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21.
URH49 is a mammalian protein that is 90% identical to the DExH/D box protein UAP56, an RNA helicase that is important for splicing and nuclear export of mRNA. Although Saccharomyces cerevisiae and Drosophila express only a single protein corresponding to UAP56, mRNAs encoding URH49 and UAP56 are both expressed in human and mouse cells. Both proteins interact with the mRNA export factor Aly and both are able to rescue the loss of Sub2p (the yeast homolog of UAP56), indicating that both proteins have similar functions. UAP56 mRNA is more abundant than URH49 mRNA in many tissues, although in testes URH49 mRNA is much more abundant. UAP56 and URH49 mRNAs are present at similar levels in proliferating cultured cells. However, when the cells enter quiescence, the URH49 mRNA level decreases 3–6-fold while the UAP56 mRNA level remains relatively constant. The amount of URH49 mRNA increases to the level found in proliferating cells within 5 h when quiescent cells are growth-stimulated or when protein synthesis is inhibited. URH49 mRNA is relatively unstable (T½ = 4 h) in quiescent cells, but is stabilized immediately following growth stimulation or inhibition of protein synthesis. In contrast, there is much less change in the content or stability of UAP56 mRNA following growth stimulation. Our observations suggest that in mammalian cells, two UAP56-like RNA helicases are involved in splicing and nuclear export of mRNA. Differential expression of these helicases may lead to quantitative or qualitative changes in mRNA expression.  相似文献   
22.
This paper focuses on traditional healers (balian)in Bali, Indonesia, to raise new argumentsconcerning the nature of the initiatory sufferingsreportedly experienced by shamans in many cultures.Our evidence suggests that a) contrary to ourexpectations, an initiatory madness or illness isexperienced by a minority rather than the majority ofbalian, and b) whether or not a balian undergoesinitiatory sufferings seems to be linked to gender andto the methods of healing employed – thus womenhealers who employ trance possession are those mostlikely to report an initiatory madness or illness.This leads to the central argument of the paper: c)the nature of the initiatory sufferings, where they dooccur, can be clearly distinguished on several groundsfrom the onset of mental illness among Balinese, bothemically in terms of cultural understandings, andetically in terms of objective criteria. Finally wediscuss the concept of ``autonomous imagination,'suggesting that the key to becoming a balian is notovercoming an initiatory madness but gaining controlover this special mode of imagery thought. We furthersuggest that Western ideas concerning the self andself healing, the superficial resemblance of theinitiatory sufferings to schizophrenia, and thedramatic nature of the initiatory sufferings when theyoccur, have combined to give a misleading prominenceto the role of an initiatory madness in shamanism.  相似文献   
23.
24.
The isolation of an H5N1 influenza A virus from a tree sparrow (Passer montanus) captured in East Java, Indonesia in 2010 is reported here. Its hemagglutinin and neuraminidase were genetically similar to those of human isolates from 2006-2007 in Indonesia. The finding of a tree sparrow H5N1 virus that possesses genetically similar surface molecules to those of human viruses highlights the importance of monitoring resident wild birds, as well as migratory birds, for pandemic preparedness.  相似文献   
25.
TAp63α, a homolog of the p53 tumor suppressor, is a quality control factor in the female germline. Remarkably, already undamaged oocytes express high levels of the protein, suggesting that TAp63α's activity is under tight control of an inhibitory mechanism. Biochemical studies have proposed that inhibition requires the C-terminal transactivation inhibitory domain. However, the structural mechanism of TAp63α inhibition remains unknown. Here, we show that TAp63α is kept in an inactive dimeric state. We reveal that relief of inhibition leads to tetramer formation with ~20-fold higher DNA affinity. In vivo, phosphorylation-triggered tetramerization of TAp63α is not reversible by dephosphorylation. Furthermore, we show that a helix in the oligomerization domain of p63 is crucial for tetramer stabilization and competes with the transactivation domain for the same binding site. Our results demonstrate how TAp63α is inhibited by complex domain-domain interactions that provide the basis for regulating quality control in oocytes.  相似文献   
26.
Twenty-four hydrophobic dicarboxylic acids are described which were evaluated as inhibitors of 14 kDa human platelet phospholipase A2 (HP-PLA2). In general, biarylacetic acid derivatives were found to be more active than biaryl acids or biarylpropanoic acids. More potent inhibitors were obtained when hydrophobic groups were attached to the biaryl acid nucleus using an olefin linkage as compared to an ether linkage. Compounds with larger hydrophobic groups were usually more potent inhibitors of HP-PLA2. Five of the compounds disclosed in this report (2, 4, 28, 36b and 36i) were found to possess significant anti-inflammatory activity in a phorbol ester induced mouse ear edema model of chronic inflammation.  相似文献   
27.
陆宝麟 《昆虫学报》1985,(2):224-224
蚋类是重要吸血双翅昆虫之一。过去对于古北界,尤其是苏联的种类所知较多,但东洋各地区的种类尚缺乏系统的调查。本书可谓这方面的重要专著,是研究东洋界蚋类的必要参考。 在本书编写中,作者除从各大博物馆检视了已有记载种类的模式或副模标本外,还从该群岛的72处进行了采集调查,因而本书对菲律宾的区系具有一定的代表性。  相似文献   
28.
Harman and norharman, known as comutagens of many chemicals, were tested for their effect on the binding to DNA of 3-amino-1-methyl-5H-pyrido(4,3-b)indole, (Trp-P-2), a potent mutagen found with harman and norharman in the pyrolysate of tryptophan (1). We demonstrated that the alteration of the DNA helix by intercalation of these comutagens to DNA does not affect the affinity of this potent mutagen for DNA. Covalent binding, however, was inhibited by the comutagens.  相似文献   
29.
潜叶虫是最小的食叶昆虫,多数只需要一片叶的很小部份,就足够完成它们幼期的发育。它们生活在叶的表皮间,蛀食叶肉。绿色体素被食去後,叶上留着浅或白色的隧道。这种隧道统称潜痕,有各种不同的形状,常可用来辨别虫的种类。  相似文献   
30.
Pongamia (Millettia pinnata) has been widely studied as a potential feedstock for biodiesel fuel, though little is known about its feasibility at a commercial level. Capital budgeting and cash flow analysis was conducted for a potential Pongamia plantation and crushing plant in Queensland, Australia. For annual seed yields ranging from 20 to 80 kg (in shell) per tree, the delivered cost of Pongamia oil was estimated to be between AUD $2.22 and AUD $0.64 per litre. The seed yield range of 20 to 80 kg per tree is roughly equivalent to between 7 and 29 t per hectare at a planting density of 357 trees per hectare. Major components of the delivered cost of (Pongamia) oil are the capital expenses of land acquisition, plantation establishment and the crushing plant construction. The major operational costs include mechanical harvesting; fertiliser; control of weed, pests and diseases; seed crushing; and freight of oil to a refinery. The cost items with the greatest volume sensitivity are the capital expenses, overheads (consisting mostly of salaries and wages of employees) and the expenses associated with harvesting and crushing operations. These costs could be significantly reduced if the seed yield could be increased. Several scenarios were tested to demonstrate the effect of seed yield and oil price on the profitability and cash flow of the Pongamia enterprise. At most plausible oil prices and seed yields, Pongamia oil is not expected to be economically viable.  相似文献   
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