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81.
Cognitive factors in student nurses' clinical problem solving   总被引:2,自引:0,他引:2  
Rationale, aims and objectives The assumption that the acquisition and mastery of the nursing process alone is sufficient to explain problem‐solving performance has been challenged in recent literature. Researchers have argued that the quality of prior knowledge is a key component in explaining performance. In addition, motivational orientation and the quality of reasoning have been found to have different effects on performance in cognitive tasks. The aim of this study is to explore student nurses’ clinical problem solving based on a model consisting of their motivational orientation, prior knowledge, diagnostic reasoning and diagnostic solutions. Methods One hundred and thirty‐five second‐year nursing students completed the Study Process Questionnaire and the Causal Attribution Questionnaire prior to receiving five lectures on mental illness. A knowledge test and a clinical problem‐solving task provided measures of prior knowledge, quality of diagnostic reasoning, and the quality and comprehensiveness of nursing diagnosis. A correlational design using pairwise correlations, hierarchical regression and path analysis examined the relationships among these data. Results and conclusions The results indicated an important role for a belief in personal control, for the accessibility and structuring of prior knowledge, and the quality of diagnostic reasoning, in generating high quality and comprehensive nursing diagnoses. The findings suggest that all contributing components of clinical problem solving need to be addressed in nursing education.  相似文献   
82.
BACKGROUND/AIM: Recently emerging evidence suggests that oxidative stress (SOX) may participate in atherogenesis. The aim of the present study was to establish whether enhanced SOX, involving endothelial injury, activation of coagulation, and inflammatory reaction, could be implicated in atherosclerotic diseases in haemodialysis (HD) patients. METHODS: Markers of SOX, endothelial injury, coagulation, and cytokines, were measured in the plasma of HD patients with and without cardiovascular disease (CVD), and of healthy controls by ELISA methods. Remodeling of the carotid arteries was assessed by measuring the intima-media thickness (IMT) as a surrogate of atherosclerotic disease in all groups. RESULTS: Markers of SOX, endothelial injury, and extrinsic coagulation pathway activation and IMT values were significantly elevated in HD patients, especially in those with CVD when compared with the control group. The von Willebrand factor antigen (vWF:Ag) levels were more increased in the patients with CVD than in those without. Furthermore, the plasma levels of tumour necrosis factor alpha, monocyte chemo-attractant protein 1, and macrophage inflammatory protein 1 beta were significantly higher only in the HD group with CVD when compared with the controls. The IMT was strongly and directly correlated with Cu/Zn superoxide dismutase. Both IMT and Cu/Zn superoxide dismutase were positively correlated with age, thrombomodulin, vWF:Ag, tissue factor, tissue factor pathway inhibitor, prothrombin fragment F1 + 2, monocte chemo-attractant protein 1, macrophage inflammatory protein 1 beta, and tumour necrosis factor alpha levels. Multivariate analysis identified vWF:Ag as the only independent variable significantly associated with an increased IMT. CONCLUSIONS: The present study suggests that enhanced SOX, involved pro-atherogenic cytokine and chemokines levels, endothelial injury, and coagulation activation may constitute a pathway for accelerated atherosclerosis in HD patients. The significant, independent association between IMT and vWF:Ag should be assessed in future studies to determine whether vWF:Ag elevation is causative or a by-product of the increased IMT.  相似文献   
83.
A 54-year-old woman with a history of fatigue and shortness of breath was found to have a pericardial effusion and mild mediastinal lymphadenopathy. Video-assisted pericardioscopy revealed thickened pericardium studded with multiple nodules. Histologically the tumor was diagnosed as papillary adenocarcinoma. The site of the primary tumor could not be identified. As lung cancer is one of the most frequent causes of pericardial metastases the patient was treated with cisplatin and vinblastin. Following 5 courses of chemotherapy--given over a 4 month period--the amount of pericardial effusion and pericardial thickness did not change. The material from pericardial biopsy was reexamined and positive immunostaining for calretinine was found. The final diagnosis was primary pericardial mesothelioma of epithelioid type. Palliative radiotherapy of mediastinum was planned but the patient deteriorated and died due to disease progression with venous thrombosis and superior vena cava syndrome. The case illustrates the difficulties in establishing diagnosis of primary pericardial mesothelioma which is a rare tumor with poor prognosis.  相似文献   
84.
A very rare case of patient with locally advanced hypopharyngeal cancer with solitary, large peritoneal metastasis was presented. Diagnostic imaging excluded other organs metastases (lungs, liver, bones). At 62-old patient with advanced hypopharyngeal cancer (T4N2b) a dynamical nodal progression (within 1.5 months) without primary tumour progression was observed, and number of metastatic nodes was increased from 2 to 9. Simultaneously, a solitary peritoneal metastasis was detected and other metastases were excluded. Stage of disease was determined as T4N2cM1 and patient was qualified to palliative treatment.  相似文献   
85.
Since the publication of Miodoński, Zollner and Wullstein different methods and grafting materials have been promoted in tympanoplasty. The purpose of this study was to demonstrate the anatomical and functional results of tympanoplasty in comparison with the material used. The studies included a selected group of 142 patients who were operated on because of perforation of tympanic membrane. The analysed group consisted of 112 patients when perichondrium and cartilage were used to reconstruct the tympanic membrane. The comparison group consisted of 30 patients when fascia of the musculus temporalis was used to close a defect of the eardrum. In all cases before and after operation there was made tonal audiometry with indication for air and bone conduction within range from 500 to 4000 Hz, verbal audiometry after operation with indication of speech detection and speech reception threshold using mono-syllable NLA-93 test, tympanometry after operation and evaluation of anatomical results after surgery. The comparison of operation results showed that there was no significant difference between the two groups.  相似文献   
86.
The authors present a clinical analysis of the group of 75 patients, who was treated in Department of Otolaryngology in the years 1986-2000 and who was diagnosed as adenolymphoma. The frequency of incidence of Warthin's tumour is 17,6% of all 426 cases of parotid gland's tumours. In 72 cases (96%) the tumour was localized in the superficial part, only in 3 cases (4%)--in the deep part of the gland. In one patient we observed recurrence of adenolymphoma. In one case adenolymphoma coexisted with carcinoma planoepitheliale of parotid gland.  相似文献   
87.
88.
New carbocyclic potential minor groove binders were synthesised, using 3-nitrobenzoyl chloride and aliphatic alpha,omega-diamines with three, four and five methylene fragments. The half structures, compounds IV-VI can be compared to bis-amidines, compounds X-XII to bis-netropsin. All of the compounds were investigated antiproliferative and cytotoxic effects in the standard cell line of mammalian tumour MCF-7.  相似文献   
89.
BACKGROUND: Previously, we have shown the ability of the bacteriophage T4 and its substrain HAP1 (selected for a higher affinity to melanoma cells) to reveal antimetastatic activity in a mouse melanoma model. Here, we investigated the potential phage anticancer activity in primary tumour models. MATERIALS AND METHODS: Mice were inoculated subcutaneously with B16 or LLC cells (collected from in vitro culture). Bacteriophages T4 and HAP1 were injected intraperitoneally daily (8 x 10(8)pfu/mouse, except the experiment concerning the dose-dependence). RESULTS: Treatment with purified preparations of bacteriophage T4 resulted in significant reduction of tumour size, the effect being dose-dependent. HAP1 was more effective than T4 and its activity was also dose-dependent. Parallel experiments with non-purified bacteriophage lysates resulted in significant stimulation of tumour growth. CONCLUSION: These data suggest that purified bacteriophages may inhibit tumour growth, a phenomenon with potentially important clinical implications in oncology.  相似文献   
90.
The pineal hormone melatonin exhibits immunomodulatory activity well documented in mammals and birds. The mechanism of melatonin action within the immune system is, however, poorly understood. In mammalian immune cells in vitro, melatonin acts mainly as an antiapoptotic, oncostatic and antiproliferative agent, and these effects are exerted via specific receptors or are related to its free radical scavenging activity. In previous studies we have found that in short-term chicken splenocyte cultures in vitro melatonin stimulated basil proliferation and inhibited that stimulated with phytohemagglutinin, a T-cell mitogen. This paper is devoted to the involvement of membrane receptors, previously characterised by us as MT2 (Mel(1b)) and Mel(1c) subtypes, in the above mentioned melatonin effects in chicken splenocyte cultures. For this purpose, in present study a nonselective melatonin receptor antagonist, luzindole, and the selective MT2 blocker, 4P-PDOT, were used. The effect of melatonin on second messengers, cyclic adenosine-3',5'-monophosphate (cAMP) and inositol-1,4,5-trisphosphate (IP(3)), involved in the regulation of proliferation, was examined. We have found that the stimulation of proliferation occurs via Mel(1c) receptor and is associated with the changes in intracellular second messengers concentration: a decrease in cAMP and an increase in IP(3). In contrast, in mitogen-activated splenocytes, melatonin-induced inhibition of proliferation is mediated by MT2 receptors and is related to cAMP accumulation, as well as a decrease in IP(3). In conclusion, we have demonstrated that the stimulatory and inhibitory effect of melatonin on chicken splenocytes in vitro, dependent on the magnitude of cell stimulation, resulted from two different subtypes of membrane receptors.  相似文献   
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