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31.
Roest RW Carman WF Maertzdorf J Scoular A Harvey J Kant M Van Der Meijden WI Verjans GM Osterhaus AD 《Journal of medical virology》2004,73(4):601-604
Clinical recurrences of Herpes simplex virus type 1 (HSV-1)-associated genital herpes are thought to be caused by reactivation of latent endogenous HSV-1. However, the possibility of reinfection with exogenous HSV-1 cannot be excluded. This study aimed to determine the incidence of genital HSV-1 superinfection in patients by investigating the genotype of sequential HSV-1 isolates obtained from the same anatomical site of patients with clinical recurrences of genital HSV-1 recurrent genital herpes. Sequential genital HSV-1 isolates were genotyped by PCR amplification of the hypervariable regions located within the HSV-1 genes US1 and US12. Whereas the sequential HSV-1 isolates in 11 of the 13 patients studied had the same genotypes, the sequential isolates of 2 patients showed a different genotype. The data suggest that HSV-1-induced recurrent genital herpes can be associated with genital reinfection with an exogenous HSV-1 strain. 相似文献
32.
Gastrointestinal stromal tumors (GISTs)--the Lebanese experience 总被引:1,自引:0,他引:1
Salamoun W El Hajj G Aftimos G Moukharbel N Khairallah S Bejjani N Abou Sleiman CH Abou Atmeh J Azar H Elias E Abi Gerges D 《Molecular immunology》2003,39(17-18):1129-1132
33.
34.
Chryssi Foroglou et Georges Winckler 《Anatomy and embryology》1973,140(1):19-37
Summary The ultrastructure of the muscle spindles has been studied in human lumbrical muscles. The findings have been compared with the morphology of muscle spindles of rat and sheep examined with light and electron microscopy. The study is based on cross and longitudinal sections of the entire muscle spindle obtained by dissection. The different components of the spindle are described with special reference to the nuclear bag and nuclear chain fibres. These nuclei have been examined in human adult and newborn material and compared to the animal ones. ADN measurements revealed that although there are morphological differences between the two kinds of nuclei in human newborn spindles, the amount of ADN is the same as well in the nuclear bag as in the nuclear chain nuclei. Special attention is also given to the sensory and motor endings in the muscle spindles and to the presence of Pacinian corpuscules in these receptors. Finally two kinds of leptomeric organelles are described in human material. 相似文献
35.
Goujon D Zellweger M Radu A Grosjean P Weber BC van den Bergh H Monnier P Wagnières G 《Journal of biomedical optics》2003,8(1):17-25
The changes in the autofluorescence characteristics of the bronchial tissue is of crucial interest as a cancer diagnostic tool. Evidence exists that this native fluorescence or autofluorescence of bronchial tissues changes when they turn dysplastic and to carcinoma in situ. There is good agreement that the lesions display a decrease of autofluorescence in the green region of the spectrum under illumination with violet-light, and a relative increase in the red region of the spectrum is often reported. Imaging devices rely on this principle to detect early cancerous lesions in the bronchi. Based on a spectroscopic study, an industrial imaging prototype is developed to detect early cancerous lesions in collaboration with the firm Richard Wolf Endoskope GmbH, Germany. A preliminary clinical trial involving 20 patients with this spectrally optimized system shows that the autofluorescence can help to detect most lesions that would otherwise have remained invisible to an experienced endoscopist under white light illumination. A systematic off line analysis of the autofluorescence images pointed out that real-time decisional functions can be defined to reduce the number of false positive results. Using this method, a positive predictive value (PPV) of 75% is reached using autofluorescence only. Moreover, a PPV of 100% is obtained, when combining the white light (WL) mode and the autofluorescence (AF) mode, at the applied conditions. Furthermore, the sensitivity is estimated to be twice higher in the AF mode than in WL mode. 相似文献
36.
Cytosine methylation was studied at the level of the euchromatin/heterochromatin transition genomic region of the Arabidopsis chromosome 5 left arm. It has been shown using a monoclonal antibody against 5-methylcytosines that the density of DNA methylation
increases from the euchromatin towards the heterochromatin. YACs mapped along this region were characterized for their repeated
sequences content. Some of them, corresponding to euchromatin, euchromatin/heterochromatin border and heterochromatin regions,
were used as probes for a Southern blot analysis of methylation. This revealed that the degree of mCmCGG and GATmC methylation
increases significantly from the euchromatin towards the heterochromatin. Moreover, an analysis of cytosine methylation levels
(% of 5-methylcytosine) of different DNA fragments, inside the same genomic region, was performed using PCR and/or Southern
blot approaches. There is a gradual increase of methylation along the genomic region analyzed: CpG methylation in the euchromatic
fraction, CpG and CpNpG methylation at the euchromatin/heterochromatin transition and an additional asymmetrical methylation
in the repeated-heterochromatic fraction. The most methylated repeated family at CpG, CpNpG and asymmetrical sites is the
5S ribosomal DNA, highly methylated even though it is transcribed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
37.
38.
THE POTENTIAL USES OF GENOTYPING OF PLASMODIUMFALCIPARUMISOLATESBYTHENESTEDPOLYMERASECHAINREACTION 总被引:1,自引:0,他引:1
巢式PCR方法被应用于泰国疟区(Borai)恶性疟原虫的基因分型。应用特异的等位基因引物扩增了恶性疟原虫裂殖子表面蛋白1(MSP1)基因的1、4变异多态区。以凝胶电泳分析扩增的目的基因片段。结果表明:共分别检测出恶性疟原虫6个MAD20等位基因型、4个K1和1个RO33等位基因型。在9个月的流行季节,上述虫株的等位基因频率没有明显的改变,关存在较高程度的恶性疟原虫不同等位基因株的混合感染。本文进一步阐明了巢式PCR技术在疟疾流行病学上的应用前景及优点。 相似文献
39.
Sylvie De Kossodo Brigitte Critico Georges E. Grau 《European journal of immunology》1994,24(3):769-772
We investigated the effects of a single bacterial lipopolysaccharide (LPS) injection in vivo on the gene expression of tumor necrosis factor-α (TNF) and its receptors: TNF receptor type I (TNF-R 55 kDa or TNF-R1) and TNF receptor type II (TNF-R 75 kDa or TNF-R2) in various tissues and white blood cells. While TNF mRNA rapidly accumulated in most tissues, TNF-R1 and TNF-R2 mRNA levels were found to be differentially regulated in lung, spleen, lymph nodes and white blood cells. In most cases, TNF-R mRNA levels did not parallel TNF mRNA levels. These observations indicate that TNF-R of both types are capable of modulating the host response to LPS, not only by shedding of their extracellular domains, but also by strict regulation of their gene expression. 相似文献
40.
We have compared the use of two (93 and 185 keV) and three (93, 185, and 300 keV) photopeaks for Ga-67 tumor imaging and optimized the placement of each energy window. METHODS: The bases for optimization and evaluation were ideal and Bayesian signal-to-noise ratios (SNR) for the detection of spheres embedded in a realistic anthropomorphic digital torso phantom and ideal SNR for the estimation of their size and activity concentration. Seven spheres of radii ranging from 1 to 3 cm, located at several sites in the torso, were simulated using a realistic Monte Carlo program. We also calculated the ideal SNR for the detection from simple phantom acquisitions. RESULTS: For detection and estimation tasks, the optimum windows were identical for all sphere sizes and locations. For the 93 keV photopeak, the optimal window was 84-102 keV for the detection and 87-102 keV for estimation; these windows are narrower than the 20% window often used in the clinic (83-101 keV). For the 185 keV photopeak, the optimal window was 170-220 keV for the detection and 170-215 keV for estimation; these are substantially different than the 15% window used in our clinic (171-199 keV). For the 300 keV photopeak, the optimal window for detection was 270-320 keV, and for estimation, 280-320 keV. Using the three optimized, rather than only the two lower-energy, windows yielded a 9% increase in the SNR for the detection of the 3 cm diam sphere (a 12% increase for a 2 cm diam sphere) and a 7% increase in the SNR for estimation of its size. For the acquired phantom data, detection also increased by 9%-12% when using three, rather than two, energy windows. 相似文献