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排序方式: 共有1545条查询结果,搜索用时 15 毫秒
1.
Gregers Mads Christian Tofte Mikkelsen Søren Lindvig Katrine Prier Brøchner Anne Craveiro 《Neurocritical care》2020,33(1):273-282
Neurocritical Care - For years, the use of ketamine as an anesthetic to patients suffering from acute brain injury has been debated because of its possible deleterious effects on the cerebral... 相似文献
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A method is suggested and described which allows to introduce areas of different sizes, shapes, sites, and doses into a photon irradiation field. The bases for calculation and manufacturing of such irregular field stops containing integrated dose modification blocks are, according to precision requirements and data acquisition possibilities, either information provided by computed tomography or conventional planning radiographs. The following standard parameters are required as input data: sizes, shapes, and positions of the partial fields within the total irradiation field, depth of the reference plane, absorption coefficient of the modification material used, proportions of the planned dose modification, radiation quality, and other radiation field parameters. For the calculation of the dose distributions within the generally irregularly shaped irradiation volumes, an iterative algorithm has been formulated following the differential sector addition method and an equivalent TAR scheme. The quality of such a modifier can be checked by standard dosimetric methods. Deviations from the planned dose modification can be defined as sigma = +/- 5% for the radiation qualities employed (60Co gamma radiation and 15 MeV bremsstrahlung of a linear accelerator). 相似文献
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Mads Hald Andersen Rikke B Soerensen Jürgen C Becker Per thor Straten 《Journal of translational medicine》2006,4(1):38-4
Recently, it was described that an HLA-A24 restricted peptide derived from the survivin splice variant survivin-2B can be
recognized by CD8(+) cytotoxic T-cells. The identification of an HLA-A24 epitope is critical for survivin-based immunotherapy
as HLA-24 is the most frequent HLA allele in Asia. Consequently, this survivin-2B epitope is already a target in a clinical
study in patients with advanced or recurrent colorectal cancer expressing survivin. However, the splice variant survivin-2B
has been described to be pro-apoptotic, and is only expressed at low levels in most malignant tissues. Furthermore, survivin-2B
expression are significantly decreased in later tumor stages and inversely correlated with tumor differentiation and invasion.
Consequently, survivin is a more general vaccination candidate than the splice variant survivin-2B. Here, we on the basis
of spontaneous immune responses in HLA-A24+ cancer patients describes that a HLA-A24-restricted survivin epitopes does indeed
exist. Consequently, this epitope is an attractive target for the ongoing survivin-based peptide immunotherapy against cancer. 相似文献
5.
Neural classifier construction using regularization, pruning and test error estimation 总被引:1,自引:0,他引:1
Mads Hintz-Madsen Lars Kai Hansen Jan Larsen Morten With Pedersen Michael Larsen 《Neural networks》1998,11(9):1659-1670
In this paper we propose a method for construction of feed-forward neural classifiers based on regularization and adaptive architectures. Using a penalized maximum likelihood scheme, we derive a modified form of the entropic error measure and an algebraic estimate of the test error. In conjunction with optimal brain damage pruning, a test error estimate is used to select the network architecture. The scheme is evaluated on four classification problems. 相似文献
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The NTP has a long history of using Fischer rats and has compiled a large database of incidences of lesions seen in control animals. Such a database is lacking for Harlan Sprague-Dawley (SD) rats. The intention of this paper is to report spontaneous lesions observed in female vehicle control Harlan SD rats, and to compare the incidence in 2 strains of rats (Fischer and Harlan SD) used in NTP studies. Female Harlan SD rats served as the test animals for a special series of 2-year studies. Male rats were not used in these studies. Complete histopathology was performed on all animals, and the pathology results underwent comprehensive NTP pathology peer review. The most commonly observed neoplasms in these female control Harlan SD rats were mammary gland fibroadenoma (71%), tumors of the pars distalis of the pituitary (41%) and thyroid gland C-cell tumors (30%). Female Fischer rats had incidences of 44% for mammary gland fibroadenomas, 34% for tumors of the pars distalis, and 16% for thyroid gland C-cell tumors. Fischer rats had a 15% incidence of clitoral gland tumors, while the Harlan SD rats had an incidence of < 1%. In contrast to Fischer F344 rats, the Harlan SD rats had a high incidence of squamous metaplasia of the uterus (44.2%). Squamous metaplasia is not a lesion commonly observed in NTP control Fischer rats. The Harlan SD rats had a very low incidence of mononuclear cell leukemia (0.5%), compared with an incidence of 24% in female Fischer rats. 相似文献
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Brix S Kjaer TM Barkholt V Frøkiaer H 《International archives of allergy and immunology》2004,135(3):216-220
BACKGROUND: Microbial components in the environment are potent activators of the immune system with capacity to shift the active immune response towards priming of Th1 and/or Th2 cells. Lipopolysaccharide (LPS), a cell-wall component of Gram-negative bacteria, is extensively present in food products like cow's milk. It is not well established, however, how this presence of LPS affects oral tolerance induction. METHODS: We studied the effect of LPS contamination in a commercial preparation of the cow milk protein beta-lactoglobulin (beta-LG) on antigen-specific immune responses. IgG1/IgG2a production upon intraperitoneal immunization without adjuvant was measured, and oral tolerance induction against beta-LG after administration of either an aqueous solution or water-in-oil (w/o) emulsion of beta-LG was evaluated. RESULTS: LPS contamination of beta-LG provoked a beta-LG-specific IgG2a response, as well as an enhanced beta-LG-specific IgG1 response upon intraperitoneal immunization. Oral tolerance induction to beta-LG was induced by aqueous solutions of beta-LG with and without LPS administration. Conversely, oral administration of w/o-emulsified beta-LG prevented oral tolerance to beta-LG only when the beta-LG was contaminated with LPS. CONCLUSIONS: LPS contamination of an aqueous protein solution does not affect oral tolerance induction, whereas LPS present in emulsion prevents oral tolerance induction towards the food protein. 相似文献
10.
Mode of delivery and risk of allergic rhinitis and asthma 总被引:2,自引:0,他引:2
Bager P Melbye M Rostgaard K Benn CS Westergaard T 《The Journal of allergy and clinical immunology》2003,111(1):51-56
BACKGROUND: It has been hypothesized that cesarean section might increase the risk of developing allergic disease by depriving the fetus and newborn of exposure to maternal microflora. Furthermore, it has been suggested that complicated modes of delivery might be associated with an increased risk of asthma. OBJECTIVE: The purpose of this investigation was to study whether cesarean section and other complicated modes of delivery are associated with an increased risk of allergic rhinitis or asthma. METHODS: Information on self-reported allergic rhinitis, asthma ever, current asthma, and occupation was obtained from 9722 singleton women born in Denmark during the period 1973-1977 who participated in a national cohort study during the period 1997-2001. For these women, information was available on mode of delivery (spontaneous delivery, cesarean section, vacuum extraction, or other complicated mode of delivery, such as rotation/traction or use of forceps), gestational age, birth weight, and length at birth from the Danish Medical Birth Register. Information on parity and maternal age was obtained from the Danish Civil Registration System. RESULTS: The odds ratios (ORs) of allergic rhinitis were 1.16 (95% CI, 0.90-1.49) for cesarean section and 1.06 (95% CI, 0.85-1.32) for other complicated modes of delivery in comparison with spontaneous delivery. The corresponding ORs of asthma ever were 1.33 (95% CI, 1.02-1.74) and 1.18 (95% CI, 0.94-1.49) for cesarean section and other complicated modes of delivery, respectively, and the ORs of current asthma were 1.22 (95% CI, 0.87-1.73) and 1.26 (95% CI, 0.94-1.68), respectively, in comparison with spontaneous delivery. CONCLUSIONS: Our findings do not support the hypothesis that cesarean section or other complicated modes of delivery are associated with the development of allergic rhinitis. However, there might be a positive association with development of asthma--in particular, for cesarean section--that was not explained by gestational age, birth weight, ponderal index, smallness for gestational age, parity, maternal age, or occupation. 相似文献