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排序方式: 共有114条查询结果,搜索用时 15 毫秒
111.
Mutations in ENPP1 are associated with 'idiopathic' infantile arterial calcification 总被引:8,自引:0,他引:8
Rutsch F Ruf N Vaingankar S Toliat MR Suk A Höhne W Schauer G Lehmann M Roscioli T Schnabel D Epplen JT Knisely A Superti-Furga A McGill J Filippone M Sinaiko AR Vallance H Hinrichs B Smith W Ferre M Terkeltaub R Nürnberg P 《Nature genetics》2003,34(4):379-381
Idiopathic infantile arterial calcification (IIAC; OMIM 208000) is characterized by calcification of the internal elastic lamina of muscular arteries and stenosis due to myointimal proliferation. We analyzed affected individuals from 11 unrelated kindreds and found that IIAC was associated with mutations that inactivated ecto-nucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1). This cell surface enzyme generates inorganic pyrophosphate (PP(i)), a solute that regulates cell differentiation and serves as an essential physiologic inhibitor of calcification. 相似文献
112.
Marjan Radi Behnam Dezfouli Kamalrulnizam Abu Bakar Shukor Abd Razak Mohammad Ali Nematbakhsh 《清华大学学报》2011,16(5):475-490
The existing multipath routing protocols for wireless sensor networks demonstrate the efficacy of traffic distribution over multiple paths to fulfill the Quality of Service (QoS) requirements of different applications.However,the performance of these protocols is highly affected by the characteristics of the wireless channel and may be even inferior to the performance of single-path approaches.Specifically,when multiple adjacent paths are being used concurrently,the broadcast nature of wireless channels res... 相似文献
113.
Understanding the energetics of molecular interactions is fundamental to all of the central quests of structural biology including structure prediction and design, mapping evolutionary pathways, learning how mutations cause disease, drug design, and relating structure to function. Hydrogen-bonding is widely regarded as an important force in a membrane environment because of the low dielectric constant of membranes and a lack of competition from water. Indeed, polar residue substitutions are the most common disease-causing mutations in membrane proteins. Because of limited structural information and technical challenges, however, there have been few quantitative tests of hydrogen-bond strength in the context of large membrane proteins. Here we show, by using a double-mutant cycle analysis, that the average contribution of eight interhelical side-chain hydrogen-bonding interactions throughout bacteriorhodopsin is only 0.6 kcal mol(-1). In agreement with these experiments, we find that 4% of polar atoms in the non-polar core regions of membrane proteins have no hydrogen-bond partner and the lengths of buried hydrogen bonds in soluble proteins and membrane protein transmembrane regions are statistically identical. Our results indicate that most hydrogen-bond interactions in membrane proteins are only modestly stabilizing. Weak hydrogen-bonding should be reflected in considerations of membrane protein folding, dynamics, design, evolution and function. 相似文献
114.
High frequency of BRAF mutations in nevi 总被引:23,自引:0,他引:23
Pollock PM Harper UL Hansen KS Yudt LM Stark M Robbins CM Moses TY Hostetter G Wagner U Kakareka J Salem G Pohida T Heenan P Duray P Kallioniemi O Hayward NK Trent JM Meltzer PS 《Nature genetics》2003,33(1):19-20
To evaluate the timing of mutations in BRAF (v-raf murine sarcoma viral oncogene homolog B1) during melanocytic neoplasia, we carried out mutation analysis on microdissected melanoma and nevi samples. We observed mutations resulting in the V599E amino-acid substitution in 41 of 60 (68%) melanoma metastases, 4 of 5 (80%) primary melanomas and, unexpectedly, in 63 of 77 (82%) nevi. These data suggest that mutational activation of the RAS/RAF/MAPK pathway in nevi is a critical step in the initiation of melanocytic neoplasia but alone is insufficient for melanoma tumorigenesis. 相似文献