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91.
Periodic circadian (24-h) cycles play an important role in daily hormonal and behavioural rhythms. Usually our sleep/wake
cycle, temperature and melatonin rhythms are internally synchronized with a stable phase relationship. When there is a desynchrony
between the sleep/wake cycle and circadian rhythm, sleep disorders such as advanced and delayed sleep phase syndrome can arise
as well as transient chronobiologic disturbances, for example from jet lag and shift work. Appropriately timed bright light
is effective in re-timing the circadian rhythm and sleep pattern to a more desired time, ameliorating these disturbances.
Other less potent retiming effects may also be obtained from the judicious use of melatonin and exercise. 相似文献
92.
Dhar-Chowdhury P Malester B Rajacic P Coetzee WA 《Cellular and molecular life sciences : CMLS》2007,64(23):3069-3083
Glycolysis is an evolutionary conserved metabolic pathway that provides small amounts of energy in the form of ATP when compared
to other pathways such as oxidative phosphorylation or fatty acid oxidation. The ATP levels inside metabolically active cells
are not constant and the local ATP level will depend on the site of production as well as the respective rates of ATP production,
diffusion and consumption. Membrane ion transporters (pumps, exchangers and channels) are located at sites distal to the major
sources of ATP formation (the mitochondria). We review evidence that the glycolytic complex is associated with membranes;
both at the plasmalemma and with membranes of the endo/sarcoplasmic reticular network. We examine the evidence for the concept
that many of the ion transporters are regulated preferentially by the glycolytic process. These include the Na+/K+-ATPase, the H+-ATPase, various types of Ca2+-ATPases, the Na+/H+ exchanger, the ATP-sensitive K+ channel, cation channels, Na+ channels, Ca2+ channels and other channels involved in intracellular Ca2+ homeostasis. Regulation of these pumps, exchangers and ion channels by the glycolytic process has important consequences
in a variety of physiological and pathophysiological processes, and a better understanding of this mode of regulation may
have important consequences for developing future strategies in combating disease and developing novel therapeutic approaches.
Received 20 July 2007; received after revision 30 July 2007; accepted 17 August 2007 相似文献
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94.
针对ADO.NET在处理"丢失的修改"问题时,不支持"关键字和已修改字段"的并发控制问题提出了相应的解决办法;同时对ADO.NET架构本身带来的异常更新问题提供了解决思路. 相似文献
95.
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97.
Gout AM;ADPKD Gene Variant Consortium Ravine D Harris PC Rossetti S Peters D Breuning M Henske EP Koizumi A Inoue S Shimizu Y Thongnoppakhun W Yenchitsomanus PT Deltas C Sandford R Torra R Turco AE Jeffery S Fontes M Somlo S Furu LM Smulders YM Mercier B Ferec C Burtey S Pei Y Kalaydjieva L Bogdanova N McCluskey M Geon LJ Wouters CH Reiterova J Stekrová J San Millan JL Aguiari G Del Senno L 《Nature genetics》2007,39(4):427-428
98.
1 Results The photosynthetic bacterial reaction center (RC) is a membrane protein complex.The RC is composed of three protein subunits and redox components such as bacteriochlorophylls, bacteriopheophytins,and quinones.The RC performs the photochemical electron transfer from the bacteriochlorophyll dimer through a series of electron donor and acceptor molecules to a secondary quinone,QB.QB accepts electrons from a primary quinone,QA,in two sequential electron transfer reactions.The second electron trans... 相似文献
99.
Mutations in the gene encoding the basal body protein RPGRIP1L, a nephrocystin-4 interactor, cause Joubert syndrome 总被引:7,自引:0,他引:7
Arts HH Doherty D van Beersum SE Parisi MA Letteboer SJ Gorden NT Peters TA Märker T Voesenek K Kartono A Ozyurek H Farin FM Kroes HY Wolfrum U Brunner HG Cremers FP Glass IA Knoers NV Roepman R 《Nature genetics》2007,39(7):882-888
Protein-protein interaction analyses have uncovered a ciliary and basal body protein network that, when disrupted, can result in nephronophthisis (NPHP), Leber congenital amaurosis, Senior-L?ken syndrome (SLSN) or Joubert syndrome (JBTS). However, details of the molecular mechanisms underlying these disorders remain poorly understood. RPGRIP1-like protein (RPGRIP1L) is a homolog of RPGRIP1 (RPGR-interacting protein 1), a ciliary protein defective in Leber congenital amaurosis. We show that RPGRIP1L interacts with nephrocystin-4 and that mutations in the gene encoding nephrocystin-4 (NPHP4) that are known to cause SLSN disrupt this interaction. RPGRIP1L is ubiquitously expressed, and its protein product localizes to basal bodies. Therefore, we analyzed RPGRIP1L as a candidate gene for JBTS and identified loss-of-function mutations in three families with typical JBTS, including the characteristic mid-hindbrain malformation. This work identifies RPGRIP1L as a gene responsible for JBTS and establishes a central role for cilia and basal bodies in the pathophysiology of this disorder. 相似文献
100.