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991.
Jian Chen Haiyang Xia Fujun Dang Qingyu Xu Wenjun Li Zhongjun Qin 《Applied microbiology and biotechnology》2015,99(23):10141-10149
992.
Catherine J Libby Sajina Gc Gloria A. Benavides Jennifer L. Fisher Sarah E. Williford Sixue Zhang Anh Nhat Tran Emily R. Gordon Amber B. Jones Kaysaw Tuy William Flavahan Juan Gordillo Ashlee Long Sara J. Cooper Brittany N. Lasseigne Corinne E. Augelli-Szafran Victor Darley-Usmar Anita B. Hjelmeland 《Cell Adhesion & Migration》2021,15(1):101
993.
994.
Unperturbed chain conformations are evaluated assuming separable chain configuration energies. Spatial chain propagations are constructed assuming an equiprobable occurrence of conformational states within topographically selected portions of the allowed energy space. Random coil dimensions, along with spatial representations of some single chains of α-linked glucans, such as amylose, pseudo-nigerose, nigeran and linear dextran are reported. Significant architectural differences are observed for these different α-linked glucan chains, since disordered random-coil as well as persistent pseudo-helical character, either cyclic or linear, are found, depending on the type of glycosidic linkage. 相似文献
995.
Karen Müller Smith Maria Elisabetta Maragnoli Pooja M. Phull Kathy May Tran Lisha Choubey Flora M. Vaccarino 《PloS one》2014,9(8)
Fibroblast growth factors (Fgfs) and their receptors (Fgfr) are expressed in the developing and adult CNS. Previous studies demonstrated a decrease in cortical interneurons and locomotor hyperactivity in mice with a conditional Fgfr1 deletion generated in radial glial cells during midneurogenesis (Fgfr1f/f;hGfapCre+). Here, we report earlier and more extensive inactivation of Fgfr1 in neuroepithelial cells of the CNS (Fgfr1f/f;NesCre+). Similar to findings in Fgfr1f/f;hGfapCre+ mice, parvalbumin positive (PV+) cortical interneurons are also decreased in the neocortex of Fgfr1f/f;NesCre+ mice when compared to control littermates (Fgfr1f/f). Fgfr1f/f;NesCre+ embryos do not differ from controls in the initial specification of GABAergic cells in the ganglionic eminence (GE) as assessed by in situ hybridization for Dlx2, Mash1 and Nkx2. Equal numbers of GABAergic neuron precursors genetically labeled with green fluorescent protein (GFP) were observed at P0 in Fgfr1f/f;hGfapCre+;Gad1-GFP mutant mice. However, fewer GFP+ and GFP+/PV+ interneurons were observed in these mutants at adulthood, indicating that a decrease in cortical interneuron markers is occurring postnatally. Fgfr1 is expressed in cortical astrocytes in the postnatal brain. To test whether the astrocytes of mice lacking Fgfr1 are less capable of supporting interneurons, we co-cultured wild type Gad1-GFP+ interneuron precursors isolated from the medial GE (MGE) with astrocytes from Fgfr1f/f control or Fgfr1f/f;hGfapCre+ mice. Interneurons grown on Fgfr1 deficient astrocytes had small soma size and fewer neurites per cell, but no differences in cell survival. Decreased soma size of Gad67 immunopositive interneurons was also observed in the cortex of adult Fgfr1f/f;NesCre+ mice. Our data indicate that astrocytes from Fgfr1 mutants are impaired in supporting the maturation of cortical GABAergic neurons in the postnatal period. This model may elucidate potential mechanisms of impaired PV interneuron maturation relevant to neuropsychiatric disorders that develop in childhood and adolescence. 相似文献
996.
997.
Khoa D. Tran Danielle P. Vieira Marco A. Sanchez Jessica Valli Eva Gluenz Scott M. Landfear 《PloS one》2015,10(8)
In a variety of eukaryotes, flagella play important roles both in motility and as sensory organelles that monitor the extracellular environment. In the parasitic protozoan Leishmania mexicana, one glucose transporter isoform, LmxGT1, is targeted selectively to the flagellar membrane where it appears to play a role in glucose sensing. Trafficking of LmxGT1 to the flagellar membrane is dependent upon interaction with the KHARON1 protein that is located at the base of the flagellar axoneme. Remarkably, while Δ
kharon1 null mutants are viable as insect stage promastigotes, they are unable to survive as amastigotes inside host macrophages. Although Δ
kharon1 promastigotes enter macrophages and transform into amastigotes, these intracellular parasites are unable to execute cytokinesis and form multinucleate cells before dying. Notably, extracellular axenic amastigotes of Δ
kharon1 mutants replicate and divide normally, indicating a defect in the mutants that is only exhibited in the intra-macrophage environment. Although the flagella of Δ
kharon1 amastigotes adhere to the phagolysomal membrane of host macrophages, the morphology of the mutant flagella is often distorted. Additionally, these null mutants are completely avirulent following injection into BALB/c mice, underscoring the critical role of the KHARON1 protein for viability of intracellular amastigotes and disease in the animal model of leishmaniasis. 相似文献
998.
Different types of morphogenesis in thin cell layers of Nicotiana tabacum cv. Samsun were studied in relation to changes in the external H+ concentration during cluture. Different initial pHs of the medium, ranging from 3.83 to 6.35, were tested under unbuffered and MES-buffered conditions, in combination with various amounts of indolyl-3-butyric acid and kinetin. The explants were sequentially transferred from MES-free media to MES-supplemented media, as well as reciprocally, to determine possible periods during the morphogenic process that showed a particular sensitivity to the external pH. Starting from pH 3.83, 36 m M MES induced the formation of limited callus and of vegetative and floral shoots as flowers in the control. MES at 50 m M inhibited rhizogenesis and either prevented morphogenesis or induced vegetative buds or flowers, depending on the initial pH. The 4th day of culture was a determining period in the induction of roots and flowers. Rhizogenesis, but not floral or vegetative organogenesis, was related to the theoretical intracellular concentration of indolyl-3-butyric acid. H+ transport might be involved in the regulation of morphogenesis. 相似文献
999.
Vector construction with restriction enzymes (REs) typically involves the ligation of a digested donor fragment (insert) to a reciprocally digested recipient fragment (vector backbone). Creating a suitable cloning plan becomes increasingly difficult for complex strategies requiring repeated insertions such as constructing multiple short hairpin RNA (shRNA) expression vectors for RNA interference (RNAi) studies. The problem lies in the reduced availability of suitable RE recognition sites with an increasing number of cloning events and or vector size. This report details a technically simple, directional cloning solution using REs with compatible cohesive ends that are repeatedly destroyed and simultaneously re-introduced with each round of cloning. Donor fragments can be made by PCR or sub-cloned from pre-existing vectors and inserted ad infinitum in any combination. The design incorporates several cloning cores in order to be compatible with as many donor sequences as possible. We show that joining sub-combinations made in parallel is more time-efficient than sequential construction (of one cassette at a time) for any combination of 4 or more insertions. Screening for the successful construction of combinations using Taq polymerase based PCR became increasingly difficult with increasing number of repeated sequence elements. A Pfu polymerase based PCR was developed and successfully used to amplify combinations of up to eleven consecutive hairpin expression cassettes. The identified PCR conditions can be beneficial to others working with multiple shRNA or other repeated sequences, and the infinitely expandable cloning strategy serves as a general solution applicable to many cloning scenarios. 相似文献
1000.
Tae Sik Hwang Byung Kwan Na Hung Thuan Tran Dae Hee Ahn Doo Hyun Park 《Biotechnology and Bioprocess Engineering》2008,13(6):677-682
In this study, a novel three-compartmented electrochemical bioreactor (3-CEB) was designed in an effort to overcome the disadvantages
of the two-compartmented electrochemical bioreactor (2-CEB) separated with a cation-selective membrane for enrichment of strict
anaerobes. The 3-CEB was comprised of an anode, outlet, and a cathode compartment. The outlet compartment was positioned between
the anode and cathode compartment, and it was separated with the anode side by a rubber plate and with the cathode side by
a porous glass membrane. A platinum wire bridging the anode and outlet compartment operated as a redox passage, however, through
which no material could permeate. Butyrate fermentation bacteria were enriched on the basis of the metabolite production.
Butyrate generated by strict anaerobes was significantly more abundant in the 3-CEB than in the 2-CEB. Acetic acid and lactic
acid generated by facultative anaerobes was relatively higher in the 2-CEB than in the 3-CEB. Meanwhile, butyrate was not
generated in the bioreactor utilized for the control test, to which the electrochemical potential was not charged. In a continuous
culture using the 3-CEB, the majority of the glucose was fermented to butyrate, and the acetate additionally supplied to the
bacterial culture was metabolically reduced to butyrate. More lactate than butyrate was generated from glucose in the 2-CEB. 相似文献