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21.
M Van Brussel M Salemi HF Liu J Gabri?ls P Goubau J Desmyter AM Vandamme 《Canadian Metallurgical Quarterly》1998,243(2):366-379
We have isolated a highly divergent simian T-lymphotropic virus, STLV-PP1664, from a wild-caught bonobo (Pan paniscus). Previous phylogenetic analysis suggested that this virus represents an additional type of STLV but this has now become a matter of discussion. We have now obtained and analyzed the entire genome of STLV-PP1664. All major genes and their corresponding viral messengers were identified. Sequence comparison and phylogenetic analysis indicated that this virus, together with the closely related panp isolate, belongs to an early lineage within the PTLV-2 clade, differing from HTLV-2 by about 25%. In contrast to the HTLV-1 and HTLV-2 LTR, only two 21-bp repeats instead of three were found in the STLV-PP1664 LTR. Additional messengers, resulting from alternative splicing, potentially encode five different accessory proteins from open reading frames in the pX region: prorfI, porfII, ptorfV', and two isoforms of Rex. The amino acid sequences of these proteins are only distinctly related to the accessory proteins from HTLV-2. These data suggest a different genomic organization of the STLV-PP1664 pX region than that of HTLV-2. We conclude that STLV-PP1664, although related to HTLV-2, has some distinct features in the LTR and the pX regions, the impact of which needs further investigation. Although arguments pro and contra a distinct classification are nearly equally balanced, we propose to classify this virus as an STLV-2, designated STLV-2PP1664. 相似文献
22.
Reversible phosphorylation on tyrosine residues is an extremely rapid and powerful posttranslational modification that is used in signalling pathways for the regulation of cell growth and differentiation. Over the past several years an impressive number of receptor-like protein tyrosine phosphatase (RPTPase) family members have been identified by molecular cloning, and undoubtedly many more will follow. This review provides an overview of the molecular data that are available for the currently identified RPTPases and discusses their possible biological implications. 相似文献
23.
Agreement in describing a chronic leg ulcer is pivotal in identifying and treating impediments to the healing process. Six nurses and one doctor without special experience with wound healing registered wound related diagnoses for a five month period. On average each patient was seen by three observers yielding 270 registrations. Agreement beyond chance (global kappa) showed poor to moderate agreement. Agreement was best for the yellow or malodorous wound and lowest for cellulitis, hypergranulation and peripheral pulses. This emphasizes the importance of allocating wound treatment to specialist departments with access to paraclinical investigations. 相似文献
24.
The most common chromosomal aberrations in myelodysplastic syndromes (MDS) are complete or partial loss of chromosomes 5 and 7, and trisomy 8. To identify genes important in the pathogenesis of this disease that could be associated with these gross chromosomal defects, we have employed the differential display PCR (DDPCR) procedure developed by Liang and Pardee. This method allows simultaneous comparison of several cDNA sources for the presence of differentially expressed genes. Polymorphonuclear cells (PMNs) from two MDS patients, containing a 5q deletion or a trisomy 8, and three healthy controls were used. Initial screening resulted in the identification of five and three partial cDNA sequences, respectively that were either differentially expressed in both patient samples or in individual patients, as compared with the controls. The authenticity of aberrant expression was verified by reanalyzing the same primer combinations on newly prepared cDNA. Differential expression of the three remaining fragments was subsequently checked on a larger panel of MDS patients, using amplicon-specific primer sets. These were obtained by cloning and sequencing of the fragments. For one partial cDNA (DC3), the original expression pattern, i.e., decreased expression in individual MDS patients, was confirmed. These results demonstrate the utility of the DDPCR procedure to isolate differentially expressed sequences in primary patient samples where the availability of cells is a limiting factor. 相似文献
25.
Hasan Celik Alan Hanjalic Emile A. Hendriks 《Computer Vision and Image Understanding》2009,113(10):1076-1094
Object detection is an essential component in automated vision-based surveillance systems. In general, object detectors are constructed using training examples obtained from large annotated data sets. The inevitable limitations of typical training data sets make such supervised methods unsuitable for building generic surveillance systems applicable to a wide variety of scenes and camera setups. In our previous work we proposed an unsupervised method for learning and detecting the dominant object class in a general dynamic scene observed by a static camera. In this paper, we investigate the possibilities to expand the applicability of this method to the problem of multiple dominant object classes. We propose an idea on how to approach this expansion, and perform an evaluation of this idea using two representative surveillance video sequences. 相似文献
26.
A historic overview including the European, American, Asian, and African continents is given on attitudes toward and the handling of humans with congenital malformations in ancient cultures and on pertinent customs in some prehistoric peoples. Figures of early works of art showing malformed individuals are presented testifying to this worldwide and timeless problem of humankind. In parallel, analogous patient photographs from our hospital before and after reconstructive surgery are shown. Philosophies of ancient Greece, rome, and China on the subject of malformed infants essentially did not differ from the known attitudes of the less developed tribes in Europe and pre-Columbian America, although the means of elimination of unwanted offspring were rather passive (exposure) than active (manual killing). A radical change in attitudes and practices occurred with the spread of the Christian religion and its political installment in Europe. The care for the underprivileged including the malformed ones was considered a Christian duty to be performed with compassion and love. In our century, the clocks have been and apparently are turned back again. Atheistic and Darwinian influences, political atheism, and the belief in "higher ethics" issued by "superman" have led to a relapse into barbarism, also within the medical system. We, as craniofacial surgeons, are privileged to have the means to turn the clocks forward again by rehabilitating the physically most underprivileged: those with conspicuous craniofacial malformations. The necessary techniques exist and are applied, as the figures of patients from our hospital demonstrate, but the will and the emotional strength for their consequent application require more than our hands. 相似文献
27.
The advent of pixelated detectors for time‐of‐flight neutron transmission experiments has raised significant interest in terms of the potential for tomographic reconstructions of triaxial strain distributions. A recent publication by Lionheart and Withers [WRB Lionheart and PJ Withers, “Diffraction tomography of strain”, Inverse Problems, v31:045005, 2015] has demonstrated that reconstruction is not possible in the general sense; however, various special cases may exist. In this paper, we outline a process by which it is possible to tomographically reconstruct average triaxial elastic strains within individual particles in a granular assembly from a series of Bragg edge strain measurements. This algorithm is tested on simulated data in two and three dimensions and is shown to be capable of rejecting Gaussian measurement noise. Sources of systematic error that may present problems in an experimental implementation are briefly discussed. 相似文献
28.
Hendriks Martijn Verriet Jacques Basten Twan Theelen Bart Brassé Marco Somers Lou 《International Journal on Software Tools for Technology Transfer (STTT)》2017,19(4):487-510
International Journal on Software Tools for Technology Transfer - System designers make trade-offs between metrics of interest such as execution time, functional quality and cost to create a... 相似文献
29.
Observational studies of sitting have shown that, during spontaneous sitting, people adopt a variety of postures. Various researchers have formulated theories to explain why people adopt their sitting postures. Branton (1969) hypothesized that there is continual need for postural stability while sitting. Dempster (1955) stated that additional stability could be obtained through temporarily closing chains of body segments, or, in other words, through decreasing the number of degrees of freedom of the body. The present study elaborates on Dempster's theory. The aim of this study was to determine the influence of the degrees of freedom of the body on postural stability in sitting postures. For 21 different sitting postures, the total number of degrees of freedom was determined. Postural sway, a measure for postural stability, was determined using a 3D motion and position measurement system with ten healthy subjects. This study shows that the mean path length at the level of the second thoracic vertebra (PL0.05), a measure derived from postural sway, increases significantly (p < 0.0001) with an increase of the number of degrees of freedom of the body (DoFB). Closer examination of the data showed that a model taking into account only the degrees of freedom of the lumbar and thoracic spine and pelvis seems to be a better predictor of postural sway than the total number of degrees of freedom of the body. 相似文献
30.
HF Jeejeebhoy 《Canadian Metallurgical Quarterly》1977,35(2):161-169
Lymphocytes from 10 patients with breast carcinoma were seeded in autologous serum, on autochthonous tumour cells and allogeneic tissue-cultured breast tumour cell lines. In 4 patients, the anti-tumour cell cytotoxicity against at least one of 3 breast tumour cell lines differed significantly from that against autochthonous tumour cells. Further study of these 4 individuals (using their previously frozen lymphoid cells and sera) showed that these differences occurred because serum which decreased ("blocked") lymphocyte anti-tumour cytotoxicity when applied to one tumour cell line, could either have no effect or potentiate it when applied to another, without any consistent pattern vis-à-vis target-cell susceptibility to these different humoral effects. 相似文献