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101.
Orlandi-Pradines E Almeras L Denis de Senneville L Barbe S Remoué F Villard C Cornelie S Penhoat K Pascual A Bourgouin C Fontenille D Bonnet J Corre-Catelin N Reiter P Pagés F Laffite D Boulanger D Simondon F Pradines B Fusaï T Rogier C 《Microbes and infection / Institut Pasteur》2007,9(12-13):1454-1462
Exposure to vectors of infectious diseases has been associated with antibody responses against salivary antigens of arthropods among people living in endemic areas. This immune response has been proposed as a surrogate marker of exposure to vectors appropriate for evaluating the protective efficacy of antivectorial devices. The existence and potential use of such antibody responses in travellers transiently exposed to Plasmodium or arbovirus vectors in tropical areas has never been investigated. The IgM and IgG antibody responses of 88 French soldiers against the saliva of Anopheles gambiae and Aedes aegypti were evaluated before and after a 5-month journey in tropical Africa. Antibody responses against Anopheles and Aedes saliva increased significantly in 41% and 15% of the individuals, respectively, and appeared to be specific to the mosquito genus. A proteomic and immunoproteomic analysis of anopheles and Aedes saliva allowed for the identification of some antigens that were recognized by most of the exposed individuals. These results suggest that antibody responses to the saliva of mosquitoes could be considered as specific surrogate markers of exposure of travellers to mosquito vectors that transmit arthropod borne infections. 相似文献
102.
Lamarche F Mével M Montier T Burel-Deschamps L Giamarchi P Tripier R Delépine P Le Gall T Cartier D Lehn P Jaffrès PA Clément JC 《Bioconjugate chemistry》2007,18(5):1575-1582
The DNA compacting properties of polyamines (especially spermine) are well-known, hence the use of spermine as the cationic part in several synthetic DNA carriers. Here, we describe the synthesis of modified spermines, with a "lipophosphoramidate" as the lipidic part, and their use for efficient in vitro transfection. Physicochemical measurements (particle size, zeta potentials, pKa determination) and gel retardation assays were also performed. Theoretical membrane-disrupting ability was established by FRET. Taken together, our results indicate that lipophosphoramidates constitute an interesting alternative to "classical" lipidic parts of cationic lipids used as DNA carriers. 相似文献
103.
104.
Coulombel L 《Médecine sciences : M/S》2007,23(6-7):667-670
105.
Yann Gibert Eric Samarut Emmanuel Pasco-Viel Laure Bernard Véronique Borday-Birraux Alexa Sadier Catherine Labbé Laurent Viriot Vincent Laudet 《Proceedings. Biological sciences / The Royal Society》2015,282(1802)
Small variations in signalling pathways have been linked to phenotypic diversity and speciation. In vertebrates, teeth represent a reservoir of adaptive morphological structures that are prone to evolutionary change. Cyprinid fish display an impressive diversity in tooth number, but the signals that generate such diversity are unknown. Here, we show that retinoic acid (RA) availability influences tooth number size in Cyprinids. Heterozygous adult zebrafish heterozygous for the cyp26b1 mutant that encodes an enzyme able to degrade RA possess an extra tooth in the ventral row. Expression analysis of pharyngeal mesenchyme markers such as dlx2a and lhx6 shows lateral, anterior and dorsal expansion of these markers in RA-treated embryos, whereas the expression of the dental epithelium markers dlx2b and dlx3b is unchanged. Our analysis suggests that changes in RA signalling play an important role in the diversification of teeth in Cyprinids. Our work illustrates that through subtle changes in the expression of rate-limiting enzymes, the RA pathway is an active player of tooth evolution in fish. 相似文献
106.
Blood and cloacal swab sampling for avian influenza monitoring has no effect on survival rates of free‐ranging ducks 下载免费PDF全文
Matthieu Guillemain Jocelyn Champagnon Marie‐Lucile Gourlay‐Larour Francois Cavallo Anne‐Laure Brochet Jean Hars Gregoire Massez Thierry George Pierre‐Yves Perroi Veronique Jestin Alain Caizergues 《Ibis》2015,157(4):743-753
Concerns about the spread of avian influenza viruses (AIVs) have led to cloacal swab sampling of hundreds of thousands of birds worldwide as part of AIV surveillance schemes, but the effects of cloacal swabbing have not been adequately evaluated. We tested for differences between swabbed, swabbed and bled, and non‐sampled wild ducks in terms of live re‐encounter and dead recoveries for Common Pochard Aythya ferina and Tufted Duck Aythya fuligula, and also determined re‐encounter and recovery rates for Mallard Anas platyrhynchos and Common Teal Anas crecca. No effects of sampling methods were detected, except in Teal. Re‐encounter rates were lower in sampled Teal than in controls, with annual re‐encounter probabilities being 25% and 35% lower in males and females, respectively. Teal possibly left or avoided sampling sites, or sought sites where they were less detectable after sampling. In general, no deleterious effects were found, suggesting that cloacal swabbing and blood sampling are suitable methods for conducting AIV surveillance in ducks. 相似文献
107.
Burchak ON Pihive EL Maigre L Guinchard X Bouhours P Jolivalt C Schneider D Maurin M Giglione C Meinnel T Paris JM Denis JN 《Bioorganic & medicinal chemistry》2011,19(10):3204-3215
A collection of 3-substituted indole derivatives was prepared using nucleophilic addition of indoles to nitrones. The compounds were then tested for their antibacterial activity against almost thirty bacterial strains representative of common human pathogens. Two types of indolic molecules inhibit the growth of Staphylococcus aureus, including MRSA and VISA strains, with MIC values ranging from 8 to 16 mg/L. 相似文献
108.
Gaertner HF Cerini F Kamath A Rochat AF Siegrist CA Menin L Hartley O 《Bioconjugate chemistry》2011,22(6):1103-1114
Nanoparticles carrying biologically active functional sets (e.g., targeting moiety, payload, tracer) have potential use in a wide range of clinical applications. Though complex, such constructions should, as far as possible, have a defined molecular architecture and be monodisperse. However, the existing methods to achieve this goal are unsuitable for the incorporation of peptides and proteins, and those that provide for orthogonal introduction of two different types of functional element are incompatible with the use of commercially available materials. In this study, we have developed approaches for the production of nanoparticles based on commercially available polyamidoamine (PAMAM) dendrimers. First, we identified an optimized oxime conjugation strategy under which complex dendrimers can be fully decorated not only with model peptides, but also with recombinant proteins (insulin was taken as an example). Second, we developed a strategy based on a two-chain covalent heterodendrimer (a "diblock") based on cystamine core PAMAM dendrimers and used it to generate heterodendrimers, into which a peptide array and a mannose array were orthogonally introduced. Finally, by incorporating a functionalized linker into the diblock architecture we were able to site-specifically introduce a third functional element into the nanoparticle. We exemplified this approach using fluorescein, a mannose array, and a peptide array as the three functionalities. We showed that incorporation of a mannose array into a nanoparticle strongly and specifically enhances uptake by sentinel cells of the immune system, an important property for vaccine delivery applications. These PAMAM dendrimer-based approaches represent a robust and versatile platform for the development of bioactive nanoparticles. 相似文献
109.
Twyffels L Massart C Golstein PE Raspe E Van Sande J Dumont JE Beauwens R Kruys V 《Cellular physiology and biochemistry》2011,28(3):491-496
In the thyroid, the transport of iodide from the extracellular space to the follicular lumen requires two steps: the transport in the cell at the basal side and in the lumen at the apical side. The first step is mediated by the Na(+)/I(-) symporter (NIS). In most reviews and textbooks, the second step is presented as mediated by pendrin. In this review, we analyze this assumption. There are several arguments supporting the concept that indeed pendrin plays an important role in thyroid physiology. However, biochemical, clinical and histological data on the thyroid of a patient with Pendred syndrome do not suggest an essential role in iodide transport, which is corroborated by the lack of a thyroid phenotype in pendrin knockout mice. Experiments in vivo and in vitro on polarized and unpolarized cells show that iodide is transported transport of iodide at the apex of the thyroid cell. Moreover, ectopic expression of pendrin in transfected non-thyroid cells is capable of mediating iodide efflux. It is concluded that pendrin may participate in the iodide efflux into thyroid lumen but not as the unique transporter. Moreover, another role of pendrin in mediating Cl(-)/HCO(3)(-) exchange and controlling luminal pH is suggested. 相似文献
110.
N'Diaye A Chen GK Palmer CD Ge B Tayo B Mathias RA Ding J Nalls MA Adeyemo A Adoue V Ambrosone CB Atwood L Bandera EV Becker LC Berndt SI Bernstein L Blot WJ Boerwinkle E Britton A Casey G Chanock SJ Demerath E Deming SL Diver WR Fox C Harris TB Hernandez DG Hu JJ Ingles SA John EM Johnson C Keating B Kittles RA Kolonel LN Kritchevsky SB Le Marchand L Lohman K Liu J Millikan RC Murphy A Musani S Neslund-Dudas C North KE Nyante S Ogunniyi A Ostrander EA Papanicolaou G Patel S Pettaway CA 《PLoS genetics》2011,7(10):e1002298
Adult height is a classic polygenic trait of high heritability (h
2 ∼0.8). More than 180 single nucleotide polymorphisms (SNPs), identified mostly in populations of European descent, are associated with height. These variants convey modest effects and explain ∼10% of the variance in height. Discovery efforts in other populations, while limited, have revealed loci for height not previously implicated in individuals of European ancestry. Here, we performed a meta-analysis of genome-wide association (GWA) results for adult height in 20,427 individuals of African ancestry with replication in up to 16,436 African Americans. We found two novel height loci (Xp22-rs12393627, P = 3.4×10−12 and 2p14-rs4315565, P = 1.2×10−8). As a group, height associations discovered in European-ancestry samples replicate in individuals of African ancestry (P = 1.7×10−4 for overall replication). Fine-mapping of the European height loci in African-ancestry individuals showed an enrichment of SNPs that are associated with expression of nearby genes when compared to the index European height SNPs (P<0.01). Our results highlight the utility of genetic studies in non-European populations to understand the etiology of complex human diseases and traits. 相似文献