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61.
62.
Dr. Corine Layet Terry Delovitch Pierre Ferrier Danielle H. Caillol Bertrand R. Jordan François A. Lemonnier 《Immunogenetics》1985,21(5):469-478
Radioimmunoassay of HLA-transformed mouse L cells expressing A3, A24, B7, or Cw3 HLA class I molecules with a set of monomorphic monoclonal antibodies distinguishes between A3–A24 and B7-Cw3 patterns of reactivity. Analyses with Bw6-specific monoclonal antibodies and a human alloantiserum demonstrate the expression by the HLA-Cw3 molecules of a Bw6 public specificity related to but not identical with that expressed by the HLA-B7 molecules. Exon-shuffling experiments and inhibition studies of monoclonal antibody cell-surface fixation indicate that similar parts of B7 and Cw3 molecules account for their serological cross-reactivity.Abbreviations used in this paper
2-m
beta-2 microglobulin
- EBV
Epstein-Barr virus
- mAb
monoclonal antibody
- PBS-BSA
phosphate-buffered saline supplemented with 0.2% bovine serum albumin
- PBL
peripheral blood lymphocyte
- RIA
radioimmunoassay 相似文献
63.
Depth‐based differentiation in nitrogen uptake between graminoids and shrubs in an Arctic tundra plant community
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Peng Wang Juul Limpens Ake Nauta Corine van Huissteden Sophie Quirina van Rijssel Liesje Mommer Hans de Kroon Trofim C. Maximov Monique M.P.D. Heijmans 《植被学杂志》2018,29(1):34-41
Questions
The rapid climate warming in tundra ecosystems can increase nutrient availability in the soil, which may initiate shifts in vegetation composition. The direction in which the vegetation shifts will co‐determine whether Arctic warming is mitigated or accelerated, making the understanding of successional trajectories urgent. One of the key factors influencing the competitive relationships between plant species is their access to nutrients, depending on the depth where they take up most nutrients. However, nutrient uptake at different soil depths by tundra plant species that differ in rooting depth is unclear.Location
Kytalyk Nature Reserve, northeast Siberia, Russia.Methods
We injected 15N to 5 cm, 15 cm and the thaw front of the soil in a moist tussock tundra. The absorption of 15N by grasses, sedges, deciduous shrubs and evergreen shrubs from the three depths was compared.Results
The results clearly show a vertical differentiation of N uptake by these plant functional types, corresponding to their rooting strategy. Shallow‐rooting dwarf shrubs were more capable of absorbing nutrients from the upper soil than from deeper soil. Deep‐rooting grasses and sedges were more capable of absorbing nutrients from deeper soil than the dwarf shrubs. The natural 15N abundances in control plants also indicate that graminoids can absorb more nutrients from the deeper soil than dwarf shrubs.Conclusions
Our results show that graminoids and shrubs in the Arctic differ in their N uptake strategies, with graminoids profiting from nutrients released at the thaw front, while shrubs mainly forage in upper soil layers. Our results suggest that tundra vegetation will become graminoid‐dominated as permafrost thaw progresses and nutrient availability increases in the deep soil. 相似文献64.
Performance and diacetyl production of commercial strains of malolactic bacteria in wine 总被引:3,自引:2,他引:1
This study compares 11 commercial cultures of Leuconostoc oenos and Lactobacillus plantarum in Cabernet Sauvignon, Pinot Noir and Chardonnay wines. Performance of the cultures was found to be greatly influenced by wine type. Better survival of the bacteria was observed in Cabernet Sauvignon and Pinot Noir wines. The time necessary to complete malolactic fermentation (MLF) was 65 ± 14 d for Chardonnay, 71 ± 3 d for Cabernet Sauvignon, and 25 ± 8 d for Pinot Noir. The maximal rate of malate utilization was 0·4 g d-1 for Pinot Noir, and 0·2 g d-1 for the two other wine types. Final diacetyl concentration was lower in Chardonnay wines (highest 0·58 mg l-1 ) compared to the other wines (highest 5·8 mg l-1 ). Malic and citric acid were co-metabolized by all strains. None of the strains metabolized glycerol. Significant differences in final diacetyl concentration of wine vinified with the different strains were found. Panelists could reliably differentiate MLF wines from non-MLF wines, irrespective of their diacetyl content, indicating that diacetyl is not the only important MLF flavour. 相似文献
65.
A new subfamily of KH-domain-containing RNA-binding proteins is encoded by genes that are conserved from yeast to humans. Mutations with interesting developmental phenotypes have been identified in Caemorbabditis elegans, Drosophila and mouse. It is hypothesized that these bifunctional proteins provide a rich source of interesting molecular information about development and define a new cellular pathway that links signal transduction directly to RNA metabolism. 相似文献
66.
67.
Steffie K. Naber Suzette M. Matthijsse Kirsten Rozemeijer Corine Penning Inge M. C. M. de Kok Marjolein van Ballegooijen 《PloS one》2016,11(1)
Background
Vaccination against the oncogenic human papillomavirus (HPV) types 16 and 18 will reduce the prevalence of these types, thereby also reducing cervical cancer risk in unvaccinated women. This (measurable) herd effect will be limited at first, but is expected to increase over time. At a certain herd immunity level, tailoring screening to vaccination status may no longer be worth the additional effort. Moreover, uniform screening may be the only viable option. We therefore investigated at what level of herd immunity it is cost-effective to also reduce screening intensity in unvaccinated women.Methods
We used the MISCAN-Cervix model to determine the optimal screening strategy for a pre-vaccination population and for vaccinated women (~80% decreased risk), assuming a willingness-to-pay of €50,000 per quality-adjusted life year gained. We considered HPV testing, cytology testing and co-testing and varied the start age of screening, the screening interval and the number of lifetime screens. We then calculated the incremental cost-effectiveness ratio (ICER) of screening unvaccinated women with the strategy optimized to the pre-vaccination population as compared to with the strategy optimized to vaccinated women, assuming different herd immunity levels.Results
Primary HPV screening with cytology triage was the optimal strategy, with 8 lifetime screens for the pre-vaccination population and 3 for vaccinated women. The ICER of screening unvaccinated women 8 times instead of 3 was €28,085 in the absence of herd immunity. At around 50% herd immunity, the ICER reached €50,000.Conclusion
From a herd immunity level of 50% onwards, screening intensity based on the pre-vaccination risk level becomes cost-ineffective for unvaccinated women. Reducing the screening intensity of uniform screening may then be considered. 相似文献68.
69.
Régis Sodoyer Brigitte Kahn-Perles Torn Strachan Joséphine Sire Marie-José Santoni Corine Layet Pierre Ferrier Bertrand R. Jordan Francois A. Lemonnier 《Immunogenetics》1986,23(4):246-251
The individual contributions of the first two external domains of the HLA-B7 heavy chain to the expression of allele-specific (B7) and locus-specific (B and C) antigenic determinants were investigated using hybrid class I genes. Hybrid genes were constructed in vitro by exon shuffling between the parent genes HLA-B7, HLA-Cw3, HLA-A3, and H-2K
d, and their expression was monitored following transfection into mouse L cells. The results show that most allele-specific antigenic determinants are associated with the first external domain of the 137 heavy chain, whereas all the locus-specific antigenic determinants tested map to the second external domain.Abbreviations used in this paper BSA
bovine serum albumin
- FCS
fetal calf serum
- mAb
monoclonal antibody
- PBL
peripheral blood lymphocytes
- PBS
phosphate-buffered saline 相似文献
70.
At Ste. Justine Hospital, Montreal, during the period 1957-61, ECHO 9 virus was isolated in 27 cases, in 20 of these during the summer of 1961. All had evidence of meningeal irritation, accompanied by fever and headache. Four of the 20 patients diagnosed during the summer of 1961 had convulsions; 12 presented with a rash; and two simulated meningococcemia. Of the 27 patients, two were paralyzed and one case was diagnosed as transverse myelitis. ECHO 9 virus was isolated from stools and from throat specimens in equal proportion; it was isolated from cerebrospinal fluid in only two instances. Pathogenicity for suckling mice was observed in two of 22 inoculated directly with the specimen material and in 10 of 11 inoculated with the cultured material. 相似文献