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991.
Roxo-Rosa M da Costa G Luider TM Scholte BJ Coelho AV Amaral MD Penque D 《Proteomics》2006,6(7):2314-2325
Potential biological markers for cystic fibrosis (CF) lung disease were identified by comparative proteomics profiling of nasal cells from deletion of phenylalanine residue 508 (F508del)-homozygous CF patients and non-CF controls. From the non-CF 2-DE gels, 65 spots were identified by MS, and a reference 2-DE map was thus established. The majority of those correspond to ubiquitously expressed proteins. Consistent with the epithelial origin of this tissue, some of the identified proteins are epithelial markers (e.g. cytokeratins, palate lung and nasal epithelium clone protein (PLUNC), and squamous cell carcinoma antigen 1). Comparison of this protein profile with the one similarly obtained for CF nasal cells revealed a set of differentially expressed proteins. These included proteins related to chronic inflammation and some others involved in oxidative stress injury. Alterations were also observed in the levels of cytoskeleton proteins, being probably implicated with cytoskeleton organization changes described to occur in CF-airways. Lower levels were found for some mitochondrial proteins suggesting an altered mitochondrial metabolism in CF. Differential expression was also found for two more enzymes that have not been previously associated to CF. Further studies will clarify the involvement of such proteins in CF pathophysiology and whether they are targets for CF therapy. 相似文献
992.
993.
In spite of their tiny dimensions (3×5 mm2), the strongly honey-scented flowers of Guazuma ulmifolia (Malvaceae–Byttnerioideae) provide six sexual chambers. A central female unit is surrounded by five interconnected male compartments. At the onset of anthesis the strap-shaped odoriferous petal appendages form an open star with the female chamber in the centre. Hereafter, they wilt, intermingle and finally lock access to the stigma. Meanwhile, wilting sepals liberate new entrances from the back between the petal claws. They give way to nectar-offering male chambers. In each of them a well-lit (but closed) window lures the visitor into a standard position for passive pollen uptake. Finally, the insects have to back out of one of the rear entrances. It remains unknown how the minute visitors (maximum height ca. 0.5 mm) – if ever – overcome the distance to another Guazuma tree. 相似文献
994.
Giacomelli C Le Men L Borsali R Lai-Kee-Him J Brisson A Armes SP Lewis AL 《Biomacromolecules》2006,7(3):817-828
The micellization behavior of a diblock copolymer comprising a highly hydrophilic and biocompatible poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) corona-forming block and a pH-sensitive poly(2-(diisopropylamino)ethyl methacrylate) (PDPA) core-forming block (PMPC-b-PDPA) has been studied by static and dynamic light scattering (SDLS), transmission electron microscopy (TEM), and potentiometry. Self-assembly of PMPC-b-PDPA copolymers with two different DPA volume fractions (phi(DPA)) leads to narrowly distributed and structurally distinct spherical micelles, as evidenced by their molecular weight (M(w,mic)), aggregation number (N(agg)), hydrodynamic radius (R(H)), corona width (W), and core radius (R(c)). The excellent potential of these pH-responsive micelles as nanosized drug delivery vehicles was illustrated by the encapsulation of dipyridamole (DIP), a model hydrophobic drug that dissolves in acid solutions and becomes insoluble above pH 5.8, which is comparable to the pK(a) of the PDPA block. The influence of micelle structure (namely M(w,mic), N(agg), R(H), W, and R(c)) on drug loading content, drug loading efficiency, partition coefficient, and release kinetics was investigated and confirmed by fluorescence spectroscopy studies. The maximum dipyridamole loadings within PMPC(30)-b-PDPA(30) (R(H) = 14.0 nm; W = 4.8 nm; R(c) = 9.2 nm) and PMPC(30)-b-PDPA(60) (R(H) = 27.1 nm; W = 11.0 nm; R(c) = 16.1 nm) micelles were 7 and 12% w/w(p), respectively. This preferential solubilization of DIP into micelles formed by copolymer chains having longer core-forming blocks (i.e., possessing larger core volumes) reflects the larger partition coefficient (K(V)) of DIP between the aqueous phase and PMPC(30)-b-PDPA(60) micelles (K(V) = 5.7 x 10(4)) compared to PMPC(30)-b-PDPA(30) micelles (K(V) = 1.1 x 10(4)). This enhanced ability of PMPC(30)-b-PDPA(60) aggregates to entrap/stabilize small hydrophobic molecules also produces slower release kinetics. Rapid release can be triggered by lowering the pH to induce micellar dissociation. 相似文献
995.
Aguilar-Mahecha A Hassan S Ferrario C Basik M 《Omics : a journal of integrative biology》2006,10(3):311-326
The widespread use of DNA microarrays has led to the discovery of many genes whose expression profile may have significant clinical relevance. The translation of this data to the bedside requires that gene expression be validated as protein expression, and that annotated clinical samples be available for correlative and quantitative studies to assess clinical context and usefulness of putative biomarkers. We review two microarray platforms developed to facilitate the clinical validation of candidate biomarkers: tissue microarrays and reverse-phase protein microarrays. Tissue microarrays are arrays of core biopsies obtained from paraffin-embedded tissues, which can be assayed for histologically-specific protein expression by immunohistochemistry. Reverse-phase protein microarrays consist of arrays of cell lysates or, more recently, plasma or serum samples, which can be assayed for protein quantity and for the presence of post-translational modifications such as phosphorylation. Although these platforms are limited by the availability of validated antibodies, both enable the preservation of precious clinical samples as well as experimental standardization in a high-throughput manner proper to microarray technologies. While tissue microarrays are rapidly becoming a mainstay of translational research, reverse-phase protein microarrays require further technical refinements and validation prior to their widespread adoption by research laboratories. 相似文献
996.
997.
Cláudio M. R. Melo Francisco C. Silva Carlos Henrique A. M. Gomes Antonio M. Solé-Cava Cristiano Lazoski 《Biological invasions》2010,12(3):441-449
We report on the invasion of Brazil by the Pacific oyster Crassostrea gigas, and discuss the likely routes of invasion. Because this phenotypically diverse oyster sometimes resembles the native species
C. brasiliana and C. rhizophorae, its invasion went unnoticed until it was detected through the analysis of DNA sequences for ribosomal 16S and the ribosomal
second internal transcribed spacer. C. gigas was found amongst the native species in oyster banks up to 100 km south of oyster farms in South Brazil. Under most circumstances,
water temperatures in the coastal southerly Brazil current would be too high to allow for the establishment of stable populations
of C. gigas, but the production of spat in oyster farm laboratories has probably selected for resistance to warmer temperatures, which
would promote invasion by C. gigas. 相似文献
998.
999.
Padmanabhan S Melander O Johnson T Di Blasio AM Lee WK Gentilini D Hastie CE Menni C Monti MC Delles C Laing S Corso B Navis G Kwakernaak AJ van der Harst P Bochud M Maillard M Burnier M Hedner T Kjeldsen S Wahlstrand B Sjögren M Fava C Montagnana M Danese E Torffvit O Hedblad B Snieder H Connell JM Brown M Samani NJ Farrall M Cesana G Mancia G Signorini S Grassi G Eyheramendy S Wichmann HE Laan M Strachan DP Sever P Shields DC Stanton A Vollenweider P Teumer A Völzke H Rettig R Newton-Cheh C 《PLoS genetics》2010,6(10):e1001177
Hypertension is a heritable and major contributor to the global burden of disease. The sum of rare and common genetic variants robustly identified so far explain only 1%–2% of the population variation in BP and hypertension. This suggests the existence of more undiscovered common variants. We conducted a genome-wide association study in 1,621 hypertensive cases and 1,699 controls and follow-up validation analyses in 19,845 cases and 16,541 controls using an extreme case-control design. We identified a locus on chromosome 16 in the 5′ region of Uromodulin (UMOD; rs13333226, combined P value of 3.6×10−11). The minor G allele is associated with a lower risk of hypertension (OR [95%CI]: 0.87 [0.84–0.91]), reduced urinary uromodulin excretion, better renal function; and each copy of the G allele is associated with a 7.7% reduction in risk of CVD events after adjusting for age, sex, BMI, and smoking status (H.R. = 0.923, 95% CI 0.860–0.991; p = 0.027). In a subset of 13,446 individuals with estimated glomerular filtration rate (eGFR) measurements, we show that rs13333226 is independently associated with hypertension (unadjusted for eGFR: 0.89 [0.83–0.96], p = 0.004; after eGFR adjustment: 0.89 [0.83–0.96], p = 0.003). In clinical functional studies, we also consistently show the minor G allele is associated with lower urinary uromodulin excretion. The exclusive expression of uromodulin in the thick portion of the ascending limb of Henle suggests a putative role of this variant in hypertension through an effect on sodium homeostasis. The newly discovered UMOD locus for hypertension has the potential to give new insights into the role of uromodulin in BP regulation and to identify novel drugable targets for reducing cardiovascular risk. 相似文献
1000.
A. R. Amaral M. C. Silva L. M. Möller L. B. Beheregaray M. M. Coelho 《Conservation Genetics》2010,11(3):1143-1146
Here we report the development and characterization of 17 anonymous nuclear markers for cetacean species. These markers were
isolated from a genomic library built from a common dolphin (genus Delphinus), and tested across several families within Cetacea. An average of 1 SNP per 272 bp was found in 10 anonymous markers screened
for polymorphism within the genus Delphinus (total of 6,537 bp sequenced). These markers represent a significant addition to the set of tools used in genetic studies
of cetaceans where population and species boundaries have to be inferred in order to implement proper conservation strategies. 相似文献