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91.
ApreliminarystudyonS.asotuslinnaeusandS.soldatovimeridionalisChenbyDNAfingerPrinting¥LiuYong;HongXijun(DepartmentofLifeScienc... 相似文献
92.
Nitric oxide (NO) is an important biological messenger in the regulation of tissue homeostasis. It exhibits a wide range of effects during physiological and pathophysiological processes. Typical beneficial properties of NO include the regulation of vascular tone,the protection of cells against apoptosis, the modulation of immune responses, and the killing of microbial pathogens. On the other hand,NO may cause severe vasodilation and myocardial depression during bacterial sepsis or act as a cytotoxic and tissue-damaging molecule in autoimmune diseases. Mitogen-activated protein kinase (MAPK) is a family of serine/threonine protein kinases that are widely distributed in mammalian cells. MAPK cascade plays pivotal roles in gene expression, cell proliferation, differentiation, neuronal survival and programmed cell death under a variety of experimental conditions. MAPKs transduce the signal for the cellular response to extracellular stresses or stimuli. The relation between them, however, has never been reviewed. Based on our researches and other reports in the field, we review their reciprocal regulatory functions. 相似文献
93.
Varon R Gooding R Steglich C Marns L Tang H Angelicheva D Yong KK Ambrugger P Reinhold A Morar B Baas F Kwa M Tournev I Guerguelcheva V Kremensky I Lochmüller H Müllner-Eidenböck A Merlini L Neumann L Bürger J Walter M Swoboda K Thomas PK von Moers A Risch N Kalaydjieva L 《Nature genetics》2003,35(2):185-189
94.
KONG Dongdong WANG Dong HU Yong JU Chuanli WANG Yingdian HE Yikun & SUN Jingsan . Key Laboratory of Photosynthesis Environmental MolecularPhysiology Institute of Botany Chinese Academy of Sciences Bei-jing China . College of Life Sciences Beijing Normal University Beijing China . Department of Biology Capital Normal University Beijing China Correspondence should be addressed to Sun Jingsan 《科学通报(英文版)》2003,48(12):1188-1192
As the important cellular organelles in plants, plas-tids comprise one of the primary features that distinguish plant cells from those of other eukaryotes. Seen from the origin, plastids derive from endosymbiotic photosynthetic bacteria. Subsequently, plastids have evolved to become essential components for plant cell function. Besides the important role of chloroplasts in photosynthesis, some water-soluble proteins that involved in biosynthesis of starch, fatty acids, amino acids, nucleic aci… 相似文献
95.
LEE Hyun jin SIM Tai jung JANG Yong ll PARK Soon young BAE Hae young 《重庆邮电学院学报(自然科学版)》2004,16(5):50-57
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location, because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function. 相似文献
96.
Wang Shao-wei Zhu Qiu-ping Yang Yong School of Electronic Information Wuhan University Wuhan Hubei China 《武汉大学学报:自然科学英文版》2004,9(1)
0 IntroductionInmultimediacommunicationsystems,thecomplexcouplingbetweenaloudspeakerandamicrophonecanproduceechowhichwillseriouslycutdownthecommunicationquality .Soitiscrucialtocanceltheechowithsomeeffectivemethods.Acousticechocancellers(AEC)areusuallyusedtoeliminatelongdelayechointerferences.Typicalapplicationsareinlongdistancetelephonecircuitsorinterminalswherelongprocessingdelayexists.Fig .1showsthebasicstructureofanadaptivevoiceechocanceller.Fig .1 Thebasicstructureofanadaptivevoiceec… 相似文献
97.
XU XiaoPing YAO YingMing ZHANG Yong SHEN Qi 《科学通报(英文版)》2007,52(12):1623-1628
Lanthanide methoxides supported by carbon-bridged bis(phenolate) ligands 2,2′-methylene-bis(6-tert- butyl-4-methylphenoxo) (MBMP2-) [(MBMP)Ln( μ-OMe)(THF)2]2 (Ln = Nd (1), Yb (2)) were synthesized in high yields by the protolysis reaction using (C5H5)3Ln(THF) as starting materials, and complex 1 was structurally characterized. The coordination geometry around the center metal can be best described as a distorted octahedron. Complexes 1 and 2 were shown to be efficient initiators for the ring-opening polymerization of 2,2-dimethyltrimethylene carbonate (DTC) and L-lactide. The mechanism of DTC polymerization was explored by the end group analysis of the oligomer. 相似文献
98.
To investigate the phylogenetic relationship and biogeography of bacterioplankton in polar oceans, four Psychrobacter strains, BSw10170, BSw20352, BSw20370, and BSw20461, isolated from seawater of the Bering Sea, the Chukchi Sea, and the Prydz Bay, were characterized by 16S rDNA sequencing and physiological and biochemical testing. Results demonstrated that close relationships existed between the Arctic and Antarctic strains with sequence similarities higher than 97%. These four Psychrobacter strains not only showed almost identical phenotypic characteristics among them, but also shared a lot of similarities with those related Psychrobacter species, indicating that psychrotolerance and halotolerance of Psychrobacter strains may be among the reasons for their bipolar, even global distribution in marine environments at the genus level. 相似文献
99.
WANG ShaoWu WEN XinYu LUO Yong DONG WenJie ZHAO ZongCi YANG Bao 《科学通报(英文版)》2007,52(23):3272-3280
This paper reports a study on reconstructing temperature series for ten regions of China over the last 1000 years with a time resolution of 10 a. The regions concerned are: Northeast, North, East, South China, Taiwan, Central, Southwest, Northwest China, Xinjiang and Qinghai-Tibet Plateau. A variety of proxy data, such as ice core, tree-rings, stalagmites, peat, lake sediments, pollen and historical records, were validated with instrumental observations made in the last 120 years, and applied in the recon- struction of the temperature series. A temperature series for whole China is then established by aver- aging the ten regional series with a weighting proportional to the area of each region. Finally, tem- perature variations for the last 1000 years are examined, with special focus placed on the characteris- tics of the Medieval Warm Period (MWP), the Little Ice Age (LIA), and Modern Warming (MW). 相似文献
100.
Seven terraces along the Weihe River in Longxi basin have been investigated. These terraces all consist of archetypal duality in structure, namely the floodplain deposits and the layer of gravels overlaid by varying thickness of the loess. By resorting to various dating approaches such as palaeomagnetic, optically stimulated luminescenece (OSL), 14C and loess-paleosol sequence, we provide preliminary timing of these seven terraces along upper Weihe River. Analysis on sedimentation characteristics and dating of these terraces showed that seven terraces may be jointly generated by tectonic uplifts and climatic changes. Tectonic uplifts may accommodate initial river incision, and climatic change may be responsible for processes of subsequent channel widening and aggradation. Aggradation normally occurs during glacial periods, in contrast to down-cuttings during transitions from glacial to interglacial period. Moreover, on the basis of the timings and heights of these terraces, we infer that the long-term rate of river incision was determined to be 0.2 m/kyr during the last 870 kyr, which differs from other river incision rates. This discrepancy may reflect spatio-temporal differentiation of tectonic activities in the Qinling orogenic belt during the Pleistocene. 相似文献