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991.
Qualitative methodology, originally belonging to the Social Sciences domain, has progressively incorporated to Health Research to the scepticism of many and the admiration of others. Nowadays, validity and fiability of these qualitative techniques is still questioned by a great amount of health researchers and their use provokes doubt among reviewers and other members of the scientific community. This article presents as a fundamental measure for the validity of the qualitative methodology its precise use to approach determinate research objectives specific to them and, echoing the extra issue of the Health Services Research on December 1999 on this methodology, gathers the contribution of the use of these techniques from a complementary point of view, in a Internal Communication Audit conducted in the Primary Care Services of four Regional Health Systems: Area II of the INSALUD (National Health Institute), Basque Health System, Canary Health System and Andalusian Health System.  相似文献   
992.
993.
Cellular immune response plays an important role in the clearance of hepatitis C virus (HCV). Thus, development of efficient ways to induce anti-viral cellular immune responses is an important step toward prevention and/or treatment of HCV infection. With this aim, we have constructed a replication-deficient recombinant adenovirus expressing HCV NS3 protein (RAdNS3). The efficacy of RAdNS3 was tested in vivo by measuring the protection against infection with a recombinant vaccinia virus expressing HCV-polyprotein (vHCV1-3011). Immunisation with 10(9)pfu of RAdNS3 induced anti-NS3 humoral, T helper and T cytotoxic responses. We identified eight epitopes recognised by IFN-gamma producing cells, five of them exhibiting lytic activity. Moreover, we show that RAdNS3 immunised mice were protected against challenge with vHCV1-3011 and that this protection was mediated by CD8(+) cells. In conclusion, our results suggest that adenoviral vectors encoding NS3 might be useful for the induction of prophylactic and/or therapeutic anti-HCV immunity.  相似文献   
994.
PURPOSE: To report a case of gastrointestinal sarcoma with leiomyosarcomatous differentiation metastatic to the eyelid. METHODS: Clinical data including a comprehensive ophthalmologic examination, histologic findings, a bone scan, and hospital records were reviewed. RESULTS: A 56-year-old woman with a history of esophageal cancer had a rapidly growing lesion on her right upper eyelid that was initially treated as a chalazion. A biopsy specimen of the lesion was consistent with a gastrointestinal sarcoma with leiomyosarcomatous differentiation. The esophageal tumor was reclassified after histopathologic evaluation of the eyelid specimen. Bony metastasis developed soon after excision of the eyelid lesion. The patient died 3 months after proper diagnosis of the eyelid lesion. CONCLUSIONS: This is a rare case of a metastatic leiomyosarcoma of the eyelid. To our knowledge, only two other cases of eyelid leiomyosarcoma have been described in the literature. The importance of correct histopathologic diagnosis of eyelid lesions is underscored in this case report.  相似文献   
995.
BACKGROUND: An increase in the mortality due to motor neuron disease (MND) has been reported in Spain over the past 30-40 years. It has been suggested that this increase is due to the cohort effect, but his hypothesis has not been proven. METHODS: The motor neuron disease (MND) mortality statistics by age and by gender were furnished from the Spanish National Institute of Statistics. The mortality specifically by age and the adjusted age-related rates were calculated. By Poisson regression, the cohort effect of birth on the mortality by ages has been analyzed, the cohort effect also having been analyzed by graphic methods. RESULTS: The mortality adjusted by age was declining up until 1969, as of which time it has been on the rise. Each five-year birth cohort increases the risk of dying from MND by 8.5%. CONCLUSIONS: The increase in the mortality due to MND in Spain is the result of a cohort effect.  相似文献   
996.
Interleukin-12 (IL-12) has been shown to possess potent immunoregulatory and antitumoral effects. We have evaluated the anti-oncogenic potential and the mechanisms of the antitumoral effect of in vivo adenovirus-mediated transfer of IL-12 gene in a murine model of colon cancer. AdCMVIL-12 was constructed to permit coordinated production of p40 and p35 subunits of IL-12 gene to obtain the maximum IL-12 bioactivity. Infection of murine colon cancer CT-26 cells in vitro with AdCMVIL-12 resulted in the production of high levels of IL-12. In vivo gene therapy of colon cancer nodules by intratumoral injection of AdCMVIL-12 induced a local increase in IL-12 and interferon-gamma levels and a complete regression of the tumor in 26 of 34 (76%) mice. Tumor disappeared between days 7 and 10 after vector administration. The antitumoral effect was mediated by CD8+ T cells and was associated with the generation of cytotoxic T lymphocytes against colon cancer cells. Animals that eliminated the tumor were protected against a second administration of neoplastic cells. Treatment with AdCMVIL-12 of one tumor nodule also caused regression of established tumors at distant sites. These data demonstrate that AdCMVIL-12 is a useful therapeutic tool for established colon cancer in mice and should be considered for application in humans.  相似文献   
997.
The aim of this study was to look for an ex vivo culture system for clinical application. We evaluated the ex vivo expansion of peripheral blood CD34+ cells in gas-permeable bags and whether or not an exogenous protein source would be required in these kind of cultures. We also evaluated maturation of the cells during culture. Cells were cultured for 15 days in medium supplemented with SCF, G-CSF, IL3 and IL6. The bags supported the expansion of hematopoietic cells in a similar manner to small scale flasks system: (a) the expansion means of total nucleated cells on day +5 were 12.5-fold for bag versus 5-fold for flask, on day +10 were 44.12-fold for bag versus 41-fold for flask and on day +15 were 67.7-fold for bag versus 84.2-fold for flask, (b) the peak values of CFU-GM were reached on day +10 (9.2-fold for bag vs. 12-fold for flask), and (c) maximal expansion of CD15+/CD11b- population occurred on day +10 (517.5-fold for bag vs. 2959.2-fold for flask). So, we did not find any advantages by culturing further than day +10. We subsequently investigated the use of serum-free medium. The study showed better results when we used medium supplemented with autologous plasma versus serum-free system. In summary, these data described a strategy of culture clinically feasible and safe, using gas-permeable bags, and the kinetics and differentiation of neutrophils and neutrophil precursors from selected CD34+ cells in liquid cultures. Ex vivo expansion of this population might result in earlier engraftment as compared with that for selected stem cells alone.  相似文献   
998.
999.
Dietary fibers are widely used in hypoglycaemic, hypolipidemic, slimming diets. It is probable that their ingestion coincides with the oral administration of drugs and a modification of their pharmacokinetics can appear. In the present study, the influence of two soluble fibers (guar gum and psyllium) was evaluated on the pharmacokinetics of ethinyloestradiol (EE) when they were administered together to female rabbits via the oral route. Three groups of rabbits were used. All animals received 1 mg/kg of EE; this compound was administered alone in the control group and with 3.5 g of guar gum or psyllium in the other two groups. When guar gum was administered, there was a decrease in the extent of EE absorbed, but no change was observed in the rate of absorption. When psyllium was administered, the extent of EE absorbed increased slightly and the rate of absorption was slower.  相似文献   
1000.
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