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排序方式: 共有3698条查询结果,搜索用时 31 毫秒
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Enrique Martínez-Campos Ana Civantos Juan Alfonso Redondo Rodrigo Guzmán Mónica Pérez-Perrino Alberto Gallardo Viviana Ramos Inmaculada Aranaz 《AAPS PharmSciTech》2017,18(4):974-982
Three types of chitosan-based films have been prepared and evaluated: a non-modified chitosan film bearing cationizable aliphatic amines and two films made of N-sulfopropyl chitosan derivatives bearing both aliphatic amines and negative sulfonate groups at different ratios. Cell adhesion and proliferation on chitosan films of C2C12 pre-myoblastic cells and B16 cells as tumoral model have been tested. A differential cell behavior has been observed on chitosan films due to their different surface modification. B16 cells have shown lower vinculin expression when cultured on sulfonated chitosan films. This study shows how the interaction among cells and material surface can be modulated by physicochemical characteristics of the biomaterial surface, altering tumoral cell adhesion and proliferation processes. 相似文献
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Dysregulated molecular pathways in amyotrophic lateral sclerosis–frontotemporal dementia spectrum disorder 下载免费PDF全文
Frontotemporal dementia (FTD), the second most common form of dementia in people under 65 years of age, is characterized by progressive atrophy of the frontal and/or temporal lobes. FTD overlaps extensively with the motor neuron disease amyotrophic lateral sclerosis (ALS), especially at the genetic level. Both FTD and ALS can be caused by many mutations in the same set of genes; the most prevalent of these mutations is a GGGGCC repeat expansion in the first intron of C9ORF72. As shown by recent intensive studies, some key cellular pathways are dysregulated in the ALS‐FTD spectrum disorder, including autophagy, nucleocytoplasmic transport, DNA damage repair, pre‐mRNA splicing, stress granule dynamics, and others. These exciting advances reveal the complexity of the pathogenic mechanisms of FTD and ALS and suggest promising molecular targets for future therapeutic interventions in these devastating disorders. 相似文献
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Marcelo A. Barria Abhisek Mukherjee Dennisse Gonzalez-Romero Rodrigo Morales Claudio Soto 《PLoS pathogens》2009,5(5)
Prions are the proteinaceous infectious agents responsible for Transmissible Spongiform Encephalopathies. Compelling evidence supports the hypothesis that prions are composed exclusively of a misfolded version of the prion protein (PrPSc) that replicates in the body in the absence of nucleic acids by inducing the misfolding of the cellular prion protein (PrPC). The most common form of human prion disease is sporadic, which appears to have its origin in a low frequency event of spontaneous misfolding to generate the first PrPSc particle that then propagates as in the infectious form of the disease. The main goal of this study was to mimic an early event in the etiology of sporadic disease by attempting de novo generation of infectious PrPSc
in vitro. For this purpose we analyzed in detail the possibility of spontaneous generation of PrPSc by the protein misfolding cyclic amplification (PMCA) procedure. Under standard PMCA conditions, and taking precautions to avoid cross-contamination, de novo generation of PrPSc was never observed, supporting the use of the technology for diagnostic applications. However, we report that PMCA can be modified to generate PrPSc in the absence of pre-existing PrPSc in different animal species at a low and variable rate. De novo generated PrPSc was infectious when inoculated into wild type hamsters, producing a new disease phenotype with unique clinical, neuropathological and biochemical features. Our results represent additional evidence in support of the prion hypothesis and provide a simple model to study the mechanism of sporadic prion disease. The findings also suggest that prion diversity is not restricted to those currently known, and that likely new forms of infectious protein foldings may be produced, resulting in novel disease phenotypes. 相似文献
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Timmers LF Ducati RG Sánchez-Quitian ZA Basso LA Santos DS de Azevedo WF 《Journal of molecular modeling》2012,18(2):467-479
Cytidine Deaminase (CD) is an evolutionarily conserved enzyme that participates in the pyrimidine salvage pathway recycling cytidine and deoxycytidine
into uridine and deoxyuridine, respectively. Here, our goal is to apply computational techniques in the pursuit of potential
inhibitors of Mycobacterium tuberculosis CD (MtCDA) enzyme activity. Molecular docking simulation was applied to find the possible hit compounds. Molecular dynamics simulations
were also carried out to investigate the physically relevant motions involved in the protein-ligand recognition process, aiming
at providing estimates for free energy of binding. The proposed approach was capable of identifying a potential inhibitor,
which was experimentally confirmed by IC50 evaluation. Our findings open up the possibility to extend this protocol to different databases in order to find new potential
inhibitors for promising targets based on a rational drug design process. 相似文献
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The intraganglionic laminar endings in the esophagus of the cat and the rhesus monkey show absolute equivalence between the results in both species from the morphological standpoint. The different types of apparatus found are described, with their location in the esophagus and their percentage distribution in relation to the different portions of its wall. The osmium tetroxide-zinc iodide technique gives pictures equivalent to those using silver impregnations, with the added advantage that the former brings out the morphological details more clearly, to the point of showing up the peculiar characteristics of the edges with their thorn-like protrusions. The complete independence of these structures within the ganglion is confirmed, and evidence is provided for rejecting the possibility that they might be dendritic prolongations of the neuronal elements composing the intramural ganglia. A possible afferent function is proposed, which, however, must be considered an open question, pending the results of further experimental investigation. 相似文献
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Paloma Rocha Arakaki Paula Andrea Borges Salgado Joo Diego de Agostini Losano Dbora Rodrigues Gonalves Rodrigo del Rio do Valle Ricardo Jos Garcia Pereira Marcilio Nichi 《American journal of primatology》2019,81(12)
Wild animal genetic resource banking (GRB) represents a valuable tool in conservation breeding programs, particularly in cases involving endangered species such as the golden‐headed lion tamarin (Leontopithecus chrysomelas). Thus, we aimed to assess a sperm freezing protocol for golden‐headed lion tamarins using two different exenders: BotuBOV® (BB) and Test Yolk Buffer® (TYB). Ejaculates were collected by penile vibrostimulation from animals housed at São Paulo Zoological Park Foundation, São Paulo, Brazil, and after immediate analysis, two aliquots were diluted in BB and TYB. Postthawing samples were evaluated for total and progressive motility, plasma membrane and acrosome integrities, mitochondrial activity, susceptibility to oxidative stress, and sperm–egg‐binding. No differences between BB and TYB were found for most seminal parameters, except for acrosome integrity and susceptibility to oxidative stress (in both cases BB showed higher values). However, in spite of these differences and regardless of the extender used, postthaw sperm motility and viability with the described protocol were encouraging (on average >50% and >80%, respectively), indicating that sperm cryopreservation may be a short‐term measure for the conservation of golden‐headed lion tamarins. 相似文献