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81.
Vissers LE van Ravenswaaij CM Admiraal R Hurst JA de Vries BB Janssen IM van der Vliet WA Huys EH de Jong PJ Hamel BC Schoenmakers EF Brunner HG Veltman JA van Kessel AG 《Nature genetics》2004,36(9):955-957
CHARGE syndrome is a common cause of congenital anomalies affecting several tissues in a nonrandom fashion. We report a 2.3-Mb de novo overlapping microdeletion on chromosome 8q12 identified by array comparative genomic hybridization in two individuals with CHARGE syndrome. Sequence analysis of genes located in this region detected mutations in the gene CHD7 in 10 of 17 individuals with CHARGE syndrome without microdeletions, accounting for the disease in most affected individuals. 相似文献
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J. Dogterom Tj. B. van Wimersma Greidanus D. De Wied 《Cellular and molecular life sciences : CMLS》1976,32(5):659-660
Summary Intraperitoneal and intraventricular injection of histamine induces a very fast and high elevation of vasopressin in rat plasma as determined by radioimmunoassay. The effects are dose and time related. The intraventricular injection is more effective with regard to time and dose than the intraperitoneal injection. 相似文献
85.
van den Bergh S 《Nature》1971,231(5297):35-36
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Meijers-Heijboer H van den Ouweland A Klijn J Wasielewski M de Snoo A Oldenburg R Hollestelle A Houben M Crepin E van Veghel-Plandsoen M Elstrodt F van Duijn C Bartels C Meijers C Schutte M McGuffog L Thompson D Easton D Sodha N Seal S Barfoot R Mangion J Chang-Claude J Eccles D Eeles R Evans DG Houlston R Murday V Narod S Peretz T Peto J Phelan C Zhang HX Szabo C Devilee P Goldgar D Futreal PA Nathanson KL Weber B Rahman N Stratton MR;CHEK-Breast Cancer Consortium 《Nature genetics》2002,31(1):55-59
Mutations in BRCA1 and BRCA2 confer a high risk of breast and ovarian cancer, but account for only a small fraction of breast cancer susceptibility. To find additional genes conferring susceptibility to breast cancer, we analyzed CHEK2 (also known as CHK2), which encodes a cell-cycle checkpoint kinase that is implicated in DNA repair processes involving BRCA1 and p53 (refs 3,4,5). We show that CHEK2(*)1100delC, a truncating variant that abrogates the kinase activity, has a frequency of 1.1% in healthy individuals. However, this variant is present in 5.1% of individuals with breast cancer from 718 families that do not carry mutations in BRCA1 or BRCA2 (P = 0.00000003), including 13.5% of individuals from families with male breast cancer (P = 0.00015). We estimate that the CHEK2(*)1100delC variant results in an approximately twofold increase of breast cancer risk in women and a tenfold increase of risk in men. By contrast, the variant confers no increased cancer risk in carriers of BRCA1 or BRCA2 mutations. This suggests that the biological mechanisms underlying the elevated risk of breast cancer in CHEK2 mutation carriers are already subverted in carriers of BRCA1 or BRCA2 mutations, which is consistent with participation of the encoded proteins in the same pathway. 相似文献
89.
Electrical spin injection and accumulation at room temperature in an all-metal mesoscopic spin valve
Finding a means to generate, control and use spin-polarized currents represents an important challenge for spin-based electronics, or 'spintronics'. Spin currents and the associated phenomenon of spin accumulation can be realized by driving a current from a ferromagnetic electrode into a non-magnetic metal or semiconductor. This was first demonstrated over 15 years ago in a spin injection experiment on a single crystal aluminium bar at temperatures below 77 K. Recent experiments have demonstrated successful optical detection of spin injection in semiconductors, using either optical injection by circularly polarized light or electrical injection from a magnetic semiconductor. However, it has not been possible to achieve fully electrical spin injection and detection at room temperature. Here we report room-temperature electrical injection and detection of spin currents and observe spin accumulation in an all-metal lateral mesoscopic spin valve, where ferromagnetic electrodes are used to drive a spin-polarized current into crossed copper strips. We anticipate that larger signals should be obtainable by optimizing the choice of materials and device geometry. 相似文献
90.
'Inverse' melting of a vortex lattice 总被引:1,自引:0,他引:1
Avraham N Khaykovich B Myasoedov Y Rappaport M Shtrikman H Feldman DE Tamegai T Kes PH Li M Konczykowski M van der Beek K Zeldov E 《Nature》2001,411(6836):451-454
Inverse melting is the process in which a crystal reversibly transforms into a liquid or amorphous phase when its temperature is decreased. Such a process is considered to be very rare, and the search for it is often hampered by the formation of non-equilibrium states or intermediate phases. Here we report the discovery of first-order inverse melting of the lattice formed by magnetic flux lines in a high-temperature superconductor. At low temperatures, disorder in the material pins the vortices, preventing the observation of their equilibrium properties and therefore the determination of whether a phase transition occurs. But by using a technique to 'dither' the vortices, we were able to equilibrate the lattice, which enabled us to obtain direct thermodynamic evidence of inverse melting of the ordered lattice into a disordered vortex phase as the temperature is decreased. The ordered lattice has larger entropy than the low-temperature disordered phase. The mechanism of the first-order phase transition changes gradually from thermally induced melting at high temperatures to a disorder-induced transition at low temperatures. 相似文献