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排序方式: 共有618条查询结果,搜索用时 46 毫秒
1.
Talita da Silva Mendes de Farias Ariclécio Cunha de Oliveira Sandra Andreotti Fernanda Gaspar do Amaral Patrícia Chimin André Ricardo Alves de Proença Francisco Leonardo Torres Leal Rogério Antonio Laurato Sertié Amanda Baron Campana Andressa Bolsoni Lopes Arnaldo Henrique de Souza José Cipolla‐Neto Fabio Bessa Lima 《Journal of pineal research》2015,58(3):251-261
Melatonin, the main hormone produced by the pineal gland, is secreted in a circadian manner (24‐hr period), and its oscillation influences several circadian biological rhythms, such as the regulation of clock genes expression (chronobiotic effect) and the modulation of several endocrine functions in peripheral tissues. Assuming that the circadian synchronization of clock genes can play a role in the regulation of energy metabolism and it is influenced by melatonin, our study was designed to assess possible alterations as a consequence of melatonin absence on the circadian expression of clock genes in the epididymal adipose tissue of male Wistar rats and the possible metabolic repercussions to this tissue. Our data show that pinealectomy indeed has impacts on molecular events: it abolishes the daily pattern of the expression of Clock, Per2, and Cry1 clock genes and Pparγ expression, significantly increases the amplitude of daily expression of Rev‐erbα, and affects the pattern of and impairs adipokine production, leading to a decrease in leptin levels. However, regarding some metabolic aspects of adipocyte functions, such as its ability to synthesize triacylglycerols from glucose along 24 hr, was not compromised by pinealectomy, although the daily profile of the lipogenic enzymes expression (ATP‐citrate lyase, malic enzyme, fatty acid synthase, and glucose‐6‐phosphate dehydrogenase) was abolished in pinealectomized animals. 相似文献
2.
In this research the histological characteristics of the macrophages on the colonic mucosa in Crohn's disease and ulcerative colitis were quantified and analysed. Twelve Crohn's disease, 19 ulcerative colitis and 10 specimen of the rectal mucosa, representing the control group according to the followed model, were studied: I period (PI) = pre-treatment, II period (PII) = up two years of evolution and III period (PIII) = more than two years of evolution. The macrophages were identified in a colonic mucosa by the monoclonal CD68 through the immunoperoxidase method. The macrophages quantification was done by chromatic computer images analysis, that express the area (mm2) used by the CD68 positive cells, in percentage. The percentage of the area used by the macrophages was increased in both diseases, in all the studied periods, when compared with the control group, but without statistic significance. The macrophages' distribution inside the control group mucosa was subepithelial, while in the illness group, it reached all the mucosa that was concentrated on the basis of ulcers and all long the fissures. On the Crohn's disease the CD68 positive cells facilited the identification of the microgranulomas, sometimes unnoticed in the hematoxiline-eosine. Although there was no difference between patients and control group in the macrophages area, the difference in the distribution could suggest the macrophages' participation on the injure in both diseases although they do not permit a differential diagnosis because of the variety of the values. The CD68 did not identify the different functional status of the macrophages, but their position in the mucosa suggest that, in terms of fissures and ulcers, their mainly function should be the phagocitosis and in the other cases, they have been the cells that should show the antigens and that recruit the other inflammatory cells. 相似文献
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5.
Chemiluminescence dot blot hybridization assay for detection of B19 parvovirus DNA in human sera. 总被引:5,自引:3,他引:2
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M Musiani M Zerbini D Gibellini G Gentilomi S Venturoli G Gallinella E Ferri S Girotti 《Journal of clinical microbiology》1991,29(9):2047-2050
A chemiluminescence dot blot hybridization assay was used for the detection of B19 parvovirus DNA in human sera by using digoxigenin-labeled probes. The probes were revealed immunoenzymatically by use of anti-digoxigenin Fab fragments conjugated with alkaline phosphatase. The chemiluminescence signal was obtained by reacting the labeled probe-target complex with an enzyme-triggerable dioxetane substrate. The emitted photons were detected with instant photographic films. In the search for B19 parvovirus DNA, 2,808 serum samples were analyzed. 相似文献
6.
Rapid detection of antibodies against cytomegalovirus induced immediate early and early antigens by an enzyme linked immunosorbent assay 总被引:3,自引:1,他引:3
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An enzyme linked immunosorbent assay (ELISA) for detecting antibodies against cytomegalovirus induced immediate early antigens and early antigens was developed using purified nuclear antigens and was compared with the indirect immunofluorescence test. The tests were comparable in their ability to detect positive and negative sera, and antibody titres determined by both assays were similar. The use of ELISA for the detection of antibodies against cytomegalovirus induced immediate early and early antigens is advocated in diagnostic and research laboratories. 相似文献
7.
Carlo Mancini Giulio Pisani Alberta Azzi Maria Luisa Zerbini Giuliano Gentili Guillermo Mario Bisso MS participants 《Journal of clinical virology》2004,30(4):313-319
BACKGROUND: The importance of the standardisation of nucleic acid amplification technology (NAT) assays for the detection of hepatitis C virus RNA is well known today, as many studies carried out in different European countries attest. The results of a previous study performed in Italy (J. Clin. Virol. 1 (2003) 83) by the Italian Society of Clinical Microbiology (AMCLI) showed that the use of external reference standards and of multicentre collaborative studies significantly improves laboratory performance for the qualitative evaluation of HCV RNA. OBJECTIVES: the AMCLI organised a new study on the standardisation of both the qualitative and the quantitative evaluation of HCV RNA with NAT in order to improve the implementation of the diagnostic methods for HCV RNA detection. STUDY DESIGN: seventeen diagnostic centres of major Italian Hospitals participated in this quality control study. The study consisted of testing three panels, each made up of 10 coded samples including negative and positive samples. Positive samples contained four levels of HCV RNA (genotype 1). RESULTS AND CONCLUSION: Seven out of 510 qualitative results obtained were incorrect (1.4%), two false negative and five false positive. The results gave a sensitivity of 99.5% and a specificity of 95.8%. Regarding quantitative tests, the geometric mean (GM) and standard deviation (S.D.) could be calculated only for the three highest HCV RNA levels. The percentage of results within the range of GM +/- 0.5 log(10) varied from 91% to 100%. Some laboratories had some difficulty in the exact quantification of the lowest (3.00 log IU/ml) as well as of the highest viral levels (6.35 log IU/ml) values, very near to the limits of the dynamic range of the assays. The comparison of the results of this study with that previously carried out one confirms that a regular participation in external quality assessment (EQA) assures the achievement of a high proficiency level in the diagnosis of HCV infection. 相似文献
8.
Distribution and viral load of type specific HPVs in different cervical lesions as detected by PCR-ELISA 总被引:8,自引:0,他引:8
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Zerbini M Venturoli S Cricca M Gallinella G De Simone P Costa S Santini D Musiani M 《Journal of clinical pathology》2001,54(5):377-380
AIMS: To investigate the distribution and viral load of the most prevalent high risk human papillomavirus (HPV) types 16, 18, 31, 33, and 45 and low risk HPV types 6 and 11 in a variety of cervical lesions. METHODS: One hundred and seventy six cytological specimens from women with different cervical lesions were investigated. For an accurate standardisation of the sample, cervical cells were counted and a volume of the cell suspension processed by polymerase chain reaction-enzyme linked immunosorbent assay (PCR-ELISA). Semiquantitative determinations were achieved in relation to an external reference titration curve. RESULTS: HPV DNA was detected in 60.2% of the samples. HPV-16 was the prevalent genotype (57.6%), followed by HPV-33, HPV-31, HPV-6, HPV-18, and HPV-45. HPV-11 was not detected. HPV-16 showed a pronounced increase in prevalence with the evolution of cervical disease. Semiquantitative evaluation of the results showed that only HPV-16 DNA could reach very high values (> 1000 genome copies/cell) and a very high HPV-16 load correlated with the severity of cervical disease. CONCLUSIONS: Only HPV-16 load appears to be associated with the severity of cervical disease. 相似文献
9.
Indirect alkaline phosphatase immunoenzymatic staining for the detection of antibodies to Epstein-Barr virus-induced virus capsid antigens and early antigens.
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An indirect alkaline phosphatase immunoenzymatic staining technique was developed for the detection of antibodies against Epstein-Barr virus-induced virus capsid antigens and early antigens in cell smears. The presence of antibodies against Epstein-Barr virus-induced virus capsid antigens and early antigens was revealed by a dark blue staining of cells expressing the antigens. The alkaline phosphatase assay gave a permanent record of the reaction that could be visualized under an ordinary light microscope. The titers obtained with this assay on 91 serum samples were significantly correlated with the titers obtained with an immunofluorescence technique. 相似文献
10.
Diagnostic procedures in B19 infection 总被引:15,自引:0,他引:15
In immunologic normal hosts, both children and adults, B19 can cause acute, generally self-limiting diseases. The infection leads to a viremia that can be present, at high titre, for about one week, then the onset of a specific immune response controls the infection. B19 infection in pregnancy can be associated with non-immunologic foetal hydrops or foetal death. In immunocompromised hosts, B19 can persist over several months and sometimes years. Persistent or recurrent B19 infections can be associated with chronic clinical manifestations or with transient clinical syndromes, generally related to the recrudescence of viral replication. Since the infection has been associated with a wide variety of clinical manifestations and some clinical features of B19 infection, such as anemia, artropathy and rash, can be common to other pathogens, a laboratory diagnosis of B19 infection is required. A diagnostic protocol must consider both the type of pathology and the type of patient. In immunocompetent individuals serological and virological testing is complementary, while in immunocompromised patients viral detection is the diagnosis of choice. Viral detection methods are generally based, nowadays, on the direct detection of B19 genome in clinical specimens. B19 DNA is mainly detected by hybridizations assays and by the most sensitive PCR assays. Serological diagnosis of B19 infection is generally achieved by detection of IgM and IgG antibodies to the B19 structural proteins VP1 and VP2. IgM detection is most often performed by capture assays, both in EIA and RIA formats, IgG are mainly detected by indirect EIA and immunofluorescence tests. 相似文献