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391.
The structure and nucleotide sequence of the murine lactotransferrin-encoding gene (LTF) deduced partly by direct sequencing of genomic clones in the λ phage vector and partly by enzymatic amplification of genomic DNA segments primed with the oligodeoxyribonucleic primers homologous to the cDNA sequence. The λ phage clones contained the 5′ half of the gene corresponding to the first eight exons and an incomplete ninth exon interrupted by eight introns. Genomic clones corresponding to the 3′ half of the LTF gene could not be obtained on repeated attempts from two different mouse genomic libraries, suggesting the possible presence of unclonable sequences in this part of the gene. Hence, PCR was used to clone the rest of the gene. Four out of the presumed eight remaining introns were cloned along with the flanking exons using PCR. Comparison of the structure of the LTF gene with those of the two other known transferrin-encoding genes, human serum transferrin-encoding gene and chicken ovotransferrin-encoding gene reveals that all three genes have a very similar intron-exon distribution pattern. The hypothesis that the present-day transferrin-encoding genes have originated from duplication of a common ancestral gene is confirmed here at the gene level. An interesting finding is the identification of a region of shared nucleotides between the 5′ flanking regions of the murine LTF and myeloperoxidase-encoding genes, the two genes expressed specifically in neutrophilic granulocytes. 相似文献
392.
Mixtalol (a mixture of long chain aliphatic alcohols varying in chain length from C24 to C32) applied to Brassica juncea plants as foliar spray caused an increase in secondary and tertiary branching with consequent enhancement in seed yield through increased number of inflorescences and siliquae per plant. The percentage of immature siliquae and shattering of siliquae decreased with this treatment. Mixtalol increased total dry matter of plants, partitioning coefficient and harvest index. The contents of starch, protein and oil were also higher in seeds from Mixtalol treated plants. 相似文献
393.
Molecular Biology Reports - Genus Ocimum is known to have species possessing important therapeutic essential oil. The major phytoconstituents of essential oil in Ocimum species are... 相似文献
394.
Yuan Li David Lovett Qiao Zhang Srujana Neelam Ram?Anirudh Kuchibhotla Ruijun Zhu Gregg?G. Gundersen Tanmay?P. Lele Richard?B. Dickinson 《Biophysical journal》2015,109(4):670-686
The nucleus has a smooth, regular appearance in normal cells, and its shape is greatly altered in human pathologies. Yet, how the cell establishes nuclear shape is not well understood. We imaged the dynamics of nuclear shaping in NIH3T3 fibroblasts. Nuclei translated toward the substratum and began flattening during the early stages of cell spreading. Initially, nuclear height and width correlated with the degree of cell spreading, but over time, reached steady-state values even as the cell continued to spread. Actomyosin activity, actomyosin bundles, microtubules, and intermediate filaments, as well as the LINC complex, were all dispensable for nuclear flattening as long as the cell could spread. Inhibition of actin polymerization as well as myosin light chain kinase with the drug ML7 limited both the initial spreading of cells and flattening of nuclei, and for well-spread cells, inhibition of myosin-II ATPase with the drug blebbistatin decreased cell spreading with associated nuclear rounding. Together, these results show that cell spreading is necessary and sufficient to drive nuclear flattening under a wide range of conditions, including in the presence or absence of myosin activity. To explain this observation, we propose a computational model for nuclear and cell mechanics that shows how frictional transmission of stress from the moving cell boundaries to the nuclear surface shapes the nucleus during early cell spreading. Our results point to a surprisingly simple mechanical system in cells for establishing nuclear shapes. 相似文献
395.
396.
Faria Fatima Neelam Pathak Deepti Srivastava Smita Rastogi Verma 《Geomicrobiology journal》2021,38(1):29-35
Abstract Phosphorous (P) that upholds life become unattainable as most of them become unavailable due to the formation of insoluble complexes with cations such as Ca2+, Al3+ and Fe3+ forming a complex calcium phosphate (Ca3(PO4)2), aluminum phosphate (AlPO) and ferrous phosphate (FePO) that results in the decrease of soluble P to a greater extent. There are several reports stating that several rhizospheric fungal species play an important role in solubilizing these insoluble phosphates into a soluble form by the excretion of enzymes like phosphatase, phytase enzymes, and organic acids. In view of this, so we have collected twenty fungal isolates having probable phosphate solubilizing efficiency from different regions of Lucknow, India. Their morphological and biochemical characteristics were tested. Among all, six efficient fungal isolates were further checked at molecular level by using 18S rRNA universal primers and by RAPD means. A dendrogram indicated 40-90% homology i.e., highest similarity was found in between species of Aspergillus flavus and A. biplanus with 33.8% similarity while minimum similarity was observed among A. flavus and Fusarium oxysporum. These findings suggest RAPD proves as, a reliable molecular tool that helps in strain specific discrimination. 相似文献
397.
Richard G A Feachem Neelam K Sekhri Karen L White 《BMJ (Clinical research ed.)》2002,324(7330):135-143
ObjectiveTo compare the costs and performance of the NHS with those of an integrated system for financing and delivery health services (Kaiser Permanente) in California.MethodsThe adjusted costs of the two systems and their performance were compared with respect to inputs, use, access to services, responsiveness, and limited quality indicators.ResultsThe per capita costs of the two systems, adjusted for differences in benefits, special activities, population characteristics, and the cost environment, were similar to within 10%. Some aspects of performance differed. In particular, Kaiser members experience more comprehensive and convenient primary care services and much more rapid access to specialist services and hospital admissions. Age adjusted rates of use of acute hospital services in Kaiser were one third of those in the NHS.ConclusionsThe widely held beliefs that the NHS is efficient and that poor performance in certain areas is largely explained by underinvestment are not supported by this analysis. Kaiser achieved better performance at roughly the same cost as the NHS because of integration throughout the system, efficient management of hospital use, the benefits of competition, and greater investment in information technology.