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461.
The binding of phosphorylated heavy meromyosin to regulated F-actin in ghost fibers at high Ca2+ concentration increases, and at low Ca2+ concentration decreases, the anisotropy of intrinsic tryptophan fluorescence of F-actin. The effect is opposite to the effect of the binding of dephosphorylated heavy meromyosin. 相似文献
462.
463.
Epstein-Barr virus genome-positive T lymphocytes in a boy with chronic active EBV infection associated with Kawasaki-like disease 总被引:21,自引:0,他引:21
H Kikuta Y Taguchi K Tomizawa K Kojima N Kawamura A Ishizaka Y Sakiyama S Matsumoto S Imai T Kinoshita 《Nature》1988,333(6172):455-457
Epstein-Barr virus (EBV), a ubiquitous human herpesvirus and an aetiological agent of infectious mononucleosis, has a unique tropism for B lymphocytes. Clinical and laboratory features of chronic active EBV infections are chronic or persistent infectious mononucleosis-like symptoms and high antibody titre against early antigens (EA). Kawasaki disease (KD), aetiology unknown, is thought to be self-limited immunologically mediated vasculitis. Clinical features of KD are fever, rash, mucositis, lymphadenopathy and coronary artery damage. We report here a child with chronic active EBV infection accompanied by dilatation of coronary arteries. All the EBV-determined nuclear antigen (EBNA)-positive lymphocytes had exclusively CD4 antigen, as revealed by dual staining immunofluorescence analysis. Southern blot hybridization showed that the purified CD4+ cells harboured EBV genome. 相似文献
464.
Y. Iwanami 《Cellular and molecular life sciences : CMLS》1984,40(6):568-569
Summary Pollen grains ofLilium auratum which had been stored in n-pentanol, n-butanol and n-propanol for 10 years at –10°C germinated, and the generative nucleus in the pollen tube divided into 2 sperm nuclei. The resting eggs ofArtemia salina soaked in these solvents for 10 years hatched at a high rate. 相似文献
465.
Epidermal growth factor stimulated both [3H]thymidine uptake and proliferation of rat AH66 hepatoma cells. However, the increase in cell number was not accompanied by a proportional increase in the levels of alpha-fetoprotein of the culture media. The effects of EGF on the cell proliferation were antagonized by N6,O2'-dibutyryl cAMP. 相似文献
466.
S. Suzuki Y. Endo R. Miura R. Iizuka 《Cellular and molecular life sciences : CMLS》1984,40(11):1214-1217
Summary The effects of the inhibition of steroidogenesis by trilostane on oocyte maturation were examined by studying spontaneous maturation and fertilization in vitro. 10–6 M trilostane had no influence on the meiotic process, whether the oocytes were naked or not. At a concentration of 10–6 M and 10–7 M trilostane, low normal pronuclear formation and high polyspermy were found during in vitro fertilization. However, no retarded male pronuclear development could be detected in the trilostane-treated group. Thus, steroid producing activity within ova is apparently necessary to prevent multiple sperm penetration, but it has no effect on meiosis or the action of the so-called male pronucleus growth factor (MPGF). 相似文献
467.
Alternative splicing of murine T-cell receptor beta-chain transcripts 总被引:12,自引:0,他引:12
468.
杨文泽 《西南师范大学学报(自然科学版)》1988,(4)
本文削弱了《内-外-∑群与极小非∑群》(陈重穆)一文中定理10.10A:条件而得到相同的结果,即定理 设G是有限群,p是|G|的素因子,且对|G|的任一素因子q有p(?)q-1 ),P是G的p-Sylow子群.若对于P的任一非平凡循环子群P,N_G(P)与C_G(P)都有正规p-补,则G为p-幂零群. 相似文献
469.
X-linked nephrogenic diabetes insipidus (NDI) is a rare disorder in which the kidney is insensitive to the antidiuretic hormone, vasopressin. It has been proposed that the kidney-specific V2 vasopressin receptor, a G protein-coupled receptor, is defective in this disorder as both the disease and the receptor map to Xq28. We report six unique mutations in the V2 receptor gene of five unrelated NDI patients, with one patient having two mutations. The most severely affected patient has a nonsense mutation which would terminate the protein in transmembrane domain III. Other mutations include three missense mutations, a frameshift and one small in-frame deletion. These results represent one of the first examples of recessive mutations affecting a G protein-coupled receptor. 相似文献
470.
M. Takahashi S. Saga S. Nagayoshi M. Imai Y. Tsutsui K. Kato M. Hoshino 《Cellular and molecular life sciences : CMLS》1981,37(2):189-190
Summary A highly sensitive sandwich enzyme immunoassay for the mouse mammary tumor virus (MMTV) is described. The assay can detect 3 ng/ml of MMTV. The enzyme used is ß-D-galactosidase fromEscherichia coli and the solid phase used is a piece of silicon rubber. 相似文献