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排序方式: 共有1923条查询结果,搜索用时 203 毫秒
1.
2.
Bacteriophage which produce either clear or turbid center plaques have been isolated for native isolates of Caryophanon latum. 相似文献
3.
Differential gene expression during mouse spermatogenesis 总被引:9,自引:0,他引:9
K H Thomas T M Wilkie P Tomashefsky A R Bellvé M I Simon 《Biology of reproduction》1989,41(4):729-739
4.
D Emilie C Wallon P Galanaud A Fischer D Olive J F Delfraissy 《Journal of immunology (Baltimore, Md. : 1950)》1988,141(6):1912-1918
We examined the role of the lymphocyte function-associated (LFA)3 molecule in human B cell response. A mAb to this molecule did not influence B cell proliferation induced by anti-mu antibody and IL. In contrast, the same mAb inhibited the specific T-dependent B cell response induced by a particulate Ag. In the same line, two anti-CD2 mAb (directed toward the T11-1 and T11-2 epitopes) inhibited this response, whether used alone or in association. These inhibitions took place at an early stage of the response, and anti-LFA3 and anti-CD2 mAb acted on B cells and T cells, respectively. In contrast, when T cell help was provided by exogenous IL-2, the B cell response was resistant to the inhibitory effect of anti-LFA3 mAb. Taken together, these results indicate that the LFA3-CD2 pair play a major role in the direct T-B interaction required for T cell help. 相似文献
5.
Stable length polymorphism of up to 260 kb at the tip of the short arm of human chromosome 16 总被引:34,自引:0,他引:34
A O Wilkie D R Higgs K A Rack V J Buckle N K Spurr N Fischel-Ghodsian I Ceccherini W R Brown P C Harris 《Cell》1991,64(3):595-606
We have completed a long-range restriction map of the terminal region of the short arm of human chromosome 16 (16p13.3) by physically linking a distal genetic locus (alpha-globin) with two recently isolated probes to telomere-associated repeats (TelBam3.4 and TelBam-11). Comparison of 47 chromosomes has revealed major polymorphic length variation in this region: we have identified three alleles in which the alpha-globin genes lie 170 kb, 350 kb, or 430 kb from the telemere. The two most common alleles contain different terminal segments, starting 145 kb distal to the alpha-globin genes. Beyond this boundary these alleles are nonhomologous, yet each contains sequences related to other (different) chromosome termini. This chromosome size polymorphism has probably arisen by occasional exchanges between the subtelomeric regions of nonhomologous chromosomes; analogous length variation is likely to be present at other human telomeres. 相似文献
6.
The contribution deals with the phytocenological analysis of theRondeletio correifoliae-Andropogonetum multinervosi, an endemic savanna association occuring on the Siguanea Hills (Sierra de la Siguanea) near the Colony Hotel. 相似文献
7.
Detection of cryptic chromosomal abnormalities in unexplained mental retardation: a general strategy using hypervariable subtelomeric DNA polymorphisms. 总被引:8,自引:0,他引:8 下载免费PDF全文
A O Wilkie 《American journal of human genetics》1993,53(3):688-701
Given the availability of DNA from both parents, unusual segregation of hypervariable DNA polymorphisms (HVPs) in the offspring may be attributable to deletion, unbalanced chromosomal translocation, or uniparental disomy. The telomeric regions of chromosomes are rich in both genes and hypervariable minisatellite sequences and may also be particularly prone to cryptic breakage events. Here I describe and analyze a general approach to the detection of subtelomeric abnormalities and uniparental disomy in patients with unexplained mental retardation. With 29 available polymorphic systems, approximately 50%-70% of these abnormalities could currently be detected. Development of subtelomeric HVPs physically localized with respect to their telomeres should provide a valuable resource in routine diagnostics. 相似文献
8.
De novo truncation of chromosome 16p and healing with (TTAGGG)n in the alpha-thalassemia/mental retardation syndrome (ATR-16). 总被引:12,自引:7,他引:5
J Lamb P C Harris A O Wilkie W G Wood J G Dauwerse D R Higgs 《American journal of human genetics》1993,52(4):668-676
We have previously described a series of patients in whom the deletion of 1-2 megabases (Mb) of DNA from the tip of the short arm of chromosome 16 (band 16p13.3) is associated with alpha-thalassemia/mental retardation syndrome (ATR-16). We now show that one of these patients has a de novo truncation of the terminal 2 Mb of chromosome 16p and that telomeric sequence (TTAGGG)n has been added at the site of breakage. This suggests that the chromosomal break, which is paternal in origin and which probably arose at meiosis, has been stabilized in vivo by the direct addition of the telomeric sequence. Sequence comparisons of this breakpoint with that of a previously described chromosomal truncation (alpha alpha)TI do not reveal extensive sequence homology. However, both breakpoints show minimal complementarity (3-4 bp) to the proposed RNA template of human telomerase at the site at which telomere repeats have been added. Unlike previously characterized individuals with ATR-16, the clinical features of this patient appear to be solely due to monosomy for the terminal portion of 16p13.3. The identification of further patients with "pure" monosomy for the tip of chromosome 16p will be important for defining the loci contributing to the phenotype of this syndrome. 相似文献
9.
Yitong Yao Philippe Ciais Nicolas Viovy Emilie Joetzjer Jerome Chave 《Global Change Biology》2023,29(3):747-762
During the last two decades, inventory data show that droughts have reduced biomass carbon sink of the Amazon forest by causing mortality to exceed growth. However, process-based models have struggled to include drought-induced responses of growth and mortality and have not been evaluated against plot data. A process-based model, ORCHIDEE-CAN-NHA, including forest demography with tree cohorts, plant hydraulic architecture and drought-induced tree mortality, was applied over Amazonia rainforests forced by gridded climate fields and rising CO2 from 1901 to 2019. The model reproduced the decelerating signal of net carbon sink and drought sensitivity of aboveground biomass (AGB) growth and mortality observed at forest plots across selected Amazon intact forests for 2005 and 2010. We predicted a larger mortality rate and a more negative sensitivity of the net carbon sink during the 2015/16 El Niño compared with the former droughts. 2015/16 was indeed the most severe drought since 1901 regarding both AGB loss and area experiencing a severe carbon loss. We found that even if climate change did increase mortality, elevated CO2 contributed to balance the biomass mortality, since CO2-induced stomatal closure reduces transpiration, thus, offsets increased transpiration from CO2-induced higher foliage area. 相似文献
10.
Laetitia Mathon Virginie Marques Stéphanie Manel Camille Albouy Marco Andrello Emilie Boulanger Julie Deter Régis Hocdé Fabien Leprieur Tom B. Letessier Nicolas Loiseau Eva Maire Alice Valentini Laurent Vigliola Florian Baletaud Sandra Bessudo Tony Dejean Nadia Faure Pierre-Edouard Guerin Meret Jucker Jean-Baptiste Juhel Kadarusman Andrea Polanco F. Laurent Pouyaud Dario Schwörer Kirsten F. Thompson Marc Troussellier Hagi Yulia Sugeha Laure Velez Xiaowei Zhang Wenjun Zhong Loïc Pellissier David Mouillot 《Global Ecology and Biogeography》2023,32(8):1336-1352