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排序方式: 共有239条查询结果,搜索用时 31 毫秒
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Akman L Yamashita A Watanabe H Oshima K Shiba T Hattori M Aksoy S 《Nature genetics》2002,32(3):402-407
Many insects that rely on a single food source throughout their developmental cycle harbor beneficial microbes that provide nutrients absent from their restricted diet. Tsetse flies, the vectors of African trypanosomes, feed exclusively on blood and rely on one such intracellular microbe for nutritional provisioning and fecundity. As a result of co-evolution with hosts over millions of years, these mutualists have lost the ability to survive outside the sheltered environment of their host insect cells. We present the complete annotated genome of Wigglesworthia glossinidia brevipalpis, which is composed of one chromosome of 697,724 base pairs (bp) and one small plasmid, called pWig1, of 5,200 bp. Genes involved in the biosynthesis of vitamin metabolites, apparently essential for host nutrition and fecundity, have been retained. Unexpectedly, this obligate's genome bears hallmarks of both parasitic and free-living microbes, and the gene encoding the important regulatory protein DnaA is absent. 相似文献
75.
Early-onset ataxia with ocular motor apraxia and hypoalbuminemia is caused by mutations in a new HIT superfamily gene 总被引:18,自引:0,他引:18
Date H Onodera O Tanaka H Iwabuchi K Uekawa K Igarashi S Koike R Hiroi T Yuasa T Awaya Y Sakai T Takahashi T Nagatomo H Sekijima Y Kawachi I Takiyama Y Nishizawa M Fukuhara N Saito K Sugano S Tsuji S 《Nature genetics》2001,29(2):184-188
Friedreich ataxia (FRDA), the most common autosomal recessive neurodegenerative disease among Europeans and people of European descent, is characterized by an early onset (usually before the age of 25), progressive ataxia, sensory loss, absence of tendon reflexes and pyramidal weakness of the legs. We have recently identified a unique group of patients whose clinical presentations are characterized by autosomal recessive inheritance, early age of onset, FRDA-like clinical presentations and hypoalbuminemia. Linkage to the FRDA locus, however, was excluded. Given the similarities of the clinical presentations to those of the recently described ataxia with oculomotor apraxia (AOA) linked to chromosome 9p13, we confirmed that the disorder of our patients is also linked to the same locus. We narrowed the candidate region and have identified a new gene encoding a member of the histidine triad (HIT) superfamily as the 'causative' gene. We have called its product aprataxin; the gene symbol is APTX. Although many HIT proteins have been identified, aprataxin is the first to be linked to a distinct phenotype. 相似文献
76.
Kou Takahashi Joshua B. Foster Chien-Liang Glenn Lin 《Cellular and molecular life sciences : CMLS》2015,72(18):3489-3506
Glutamate is the predominant excitatory neurotransmitter in the central nervous system. Excitatory amino acid transporter 2 (EAAT2) is primarily responsible for clearance of extracellular glutamate to prevent neuronal excitotoxicity and hyperexcitability. EAAT2 plays a critical role in regulation of synaptic activity and plasticity. In addition, EAAT2 has been implicated in the pathogenesis of many central nervous system disorders. In this review, we summarize current understanding of EAAT2, including structure, pharmacology, physiology, and functions, as well as disease relevancy, such as in stroke, Parkinson’s disease, epilepsy, amyotrophic lateral sclerosis, Alzheimer’s disease, major depressive disorder, and addiction. A large number of studies have demonstrated that up-regulation of EAAT2 protein provides significant beneficial effects in many disease models suggesting EAAT2 activation is a promising therapeutic approach. Several EAAT2 activators have been identified. Further understanding of EAAT2 regulatory mechanisms could improve development of drug-like compounds that spatiotemporally regulate EAAT2. 相似文献
77.
Akihiro TAKEDA Akira MINOWA Takeo OKU Atsushi SUZUKI Kenji KIKUCHI Yasuhiro YAMASAKI 《自然科学进展(英文版)》2011,21(1):27-30
Ni-Cu-Zn ferrite/CaTiO_3 and Ni-Cu-Zn ferrite/BaTiO_3 composites which can be applied in low temperature co-fired ceramic(LTCC) technology were synthesized by conventional solid-state reaction at temperature lower than 950℃.Influence of the microstructures and the gap parameterδ/D on the complex permeability of the above two composites was investigated.The modifiedδ/D values of the above two composites show a good fit to the magnetic circuit model.The dielectric properties of the composites were predicte... 相似文献
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Influence of pulsing electromagnetic field on the frequency of sister-chromatid exchanges in cultured mammalian cells 总被引:1,自引:0,他引:1
K. Takahashi I. Kaneko M. Date E. Fukada 《Cellular and molecular life sciences : CMLS》1987,43(3):331-332
Summary Exposure of Chinese hamster cells to pulsing electromagnetic field (PEMF) with 0.18–2.5 mT did not influence the baseline frequency of sister-chromatid exchanges (SCE). The results suggest that PEMF with the magnetic intensity examined does not interfere with DNA replication nor produce DNA lesions, thereby leading to an increased frequency of SCE. 相似文献
80.
C. Takahashi K. Yoshihira S. Natori M. Umeda K. Ohtsubo M. Saito 《Cellular and molecular life sciences : CMLS》1974,30(5):529-530
Zusammenfassung Zwei neue Toxine wurden aus den Mycelien und dem Zuchtmedium eines Schimmelpilzes,Aspergillus candidus, sowie aus dem experimentell mit demselben Pilz verschimmelten polierten Reis isoliert. Die beiden Substanzen sind sowohl chemisch als auch toxikologisch voneinander völlig verschieden. 相似文献