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21.
C Medina-Gomez JP Kemp K Estrada J Eriksson J Liu S Reppe DM Evans DH Heppe L Vandenput L Herrera SM Ring CJ Kruithof NJ Timpson MC Zillikens OK Olstad HF Zheng JB Richards B St Pourcain A Hofman VW Jaddoe GD Smith M Lorentzon KM Gautvik AG Uitterlinden R Brommage C Ohlsson JH Tobias F Rivadeneira 《PLoS genetics》2012,8(7):e1002718
To identify genetic loci influencing bone accrual, we performed a genome-wide association scan for total-body bone mineral density (TB-BMD) variation in 2,660 children of different ethnicities. We discovered variants in 7q31.31 associated with BMD measurements, with the lowest P = 4.1 × 10(-11) observed for rs917727 with minor allele frequency of 0.37. We sought replication for all SNPs located ± 500 kb from rs917727 in 11,052 additional individuals from five independent studies including children and adults, together with de novo genotyping of rs3801387 (in perfect linkage disequilibrium (LD) with rs917727) in 1,014 mothers of children from the discovery cohort. The top signal mapping in the surroundings of WNT16 was replicated across studies with a meta-analysis P = 2.6 × 10(-31) and an effect size explaining between 0.6%-1.8% of TB-BMD variance. Conditional analyses on this signal revealed a secondary signal for total body BMD (P = 1.42 × 10(-10)) for rs4609139 and mapping to C7orf58. We also examined the genomic region for association with skull BMD to test if the associations were independent of skeletal loading. We identified two signals influencing skull BMD variation, including rs917727 (P = 1.9 × 10(-16)) and rs7801723 (P = 8.9 × 10(-28)), also mapping to C7orf58 (r(2) = 0.50 with rs4609139). Wnt16 knockout (KO) mice with reduced total body BMD and gene expression profiles in human bone biopsies support a role of C7orf58 and WNT16 on the BMD phenotypes observed at the human population level. In summary, we detected two independent signals influencing total body and skull BMD variation in children and adults, thus demonstrating the presence of allelic heterogeneity at the WNT16 locus. One of the skull BMD signals mapping to C7orf58 is mostly driven by children, suggesting temporal determination on peak bone mass acquisition. Our life-course approach postulates that these genetic effects influencing peak bone mass accrual may impact the risk of osteoporosis later in life. 相似文献
22.
A novel, non-toxic strategy to combat marine biofouling is presented. The technology is paint with additions of up to 43% of industrial protein. Through microbial degradation of the protein component, an oxygen-depleted layer rapidly forms in a 0.2 mm layer close to the paint surface. With the present paint formulations, a stable, O2-depleted layer can persist for 16 weeks. Barnacle larvae (cyprids) did not settle on panels where oxygen saturation was <20%, and cyprids were killed when exposed to O2-free water for more than 1 h. It is also shown that the O2-depleted layer will rapidly reform (within 15 min) after exposure to turbulent flow. Field exposure of panels for 16 weeks showed that paint with protein reduced fouling by barnacles and bryozoans by 80% and close to 100%, respectively. The results suggest that this novel technology may be developed into a non-toxic alternative to copper-based antifouling paints, especially for pleasure boats in sensitive environments. There is clearly potential for further development of the paint formulation, and a full-scale test on a boat-hull suggested that service-life under realistic operations needs to be improved. 相似文献
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Shari Kiekens Dieter Vandenheuvel Géraldine Broeckx Ingmar Claes Camille Allonsius Ilke De Boeck Sofie Thys Jean-Pierre Timmermans Filip Kiekens Sarah Lebeer 《Microbial biotechnology》2019,12(5):849-855
The preservation of the viability of microorganisms in probiotic formulations is the most important parameter ensuring the adequate concentration of live microorganisms at the time of administration. The formulation and processing techniques used to produce these probiotic formulations can influence the preservation of the microbial viability. However, it is also required that the bacteria maintain their key probiotic capacities during processing, formulation and shelf life. In this study, we investigated the impact of spray-drying on different cell wall properties of the model probiotic strain Lactobacillus rhamnosus GG, including its adherence to intestinal epithelial cells. The dltD gene knock-out mutant, L. rhamnosus GG CMPG5540, displaying modified cell wall lipoteichoic acids, showed significantly increased colony-forming units after spray-drying and subsequent storage under standard conditions compared to wild-type L. rhamnosus GG. In contrast, disruption of the biosynthesis of exopolysaccharides or pili expression did not impact survival. However, spray-drying did significantly affect the adherence capacity of L. rhamnosus GG. Scanning electron microscopy confirmed that the pili, key surface factors for adherence to intestinal cells and mucus, were sheared off during the spray-drying process. These data thus highlight that both the functionality and viability of probiotics should be assessed during the spray-drying process and subsequent storage. 相似文献
26.
Viacheslav Katerov Claes Schalén Artem A. Totolian 《Molecular genetics and genomics : MGG》1994,245(1):78-85
Major virulence determinants of group A streptococci, such as M-protein, immunoglobulin Fc-receptors (FcRA, EmmL) and C5a peptidase, appear to be genetically co-regulated, their genes being located within a vir regulon. We studied the organization of these genes in a group A, type M15 strain of Streptococcus pyogenes, previously defined as OF?, by hybridization analysis of chromosomal DNA and of an S. pyogenes gene library in Escherichia coli, and by gene sequencing. Within the vir regulon, in addition to the virR and scpA genes, three so-called emm-related genes were found: fcrA, emmL and enn. Whereas IgG Fc-binding proteins were encoded by fcrA and emmL, the product of enn was not identified. The presence of three emm-related genes in this region is reminescent of vir regulon organization in OF+ rather than OF? strains as earlier defined by others. Furthermore, analysis of the deduced product of the emmL gene showed deletions and amino acid substitutions within the PGTS-rich domain and membrane anchor, which thus resembles corresponding products of OF+ rather than OF? strains. In view of these findings, the opacity factor (OF) activity of the strain was tested using growth supernatant, with negative outcome. However, a concentrated SDS cell extract revealed definite OF activity. One of two other type M15 reference strains also showed definite OF activity in SDS extracts. We therefore propose that type M15 strains belong to the OF+ category but often show low levels of expression of OF. 相似文献
27.
Glaucoma is a group of ocular disorders leading to reduced visual capabilities and sometimes blindness. The biochemical defect
is unknown but it is shown that reduced drainage of the aqueous humour from the anterior chamber may lead to increased intraocular
pressure and gradual atrophy of the optic neurons. Families with various forms of autosomal dominant (AD) glaucoma have been
linked to 1q21-31, 2cen-q13, 4q25-27, and 13q14 and autosomal recessive congenital glaucoma have been localized to chromosome
1p36 and 2p21. Recently, a locus for AD iridogoniodysgenesis anomaly (IGDA) was mapped to chromosome 6p25. This study refines
the localization of IGDA to an approximately 6–cM interval between D6S1600 and D6S1617/D6S1713 at 6p25-tel, based on recombinations
in affected individuals with AD juvenile-onset glaucoma and concomitant iridogoniodysgenesis.
Received: 5 May 1997 / Accepted: 15 June 1997 相似文献
28.
Sjögren-Larsson syndrome (SLS) is an autosomal recessive disorder characterized by congenital ichthyosis, spastic di- or tetraplegia, and mental retardation. SLS has been reported to occur in many populations but the highest incidence is in the north of Sweden. The gene causing SLS encodes a fatty aldehyde dehydrogenase (FALDH). In the present study, a point mutation in exon 7 of the FALDH gene was found in SLS patients of northern Swedish origin. The mutation consists of a C-to-T exchange at nucleotide position 943 in the cDNA. As a consequence, a highly conserved proline is replaced by a serine. The mutation was found in 49 out of 58 affected chromosomes and could be the most widely spread SLS mutation in the world. 相似文献
29.
P. Claes A. Billiau E. De Clercq J. Desmyter E. Schonne H. Vanderhaeghe P. De Somer 《Journal of virology》1970,5(3):313-320
Chlorite-oxidized oxypolysaccharides are polyacetal carboxylic acids. They inhibited the cytopathic effect of vesicular stomatitis virus in mouse embryo cell cultures challenged at low input multiplicity. After intraperitoneal injection of these compounds in mice, interferon appeared in the circulation. The compounds also protected mice against lethal mengovirus infection and against the development of experimental pox lesions on the tail. Chlorite-oxidized oxyamylose was antiviral only when at least 64% of the glucopyranose units were oxidized, an observation which suggested a correlation between charge density and antiviral effect. The antiviral activity was also influenced by the molecular weight, as demonstrated by the fact that chlorite-oxidized dextrans which had a high intrinsic viscosity were more active than those with low intrinsic viscosity. 相似文献
30.
12alpha-hydroxylation of 7alpha-hydroxy-4-cholesten-3-one by a reconstituted system from rat liver microsomes 总被引:2,自引:0,他引:2
Claes Bernhardsson Ingemar Björkhem Henry Danielsson Kjell Wikvall 《Biochemical and biophysical research communications》1973,54(3):1030-1038
A preparation of partially purified cytochrome P-450 from rat liver microsomes was found to catalyze 12α-hydroxylation of 7α-hydroxy-4-cholesten-3-one in the presence of NADPH and phosphatidyl choline. The reaction was stimulated two- to four-fold by addition of a preparation of cytochrome P-450 reductase. The reaction was inhibited by carbon monoxide to a considerably less extent than other hydroxylations catalyzed by the reconstituted system. In the presence of optimal concentrations of cytochrome P-450 reductase, cytochrome P-450 prepared from livers of starved rats catalyzed the 12α-hydroxylation more efficiently than cytochrome P-450 prepared from livers of normal rats or rats treated with phenobarbital. 相似文献