全文获取类型
收费全文 | 10943篇 |
免费 | 1007篇 |
国内免费 | 5篇 |
专业分类
11955篇 |
出版年
2023年 | 60篇 |
2022年 | 161篇 |
2021年 | 324篇 |
2020年 | 156篇 |
2019年 | 221篇 |
2018年 | 257篇 |
2017年 | 220篇 |
2016年 | 325篇 |
2015年 | 620篇 |
2014年 | 612篇 |
2013年 | 692篇 |
2012年 | 932篇 |
2011年 | 914篇 |
2010年 | 549篇 |
2009年 | 507篇 |
2008年 | 663篇 |
2007年 | 628篇 |
2006年 | 528篇 |
2005年 | 495篇 |
2004年 | 491篇 |
2003年 | 508篇 |
2002年 | 441篇 |
2001年 | 81篇 |
2000年 | 49篇 |
1999年 | 83篇 |
1998年 | 114篇 |
1997年 | 59篇 |
1996年 | 65篇 |
1995年 | 65篇 |
1994年 | 57篇 |
1993年 | 55篇 |
1992年 | 54篇 |
1991年 | 60篇 |
1990年 | 43篇 |
1989年 | 41篇 |
1988年 | 35篇 |
1987年 | 31篇 |
1986年 | 38篇 |
1985年 | 63篇 |
1984年 | 47篇 |
1983年 | 52篇 |
1982年 | 45篇 |
1981年 | 42篇 |
1980年 | 36篇 |
1979年 | 34篇 |
1978年 | 36篇 |
1977年 | 35篇 |
1975年 | 29篇 |
1974年 | 36篇 |
1973年 | 29篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
11.
Emily Olfson Catherine E. Cottrell Nicholas O. Davidson Christina A. Gurnett Jonathan W. Heusel Nathan O. Stitziel Li-Shiun Chen Sarah Hartz Rakesh Nagarajan Nancy L. Saccone Laura J. Bierut 《PloS one》2015,10(9)
The American College of Medical Genetics and Genomics (ACMG) recommends that clinical sequencing laboratories return secondary findings in 56 genes associated with medically actionable conditions. Our goal was to apply a systematic, stringent approach consistent with clinical standards to estimate the prevalence of pathogenic variants associated with such conditions using a diverse sequencing reference sample. Candidate variants in the 56 ACMG genes were selected from Phase 1 of the 1000 Genomes dataset, which contains sequencing information on 1,092 unrelated individuals from across the world. These variants were filtered using the Human Gene Mutation Database (HGMD) Professional version and defined parameters, appraised through literature review, and examined by a clinical laboratory specialist and expert physician. Over 70,000 genetic variants were extracted from the 56 genes, and filtering identified 237 variants annotated as disease causing by HGMD Professional. Literature review and expert evaluation determined that 7 of these variants were pathogenic or likely pathogenic. Furthermore, 5 additional truncating variants not listed as disease causing in HGMD Professional were identified as likely pathogenic. These 12 secondary findings are associated with diseases that could inform medical follow-up, including cancer predisposition syndromes, cardiac conditions, and familial hypercholesterolemia. The majority of the identified medically actionable findings were in individuals from the European (5/379) and Americas (4/181) ancestry groups, with fewer findings in Asian (2/286) and African (1/246) ancestry groups. Our results suggest that medically relevant secondary findings can be identified in approximately 1% (12/1092) of individuals in a diverse reference sample. As clinical sequencing laboratories continue to implement the ACMG recommendations, our results highlight that at least a small number of potentially important secondary findings can be selected for return. Our results also confirm that understudied populations will not reap proportionate benefits of genomic medicine, highlighting the need for continued research efforts on genetic diseases in these populations. 相似文献
12.
Bacterial oxidation of polythionates: determination of tetrathionate with an ion-selective electrode. 下载免费PDF全文
A commercially available ion-selective electrode for nitrate was used to continuously monitor tetrathionate oxidation by Thiobacillus dentrificans. The electrode was much more sensitive to tetrathionate than to nitrate. The same electrode could also be used for the determination of trithionate. 相似文献
13.
Energy calculations have been carried out on high-symmetry cuboctahedral Ni-Al nanoalloy clusters, of varying composition, with the interatomic interactions modelled by the Gupta many-body potential. Relaxations of cuboctahedral fragments cut from the bulk lattice of Ni3Al, with 13-561 atoms, were undertaken, as were relaxations of high symmetry clusters with 55 and 147 atoms. The lowest energy isomers were found to be dominated by three factors: the tendency toward mixing due to the favourable energy of mixing, ΔmixE; the size difference between nickel and aluminium; and the higher cohesive and surface energy of nickel compared to aluminium. The latter two factors favour Al-segregation to the surface. The most stable Ni:Al composition approaches 3:1 for larger clusters. 相似文献
14.
15.
16.
17.
Nicholas Cianciotto Terry Serwold-Davis Neal Groman Giulio Ratti Rino Rappuoli 《FEMS microbiology letters》1990,66(1-3):299-301
Chromosomal restriction fragments of Corynebacterium ulcerans and C. diphtheriae, containing an integration site for corynephages of the beta family, show homology on Southern blots. Homologous DNA in also found in the soil isolate C. glutamicum, although this strain is not susceptible to beta-corynephages. Three of these DNA fragments, one for each bacterial strain, and a fragment of gamma-corynephage DNA previously shown to contain the phage integration site, were cloned and sequenced. Alignment of the 3 bacterial sequences shows a very high degree of homology in a stretch of ca 120 nucleotides, whereas the rest of the sequences is generally non-homologous. Within this common bacterial portion, a segment of ca. 96 nucleotides (core sequence) is also highly homologous to the phage sequence. The first half (ca. 50 bp) of the core sequence is identical in all aligned sequences whereas the second half, which is largely occupied by a stem-and-loop structure, contains point mutations peculiar to each clone. The described sequences are likely to be involved in phage integration/excision processes. 相似文献
18.
19.
20.
Synthetic peptide SH624 (SHHPARTAHYGSLPQK), residues 59–74 of human myelin basic protein (MBP) was found to be encephalitogenic in the rabbit. Four antisera raised, against the peptide were employed in a liquid-phase equilibrium competitive radioimmunoassay with a series of synthetic peptide analogs of the region to probe the structural requirements of the B-cell determinant subsumed within SH624. The cross-reactivities of the four antisera with intact MBP were also examined. Immunochemical analyses of the four antisera suggested specificities directed against a conformational determinant dependent upon residues from the more phylogenetically conserved carboxyl C-terminal region, residues 65–74 (TAHYGSLPQK) of the synthetic immunogen. Peptide analogs shorter than SH624 from the C-terminal end showed no cross-reactivity with any of the reagent antisera while analogs shorter from the N-terminal end and including the encephalitogenic sequence TTHYGSLPQK, as well as, HYGSLPQK were reactive under equilibrium competitive conditions. SH624-reactive antibodies, cross-reactive with purified heterologous MBPs from 10 different species were also identified in all four reagent antisera. The results of these experiments support previous investigations demonstrating the accessibility of the encephalitogenic 65–74 region in intact MBP. They also underscore the importance of B-cell recognition of organ specific antigenic determinants with respect to MBP immunology and, in particular, the recognition of autoreactive determinants in the neighborhood of encephalitogenic centers. 相似文献