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761.
Herpes zoster, immunological deterioration and disease progression in HIV-1 infection 总被引:1,自引:0,他引:1
J Veenstra A Krol RM van Praag PH Frissen PT Schellekens JM Lange RA Coutinho JT van der Meer 《Canadian Metallurgical Quarterly》1995,9(10):1153-1158
OBJECTIVE: To study the incidence of herpes zoster, the relationship between herpes zoster and immunological markers, and the prognostic value of herpes zoster for progression of HIV disease. DESIGN AND METHODS: A total of 966 homosexual participants in The Amsterdam Cohort Study were studied. Herpes zoster was defined by its characteristic clinical presentation. Incidence was calculated using Poisson regression, cumulative incidence by the Kaplan-Meier product-limit method and the prognostic value was evaluated using Cox proportional hazards model. RESULTS: The incidence of first episodes of herpes zoster was 3.31 per 1000 person-years (PY) in HIV-seronegatives and 51.51 per 1000 PY in HIV-1-seropositive individuals. Recurrences only occurred in HIV-1-positive patients (25.6%). Cumulative incidences of first episodes increased linearly with the duration of follow-up. In HIV-1-seropositives the incidence was 31.2 per 1000 PY at CD4+ cells > or = 500 x 10(6)/l, 47.2 per 1000 PY [relative risk (RR), 1.51; 95% confidence interval (CI), 0.78-2.94] at CD4+ cells 200-499 x 10(6)/l and 97.5 per 1000 PY (RR, 3.13; 95% CI, 1.54-6.32) at CD4+ cells < 200 x 10(6)/l. Besides CD4+ cell counts, CD3 monoclonal antibodies and phytohaemagglutinin-induced T-cell reactivity were independent predictors for herpes zoster. The hazard ratio for AIDS after herpes zoster was 1.6 (95% CI, 1.1-2.4) and for death 1.7 (95% CI, 1.1-2.5), but these were not independent from CD4+ cell counts. CONCLUSION: In HIV-1 infection the incidence of herpes zoster increases with the decrease of CD4+ cell counts and T-cell reactivity, but herpes zoster is not an independent predictor for disease progression. 相似文献
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763.
A recombinant baculovirus containing a cDNA clone encoding the nucleocapsid (NP) protein of Newcastle disease virus (strain Ulster 2C) has been used to infect insect cells (Spodoptera frugiperda). High levels of overexpressed NP protein were observed, comprising up to 40% of total cellular protein, which were subsequently shown to be antigenic. Nucleoprotein derived from the crude soluble lysate of infected insect cells has been used in an indirect ELISA to detect the presence of anti-NDV antibodies in a cohort of chicken sera. Data produced from these tests indicated a good correlation between ELISA titre and haemagglutination inhibition test data. The test was not affected by interference from background cellular proteins nor by cross-reactivity with non-NDV poultry pathogens. Additionally, the test did not generate false-positive readings. 相似文献
764.
765.
Repeated vital capacity (VC) breaths in 17 anesthetized and curarized dogs induced a small but significant increase in residual volume (RV). This trapping was greatly enhanced when a mixture of 80% N2O and 20% O2 (N2O-O2) was used instead of air. VC breaths with N2O-O2 also increased closing volume, closing capacity and closing pressure determined with 133Xe. Successive quasi-static pressure volume (PV) curves of the lung showed a shift to the right at high lung volume and to the left at low lung volume. Again these changes were more impressive with N2O-O2). The PV curve of the chest wall was unchanged. Insufflations from RV were necessary to produce the gas trapping. Increase in RV was positively related to the size of the inspired volume, to N2O concentration, and inversely related to the inspiratory flow rate. Vagotomy, intravenous isoproterenol, and intravenous propanolol did not alter the phenomena. We propose that these observations can be explained by the presence of foam in the airways and that N2O leads to an increase of foam by osmotic liquid shift into the bronchioli, and/or to an increase in bubble's size by gas diffusion. 相似文献
766.
767.
768.
The degree of polarization of light reflected from a transparent or translucent object depends only upon the angle of incidence, refractive index and absorption coefficient of the material. It is therefore possible to determine the orientation of the surface normal from the direction of the plane of polarization. The feasibility of this is demonstrated both theoretically and practically by calculating and measuring the reflectance map of a sphere when viewed through a plane polarizing filter. Ambiguities in the mapping from radiance to orientation are removed by orienting the filter at three angles. The orientation of our objects is determined to within an uncertainty of less than seven degrees. 相似文献
769.
Johan Ninan Stewart Clegg Ashwin Mahalingam 《International Journal of Project Management》2019,37(1):59-72
This paper explores subtle strategies that megaproject teams develop in practice to manage stakeholders external to the project team. A governmentality approach is used to account for these strategies. A metro rail megaproject in India provides the case for the study. The strategies were identified through a content analysis of 640 project and non-project based Tweets posted by the metro rail organization. We augmented this dataset with the community's response through social media, as well as through semi-structured interviews that captured the project teams' responses. The findings indicate that the megaproject used various strategies: promoting the organization, giving progress updates, appealing to the community, as well as targeting of specific sections of the population. The effect of these attempts at governmentality through branding were observed in community discourses on social media platforms that echoed the strategic discourses projected by the megaproject while interviews enabled us to access the project team's responses. For the project community, the effects included a positive brand image, creating community brand advocates and building support for the project during contentious episodes. For the project team, the effects included job attraction, enhanced job perception as well as the creation of project team brand advocates. The relation between the governmentality instruments and their corresponding effects are theorized in six propositions. 相似文献
770.
HR Andersen JC Nielsen PE Thomsen L Thuesen T Vesterlund AK Pedersen PT Mortensen 《Canadian Metallurgical Quarterly》1998,98(13):1315-1321
BACKGROUND: It has been claimed that patients with sick sinus syndrome have an increased risk of developing AV block, but this has never been assessed prospectively. The aim of the present study was to evaluate in a prospective trial AV conduction during the long-term follow-up of patients with sick sinus syndrome. METHODS: Two hundred twenty-five consecutive patients with sick sinus syndrome and intact AV conduction were randomized to undergo single-chamber atrial pacing (110 patients) or single-chamber ventricular pacing (115 patients). Follow-up after 3 months and then yearly included measurement of the PQ interval and, in patients with atrial pacemakers, determination of the atrial stimulus-Q intervals at pacing rates of 100 and 120 bpm. The occurrence of AV block in the atrial group was recorded. During follow-up (mean, 5.5+/-2.4 years), there was no change in PQ interval in either group and no change in atrial stimulus-Q intervals or Wenckebach block point in the atrial group. Four of 110 patients in the atrial group developed grade 2 to 3 AV block that required upgrading of the pacemaker (0.6% per year). Two of these 4 patients had right bundle-branch block at pacemaker implantation. CONCLUSIONS: AV conduction, estimated as PQ interval and atrial stimulus-Q interval at atrial pacing rates of 100 and 120 bpm and the Wenckebach block point, remains stable during long-term follow-up. Thus, treatment with single-chamber atrial pacing is safe and can be recommended to patients with sick sinus syndrome without bundle-branch block. 相似文献