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11.
Variations in human corneal endothelial cell morphology and permeability to fluorescein with age 总被引:1,自引:0,他引:1
Fluorophotometry with topically applied fluorescein and endothelial cell photography were performed on 80 normal subjects (age 5-79 yr). Variations in endothelial cell morphology and function, flow of aqueous humor, and intraocular pressure were recorded. The mean endothelial cell size was 332.3 +/- 46.3 micron 2. A 28% increase in endothelial cell size was measured over the eight decades (r = 0.53, P less than 0.001). The coefficient of variation of cell size also increased with age (r = 0.41, P less than 0.001). The percentage of hexagonal endothelial cells decreased by 14% (r = -0.48, P less than 0.001), while the percentage of pentagonal and heptagonal cells increased by 50% (r = 0.44, P less than 0.001) and 40% (r = 0.33, P less than 0.002), respectively, with age. The mean endothelial permeability to fluorescein was 4.03 +/- 0.63 x 10(-4) cm min-1. A 23% increase in endothelial permeability with age was observed (r = 0.44, P less than 0.001). No change in central corneal thickness or endothelial pump rate was found. Flow of aqueous humor remained stable with age, despite a 25% increase in intraocular pressure (r = 0.50, P less than 0.001). Polarization of fluorescence of fluorescein in the corneal stroma decreased with age (r = -0.46, P less than 0.001). We conclude that with age the human corneal endothelium becomes morphologically less regular and may become more permeable to fluorescein. 相似文献
12.
N McLaren 《The Australian and New Zealand journal of psychiatry》1992,26(2):270-276
As a process of rational enquiry into an empirical field, psychiatry must submit itself to the same discipline as other areas of science. Effectively, it must show that its fundamental premises are both internally and externally consistent, and that its methods of investigation satisfy prevailing criteria of scientific methodology. When psychoanalytic psychology (and hence all psychodynamic models) and behaviourism were analysed from these points of view, they were found wanting. To date, there has been little or no meta-analysis of the third great school of psychiatric theorizing, biological psychiatry. A preliminary analysis establishes sharp limits to the notion that biological psychiatry is the "wave of the future". Like psychoanalysis and behaviourism, it cannot form the basis of a general theory of psychiatry. Since it lacks an adequate theoretical framework, the inescapable conclusion is that psychiatry is nothing more than protoscience. 相似文献
13.
Ultrastructural observations on the in vitro interaction between rat eosinophils and some parasitic helminths (Schistosoma mansoni, Trichinella spiralis and Nippostrongylus brasiliensis). 总被引:20,自引:2,他引:20 下载免费PDF全文
D J McLaren C D Mackenzie F J Ramalho-Pinto 《Clinical and experimental immunology》1977,30(1):105-118
Rat eosinophils form an intimate association with the surfaces of parasitic helminths, in vitro, in the presence of immune serum. The parasite presents a non-phagocytosable surface to the cell. The initial response of the eosinophil is degranulation which leads to the formation of large cytoplasmic vacuoles. Peroxidase, an enzyme localized in the matrix of the crystalloid secretion granules, is discharged into these vacuoles as a consequence of degranulation. The vacuoles eventually become connected to the adherent basal plasma membrane of the eosinophil, and peroxidase is secreted directly onto the surface of the parasite. There is no morphological evidence to suggest that this particular secretion affects the integrity of the parasite surface. 相似文献
14.
Immunity to Influenza in Ferrets X. Intranasal Immunization of Ferrets with Inactivated Influenza A Virus Vaccines 下载免费PDF全文
The response of ferrets after intranasal inoculation of inactivated A/Hong Kong/68 (H3N2) influenza virus vaccines is reported. Normal ferrets given either saline vaccine in drops or freeze-dried vaccine in an aerosol intranasally did not produce detectable serum or nasal hemagglutination inhibiting antibody and were found to be completely susceptible to challenge infection with A/Hong Kong/68 virus. Intranasal saline vaccine did not produce an additive effect on the response of ferrets simultaneously given the same vaccine intramuscularly with adjuvant. Ferrets primed by previous infection with A/PR/8/34 (H0N1) influenza virus, however, responded to intranasal immunization with saline A/Hong Kong/68 virus vaccine and produced serum and nasal antibody. These animals were found to be partially resistant to challenge infection, in contrast to similar animals given saline vaccine intramuscularly which were completely resistant to challenge infection. Primed ferrets did not respond after immunization with the freeze-dried aerosol vaccine, but this may have been due to a failure of the aerosol to be inhaled satisfactorily. 相似文献
15.
Defective interfering particles from poliovirus vaccine and vaccine reference strains 总被引:2,自引:0,他引:2
Defective interfering (DI) viral particles have been found to be associated with attenuated oral poliovirus vaccine and also with poliovirus vaccine reference strains. The DI particles replicate in low-passage human fibroblastic cells, the BSC-1 line of monkey kidney cells as well as in HeLa cells. DI particles of the attenuated polioviruses are generated after relatively few serial, high multiplicity passages of cloned, DI-free vaccine virus, whereas virulent strains of poliovirus generate a significant number of DI only after a large number of passages. 相似文献
16.
Mayne M Moffatt T Kong H McLaren PJ Fowke KR Becker KG Namaka M Schenck A Bardoni B Bernstein CN Melanson M 《European journal of immunology》2004,34(4):1217-1227
DNA microarray profiling of CD4(+) and CD8(+) cells from non-treated relapsing and remitting multiple sclerosis (MS) patients determined that the cytoplasmic binding partner of fragile X protein (CYFIP2, also called PIR121) was increased significantly compared to healthy controls. Western analysis confirmed that CYFIP2 protein was increased approximately fourfold in CD4(+) cells from MS compared to inflammatory bowel disorder (IBD) patients or healthy controls. Because CYFIP2 acts as part of a tetrameric complex that regulates WAVE1 activation we hypothesized that high levels of CYFIP2 facilitate T cell adhesion, which is elevated in MS patients. Several findings indicated that increased levels of CYFIP2 facilitated adhesion. First, adenoviral-mediated overexpression of CYFIP2 in Jurkat cells increased fibronectin-mediated adhesion. Secondly, CYFIP2 knock-down experiments using antisense oligodeoxynucleotides reduced fibronectin-mediated binding in Jurkat and CD4(+) cells. Thirdly, inhibition of Rac-1, a physical partner with CYFIP2 and regulator of WAVE1 activity, reduced fibronectin-mediated adhesion in Jurkat and CD4(+) cells. Finally, inhibition of Rac-1 or reduction of CYFIP2 protein decreased fibronectin-mediated adhesion in CD4(+) cells from MS patients to levels similar to controls. These studies suggest that overabundance of CYFIP2 protein facilitates increased adhesion properties of T cells from MS patients. 相似文献
17.
18.
Immunity to influenza in ferrets. I. Response to live and killed virus 总被引:14,自引:0,他引:14
19.
Home monitoring of blood pressure: usefulness as a predictor of persistent hypertension 总被引:1,自引:0,他引:1
We set out to test the hypothesis that home blood pressure reflects "baseline" pressures measured at a general practitioner's surgery or in a hospital outpatient clinic. Twenty patients detected hypertensive during screening in general practice and 30 patients referred to a hospital hypertension clinic for revision of therapy were studied. All were instructed in the use of an electronic semiautomatic sphygmomanometer and measured blood pressure at home for a three day period. Home monitored blood pressure correctly predicted those patients whose diastolic blood pressure fell to below 95 mmHg by the third clinic visit in approximately 90% of all patients. In addition, in those whose blood pressure was high at home it remained so at the clinic or surgery after three visits. These data suggest that home monitoring of blood pressure may be a helpful alternative to repeated clinic visits before embarking on medical therapy. 相似文献
20.
The personality structure of 65 volunteers for a Phase 1 drug trial was examined using the Eysenck Personality Questionnaire. It revealed a common pattern of high extroversion, low neuroticism and psychoticism. The reasons why the study might attract such people are examined and the structure compared with those that take drugs that might have 'strange or dangerous effects'. The likely forms of bias that this personality structure may bring to the trial are explored. 相似文献