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991.
Trevizan MA Mendes IA Lourenço MR Melo MR 《Revista latino-americana de enfermagem》2003,11(5):652-657
In this study, authors characterize nurse's managerial conduct in the perspective of the work, illustrated through the analysis of three investigations. Understanding the fragility of managerial nurse's situation, considering the commitment with the users and with the ones who provide the services, authors advocate in favor of an intervention to change this situation. Therefore, they propose an alternative of reflection about the changes that are necessary. They defend a new ethics articulating a new sense of providing care proposed by Boff, in which the relationship is based on the companionship, interaction and sharing. According to this way of being, nurse's care is an attitude of concern, responsibility and affective commitment with the other. Thus, the instrumental reasoning is substituted by the sensible reasoning and the spirit of deep feelings. Considering these new values, nurses understand better the other's dimension, the respect, reciprocity, and complementarity in the managerial relationship. 相似文献
992.
Schestatsky S Shansis F Ceitlin LH Abreu PB Hauck S 《Revista brasileira de psiquiatria (S?o Paulo, Brazil : 1999)》2003,25(Z1):8-11
The authors elaborate on the historical evolution of the concept of Posttraumatic Stress Disorder (PTSD). The authors quote the French scholars, mainly Charcot and Janet, as the first to connect traumatic events and symptoms of hysteria. The contributions of Freud are described with enphasis on his effort into integrating the intra-psychic and environmental dimensions. Kardiner is referred as the author who coined the concept of 'war neurosis', which was deemed as an important one during the Second World War and Vietnam War. In conclusion, the authors highlight that the concept of PTSD used in the Diagnostic and Statistical Manual of Mental Disorders (DSM) by the American Psychiatric Association assess, at the same time, how treatening was the traumatic event and the list of symptoms presented by the patients. 相似文献
993.
Haemangiomas are common benign tumours of the head and neck region in children. The nasal cavity, however, is an extremely rare site for such lesions in childhood. We present the typical MRI features of a nasal cavity haemangioma in a 12-year-old girl. Biopsy was avoided because of the MRI diagnosis and preoperative embolization of the mass was performed. 相似文献
994.
Stromal cell-derived factor 1alpha stimulates human glioblastoma cell growth through the activation of both extracellular signal-regulated kinases 1/2 and Akt 总被引:18,自引:0,他引:18
Barbero S Bonavia R Bajetto A Porcile C Pirani P Ravetti JL Zona GL Spaziante R Florio T Schettini G 《Cancer research》2003,63(8):1969-1974
In this paper, we describe the role of chemokine receptor CXCR4 activation by its natural ligand, the chemokine stromal cell-derived factor (SDF-1) (CXCL12), in glioblastoma cell growth in vitro. We show that both CXC chemokine receptor 4 (CXCR4) and SDF-1 mRNA are expressed in several human glioblastoma multiforme tumor tissues and in two human glioblastoma cell lines, U87-MG and DBTRG-05MG. These cells are able to secrete SDF-1 under basal conditions, and the rate of secretion is highly increased after lipopolysaccharide or 1% fetal bovine serum treatment. Exogenous SDF-1alpha induces proliferation in a dose-dependent manner in both cell lines. Moreover, we observed that SDF-1alpha-dependent proliferation is correlated with phosphorylation and activation of both extracellular signal-regulated kinases 1/2 and Akt and that these kinases are independently involved in glioblastoma cell proliferation. The role of CXCR4 stimulation in glioblastoma cell growth is further demonstrated by the ability of human monoclonal CXCR4 antibody (clone 12G5) to inhibit the SDF-1alpha-induced proliferation as well as the proliferation induced by SDF-1-releasing treatments (lipopolysaccharide and 1% fetal bovine serum). These data support a role for SDF-1alpha in the regulation of glioblastoma growth in vitro, likely through an autocrine/paracrine mechanism. 相似文献
995.
Alpha-methylacyl-CoA racemase as an androgen-independent growth modifier in prostate cancer 总被引:11,自引:0,他引:11
Zha S Ferdinandusse S Denis S Wanders RJ Ewing CM Luo J De Marzo AM Isaacs WB 《Cancer research》2003,63(21):7365-7376
Alpha-methylacyl-CoA racemase (AMACR) is an enzyme involved in beta-oxidation of branched-chain fatty acids and bile acid intermediates. Recent work has identified AMACR as a new diagnostic marker for prostate cancer (PCa). The data from the present study suggest that AMACR is also functionally important for the growth of PCa cells. Overexpressed AMACR from both clinical tissues and PCa cell lines is wild type by sequence analysis and functionally active by enzymatic assay. Correspondingly, enzyme activity of AMACR increases approximately 4-fold in PCa in comparison with adjacent normal prostate. Small interference RNA (siRNA) against AMACR, but not the control inverted siRNA, reduced the expression of AMACR and significantly impaired proliferation of the androgen-responsive PCa cell line LAPC-4. No effect was observed in HeLaS3 cells, which express AMACR at a low level. Cell cycle analyses revealed a G(2)-M cell cycle arrest in LAPC-4 cells treated with siRNA compared with mock treatment or control inverted siRNA. Expression of a siRNA-resistant form of AMACR in LAPC-4 cells protects the cells from growth arrest after AMACR-specific siRNA treatment. Data from Western blotting and luciferase-based reporter assays suggest that the function and expression of AMACR are independent of androgen receptor-mediated signaling. Moreover, simultaneous inhibition of both the AMACR pathway by siRNA and androgen signaling by means of androgen withdrawal or antiandrogen suppressed the growth of LAPC-4 cells to a greater extent than either treatment alone. Taken together, these data suggest that AMACR is essential for optimal growth of PCa cells in vitro and that this enzyme has the potential to be a complementary target with androgen ablation in PCa treatment. 相似文献
996.
997.
Macchia M Bertini S Fogli S Giovannetti E Minutolo F Rapposelli S Danesi R 《Il Farmaco; edizione pratica》2003,58(3):205-211
A survey on the role played by ceramide within the sphingolmyelin pathway is here reported, taking into account its importance as an intracellular effector molecule in apoptosis. Recently, several analogs of ceramide, able to pass the cell membrane and then to induce apoptosis, have been developed as a new potential approach in anticancer therapy. 相似文献
998.
Macchia M Antonello M Bertini S Di Bussolo V Fogli S Giovannetti E Minutolo F Rapposelli S Danesi R 《Il Farmaco; edizione pratica》2003,58(1):85-89
Conformationally restrained analogues of ceramide containing thiouracil or uracil moieties in their polar head, substituted with an ethyl group in their 6-positions, proved to inhibit cell proliferation and induce apoptosis. A series of new thiouracil and uracil analogues of ceramide possessing several 6-alkyl- or 6-arylalkyl-substituents, were synthesized and tested as inhibitors of cell proliferation. The lipophilic substituents introduced in the 6-position were pure alkyls (n-propyl, n-butyl, i-butyl, neo-pentyl), or aryl-alkyls (2-phenylethyl). Although a significant antiproliferative activity was maintained in most compounds synthesized, none of them showed any improvement with respect to their 6-ethyl-substituted counterparts. 相似文献
999.
Bonavia R Bajetto A Barbero S Pirani P Florio T Schettini G 《Toxicology letters》2003,139(2-3):181-189
The study of chemokine role in the CNS indubitably represents an important step to understanding many aspects of brain pathology, physiology and development. Here we discuss our recent research on the expression of chemokines and chemokine receptors in brain tissues and in cultured CNS cells, with particular regard to the CXCL12/SDF-1-CXCR4 system. We showed their expression in both glial and neuronal cells in basal conditions and their modulation upon stimulation. We demonstrated that CXCL12/SDF-1 in vitro act as a growth factor for astrocytes by stimulating their proliferation, a phenomenon that could represent the basis of pathological conditions such as gliosis and malignant transformation. We investigated the signal transduction pathways, identifying in the sequential activation of G-protein-PI-3Kinase-ERK1/2 the main signaling cascade linked to the CXCL12/SDF-1-induced proliferation in astrocytes. 相似文献
1000.
de Melo AL Silva-Barcellos NM Demicheli C Frézard F 《International journal of pharmaceutics》2003,255(1-2):227-230
The aim of the present study was to evaluate the ability of liposomes to improve the efficacy of tartar emetic (TA) against established Schistosoma mansoni infection. TA was used as a schistosomicidal drug model and both conventional liposomes (CL) and long-circulating pegylated liposomes (LCL) were evaluated. In the first experiment, TA, either free or encapsulated within CL or LCL, was given intraperitoneally (i.p.) as a single dose of 11 mg Sb/kg to mice experimentally infected with S. mansoni. Only the group treated with LCL showed a significant (55%) reduction in the worm burden, compared to the control groups (untreated or treated with empty LCL). In the second experiment, the efficacy of TA-containing LCL was evaluated at a higher dose (27 mg Sb/kg) by both subcutaneous (s.c.) and i.p. routes. Reduction levels of 67 and 82% were achieved by s.c. and i.p. routes, respectively. Strikingly, all mice survived to this high dose of antimony. This is in contrast with free TA that was lethal in 100% of mice at the same dose. The present work demonstrates that LCL reduce the acute toxicity of TA and effectively deliver this drug to S. mansoni during the late stages of parasite infection. 相似文献