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51.
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Recurrent de novo point mutations in lamin A cause Hutchinson-Gilford progeria syndrome 总被引:36,自引:0,他引:36
Eriksson M Brown WT Gordon LB Glynn MW Singer J Scott L Erdos MR Robbins CM Moses TY Berglund P Dutra A Pak E Durkin S Csoka AB Boehnke M Glover TW Collins FS 《Nature》2003,423(6937):293-298
Hutchinson-Gilford progeria syndrome (HGPS) is a rare genetic disorder characterized by features reminiscent of marked premature ageing. Here, we present evidence of mutations in lamin A (LMNA) as the cause of this disorder. The HGPS gene was initially localized to chromosome 1q by observing two cases of uniparental isodisomy of 1q-the inheritance of both copies of this material from one parent-and one case with a 6-megabase paternal interstitial deletion. Sequencing of LMNA, located in this interval and previously implicated in several other heritable disorders, revealed that 18 out of 20 classical cases of HGPS harboured an identical de novo (that is, newly arisen and not inherited) single-base substitution, G608G(GGC > GGT), within exon 11. One additional case was identified with a different substitution within the same codon. Both of these mutations result in activation of a cryptic splice site within exon 11, resulting in production of a protein product that deletes 50 amino acids near the carboxy terminus. Immunofluorescence of HGPS fibroblasts with antibodies directed against lamin A revealed that many cells show visible abnormalities of the nuclear membrane. The discovery of the molecular basis of this disease may shed light on the general phenomenon of human ageing. 相似文献
53.
Carpten JD Robbins CM Villablanca A Forsberg L Presciuttini S Bailey-Wilson J Simonds WF Gillanders EM Kennedy AM Chen JD Agarwal SK Sood R Jones MP Moses TY Haven C Petillo D Leotlela PD Harding B Cameron D Pannett AA Höög A Heath H James-Newton LA Robinson B Zarbo RJ Cavaco BM Wassif W Perrier ND Rosen IB Kristoffersson U Turnpenny PD Farnebo LO Besser GM Jackson CE Morreau H Trent JM Thakker RV Marx SJ Teh BT Larsson C Hobbs MR 《Nature genetics》2002,32(4):676-680
We report here the identification of a gene associated with the hyperparathyroidism-jaw tumor (HPT-JT) syndrome. A single locus associated with HPT-JT (HRPT2) was previously mapped to chromosomal region 1q25-q32. We refined this region to a critical interval of 12 cM by genotyping in 26 affected kindreds. Using a positional candidate approach, we identified thirteen different heterozygous, germline, inactivating mutations in a single gene in fourteen families with HPT-JT. The proposed role of HRPT2 as a tumor suppressor was supported by mutation screening in 48 parathyroid adenomas with cystic features, which identified three somatic inactivating mutations, all located in exon 1. None of these mutations were detected in normal controls, and all were predicted to cause deficient or impaired protein function. HRPT2 is a ubiquitously expressed, evolutionarily conserved gene encoding a predicted protein of 531 amino acids, for which we propose the name parafibromin. Our findings suggest that HRPT2 is a tumor-suppressor gene, the inactivation of which is directly involved in predisposition to HPT-JT and in development of some sporadic parathyroid tumors. 相似文献
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J. A. Svoboda A. M. G. Nair Nita Agarwal H. C. Agarwal W. E. Robbins 《Cellular and molecular life sciences : CMLS》1979,35(11):1454-1455
Summary The khapra beetle,Trogoderma granarium Everts, does not dealkylate and convert dietary C28- or C29-phytostorols to C
2T
sterols such as cholesterol. There is, however, an increase in the concentration of cholesterol and campesterol in its tissues relative to the dietary concentrations of these sterols, presumably as a result of selective uptake.We thank Dr S. R. Dutky of the Insect Physiology Laboratory, Agricultural Research, SEA, USDA, Beltsville, Maryland for providing GC-MS analyses. 相似文献
56.
Structural and immunological similarities between simian sarcoma virus gene product(s) and human platelet-derived growth factor 总被引:1,自引:0,他引:1
The predicted amino acid sequence of the simian sarcoma virus (SSV) transforming gene product, p28sis, closely corresponds to that of human platelet-derived growth factor (PDGF). We demonstrate that p28sis rapidly undergoes a series of discrete processing steps including dimer formation and proteolytic digestion to yield molecules structurally and immunologically resembling biologically active PDGF. 相似文献
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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
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Résumé
Manduca sexta (Johannson) est capable de transformer 7 phytostérols en cholestérol. Ainsi, cet insecte peut déalcoyler le - et le-méthyl de même que les groupes méthylène et éthylidènes du carbone 24 et peut hydrogéner la double liaison 22, 23. Quand ces stérols sont combinés au 20, 25-diazacholestérol, on a constaté dans tous les cas que la transformation en cholestérol s'effectue par l'intermédiaire commun, le desmostérol. 相似文献