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991.
Journal of Public Health - Adolescents’ sleep duration has decreased over the past century; this is mainly caused by problems with falling asleep. Short sleep duration, poor sleep quality,...  相似文献   
992.
Participant attitudes are an explanatory factor for attrition in online health-related interventions. However, its assessment prior to interventions start is uncommon, partly because proper measures are missing. This study presents the psychometric properties of a new scale measuring attitudes towards online psychoeducational interventions (OPIs). Structural validity, reliability and screening performance of the Online Psychoeducational Intervention – Brief Attitudes Scale (OPI-BAS) were studied in a sample of 157 dementia caregivers. Scale cut-off scores were derived to categorise the participants into ‘OPIs sympathisers’ or ‘non-sympathisers’. Groups were compared across sociodemographic and internet use variables. A parsimonious five-item version of OPI-BAS demonstrated good structural validity, with one factor explaining 63.3% of variance. Internal consistency of the scale was high (α = 0.85). OPI-BAS showed good screening performance in identifying individuals with either a preference to use conventional face-to-face or online psychoeducational interventions (area under the curve = 0.84). An optimal cut-off score of 20 was suggested by the receiver operating characteristic graph, providing good sensitivity (74%) and specificity (84%). No significant differences were found between groups on sociodemographic and internet use variables. Attitudes towards OPIs were overall positive, but face-to-face interventions were preferred. This study offers preliminary support to the psychometric quality of OPI-BAS. This short scale has practical applications for research and intervention.  相似文献   
993.
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   
994.
Vaccination of cats with fowlpox virus expressing the avian influenza (AI) virus H5 hemagglutinin gene (TROVAC AI) resulted in detectable hemagglutination inhibition (HI) antibody responses to the homologous A/Turkey/Ireland/1378/83 (H5N8) (A/tky/Ire/83) AI virus antigen. The HI antibody responses to heterologous A/Chicken/Indonesia/7/03 (H5N1) (A/ck/Indonesia/03) AI virus antigen were also detected in all vaccinated cats, but only after booster vaccinations. The vaccine described in this study and other poxvirus-vectored vaccines may be of value for the prophylaxis of AI virus-associated morbidity and mortality in mammals.  相似文献   
995.
Connectivity, the self-defined interactions between antigen-recognising molecules in a network system can in part be assessed by measuring the reactivity of a given serum against an ordered set of immunoglobulin (Ig)G F(ab')2 fractions, separated by means of isoelectric focusing so that, the serum reactivity against the whole set of fractions defines a characteristic pattern of connectivity. Deviations from the normal condition (healthy donors) have so far been documented for two autoimmune diseases: systemic lupus erythematosus (SLE) and pemphigus vulgaris, as well as for human immunodeficiency virus (HIV)-1 infection. We tested here if bacterial infections lead to alterations in connectivity. In addition, we wanted to test if two antigenically related bacteria would produce similar or otherwise distinctive connectivity patterns. Connectivity analysis was applied on the sera from tuberculosis and leprosy patients and the sera from healthy donors were used as control. No statistically significant differences between the three groups studied were found. These results have implications for theories that set the origin of autoimmune diseases in microbial infections. To the best of our knowledge, this is the first attempt to analyze the connectivity status in bacterial infections.  相似文献   
996.
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   
997.
The last few years have seen the development of several molecular designs to search for mutations encoding resistance to antituberculous drugs in Mycobacterium tuberculosis . Most of these are highly efficient for RIF-r detection and are well adapted to search for the most relevant INH-R mutations. In this review, these new molecular approaches are explained and are presented according to the molecular strategies on which they are based. In this sense, techniques based on DNA-sequencing, electrophoresis and hybridization are reviewed and the newer designs based on real-time PCR and microarrays are also included. Molecular methods are sure to transform standard approaches to the issue of resistance in the mycobacteriology laboratory. This will allow laboratories to speed up the performance of resistance assays and provide access to essential information for highly refined detection, follow-up and management of antibiotic resistance in M. tuberculosis .  相似文献   
998.
The interaction between the infectious bursal disease virus (IBDV) capsid proteins VP2 and VP3 has been analyzed in vivo using baculovirus expression vectors. Data presented here demonstrate that the 71-amino acid C-terminal-specific domain of pVP2, the VP2 precursor, is essential for the establishment of the VP2-VP3 interaction. Additionally, we show that coexpression of the pVP2 and VP3 polypeptides from independent genes results in the assembly of virus-like particles (VLPs). This observation demonstrates that these two polypeptides contain the minimal information required for capsid assembly, and that this process does not require the presence of the precursor polyprotein.  相似文献   
999.
Positive Force Feedback Control of Muscles   总被引:5,自引:0,他引:5  
  相似文献   
1000.
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