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81.
Comparison of ViraPap, Southern hybridization, and polymerase chain reaction methods for human papillomavirus identification in an epidemiological investigation of cervical cancer. 总被引:3,自引:0,他引:3
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E Guerrero R W Daniel F X Bosch X Castellsagu N Muoz M Gili P Viladiu C Navarro M L Zubiri N Ascunce et al. 《Journal of clinical microbiology》1992,30(11):2951-2959
In order to provide a reliable diagnosis for the presence and type of human papillomavirus (HPV) DNA in a case-control study of cervical cancer in Colombia and Spain, 926 cervical scrapes from female subjects were examined by ViraPap (VP) and Southern hybridization (SH), and 510 of these (263 cases and 247 controls) were also tested by polymerase chain reaction (PCR) using the HPV L1 consensus primers. HPV DNA prevalence was much higher in cases than in controls by each of the three tests. There was complete agreement between the results of the three tests for 64.9% of the 510 specimens; 53.5% were negative and 11.4% were positive (regardless of type) by all tests. An additional 29.0% of the specimens were positive by PCR: 19.4% by PCR alone, 6.7% by PCR and VP, and 2.9% by PCR and SH. SH and/or VP gave positive results for 6.0% of the specimens for which the PCR finding was negative: 2.7% by SH alone, 2.5% by VP alone, and 0.8% by both VP and SH. When specimens which were positive by VP alone or only by SH at low-stringency conditions were excluded, PCR confirmed all but four specimens which were positive by other tests. The concordance between type-specific diagnosis by SH and PCR was 86% when HPVs were typed in both tests. HPV-16 accounted for over 80% of the typed HPVs in each test. The presence of blood in case specimens did not appear to inhibit HPV positivity by VP or by PCR at the dilution tested. Low amounts of cellular DNA of specimens resulted in some underestimation of HPV positivity by VP and SH but not by PCR. Compared with that of PCR, the sensitivities for case specimens were 38% by SH and 50% by VP; the sensitivity for control specimens, although it could not be measured precisely because there were few positive specimens, appeared to be lower than for case specimens. It was concluded that PCR-based tests are best suited for epidemiological investigation of HPVs. 相似文献
82.
83.
Morphological studies have shown that macrophages and microglia undergo
apoptosis in the central nervous system (CNS) in acute experimental
autoimmune encephalomyelitis (EAE) in the Lewis rat. To assess the relative
levels of macrophage and microglial apoptosis, and the molecular mechanisms
involved in this process, we used three-colour flow cytometry to identify
CD45lowCD11b/c+ microglial cells and CD45highCD11b/c+ macrophages in the
inflammatory cells isolated from the spinal cords of Lewis rats 13 days
after immunization with myelin basic protein (MBP) and complete Freund's
adjuvant. Simultaneously, we analyzed the DNA content of these cell
populations to assess the proportions of cells undergoing apoptosis and in
different stages of the cell cycle or examined their expression of three
apoptosis- regulating proteins, i.e. Fas (CD95), Fas ligand (FasL) and
Bcl-2. Microglia were highly vulnerable to apoptosis and were
over-represented in the apoptotic population. Macrophages were less
susceptible to apoptosis than microglia and underwent mitosis more
frequently than microglia. The different susceptibilities of microglia and
macrophages to apoptosis did not appear to be due to variations in Fas,
FasL or Bcl- 2 expression, as the proportions of microglia and macrophages
expressing these proteins were similar, and were relatively high.
Furthermore, in contrast to T cell apoptosis, apoptosis of
microglia/macrophages did not occur more frequently in cells expressing Fas
or FasL, or less frequently in cells expressing Bcl-2. These results
indicate that the apoptosis of microglia and CNS macrophages in EAE is not
mediated through the Fas pathway, and that Bcl-2 expression does not
protect them from apoptosis. Expression of FasL by macrophages and
microglia may contribute to the pathogenesis and immunoregulation of EAE
through interactions with Fas+ oligodendrocytes and Fas+ T cells. The high
level of microglial apoptosis in EAE indicates that microglial apoptosis
may be an important homeostatic mechanism for controlling the number of
microglia in the CNS following microglial activation and proliferation.
相似文献
84.
The role of size, sequence and haplotype in the stability of FRAXA and FRAXE alleles during transmission 总被引:2,自引:5,他引:2
Murray A; Macpherson JN; Pound MC; Sharrock A; Youings SA; Dennis NR; McKechnie N; Linehan P; Morton NE; Jacobs PA 《Human molecular genetics》1997,6(2):173-184
Factors involved in the stability of trinucleotide repeats during
transmission were studied in 139 families in which a full mutation,
premutation or intermediate allele at either FRAXA or FRAXE was
segregating. The transmission of alleles at FRAXA, FRAXE and four
microsatellite loci were recorded for all individuals. Instability within
the minimal and common ranges (0-40 repeats for FRAXA, 0-30 repeats for
FRAXE) was extremely rare; only one example was observed, an increased in
size at FRAXA from 29 to 39 repeats. Four FRAXA and three FRAXE alleles in
the intermediate range (41-60) repeats for FRAXA, 31-60 for FRAXE) were
unstably transmitted. Instability was more frequent for FRAXA intermediate
alleles that had a tract of pure CGG greater than 37 although instability
only occurred in two of 13 such transmissions: the changes observed were
limited to only one or two repeats. Premutation FRAXA alleles over 100
repeats expanded to a full mutation during female transmission in 100% of
cases, in agreement with other published series. There was no clear
correlation between haplotype and probability of expansion of FRAXA
premutations. Instability at FRAXA or FRAXE was more often observed in
conjunction with a second instability at an independent locus suggesting
genomic instability as a possible mechanism by which at least some FRAXA
and FRAXE mutations arise.
相似文献
85.
V Navarro 《The Milbank quarterly》1987,65(1):81-111
Since 1980 there has been an unprecedented shift in federal expenditures away from health and social welfare; an "electoral mandate" to reduce government's role is widely cited as justification. Yet, a survey of all major opinion polls of the past decade shows that electoral behavior and popular opinion are not synonymous. In exploring the historical ideological roots of this disjunction, the post- New Deal rise of "interest group" over "class" behavior is noted; "depoliticization" of political issues and "abstentionism" in voting follow. Rather than a realignment, recent elections represent a dealignment from regressive choices. 相似文献
86.
V Navarro 《Int J Health Serv》1984,14(2):321-328
This article analyzes four major assumptions that guide the Reagan Administration's health policies: 1) the Administration received an overwhelming popular mandate to reduce the federal role in the U.S. health sector; 2) the size and growth of federal social (including health) expenditures are contributing to the current economic recession; 3) the costs to business of federally imposed health and safety regulations have contributed to making the U.S. economy less competitive; and 4) market intervention is intrinsically more efficient than government intervention in regulating the costs and distribution of health resources. Based on these assumptions, the main characteristics of the Reagan Administration's health policies have been 1) a reduction of federal health expenditures and, very much in particular, expenditures to the poor, handicapped, and elderly; 2) a weakening of federal health and safety regulations to protect workers, consumers, and the environment; and 3) the further privatization and commodification of medical services. This article shows that there is no evidence to support the assumptions on which these policies are based. Quite to the contrary, all available evidence shows the opposite: 1) the majority of Americans want an expansion of federal health expenditures and a strengthening of federal health regulation; 2) U.S. government expenditures and regulations are much more limited than those of other countries whose economies are performing more satisfactorily; and 3) those countries with larger government interventions have more efficient health care systems than the American one, where the "free market" forces are primarily responsible for the allocation of resources. Thus, major Reagan Administration health policies are based on myth rather than reality. 相似文献
87.
A critique of the ideological and political position of the Brandt Report and the Alma Ata Declaration 总被引:1,自引:0,他引:1
V Navarro 《Int J Health Serv》1984,14(2):159-172
This article analyzes the Willy Brandt Commission Report and the WHO Alma Ata Declaration within the socioeconomic and political context that determined them, and makes a critique of the ideological and political assumptions that both documents make. Through an assumedly apolitical and technological-administrative discourse, both documents reproduce the major positions upheld by the hegemonic development establishments of the Western world. Through a study of what is being said and not said, the article analyzes how these positions appear in the documents. It is indicated that 1) their understanding of the causes of underdevelopment and its major health and disease problems, and 2) their suggestions for change based on "moral calls for social justice" and "enlightened self-interest" are faulty and insufficient. Alternative explanations and solutions are presented. 相似文献
88.
Ana Beln Navarro Prados Sara Jimnez García-Tizn Juan Carlos Melndez 《Health & social care in the community》2022,30(1):244-252
Care staff in nursing homes work in a challenging environment, and the COVID-19 pandemic has exacerbated those challenges in an unprecedented way. On the other hand, the sense of coherence (SOC) is a competence that could help these professionals perceive the situation as understandable, manageable and meaningful. This study aims to analyse the extent to which potential risk and protective factors against burnout have affected nursing home workers during the COVID-19 pandemic and to assess the contribution of these factors to their burnout. Three hundred forty professionals who worked in nursing homes in Spain completed a survey and reported on their sociodemographic characteristics and their organisational characteristics of the job related to COVID-19, SOC and burnout. Multiple linear regression analyses were performed. The results showed that the SOC is highly related to the dimensions of burnout and is a protective factor against this. In addition, the increase in hours has a negative effect, facilitating inadequate responses to stressful situations; and whereas perceived social support and availability of resources have a protective effect, the deterioration in mental and physical health is the most important risk factor. This study could help better understand the psychological consequences of the effort that nursing home workers and can also help design mental health prevention and care interventions for workers that provide them with resources and supports that foster their coping skills. 相似文献
89.
90.
Barroso Rosmeire Aparecida Navarro Ricardo Tim Carla Roberta de Paula Ramos Lucas de Oliveira Luciane Dias Araki Ângela Toshie Fernandes Karina Gonzales Camara Macedo Daniela Assis Lívia 《Lasers in medical science》2021,36(6):1235-1240
Lasers in Medical Science - Acne vulgaris is the most recurring skin condition in the world, causing great harm to the physical and psychological well-being of many patients. Antimicrobial... 相似文献