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991.
Anabel Moriña 《Health & social care in the community》2021,29(5):1559-1565
When research involves people, ethics are fundamental. In the health and social sciences, when qualitative methodologies are used, in addition to ensuring an ethical process approved by the ethics review board, it is also necessary to guarantee an ethical practice capable of responding adequately to the complex questions and dilemmas which arise as the study progresses. This theoretical article analyses some of the most sensitive issues involved in qualitative research and discusses the following questions: (a) How should ethics be approached when working with vulnerable groups? (b) Is informed consent enough? (c) Should we rethink anonymity? (d) What is the difference between confidentiality and anonymity? (e) What exactly do we mean by relational ethics? (f) How can we avoid hurting people, yet remain honest? In the conclusions, we discuss some basic aspects for ensuring ethical studies. This paper, therefore, may be of interest to all health and social researchers concerned about ensuring that their studies comply with ethical principles which recognise, protect and respect participants’ rights. 相似文献
992.
Salcedo M Taja L Utrera D Chávez P Hidalgo A Pérez C Benítez L Castañeda C Delgado R Gariglio P 《International journal of experimental pathology》2002,83(6):275-286
The role of tumour suppressor genes in the development of human cancers has been studied extensively. In viral carcinogenesis, the inactivation of suppressor proteins such as retinoblastoma (pRb) and p53, and cellular oncogenes overexpression, such as c-myc, has been the subject of a number of investigations. In uterine-cervix carcinomas, where high-risk human papillomavirus (HPV) plays an important role, pRb and p53 are inactivated by E7 and E6 viral oncoproteins, respectively. However, little is known about the in situ expression of some of these proteins in pre-malignant and malignant cervical tissues. On the other hand, it has also been demonstrated that c-myc is involved in cervical carcinogenesis, and that pRb participates in the control of c-myc gene expression. By using immunostaining techniques, we investigated pRb immunodetection pattern in normal tissues, squamous intraepithelial lesions (SILs) and invasive carcinomas from the uterine cervix. Our data show low pRb detection in both normal cervical tissue and invasive lesions, but a higher expression in SILs. C-Myc protein was observed in most of the cellular nuclei of the invasive lesions, while in SILs was low. These findings indicate a heterogeneous pRb immunostaining during the different stages of cervical carcinogenesis, and suggest that this staining pattern could be a common feature implicated in the pathogenesis of uterine-cervix carcinoma. 相似文献
993.
994.
A novel methodology for characterization of animal sperm shape involving the use of a spectral approach to multiscale curvature estimation is proposed. By using the derivative property of the Fourier transform, allied to Gaussian smoothing, accurate estimates of the curvature along the sperm contour can be obtained in such a way that the curvature peaks corresponding to the sperm head vertices can be effectively identified. The measurements derived from such a processing, namely the width of the basal region of the head, the centralization of tail implantation, and the multiscale bending energy, provide valuable resources for fertility and phylogenetic studies. 相似文献
995.
Transplantation of embryonic Raphe cells regulates the modifications of the gabaergic phenotype occurring in the injured spinal cord 总被引:3,自引:0,他引:3
Transection of the spinal cord yields a permanent deficit due to the interruption of descending and ascending tracts which subserve the supraspinal control of spinal cord functions. We have shown previously that transplantation below the level of the section of embryonic monoaminergic neurons can promote the recovery of some segmental functions via a local serotonergic and noradrenergic reinnervation. Moreover, the up-regulation of the corresponding receptors resulting from the section was corrected by the transplants. The aim of the present work was to determine whether such a graft could also influence non-monoaminergic local neurons, the GABAergic interneurons of the spinal cord. Following spinal cord transection, the number of cells which express glutamate decarboxylase (mol. wt 67,000) messenger RNA--a marker of GABA synthesis--increased significantly below the lesion compared with the intact animal. In contrast, in lesioned animals which had been grafted one week later with raphe neuroblasts, this number was close to control level. These post-grafting modifications were further associated with increased GABA immunoreactivity in the host tissue. These data suggest that the graft of embryonic raphe cells which compensates the deficit of serotonin in the distal segment also regulates the expression of the GABAergic phenotype in the host spinal cord. This regulation could be mediated by the re-establishment of a local functional innervation by both serotonin and GABAergic transplanted neurons and/or by trophic factors released from the embryonic cells. It appears then that grafted cells influence the host tissue in a complex manner, through the release and/or regulation of several neurotransmitter systems. 相似文献
996.
Alvarez JI Londoño DP Alvarez AL Trujillo J Jaramillo MM Restrepo BI 《Journal of comparative pathology》2002,127(2-3):186-193
Taenia solium cysticerci infect human beings and pigs, causing cysticercosis. In this study the pig was used as a model to characterize the immune response against cysticerci, given the difficulties in analysing the developing immune response in infected human brains. Metacestodes in different stages of viability or degeneration were isolated from the brain, heart and skeletal muscle of naturally infected swine, and the adjacent tissue was examined histologically. The immune response elicited by the cysticerci was classified into four separate stages. In stage I the parasites were surrounded by a thin layer of collagen type I, and by stage II there was a sparse inflammatory infiltrate. In stage III, granuloma formation was evident, and by stage IV the parasite was surrounded by an eosinophil-rich infiltrate and its vesicular membrane had begun to degenerate. The final stage, IV, was detected mainly in the heart but not in the brain. The granulomatous reaction in swine resembled that described previously in human patients, but differed in the abundance of eosinophils, the relative paucity of plasma cells, and the discrete deposition of collagen. These differences were probably due to the fact that in pigs the immune response can be examined earlier than in human patients, in whom sampling is inevitably made at a more chronic stage. 相似文献
997.
Nocardia ignorata, a new agent of human nocardiosis isolated from respiratory specimens in Europe and soil samples from Kuwait 下载免费PDF全文
Rodríguez-Nava V Couble A Khan ZU Pérouse de Montclos M Brasme L Villuendas C Molinard C Boiron P Laurent F 《Journal of clinical microbiology》2005,43(12):6167-6170
Nocardia ignorata is a recently described species identified on the basis of a single isolate of unknown origin. Here we describe the epidemiological, phenotypic, and phylogenetic characteristics of this new species, based on five new clinical and soil isolates. 相似文献
998.
P. Lylyk F. Viñuela H. V. Vinters J. Dion J. Bentson G. Duckwiler T. Lin 《Neuroradiology》1990,32(4):304-310
Summary The internal carotid artery system in swine has a special anatomic configuration similar to a brain arterial-arterial malformation. The internal carotid artery breaks up into a multitude of fine channels (rete mirabile) situated at the base of the skull on the side of the hypophysis. This anatomic arterial model was used to analyze acute and chronic angiographic and histological changes after occlusion of the rete mirabile with I) avitene, II) avitene, and 50% ethanol, III) avitene, 30% ethanol and Polyvinyl alcohol, IV) avitene 50% ethanol and Polyvinyl alcohol, V) IBCA and VI) silk. Histopathological changes observed in the rete mirabile six weeks following occlusion demonstrated that a mixture of avitene, 30% ethanol and Polyvinyl alcohol and IBCA produced the best anatomic results. Embolization with avitene, PVA and ethanol induced a more bland histological reaction than the one observed with IBCA. Preliminary clinical experience with this mixture is reassuring in those cases in which the AVM was surgically resected. The partially thrombosed AVM was easily depressed and compressed by the neurosurgeon allowing for satisfactory hemostasis in and around the nidus of the AVM.This paper was presented in part at the International Symposium on Cerebral Stroke, Sendai, Japan, 1987 相似文献
999.
J Espinar-Sierra M A Toledano C Franco J Campos-Castello M González-Hidalgo F Oliete M García-Nart 《Clinical neurophysiology》1990,20(1):35-42
Thirteen girls with Rett's syndrome were evaluated with wakefulness and sleep polygraphic records and EMG studies. The main EEG findings were paroxysmal activity during sleep, multifocal in younger and unifocal in older girls, and "pseudorhythmic flattening". In the opinion of the authors, the changes with age are related to evolution of the disease or maturational changes of CNS. The affectation of the peripheral nervous system was demonstrated in almost half the patients. 相似文献
1000.
M G Díaz-Barriga G Jackson-Herrerías 《ADM; revista de la Asociación Dental Mexicana》1990,47(3):128-132
In this paper a comparison of sedation effectiveness, vomiting incidence and postoperative sleeping time with three sedation schemes: Chloral hydrate exclusively, hidroxicine chlorhydrate the night before and 15 minutes before chloral hydrate administration and hidroxicine chlorhydrate 15 minutes before chloral hydrate. We find that there is no significant differences between these three sedation schemes in sedation, degree of postoperative sleeping time and vomiting incidence, therefore we can expect an effective sedation degree using any of these sedation methods. 相似文献