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991.
Dan Morris Kenneth Salisbury 《Computer methods in biomechanics and biomedical engineering》2013,16(3):263-279
Many simulation environments – particularly those intended for medical simulation – require solid objects to deform at interactive rates, with deformation properties that correspond to real materials. Furthermore, new objects may be created frequently (for example, each time a new patient's data is processed), prohibiting manual intervention in the model preparation process. This paper provides a pipeline for rapid preparation of deformable objects with no manual intervention, specifically focusing on mesh generation (preparing solid meshes from surface models), automated calibration of models to finite element reference analyses (including a novel approach to reducing the complexity of calibrating nonhomogeneous objects), and automated skinning of meshes for interactive simulation. 相似文献
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993.
Based on the natural sequence of Araneus diadematus Fibroin 4 (ADF4), the recombinant spider silk protein eADF4(C16) has been engineered. This highly repetitive protein has a molecular weight of 48kDa and is soluble in different solvents (hexafluoroisopropanol (HFIP), formic acid and aqueous buffers). eADF4(C16) provides a high potential for various technical applications when processed into morphologies such as films, capsules, particles, hydrogels, coatings, fibers and nonwoven meshes. Due to their chemical stability and controlled morphology, the latter can be used to improve filter materials. In this protocol, we present a procedure to enhance the efficiency of different air filter devices, by deposition of nonwoven meshes of electrospun recombinant spider silk proteins. Electrospinning of eADF4(C16) dissolved in HFIP results in smooth fibers. Variation of the protein concentration (5-25% w/v) results in different fiber diameters (80-1,100 nm) and thus pore sizes of the nonwoven mesh.Post-treatment of eADF4(C16) electrospun from HFIP is necessary since the protein displays a predominantly α-helical secondary structure in freshly spun fibers, and therefore the fibers are water soluble. Subsequent treatment with ethanol vapor induces formation of water resistant, stable β-sheet structures, preserving the morphology of the silk fibers and meshes. Secondary structure analysis was performed using Fourier transform infrared spectroscopy (FTIR) and subsequent Fourier self-deconvolution (FSD).The primary goal was to improve the filter efficiency of existing filter substrates by adding silk nonwoven layers on top. To evaluate the influence of electrospinning duration and thus nonwoven layer thickness on the filter efficiency, we performed air permeability tests in combination with particle deposition measurements. The experiments were carried out according to standard protocols. 相似文献
994.
Marcus L. Basiri Stephanie Blachon Yiu-Cheung Frederick Chim Tomer Avidor-Reiss 《Journal of visualized experiments : JoVE》2013,(79)
Centrosomes are conserved microtubule-based organelles whose structure and function change dramatically throughout the cell cycle and cell differentiation. Centrosomes are essential to determine the cell division axis during mitosis and to nucleate cilia during interphase. The identity of the proteins that mediate these dynamic changes remains only partially known, and the function of many of the proteins that have been implicated in these processes is still rudimentary. Recent work has shown that Drosophila spermatogenesis provides a powerful system to identify new proteins critical for centrosome function and formation as well as to gain insight into the particular function of known players in centrosome-related processes. Drosophila is an established genetic model organism where mutants in centrosomal genes can be readily obtained and easily analyzed. Furthermore, recent advances in the sensitivity and resolution of light microscopy and the development of robust genetically tagged centrosomal markers have transformed the ability to use Drosophila testes as a simple and accessible model system to study centrosomes. This paper describes the use of genetically-tagged centrosomal markers to perform genetic screens for new centrosomal mutants and to gain insight into the specific function of newly identified genes. 相似文献
995.
目的:探讨研究型医院创建的方法与实践,同时也提出对创建研究型医院所要面临的几点思考.方法:本文对创建研究型医院进行探索,加强对研究医院的认识,围绕创新医院管理,加速研究型医院建设与发展模式的了解.创建研究型医院要将科研与临床融合,全面发展医疗质量、管理理念、科研能力、教学组织、服务态度等综合建设,培养高水平人才,组织创建研究型人才与研究型科室,形成医院主体架构与中坚力量.结果:在医疗改革及行业竞争的形势下找准医院的定位,及时转换发展的模式,促进医院的健康发展,是创建研究型医院的重点.创建研究型医院是整体医院建设的发展方向、政治方向与服务方向,是在新医疗改革下,促进诊疗水平提高的有效保障.结论:创建研究型医院可以将医院发展空间拓展开,为人们提供更为优质的医疗服务,惠及患者,同时为疾病的诊治提供有效支持. 相似文献
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998.
Zhuan-jian Li Wen-jiao Guo Ya-dong Tian Rui-li Han Yu-jia Sun Jing Xue Xian-yong Lan Hong Chen 《Gene》2014
Adipose differentiation-related protein (ADFP) is important for regulation of lipid metabolism and insulin secretion in beta-cells. In this study, we investigated polymorphisms within the caprine ADFP gene and determined its relationship with production traits. As there was no sequence information available for the caprine ADFP gene, we generated DNA sequence data and examined the genomic organisation. The caprine ADFP gene is organised into 7 exons and 6 introns that span approximately 8.7 kbp and is transcribed into mRNA containing 1353 bp of sequence coding for a protein of 450 amino acids. The protein sequences showed substantial similarity (71–99%) to orthologues from cattle, human and mouse. We identified polymorphisms in the sequences using DNA sequencing, PCR-RFLP and forced PCR-RFLP methods. Seven single nucleotide polymorphisms (SNPs) were identified using samples from 4 different goat populations consisting of 1408 healthy and unrelated individuals. Six haplotypes involving the 7 SNPs from the caprine ADFP gene were identified and their effects on production traits were analysed. Haplotype 6 had the highest haplotype frequency and was highly significantly associated with chest circumference and milk yield in the analysed populations. The results of this study suggest that the ADFP gene is a strong candidate gene affecting production traits and may be used for marker-assisted selection and management in Chinese dairy goat breeding programmes. 相似文献
999.
The cysteine and glycine-rich protein 3 (CSRP3) plays an important role in the myofiber differentiation. Here, we identified five SNVs in all exon and intron regions of the CSRP3 gene using DNA sequencing, PCR-RFLP and forced-PCR-RFLP methods in 554 cattle. Four of the five SNVs were significantly associated with growth performance and carcass traits of the cattle. In addition, we evaluated haplotype frequency and linkage disequilibrium coefficient of five sequence variants. The result of haplotype analysis demonstrated 28 haplotypes present in Qinchuan and two haplotypes in Chinese Holstein. Only haplotypes 1 and 8 were being shared by two populations, haplotype 14 had the highest haplotype frequency in Qinchuan (17.4%) and haplotype 8 had the highest haplotype frequency in Chinese Holstein (94.4%). Statistical analyses of combined genotypes indicated that some combined genotypes were significantly or highly significantly associated with growth and carcass traits in the Qinchuan cattle population. qPCR analyses also showed that bovine CSRP3 gene was exclusively expressed in longissimus dorsi muscle and heart tissues. The data support the high potential of the CSRP3 as a marker gene for the improvement of growth performance and carcass traits in selection programs. 相似文献