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171.
The development of EEG in 8 male rats from 4 to 16 weeks age were studied chronically. Theta band had the highest power at 5--16 weeks. Especially after 11 weeks, theta band presented a significantly higher peak than that of 4-week-old. In contrast to this, delta band, which had the highest power at 4 weeks, was markedly decreased. 相似文献
172.
The skeletal muscle of members of Orthoptera and Diptera receives an innervation which is probably glutaminergic. Recent study of the ventral muscle fibres in the larvae of the beetle, Tenebrio molitor, has revealed that the transmitter action can be mimicked by the iontophoretic application of L-glutamate to the junctional sites at which the extracellular excitatory postsynaptic potentials (e.p.s.ps) could be recorded (D.Y. and H.W., unpublished observation). Contrary to the evidence favouring glutamate as a transmitter of junctional excitation in insects, some investigators have found that curare (+)tubocrarine, TC), a classic acetylcholine (ACh) antagonist, suppresses the neurally evoked muscle potentials in the fly Sacophaga, and Tenebrio. Here, we have analysed the action of curare on the neuromuscular junction of Tenebrio larvae and found that curare blocked the glutaminergic transmission by antagonising the transmitter at the postsynaptic site. 相似文献
173.
174.
S. Harada T. Hisatsugu J. Takata M. Yamamoto 《Cellular and molecular life sciences : CMLS》1982,38(11):1321-1322
Summary Multiple faceted gallstones with an internal fissure have been examined by gas chromatography-mass spectrometry. In vivo. the fissures probably contain only water vapor. The fissure may be produced by dehydration or water trapping during the stone formation process. 相似文献
175.
Unique cell lines harbouring both Epstein-Barr virus and adult T-cell leukaemia virus, established from leukaemia patients 总被引:8,自引:0,他引:8
Members of three distinct classes of animal virus have been associated with naturally occurring neoplasias in man: Epstein--Barr virus (EBV), a DNA virus belonging to herpesvirus group, papillomavirus, and a novel human RNA (retro) virus, human T-cell leukemia virus or adult T-cell leukaemia (ATL) virus. We have established seven continuous cell lines from ATL patients and 0.1-7% of these cells consistently express ATL-specific antigens (ATLA). EBV-associated nuclear antigen (EBNA) is also found in more than 90% of these cells. We have cloned cells from two of these lines and show here that both ATLA and EBNA were present in the same B-cell clone carrying surface immunoglobulin (sIg). 相似文献
176.
Primary LAMP-2 deficiency causes X-linked vacuolar cardiomyopathy and myopathy (Danon disease) 总被引:19,自引:0,他引:19
Nishino I Fu J Tanji K Yamada T Shimojo S Koori T Mora M Riggs JE Oh SJ Koga Y Sue CM Yamamoto A Murakami N Shanske S Byrne E Bonilla E Nonaka I DiMauro S Hirano M 《Nature》2000,406(6798):906-910
"Lysosomal glycogen storage disease with normal acid maltase" which was originally described by Danon et al., is characterized clinically by cardiomyopathy, myopathy and variable mental retardation. The pathological hallmark of the disease is intracytoplasmic vacuoles containing autophagic material and glycogen in skeletal and cardiac muscle cells. Sarcolemmal proteins and basal lamina are associated with the vacuolar membranes. Here we report ten unrelated patients, including one of the patients from the original case report, who have primary deficiencies of LAMP-2, a principal lysosomal membrane protein. From these results and the finding that LAMP-2-deficient mice manifest a similar vacuolar cardioskeletal myopathy, we conclude that primary LAMP-2 deficiency is the cause of Danon disease. To our knowledge this is the first example of human cardiopathy-myopathy that is caused by mutations in a lysosomal structural protein rather than an enzymatic protein. 相似文献
177.
Ota T Suzuki Y Nishikawa T Otsuki T Sugiyama T Irie R Wakamatsu A Hayashi K Sato H Nagai K Kimura K Makita H Sekine M Obayashi M Nishi T Shibahara T Tanaka T Ishii S Yamamoto J Saito K Kawai Y Isono Y Nakamura Y Nagahari K Murakami K Yasuda T Iwayanagi T Wagatsuma M Shiratori A Sudo H Hosoiri T Kaku Y Kodaira H Kondo H Sugawara M Takahashi M Kanda K Yokoi T Furuya T Kikkawa E Omura Y Abe K Kamihara K Katsuta N Sato K Tanikawa M Yamazaki M Ninomiya K Ishibashi T Yamashita H Murakawa K Fujimori K 《Nature genetics》2004,36(1):40-45
178.
Meiosis is initiated from G1 of the cell cycle and is characterized by a pre-meiotic S phase followed by two successive nuclear divisions. The first of these, meiosis I, differs from mitosis in having a reductional pattern of chromosome segregation. Here we show that meiosis can be initiated from G2 in fission yeast cells by ectopically activating the meiosis-inducing network. The subsequent meiosis I occurs without a pre-meiotic S phase and with decreased recombination, and exhibits a mitotic pattern of equational chromosome segregation. The subsequent meiosis II results in random chromosome segregation. This behaviour is similar to that observed in cells lacking the meiotic cohesin Rec8 (refs 3, 4), which becomes associated with chromosomes at G1/S phase, including the inner centromere, a region that is probably critical for sister-centromere orientation. If the expression of Rec8 is delayed to S phase/G2, then the centromeres behave equationally. We propose that the presence of Rec8 in chromatin is required at the pre-meiotic S phase to construct centromeres that behave reductionally and chromosome arms capable of a high level of recombination, and that this explains why meiosis is initiated from G1 of the cell cycle. 相似文献