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51.
Cytokines affect a variety of cellular functions, including regulation of cell numbers by suppression of programmed cell death. Suppression of apoptosis requires receptor signalling through the activation of Janus kinases and the subsequent regulation of members of the B-cell lymphoma 2 (Bcl-2) family. Here we demonstrate that a Bcl-2-family-related protein, Hax1, is required to suppress apoptosis in lymphocytes and neurons. Suppression requires the interaction of Hax1 with the mitochondrial proteases Parl (presenilin-associated, rhomboid-like) and HtrA2 (high-temperature-regulated A2, also known as Omi). These interactions allow Hax1 to present HtrA2 to Parl, and thereby facilitates the processing of HtrA2 to the active protease localized in the mitochondrial intermembrane space. In mouse lymphocytes, the presence of processed HtrA2 prevents the accumulation of mitochondrial-outer-membrane-associated activated Bax, an event that initiates apoptosis. Together, the results identify a previously unknown sequence of interactions involving a Bcl-2-family-related protein and mitochondrial proteases in the ability to resist the induction of apoptosis when cytokines are limiting. 相似文献
52.
本实验创立了二种水产养殖池塘底泥总氮含量简易测定法,分别称为总氨法和硝酸盐法.通过与使用LECO公司的全自动CHN分析仪(Dumas仪器法)进行12个池塘底泥样品的测定结果比对,以及对所建立的回归方程经显著性检验,结果表明这两种方法均与Dumas仪器法之间存在线性相关,并回归极显著.二种土壤总氮含量的简易测定法,均实现了简化检测步骤、减少检测工作量、节省检测时间及降低成本,能满足许多水产技术推广站及养殖场等普通的实验室开展池塘底泥总氮含量的检测要求. 相似文献
53.
Lindström S Vachon CM Li J Varghese J Thompson D Warren R Brown J Leyland J Audley T Wareham NJ Loos RJ Paterson AD Rommens J Waggott D Martin LJ Scott CG Pankratz VS Hankinson SE Hazra A Hunter DJ Hopper JL Southey MC Chanock SJ Silva Idos S Liu J Eriksson L Couch FJ Stone J Apicella C Czene K Kraft P Hall P Easton DF Boyd NF Tamimi RM 《Nature genetics》2011,43(3):185-187
High-percent mammographic density adjusted for age and body mass index is one of the strongest risk factors for breast cancer. We conducted a meta analysis of five genome-wide association studies of percent mammographic density and report an association with rs10995190 in ZNF365 (combined P = 9.6 × 10(-10)). Common variants in ZNF365 have also recently been associated with susceptibility to breast cancer. 相似文献
54.
Cells of the anterior lobe of the bovine hypophysis, show an affinity for immunoglobulins IgG, IgA and IgM. The phenomenon either provides a message to stimulate cellular secretion or to excite mechanisms associated with the synthesis and release of Ig's or their determinants. 相似文献
55.
Cusumano G Mangano V Chincarini G Panaitescu A Burrows DN La Parola V Sakamoto T Campana S Mineo T Tagliaferri G Angelini L Barthelemy SD Beardmore AP Boyd PT Cominsky LR Gronwall C Fenimore EE Gehrels N Giommi P Goad M Hurley K Kennea JA Mason KO Marshall F Mészáros P Nousek JA Osborne JP Palmer DM Roming PW Wells A White NE Zhang B 《Nature》2006,440(7081):164
Long gamma-ray bursts (GRBs) are bright flashes of high-energy photons that can last for tens of minutes; they are generally associated with galaxies that have a high rate of star formation and probably arise from the collapsing cores of massive stars, which produce highly relativistic jets (collapsar model). Here we describe gamma- and X-ray observations of the most distant GRB ever observed (GRB 050904): its redshift (z) of 6.29 means that this explosion happened 12.8 billion years ago, corresponding to a time when the Universe was just 890 million years old, close to the reionization era. This means that not only did stars form in this short period of time after the Big Bang, but also that enough time had elapsed for them to evolve and collapse into black holes. 相似文献
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G. Greenspan R. W. A. Rees G. D. Link C. P. Boyd R. C. Jones H. E. Alburn 《Cellular and molecular life sciences : CMLS》1974,30(4):328-329
Zusammenfassung Die mikrobiologische 1-Hydroxylierung vond-Norgestrel und Norethisteron durch den MikroorganismusBotryodiplodia malorum wird beschrieben. Ausserdem wurde 11-Hydroxynorethisteron isoliert und charakterisiert.
Acknowledgement. The authors want to express their appreciation to Dr.H. Smith for advice and encouragement through the course of this work. We wish to thank Dr.T. Chang, Dr.C. Hetzel and Mr.C. Kuhlman for obtaining and interpreting the mass spectra and Mr.B. Hormann for NMR decoupling experiments and analytical services. 相似文献
Acknowledgement. The authors want to express their appreciation to Dr.H. Smith for advice and encouragement through the course of this work. We wish to thank Dr.T. Chang, Dr.C. Hetzel and Mr.C. Kuhlman for obtaining and interpreting the mass spectra and Mr.B. Hormann for NMR decoupling experiments and analytical services. 相似文献
59.
Summary The production of intraglandular colloid, brought about by the cyclic breakdown of intermediate lobe cells, is related to the synthesis of hormones in the hypophysis. By analyzing the shift of the amino acid, cystine, during various phases of the gland's cycle it is apparent that hormones, as well as other protein determinants of immunological importance, are transported by way of the intraglandular cleft to the venous circulation and to the cerebrospinal fluid.This study was supported by a grant from the National Research Council of Canada. 相似文献
60.