306-315
Brain electrical source analysis (BESA) of the scalp electroencephalographic activity is well adapted to distinguish neighbouring
cerebral generators precisely. Therefore, we performed dipolar source modelling in scalp medium nerve somatosensory evoked
potentials (SEPs) recorded at 1.5-Hz stimulation rate, where all the early components should be identifiable. We built a four-dipole
model, which was issued from the grand average, and applied it also to recordings from single individuals. Our model included
a dipole at the base of the skull and three other perirolandic dipoles. The first of the latter dipoles was tangentially oriented
and was active at the same latencies as the N20/P20 potential and, with opposite polarity, the P24/N24 response. The second
perirolandic dipole showed an initial peak of activity slightly earlier than that of the N20/P20 dipolar source and, later,
it was active at the same latency as the central P22 potential. Lastly, the third perirolandic dipole exaplaining the fronto-central
N30 potential scalp distribution was constantly more posterior than the first one. In order to evaluate the effect of an increasing
repetition frequency on the activity of SEP dipolar sources, we applied the model built from 1.5-Hz SEPs to traces recorded
at 3-Hz and 10-Hz repetition rates. We found that the 10-Hz stimulus frequency reduced selectively the later of the two activity
phases of the first perirolandic dipole. The decrement in strength of this dipolar source can be explained if we assume that:
(a) the later activity of the first perirolandic dipole can represent the inhibitory phase of a “primary response”; (b) two
different clusters of cells generate the opposite activities of the tangential perirolandic dipole. An additional finding
in our model was that two different perirolandic dipoles contribute to the centro-parietal N20 potential generation.
Received: 5 August 1997 / Accepted: 26 November 1997 相似文献
6.
Patrizia Canale Francesco Squadrito Domenica Altavilla Mariapatrizia Ioculano Basilia Zingarelli Giuseppe M. Campo Giuseppe Urna Aurora Sardella Giovanni Squadrito Achille P. Capuli 《Inflammation research》1994,42(3-4):128-134
The aim of this study was to evaluate: (1) the accumulation of leukocytes in the ileum and the lung during splanchnic artery occlusion (SAO) shock; (2) the role of platelet-activating factor (PAF) and tumor necrosis factor (TNF-) in this phenomenon. Untreated anesthetized rats subjected to total occlusion of the celiac, superior and inferior mesenteric arteries for 45 min, followed by reperfusion, uniformly died within 90 min after reperfusion. The mean survival time was 93±7 min. The neutrophilic infiltrate was quantitated in the ileum and in the lung using a myeloperoxidase (MPO) assay. MPO activity in the ileum and in the lung averaged 0.05±0.03 and 0.4±0.02 U×10–3/g protein in animals killed before occlusion. MPO activity did not change in rats killed immediately before reperfusion and was significantly elevated (0.11±0.02 and 1.7±0.6 U×10–3/g protein in the ileum and the lung, respectively) in those killed 80 min after the beginning of the reperfusion. The histological examination confirmed the accumulation of leukocytes in the mucosa of the ileum and the lung over the 80 min. SAO shocked rats exhibited leukopenia and increased serum levels of TNF-. In order to evaluate the role of PAF and TNF- in SAO shock, a powerful PAF receptor antagonist, TCV-309 (5 g/kg i.v.), was injected 5 min after reperfusion. TCV-309 increased survival time, lowered serum TNF-, reduced MPO activity in both the ileum and the lung and ameliorated leukopenia induced by SAO shock. In addition, the drug significantly reduced ileal necrosis and pulmonary morphological alterations induced by shock. These results suggest an important role for PAF in the adhesion of leukocytes in SAO shock. 相似文献
7.
The survival of a group of 115 patients (group A) who entered a follow-up program after apparently "curative" surgery for colorectal cancer was compared with that of 62 similar patients (group B) who did not join such a program. No significant difference was found. Clinical benefits to single patients in group A, in terms of anticipated diagnosis and effective treatment of recurrences and of metachronous neoplasias, appeared to be, if any, extremely limited. In light of the high costs of intensive follow-up programs, it is concluded that their use can be justified only within controlled perspective trials aimed to evaluate their usefulness. 相似文献
8.
Ph.D M.D. Geno Saccomanno M.D. Victor E. Archer M.D. Oscar Auerbach M.D. Richard P. Saunders 《Human pathology》1973,4(4):487-495
Eight selected cases are presented to show different effects of the environment on the lung. Some appear to lack resistance to environmental carcinogens. The variations in response and an assessment of the carcinogens involved are discussed. Further study of these poorly understood etiologic factors is needed. 相似文献
9.
In patients undergoing permanent cardiac pacing, the maintenance of atrial contractility is important to ensure adequate ventricular filling and to guarantee an optimal ventricular ejection capacity. The appropriate pacing mode, assuring a suitable mechanical atrioventricular coupling, prevents the onset of atrial fibrillation and contributes to reduction of the risk of subsequent systemic and pulmonary thromboembolic episodes. We examined 461 patients (266 males and 195 females, aged between 52 and 97 years, average age 76.5 +/- 18) paced for conduction disturbances of various degrees and etiology. Of them, 323 patients received ventricular demand pacemaker (VVI group, average age 77.9 years); 138 underwent dual chamber pacing (DCP group, average age 75.2 years), 117 of the latter received universal demand pacing (DDD) and 21 atrial synchronous ventricular demand pacing (VDD). The patients were subsequently divided into two age-groups: Group A (= 75 years, 174 patients), and Group B (>/= 75 years, 287 patients). According to pacing mode and successive development of stable atrial fibrillation (AF), we analysed the occurrence of systemic and/or pulmonary thromboembolic episodes and the incidence of fatal events. During our study, performed from January 1986 to August 1993, 70 embolic episodes were observed in the VVI group and six in the DCP group. Eighty-four patients with VVI units developed AF during follow-up, compared with only five patients in the DCP group. Our data indicate that VVI patients have a higher incidence of AF, embolic complications and cerebrovascular mortality, in comparison with the DCP group. VVI pacing should be avoided, especially in older patients, when atrial rhythmical activity is present. 相似文献
10.