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961.
Julia K.J. Ahlskog Christoph E. Dumelin Sabrina Trüssel Jessica Mårlind Dario Neri 《Bioorganic & medicinal chemistry letters》2009,19(16):4851-4856
We describe the synthesis and characterization of two acetazolamide derivatives containing either a charged fluorophore or an albumin-binding moiety, which restrict binding to carbonic anhydrase IX and XII present on tumor cells. In vivo studies showed the preferentially targeting of tumor cells by the fluorescent acetazolamide derivative and the ability of the albumin-binding acetazolamide derivative to cause tumor retardation in a SK-RC-52 xenograft model of cancer. 相似文献
962.
Modern assistive devices are very sophisticated systems with multiple degrees of freedom. However, an effective and user-friendly control of these systems is still an open problem since conventional human-machine interfaces (HMI) cannot easily accommodate the system’s complexity. In HMIs, the user is responsible for generating unique patterns of command signals directly triggering the device functions. This approach can be difficult to implement when there are many functions (necessitating many command patterns) and/or the user has a considerable impairment (limited number of available signal sources). In this study, we propose a novel concept for a general-purpose HMI where the controller and the user communicate bidirectionally to select the desired function. The system first presents possible choices to the user via electro-tactile stimulation; the user then acknowledges the desired choice by generating a single command signal. Therefore, the proposed approach simplifies the user communication interface (one signal to generate), decoding (one signal to recognize), and allows selecting from a number of options. To demonstrate the new concept the method was used in one particular application, namely, to implement the control of all the relevant functions in a state of the art commercial prosthetic hand without using any myoelectric channels. We performed experiments in healthy subjects and with one amputee to test the feasibility of the novel approach. The results showed that the performance of the novel HMI concept was comparable or, for some outcome measures, better than the classic myoelectric interfaces. The presented approach has a general applicability and the obtained results point out that it could be used to operate various assistive systems (e.g., prosthesis vs. wheelchair), or it could be integrated into other control schemes (e.g., myoelectric control, brain-machine interfaces) in order to improve the usability of existing low-bandwidth HMIs. 相似文献
963.
964.
965.
Ala-Eddine Deghmane Carole Veckerlé Dario Giorgini Eva Hong Corinne Ruckly Muhamed-Kheir Taha 《PLoS pathogens》2009,5(5)
Infections by Neisseria meningitidis show duality between frequent asymptomatic carriage and occasional life-threatening disease. Bacterial and host factors involved in this balance are not fully understood. Cytopathic effects and cell damage may prelude to pathogenesis of isolates belonging to hyper-invasive lineages. We aimed to analyze cell–bacteria interactions using both pathogenic and carriage meningococcal isolates. Several pathogenic isolates of the ST-11 clonal complex and carriage isolates were used to infect human epithelial cells. Cytopathic effect was determined and apoptosis was scored using several methods (FITC-Annexin V staining followed by FACS analysis, caspase assays and DNA fragmentation). Only pathogenic isolates were able to induce apoptosis in human epithelial cells, mainly by lipooligosaccharide (endotoxin). Bioactive TNF-α is only detected when cells were infected by pathogenic isolates. At the opposite, carriage isolates seem to provoke shedding of the TNF-α receptor I (TNF-RI) from the surface that protect cells from apoptosis by chelating TNF-α. Ability to induce apoptosis and inflammation may represent major traits in the pathogenesis of N. meningitidis. However, our data strongly suggest that carriage isolates of meningococci reduce inflammatory response and apoptosis induction, resulting in the protection of their ecological niche at the human nasopharynx. 相似文献
966.
Genomic selection in forest tree breeding 总被引:2,自引:0,他引:2
Genomic selection (GS) involves selection decisions based on genomic breeding values estimated as the sum of the effects of
genome-wide markers capturing most quantitative trait loci (QTL) for the target trait(s). GS is revolutionizing breeding practice
in domestic animals. The same approach and concepts can be readily applied to forest tree breeding where long generation times
and late expressing complex traits are also a challenge. GS in forest trees would have additional advantages: large training
populations can be easily assembled and accurately phenotyped for several traits, and the extent of linkage disequilibrium
(LD) can be high in elite populations with small effective population size (N
e) frequently used in advanced forest tree breeding programs. Deterministic equations were used to assess the impact of LD
(modeled by N
e and intermarker distance), the size of the training set, trait heritability, and the number of QTL on the predicted accuracy
of GS. Results indicate that GS has the potential to radically improve the efficiency of tree breeding. The benchmark accuracy
of conventional BLUP selection is reached by GS even at a marker density ~2 markers/cM when N
e ≤ 30, while up to 20 markers/cM are necessary for larger N
e. Shortening the breeding cycle by 50% with GS provides an increase ≥100% in selection efficiency. With the rapid technological
advances and declining costs of genotyping, our cautiously optimistic outlook is that GS has great potential to accelerate
tree breeding. However, further simulation studies and proof-of-concept experiments of GS are needed before recommending it
for operational implementation. 相似文献
967.
Primary structure and antiproteolytic activity of a Kunitz-type inhibitor from bovine spleen 总被引:1,自引:0,他引:1
E Fioretti G Iacopino M Angeletti D Barra F Bossa F Ascoli 《The Journal of biological chemistry》1985,260(21):11451-11455
The amino acid sequence of protease inhibitor II, previously isolated from bovine spleen, has been completely elucidated and reveals a high homology (approximately 90%) with that of bovine pancreatic trypsin inhibitor (BPTI), the well-known Kunitz inhibitor. The secondary and tertiary structure of this new inhibitor appears similar to that of BPTI. Whereas its affinity for bovine trypsin, chymotrypsin, and trypsinogen is almost identical to that of BPTI, the affinity for porcine pancreatic kallikrein is decreased, as expected on the basis of the amino acid substitutions. Analysis of the pH dependence of the affinity constant confirms the previous assignment of the ionizable groups, whose pK values are perturbed on complex formation, to kallikrein and not to the inhibitor molecule. 相似文献
968.
International Journal of Primatology - 相似文献
969.
970.
Angeletti Ruth Hogue; Bergwerk Ari J.; Novikoff Phyllis M.; Wolkoff Allan W. 《American journal of physiology. Cell physiology》1998,275(3):C882
Both adult liver and choroid plexus express the organic aniontransport protein (oatp1) and transport[35S]bromosulfophthalein(BSP). Studies of the developing rat liver reveal that oatp1 mRNA andprotein do not begin to be expressed until 15 days postnatal and are atadult levels by 30 days. Uptake of[35S]BSP follows thesame time course. In contrast, neonatal rat choroid plexus expressesoatp1 mRNA and protein. When quantified on a weight basis, the uptakeof [35S]BSP in choroidplexus is lower in the adult than at earlier stages of development.Although fluorescence confocal microscopy of adult rat choroid plexusshows that oatp is localized to the apical surface, facing thecerebrospinal fluid, this method reveals an intracellular localizationof oatp1 in the neonate. Approximately 12 wk are required for theappearance of the adult pattern of distribution. Changes in thelocalization and activity of oatp1 during development could play animportant role in the pathobiology of maturation of the liver and thecentral nervous system. 相似文献