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71.
Farida Daïkha-Dahmane Françoise Narcy Marc Dommergues Mireille Lacoste Agnes Beziau Marie-Claire Gubler 《Pediatric nephrology (Berlin, Germany)》1997,11(3):267-273
An alteration in cell/matrix interactions is one of the suggested mechanisms leading to cyst formation in polycystic kidney
diseases. Most of these interactions are mediated by β1-integrins, a subfamily of integrin receptors, formed by the association
of the β1-chain with different α-subunits. To date, no study on α-integrin subunit distribution during the early stages of
cyst development has been reported. Using immunofluorescence, we analyzed the distribution of α-integrin subunits (α1, α2,
α3, α5, and α6) and basement membrane proteins in kidneys of fetuses with autosomal dominant (ADPKD) or autosomal recessive
polycystic kidney disease (ARPKD). The distribution was compared with that observed in normal fetal and post-natal kidneys,
and in fetal cystic dysplasia and Meckel syndrome. Marked increase in α1-integrin staining was observed in normal and cystic
collecting duct cells of both polycystic diseases (PKD), compared with normal and cystic controls. The distribution of integrin
subunits α2, α3, and α6 was irregular in cyst epithelial cells of PKD and cystic controls. The increased expression of the
α1-subunit specifically observed in PKD collecting duct cells may be an early consequence of the genetic defect in ARPKD.
In ADPKD it parallels the reported expression of polycystin, the protein product of PKD1. The irregular expression of α2,
α3, and α6 integrin subunits observed in all types of cysts suggests that cell/matrix interactions are altered early and may
participate in the development of cysts, perhaps by contributing to the deregulation of cell survival in cystic diseases.
Received May 28, 1996; received in revised form October 2, 1996; accepted October 25, 1996 相似文献
72.
A. C. Iplikçioğlu M. A. Bayar F. Kökeş B. Yildiz C. Gökçek Z. Buharali 《Neuroradiology》1994,36(1):31-32
We report a fluid level in an acute extradural haematoma developing after placement of a ventriculoperitoneal shunt for hydrocephalus. This fluid level was thought to be due to a mixture of blood and cerebrospinal fluid. 相似文献
73.
Milton Carlos Gon?alves Salvador Accácio Lins do Valle Mariana Carvalho Mandim Ribeiro Jefferson Ricardo Pereira 《Journal of applied oral science : revista FOB》2007,15(1):9-13
A group of destructive changes occurring in jaws in patients with maxillary complete dentures and mandibular removable partial dentures (bilaterally) has been described in the literature as the combination syndrome. However, this condition is not clinically observed in all patients. The aim of this study was to establish the prevalence index on signs of combination syndrome and to verify whether these changes also occurred in patients rehabilitated with a mandibular removable partial denture (unilaterally). Sample was composed of 44 patients, completely edentulous in the maxilla. Thirty-two patients had a Kennedy Class I removable partial denture and 12 a Kennedy Class II. Three major alterations were observed in 20.5% of the studied population. Nevertheless, these changes were present only in 25% of patients with Kennedy Class I removable partial denture. Based on the findings of this study, it can be concluded that patients with Kennedy Class II removable partial denture do not have similar signs that lead to the combination syndrome’s condition. 相似文献
74.
Laryngeal pleomorphic rhabdomyosarcoma 总被引:2,自引:0,他引:2
M. U. Akyol B. Sözeri T. Küçükali O. Ög˘retmenog˘lu 《European archives of oto-rhino-laryngology》1998,255(6):307-310
A case of an extremely unusual tumor of the larynx, pleomorphic rhabdomyosarcoma, is presented with a review of literature.
This is the fifth case of this malignancy described in the larynx in the English language literature. A histopathological
diagnosis was made with immunohistochemistry and electron microscopy. In contrast to other reported cases, the tumor in the
present case had a very aggressive behavior. Despite radical surgery involving total laryngectomy and neck dissection followed
by radiation therapy, the patient died of disease 8 months following treatment.
Received: 14 March 1997 / Accepted: 23 January 1998 相似文献
75.
Yannick Poquet Patricia Constant Franck Halary Marie-Alix Peyrat Martine Gilleron François Davodeau Marc Bonneville Jean-Jacques Fournié 《European journal of immunology》1996,26(10):2344-2349
The stimulation of human γδ T cells by mycobacteria occurs through recognition of four distinct nonpeptide phosphorylated antigens termed TUBag1–4. Among these latter, TUBag4 has already been biochemically characterized as a γ-X derivative of 5′-deoxythymidine triphosphate (Constant, P., Davodeau, F., Peyrat, M. A., Poquet, Y., Puzo, G., Bonneville, M. and Fournié, J.-J., Science 1994. 264: 267). However, despite chemical synthesis of weakly stimulatory nucleotide-containing analogs, these mycobacterial compounds remained the sole nucleotide-containing antigens actually isolated from natural sources. Here, we present the complete isolation of the TUBag3 antigen from Mycobacterium fortuitum and demonstrate that this nonpeptide molecule contains a 5′-UTP nucleotide moiety. On selected Vγ9/Vδ2 clones, T cell responses can be triggered with nanomolar concentrations of TUBag3. Like crude mycobacterial extracts, this purified nucleotide conjugate elicits a strong polyclonal response of γδ PBL from healthy donors. Furthermore, we present evidence that this compound is distinct from the recently synthesized γ-isopentenyl 5′-UTP, a nucleotide conjugate of isopentenyl pyrophosphate that was found to be stimulatory for human γδ T cells (Tanaka, Y., Morita, C. T., Tanaka, Y., Nieves, E., Brenner, M. B. and Bloom, B. R., Nature 1995. 375: 155). Since it appears that both mycobacterial nucleotide antigens are molecules structurally related to peculiar precursors of nucleic acid synthesis, we propose that TUBag-reactive T cells might be specifically devoted to surveillance of proliferating cells. 相似文献
76.
França O 《The Hastings Center report》1988,18(4):S21-S22
The ethics of care for the terminally ill in Uruguay spring from deeply rooted attitudes which invest the physician with sole power to determine the course of treatment, even to prescribe painkilling drugs and to hasten death actively or passively, without collaboration from the patient's family. The paternal function attributed to the physician has not been questioned by any systematic reflection on biomedical ethics. However, conscientious physicians are interested in these issues and are well informed about the concerns of their foreign colleagues. 相似文献
77.
The reinvestigation of the aerial parts of ARTEMISIA SANTONICUM afforded, in addition to three known eudesmanolides, six new ones, all closely related to taurin. The structures were elucidated by high-field NMR spectroscopy. 相似文献
78.
J F Vaz M R Elmor L M Gon?alves 《Revista do Instituto de Medicina Tropical de S?o Paulo》1992,34(6):527-534
In order to know the distributional patterns of Basommatophoran snails in the state of S?o Paulo (Brazil), 85 "counties" in the area of S. José do Rio Preto were worked out during seven months (1982). Snails from 286 breeding places were collected and identified. Biomphalaria straminea, an intermediate host of S. mansoni, was found in four little ponds, in the neighbourhood of Altair and S. José do Rio Preto. It was concluded that schistosomiasis has little chance to spread out in the studied area. 相似文献
79.
Cuff pressure of endotracheal tubes increases to dangerous levels during anesthesia with nitrous oxide. In a small clinical study the Authors conclude that Mallinckrodt-Brandt endotracheal tubes are the only "low pressure" tubes available at the moment. 相似文献
80.
J. Gonçalves F. Carvalho S. Guimarães 《Naunyn-Schmiedeberg's archives of pharmacology》1989,339(3):288-292
Summary The present study was undertaken to compare the presynaptic interaction of neuronal noradrenaline uptake inhibitors with imidazoline and phenylethylamine 2adrenoceptor agonists under two different conditions: at low and high noradrenaline concentrations in the biophase.Isolated mouse vasa deferentia were stimulated with trains of 7 pulses given at 0.2 Hz and the inhibition by the 2-adrenoceptor agonists clonidine, -methylnoradrenaline, and UK-14,304 of twitch responses was measured in the absence and in the presence of either cocaine (12 mol/l) or desipramine (40 nmol/l). The effects were determined for the first (equivalent to single pulse stimulation) and the last stimulus of each train. Both uptake inhibitors antagonized the presynaptic inhibitory effects of imidazolines (clonidine and UK-14,304) on the last twitch; the effects on the first twitch remained unchanged. In contrast, the uptake inhibitors potentiated the inhibitory effect of the phenylethylamine (-methylnoradrenaline) on both the first and the last twitches.These results support the view that the concentration of noradrenaline in the biophase plays a decisive role in the inhibition by a2-adrenoceptor agonists of the electrically evoked release of noradrenaline. Agonists that are not substrates of neuronal uptake (i.e., clonidine, UK-14,304) become less effective when noradrenaline is present in the biophase while substrates of neuronal uptake (i. e., -methylnoradrenaline) do not. The results argue against the hypothesis that uptake inhibitors interact directly with presynaptic 2-adrenoceptors or act at some link between uptake and receptor sites.
Send offprint requests to S. Guimarães at the above address 相似文献