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21.
Osteoblast progenitor cells (OBPCs) isolated from bone marrow have the ability to differentiate into osteoblasts and thus potential therapeutic use to tissue-engineer bone. In order for OBPCs to be available for clinical use a means of storing viable cells is necessary. The aim of this study was to determine whether a simple method of cryopreservation had an effect on osteogenic differentiation or growth of OBPCs isolated from fresh human bone marrow. Stro-1 was used to identify the isolated OBPCs. The osteoblastic potential of the marrow cells was confirmed as culture with osteogenic supplements (OS) significantly increased osteoblastic protein production (alkaline phosphatase (ALP), osteopontin and osteocalcin) compared with standard conditions (P less than 0.05). Ten further marrow aspirates were harvested; each was halved for either cryopreservation or control culture. Primary cultures from both populations formed colonies with recognised OBPC morphology. OS stimulated both cryopreserved and control populations to produce significantly more osteoblastic proteins (P less than 0.05) and there was no significant difference between the increase in osteogenic proteins when cultured with OS (P great than 0.2). The proliferation rate after 5 days in culture was not significantly affected by cryopreservation (P greater than 0.05). It has been suggested that OBPCs are immuno-privileged; so allogenic cells could be implanted into patients for tissue engineering bone without causing a hypersensitivity reaction. Our study demonstrates a method of storage, which allows OBPCs to be available for use without affecting osteoblastic potential or viability. 相似文献
22.
Abachi S Derrick M Kooijman P Musgrave B Price L Repond J Sugano K Blockus D Brabson BB Brom J Jung C Ogren H Rust DR Snyder A Cork B Akerlof C Chapman J Errede D Ken MT Kesten P Meyer DI Neal H Nitz D Thun R Tschirhart R Baringer P Bylsma BG Debonte R Low EH McIlwain RL Miller DH Ng CR Rangan K Shibata E 《Physical review D: Particles and fields》1990,41(7):2045-2056
23.
Jung C Abachi S Akerlof C Baringer P Beltrami I Blockus D Bonvicini G Brabson B Brom JM Bylsma BG Chapman J Cork B DeBonte R Derrick M Errede D Gan KK Gray SW Guillaud J Harnew N Kesten P Koltick D Kooijman P Loeffler FJ Loos JS Low EH McIlwain RL Meyer DI Miller DH Musgrave B Neal H Ng CR Nitz D Ogren H Price LE Rangan LK Repond J Rust DR Schlereth J Shibata EI Sugano K Thun R Trinko T Valdata-Nappi M Weiss JM Willutzky M Wood DE 《Physical review letters》1986,56(17):1775-1778
24.
Baringer P Abachi S Akerlof C Beltrami I Blockus D Bonvicini G Brabson B Brom JM Bylsma BG Chapman J Cork B DeBonte R Derrick M Daigo M Errede D Gan KK Gray SW Guillaud J Harnew N Jung C Kesten P Koltick D Kooijman P Loeffler FJ Loos JS Low EH McIlwain RL Meyer DI Miller DH Musgrave B Neal H Nitz D Ng CR Ogren H Price LE Rangan LK Rust DR Schlereth J Seidl AA Shibata EI Sugano K Thun R Trinko T Valdata-Nappi M Weiss JM Willutzky M Wood DE 《Physical review letters》1986,56(13):1346-1349
25.
Abachi S Akerlof C Baringer P Beltrami I Blockus D Bonvicini G Brabson B Bylsma BG Chapman J Cork B DeBonte R Derrick M Errede D Gan KK Gray SW Harnew N Jung C Kesten P Koltick D Kooijman P Loeffler FJ Loos JS Low EH McIlwain RL Meyer DI Miller DH Musgrave B Neal H Nitz D Ng CR Ogren H Price LE Rangan LK Rust DR Schlereth J Seidl AA Shibata EI Sugano K Thun R Trinko T Valdata-Nappi M Weiss JM Willutzky M Wood DE 《Physical review letters》1986,56(10):1039-1042
26.
Derrick M Fernandez E Fries R Hyman L Kooijman P Loos JS Musgrave B Price LE Schlereth J Sugano K Weiss JM Wood DE Baranko G Baringer P Blockus D Brabson B Forden GE Gray SW Jung C Neal H Ogren H Rust DR Valdata-Nappi M Akerlof C Bonvicini G Chapman J Errede D Harnew N Kesten P Kooijman S Meyer DI Nitz D Rubin D Seidl AA Thun R Trinko T Willutzky M Beltrami I Bylsma BG DeBonte R Koltick D Gan KK Loeffler FJ Low EH Mallik U McIlwain RL Miller DH Ng CR Ong PP Rangan LK Shibata EI Wilson aR Cork B 《Physical review letters》1985,54(24):2568-2571
27.
28.
Sem Raj Tamang Andreas J. Achazi Haley S. Rust Pramod Dhungana Pere Miró James D. Hoefelmeyer 《Tetrahedron》2019,75(16):2365-2370
The title compound was evaluated as catalyst for Suzuki coupling of aryl halides (X?=?I, Br) with phenylboronic acid at room temperature. The rates of the reactions increase with increasing Hammet sigma constant of m-substituents on the arylhalide. The presence of ortho groups on the arylhalides had the effect of lowering the reaction rates. Density functional theory study of the mechanism for the formation of a Pd(0) complex from the title molecule was performed. Reductive elimination of chloride and the η4-BCCC moiety was endergonic and ruled out as a likely pathway. Instead, conversion of the title molecule to phenyl({2-[mesityl(quinolin-8-yl-κN)boryl]-3,5-dimethylphenyl}methyl-κC)palladium(II) complex is thermodynamically favored and predicted to further react with the solvent and the Suzuki coupling reagents to undergo reductive elimination of diphenyl to form a reactive Pd(0) complex. 相似文献
29.
We demonstrate that bulk band structure can have a strong influence in scanning tunneling microscopy measurements by resolving electronic interference patterns associated with scattering phenomena of bulk states at a metal surface and reconstructing the bulk band topology. Our data reveal that bulk information can be detected because states at the edge of the surface-projected bulk band have a predominant role on the scattering patterns. With the aid of density functional calculations, we associate this effect with an intrinsic increase in the projected density of states of edge states. This enhancement is characteristic of the three-dimensional bulk band curvature, a phenomenon analog to a van Hove singularity. 相似文献
30.
The fluorine substituted thiourea 2,6-F2C6H3C(O)NHC(S)NEt2 was prepared in good yield from the reaction of 2,6-F2C6H3C(O)Cl with KSCN and Et2NH in acetone. Using this compound several heteroleptic, monocationic Pd(II), Pt(II) and Ru(II) complexes of the type cis-[M{κ2S,O-2,6-F2C6H3C(O)NC(S)NEt2}(L)]PF6 [M = Pt, Pd; L = (Ph3P)2, tBu2bipy, 1,10-phen] as well as [Ru(η6-p-cym){κ2S,O-2,6-F2C6H3C(O)NC(S)NEt2}(PPh3)]PF6 were prepared in high yields. The compounds were characterised by spectroscopic methods and, in one case, by single crystal X-ray diffraction. 相似文献