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21.
On the residual water content of dried but viable cells 总被引:1,自引:0,他引:1
J. S. Clegg A. C. Zettlemoyer H. H. Hsing 《Cellular and molecular life sciences : CMLS》1978,34(6):734-735
Summary We have examined the residual water in dried cysts of the brine shrimp,Artemia salina, by gas-bombardment techniques at reduced pressures and temperatures. This treatment reduced, but did not remove all the residual water, the lower limit being about 0.0069 gH2O/g dried weight. The significance of such small amounts of water to cell hydration is assessed. The treatment did not appreciably reduce the viability of this cyst population.Supported in part by grant PCM-24037 from the US National Science Foundation. 相似文献
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Cheung VG Nowak N Jang W Kirsch IR Zhao S Chen XN Furey TS Kim UJ Kuo WL Olivier M Conroy J Kasprzyk A Massa H Yonescu R Sait S Thoreen C Snijders A Lemyre E Bailey JA Bruzel A Burrill WD Clegg SM Collins S Dhami P Friedman C Han CS Herrick S Lee J Ligon AH Lowry S Morley M Narasimhan S Osoegawa K Peng Z Plajzer-Frick I Quade BJ Scott D Sirotkin K Thorpe AA Gray JW Hudson J Pinkel D Ried T Rowen L Shen-Ong GL Strausberg RL Birney E Callen DF Cheng JF Cox DR Doggett NA Carter NP Eichler EE 《Nature》2001,409(6822):953-958
We have placed 7,600 cytogenetically defined landmarks on the draft sequence of the human genome to help with the characterization of genes altered by gross chromosomal aberrations that cause human disease. The landmarks are large-insert clones mapped to chromosome bands by fluorescence in situ hybridization. Each clone contains a sequence tag that is positioned on the genomic sequence. This genome-wide set of sequence-anchored clones allows structural and functional analyses of the genome. This resource represents the first comprehensive integration of cytogenetic, radiation hybrid, linkage and sequence maps of the human genome; provides an independent validation of the sequence map and framework for contig order and orientation; surveys the genome for large-scale duplications, which are likely to require special attention during sequence assembly; and allows a stringent assessment of sequence differences between the dark and light bands of chromosomes. It also provides insight into large-scale chromatin structure and the evolution of chromosomes and gene families and will accelerate our understanding of the molecular bases of human disease and cancer. 相似文献
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Mungall AJ Palmer SA Sims SK Edwards CA Ashurst JL Wilming L Jones MC Horton R Hunt SE Scott CE Gilbert JG Clamp ME Bethel G Milne S Ainscough R Almeida JP Ambrose KD Andrews TD Ashwell RI Babbage AK Bagguley CL Bailey J Banerjee R Barker DJ Barlow KF Bates K Beare DM Beasley H Beasley O Bird CP Blakey S Bray-Allen S Brook J Brown AJ Brown JY Burford DC Burrill W Burton J Carder C Carter NP Chapman JC Clark SY Clark G Clee CM Clegg S Cobley V Collier RE Collins JE Colman LK Corby NR Coville GJ 《Nature》2003,425(6960):805-811
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As in other competitive sports, the famous Grand National steeplechase, which is held at Aintree in the United Kingdom and is watched by 600 million people worldwide, sometimes results in injury. By analysing data from the past 15 Grand National races (consisting of 560 starts by horses), we are able to identify several factors that are significantly associated with failure to complete the race: no previous experience of the course and its unique obstacles, unfavourable ground conditions (too soft or too hard), a large number of runners, and the length of the odds ('starting price'). We also find that there is an increased risk of falling at the first fence and at the jump known as Becher's Brook, which has a ditch on the landing side. Our findings indicate ways in which the Grand National could be made safer for horses and illustrate how epidemiological analysis might contribute to preventing injury in competitive sport. 相似文献
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TACI and BCMA are receptors for a TNF homologue implicated in B-cell autoimmune disease 总被引:120,自引:0,他引:120
Gross JA Johnston J Mudri S Enselman R Dillon SR Madden K Xu W Parrish-Novak J Foster D Lofton-Day C Moore M Littau A Grossman A Haugen H Foley K Blumberg H Harrison K Kindsvogel W Clegg CH 《Nature》2000,404(6781):995-999
B cells are important in the development of autoimmune disorders by mechanisms involving dysregulated polyclonal B-cell activation, production of pathogenic antibodies, and co-stimulation of autoreactive T cells. zTNF4 (BLyS, BAFF, TALL-1, THANK) is a member of the tumour necrosis factor (TNF) ligand family that is a potent co-activator of B cells in vitro and in vivo. Here we identify two receptors for zTNF4 and demonstrate a relationship between zTNF4 and autoimmune disease. Transgenic animals overexpressing zTNF4 in lymphoid cells develop symptoms characteristic of systemic lupus erythaematosus (SLE) and expand a rare population of splenic B-Ia lymphocytes. In addition, circulating zTNF4 is more abundant in NZBWF1 and MRL-lpr/lpr mice during the onset and progression of SLE. We have identified two TNF receptor family members, TACI and BCMA, that bind zTNF4. Treatment of NZBWF1 mice with soluble TACI-Ig fusion protein inhibits the development of proteinuria and prolongs survival of the animals. These findings demonstrate the involvement of zTNF4 and its receptors in the development of SLE and identify TACI-Ig as a promising treatment of autoimmune disease in humans. 相似文献
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A novel alpha-globin gene arrangement in man 总被引:22,自引:0,他引:22
The human genome has two linked alpha-globin genes on chromosome 16. Deletion of one or more of them, as occurs in alpha-thalassaemia, leads to a reduced output of alpha-globin mRNA in proportion to the number of alpha-globin genes lost. In some racial groups deletion of one of the pair of alpha-globin genes may result from unequal crossing over between the genes on homologous chromosomes by a mechanism resembling that postulated for the formation of the delta beta fusion genes of the Lepore haemoglobins. By analogy, the opposite chromosome in this cross-over should have three alpha-globin genes just as the 'anti-Lepore chromosome has three non-alpha chain genes. We describe here a Welsh family in which three members have five alpha-globn increased alpha mRNA output and it may therefore produce the phenotype of mild beta-thalassaemia. 相似文献
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Interleukin 21 and its receptor are involved in NK cell expansion and regulation of lymphocyte function 总被引:64,自引:0,他引:64
Parrish-Novak J Dillon SR Nelson A Hammond A Sprecher C Gross JA Johnston J Madden K Xu W West J Schrader S Burkhead S Heipel M Brandt C Kuijper JL Kramer J Conklin D Presnell SR Berry J Shiota F Bort S Hambly K Mudri S Clegg C Moore M Grant FJ Lofton-Day C Gilbert T Rayond F Ching A Yao L Smith D Webster P Whitmore T Maurer M Kaushansky K Holly RD Foster D 《Nature》2000,408(6808):57-63
Cytokines are important in the regulation of haematopoiesis and immune responses, and can influence lymphocyte development. Here we have identified a class I cytokine receptor that is selectively expressed in lymphoid tissues and is capable of signal transduction. The full-length receptor was expressed in BaF3 cells, which created a functional assay for ligand detection and cloning. Conditioned media from activated human CD3+ T cells supported proliferation of the assay cell line. We constructed a complementary DNA expression library from activated human CD3+ T cells, and identified a cytokine with a four-helix-bundle structure using functional cloning. This cytokine is most closely related to IL2 and IL15, and has been designated IL21 with the receptor designated IL21 R. In vitro assays suggest that IL21 has a role in the proliferation and maturation of natural killer (NK) cell populations from bone marrow, in the proliferation of mature B-cell populations co-stimulated with anti-CD40, and in the proliferation of T cells co-stimulated with anti-CD3. 相似文献
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