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991.
This article aims at characterizing nurse's and nursing assistant's work process, as well as at analyzing contradictions present in nursing work. Studies on the nursing and health work process, and the communicative action theory were used as its theoretical framework. Based on qualitative research methodology, the empirical material was collected by means of semi-structured interviews with nurses, nursing assistants and physicians on the same work team in a school hospital. Analysis was conducted through the impregnation technique and the identification of thematic units, which were interpreted on basis of analytical categories from the theoretical framework. Results showed contradictions such as the separation between planning and care delivery and the absence of appropriation of nursing knowledge by the agents who are in charge of delivering care.  相似文献   
992.
We determined the influence of melatonin (MLT) on the induction of interleukin (IL)-2, IL-1 beta, IL-4, tumour necrosis factor-alpha (TNF-alpha) and gamma interferon (IFN-gamma) on mice infected with the Venezuelan equine encephalomyelitis (VEE) virus. Levels of IFN-gamma in the MLT-treated group were significantly increased (P < 0.001) when compared with the control non-infected group from day 1 to 6 post-infection (p.i.), while in infected mice treated with 500 micrograms MLT/kg of bodyweight enhanced levels of IFN-gamma were evident from 4 to 6 days p.i. No differences were detected in the levels of IL-2 between the controls, the infected mice treated with MLT and the infected untreated group, from day 2 p.i. No changes in serum levels of IL-4 were detected. In infected mice treated with MLT, blood levels of IL-1 beta were elevated almost 10-fold from day 1 to day 6 p.i. when compared to the control, the infected and the non-infected MLT-treated mice (P < 0.001). A highly significant rise (P < 0.001) of TNF-alpha was found in infected mice treated with MLT, from day 1 to 6 p.i. when compared to the other groups. A significant rise (P < 0.001) was also evident in the infected non-MLT-treated group and a less pronounced rise in the non-infected mice treated with MLT when compared to controls. The blockade of IFN-gamma and TNF-alpha did not inhibit the protective effect of MLT but when IL-1 beta was neutralized, 100% of the infected mice died suggesting that IL-1 beta induced by MLT treatment is a target cytokine to generate an immune response against the viral infection.  相似文献   
993.
Relationship conflict has long been thought to cause, maintain, and influence the therapeutic outcome of sexual problems in the absence of a physical cause. The results of conflict can influence partners' relationship satisfaction, and relationship satisfaction can influence sexual satisfaction. General relationship deficiencies, such as unresolved conflict, undermine the mutual acceptance that is important to healthy sexual functioning. The purpose of this article is to summarize some of the basic empirical findings of studies of conflict patterns in relationships and their role in sex dysfunction and to suggest a model for assessing relationship conflict as a feature of sexual dysfunction. Results from several studies indicate that couples with sexual problems may have conflict-management issues and employ distinct conflict-resolution styles compared to satisfied couples. Dysfunctional conflict resolution may be a cause or result of some sexual problems, whereas constructive interaction concerning conflict can add to emotional and sexual intimacy in a couple's relationship. These patterns warrant systematic attention in assessment and intervention in sex therapy.  相似文献   
994.
The Brazilian dental care sector is facing a paradoxical crisis characterized by a surplus of dentists and a large contingent of people lacking dental care, thus highlighting the need to improve management strategies. One necessary step is to analyze the various payment schemes for dental services. This paper reviews two important approaches, fee for service and capitation, and considers the impacts and consequences of payment strategies on the dental care system.  相似文献   
995.
This study was conducted among health care personnel (registered nurses and nurse aides) in a public hospital in S?o Paulo, Brazil. Work was organized in 12-hour daytime or nighttime shifts, followed by 36 hours off. The study aimed to evaluate how the nursing staff perceived the duration and quality of sleep both during and off work days, as well as their perception of alertness during working hours. There were significant differences between night and day in the duration of sleep (Student t test = 10.82; p < 0.000). Quality of daytime sleep after working night shifts was perceived as worse than nighttime sleep (Wilcoxon test, Z = 2.67; p < 0.007). Significant differences were detected in self-evaluation of alertness after the 2nd, 6th, and 10th hour of night shifts (Friedman = 63.0; p < 0.00). Alertness was perceived as worse during dawn hours. This is an indication of sleepiness at work and can have serious consequences for both health care workers and patients.  相似文献   
996.
Systemic injection of lipopolysaccharide (LPS) blocks the expression of long-term potentiation in the hippocampus of the rat. This is coupled with increased IL-1beta concentration and c-Jun NH(2)-terminal kinase activity, as well as an increase in the number of cells displaying apoptotic characteristics in the hippocampus. Vasogen's Immune Modulation Therapy (IMT) is a procedure involving intramuscular administration of syngeneic blood which has been exposed ex vivo to elevated temperature, oxidation and ultraviolet light. We report that Vasogen's IMT significantly abrogates these LPS-induced effects with a concomitant increase in the concentration of the anti-inflammatory cytokine IL-10. These data suggest that Vasogen's IMT may play a protective role against the deleterious effects of immune insults in the brain.  相似文献   
997.
998.
The aim of this study was to verify the symmetry of cerebral blood flow changes during the generalized spike-wave discharges of typical absence seizures. A recording of mean flow velocity in the left and right middle cerebral arteries and of electroencephalographic activity was performed simultaneously in two subjects with multiple daily absence seizures. A total of 12 generalized spike-wave discharges were recorded. Mean flow velocities showed a significant increase during the discharges with respect to baseline. The increase of flow velocity started simultaneously or a few seconds before the discharges. In 91.6 % of all recordings, the percentage increase of mean flow velocity was significantly higher in the left than in the right side (7.03 % ± 3.3 vs 5.14 % ± 3.3; p < 0.1). The extent of the following decrease of flow velocity was also significantly greater in the left than in the right side (-16.91 % ± 8.1 vs -14.07 % ± 8.3; p < 0.01). These findings show an inter-hemispheric asymmetry in cerebral blood flow during generalized spike-wave discharges in two patients with absence seizures. Transcranial Doppler ultrasonography promises to be an interesting approach to detect rapid changes in cerebral hemispheric activity not otherwise recognizable. Received: 14 November 2001, Received in revised form: 18 February 2002, Accepted: 5 March 2002  相似文献   
999.
Statins appear to have beneficial effects on fibrous cap stabilisation but their effects on plaque thrombogenicity have not been reported. To evaluate the thrombogenicity of human carotid plaques before and after atorvastatin treatment, 59 patients with bilateral carotid stenosis eligible for two-step carotid endoarterectomy (CEA) were randomly assigned to atorvastatin, 20 mg/day, or placebo. Histological and immunohistochemical analyses, Tissue Factor (TF), Tissue Factor Pathway Inhibitor (TFPI) antigens (Ag) and TF activity were determined in endoarterectomy specimens obtained at baseline and after treatment. Mean TFAg and TFPIAg levels from plaques removed at the first CEA were 55 +/- 56 and 32 +/- 26 pg/mg. After placebo, TFAg and TFPIAg content was higher in the second than the first CEA. Plaques removed at the second CEA from atorvastatin-treated patients had a lower macrophage content than plaques at the first CEA. TFAg and TFPIAg levels, and TF activity in plaques after atorvastatin treatment were lower (respectively 29, 18% and 56%) than after placebo. These findings indicate that atorvastatin reduce the inflammatory/thrombotic phenotype of carotid plaque, suggesting that these drugs may indeed have a beneficial effect on cerebrovascular events.  相似文献   
1000.
Plasmin triggers chemotaxis and NF-kappa B- and AP-1-mediated proinflammatory gene expression in human peripheral monocytes (PM). Compared with macrophages and dendritic cells, PM express mainly the peroxisome proliferator-activated receptor (PPAR) gamma and traces of PPAR alpha as detected by semiquantitative RT-PCR and immunoblotting. The PPAR gamma agonist ciglitazone, but not the PPAR alpha agonist clofibric acid, concentration-dependently inhibited the plasmin-, but not the FMLP-induced PM chemotaxis. Similarly, release of interleukin (IL)-1 alpha, IL-1 beta and tumor necrosis factor (TNF)-alpha from plasmin-stimulated PM was concentration-dependently inhibited by ciglitazone, but not by clofibric acid, while the LPS-induced TNF-alpha release remained unaffected by any of both PPAR agonists. Ciglitazone activates PPAR gamma as shown by a novel surface plasmon resonance analysis and inhibits the plasmin-induced activation of NF-kappa B and AP-1. It also inhibits p38 MAPK phosphorylation essential for the plasmin-induced PM chemotaxis and gene activation. Thus, activation of PPAR gamma by ciglitazone may allow controLling of the plasmin-mediated recruitment and activation of PM at sites of inflammation.  相似文献   
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