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91.
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93.
Punitha Vasanthan Vijayendran Govindasamy Nareshwaran Gnanasegaran Wijenthiran Kunasekaran Sabri Musa Noor Hayaty Abu Kasim 《Journal of cellular and molecular medicine》2015,19(3):566-580
MicroRNAs (miRNAs) are small non‐coding RNAs that regulate translation of mRNA into protein and play a crucial role for almost all biological activities. However, the identification of miRNAs from mesenchymal stem cells (MSCs), especially from dental pulp, is poorly understood. In this study, dental pulp stem cells (DPSCs) were characterized in terms of their proliferation and differentiation capacity. Furthermore, 104 known mature miRNAs were profiled by using real‐time PCR. Notably, we observed 19 up‐regulated miRNAs and 29 significantly down‐regulated miRNAs in DPSCs in comparison with bone marrow MSCs (BM‐MSCs). The 19 up‐regulated miRNAs were subjected to ingenuity analysis, which were composed into 25 functional networks. We have chosen top 2 functional networks, which comprised 10 miRNA (hsa‐miR‐516a‐3p, hsa‐miR‐125b‐1‐3p, hsa‐miR‐221‐5p, hsa‐miR‐7, hsa‐miR‐584‐5p, hsa‐miR‐190a, hsa‐miR‐106a‐5p, hsa‐mir‐376a‐5p, hsa‐mir‐377‐5p and hsa‐let‐7f‐2‐3p). Prediction of target mRNAs and associated biological pathways regulated by each of this miRNA was carried out. We paid special attention to hsa‐miR‐516a‐3p and hsa‐miR‐7‐5p as these miRNAs were highly expressed upon validation with qRT‐PCR analysis. We further proceeded with loss‐of‐function analysis with these miRNAs and we observed that hsa‐miR‐516a‐3p knockdown induced a significant increase in the expression of WNT5A. Likewise, the knockdown of hsa‐miR‐7‐5p increased the expression of EGFR. Nevertheless, further validation revealed the role of WNT5A as an indirect target of hsa‐miR‐516a‐3p. These results provide new insights into the dynamic role of miRNA expression in DPSCs. In conclusion, using miRNA signatures in human as a prediction tool will enable us to elucidate the biological processes occurring in DPSCs. 相似文献
94.
Zhang Y Lai C Duan J Guan N Ullah K Deng Y 《Applied microbiology and biotechnology》2012,94(3):809-816
Simulated microgravity has been reported to affect the gene, protein expression, and its function in the cells. Semicarbazide-sensitive
amine oxidase (SSAO; E.C.1.4.3.6.) is widely distributed in vascular cells, smooth muscle cells, and adipocytes. It is noteworthy
whether the expression of SSAO is affected under simulated microgravity or not. In this study, an SSAO-transformed Escherichia coli BL21 was constructed firstly. Then, a sensitive, selective, and accurate method based on high-performance liquid chromatography
electrospray ionization triple quadrupole (HPLC-ESI-QQQ) was developed to determine the amount of SSAO in the E. coli BL21. The limit of detection and limit of quantification were 5.0 and 10 fmol, respectively. Finally, SSAO expression in
the recombinant E. coli BL21 was evaluated with various gravity and temperature conditions by HPLC-ESI-QQQ analysis. It is interesting that the tendency
in the alteration of SSAO under simulated microgravity showed temperature difference. At 18 °C, the amount of SSAO in the
inclusion bodies and soluble fractions under the simulated microgravity increased by 83% and 116%, respectively, compared
with normal gravity. However, the decrease by 38% and 49% in the inclusion bodies and soluble fractions under the simulated
microgravity was observed at 37 °C. Results obtained here indicate that the SSAO expression under simulated microgravity is
dramatically sensitive to the temperature. On the other hand, a novel bioreactor from this study may also be useful for the
recombinant protein expression in the field of gene engineering. 相似文献
95.
Feedback network controls photoreceptor output at the layer of first visual synapses in Drosophila
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Zheng L de Polavieja GG Wolfram V Asyali MH Hardie RC Juusola M 《The Journal of general physiology》2006,127(5):495-510
At the layer of first visual synapses, information from photoreceptors is processed and transmitted towards the brain. In fly compound eye, output from photoreceptors (R1-R6) that share the same visual field is pooled and transmitted via histaminergic synapses to two classes of interneuron, large monopolar cells (LMCs) and amacrine cells (ACs). The interneurons also feed back to photoreceptor terminals via numerous ligand-gated synapses, yet the significance of these connections has remained a mystery. We investigated the role of feedback synapses by comparing intracellular responses of photoreceptors and LMCs in wild-type Drosophila and in synaptic mutants, to light and current pulses and to naturalistic light stimuli. The recordings were further subjected to rigorous statistical and information-theoretical analysis. We show that the feedback synapses form a negative feedback loop that controls the speed and amplitude of photoreceptor responses and hence the quality of the transmitted signals. These results highlight the benefits of feedback synapses for neural information processing, and suggest that similar coding strategies could be used in other nervous systems. 相似文献
96.
Reactions of salicyl- and 3,5-dichlorosalicylaldehyde-S-propyl-thiosemicarbazones with salicyl- and 3,5-dichlorosalicylaldehyde in the presence of UO2(CH3COO)2 in different alcohols yielded stable solid complexes corresponding to the general formula [UO2(L)ROH] (R: propyl-, butyl-, pentyl-, and octyl-). The complexes were characterized by means of elemental analysis, IR and 1H NMR spectroscopies. The thermal stabilities of the alcohol solvated complexes were investigated in air and nitrogen atm., and determined their decomposition phases. In the crystal structure of the [UO2(L)(C4H9OH)], the U(VI) centre is seven-coordinated in a distorted pentagonal bipyramidal geometry involving O,O,N,N atoms of two phenolic and two imine groups and one oxygen atom of alcohol molecule in basal plane and two O atoms of dioxo group in apical positions. The title structure is stabilized by one intramolecular interaction of types C-H?Cl and by two intermolecular interactions of types O-H?O and C-H?π (benzene) leading to the molecular chain along the [0 1 0] direction. 相似文献
97.
Jennifer A. Webster J. Raphael Gibbs Jennifer Clarke Weixiong Zhang Peter Holmans Alice Zhao Mona Kaleem Cindy Cuello Leslie Bryden Victoria L. Zismann Keta Joshipura Matthew J. Huentelman Diane Hu-Lince Keith D. Coon David W. Craig John V. Pearson NACC-Neuropathology Group Eric M. Reiman Dietrich Stephan John Hardy Amanda J. Myers 《American journal of human genetics》2009,84(4):445-458
98.
Anti-tubercular agents. Part 3. Benzothiadiazine as a novel scaffold for anti-Mycobacterium activity
Kamal A Reddy KS Ahmed SK Khan MN Sinha RK Yadav JS Arora SK 《Bioorganic & medicinal chemistry》2006,14(3):650-658
In an effort to develop new and more effective therapies to treat tuberculosis, a series of benzothiadiazine 1,1-dioxide derivatives were synthesized and their in vitro activity against Mycobacterium tuberculosis, Mycobacterium avium and Mycobacterium intracellulare was evaluated. One of the compounds, 8c, exhibited potent anti-tubercular activity, particularly for the resistant strains and thus prompted us to investigate its in vivo profile. However, the in vivo testing in a mouse model of tuberculosis infection did not show significant anti-tubercular activity, probably because of its poor bioavailability. 相似文献
99.
Wei Sun Hong Chang Kenji Tsunoda Hassan Musa Yuehui Ma Weijun Guan 《Biochemical genetics》2010,48(5-6):376-384
This study assessed the usefulness of geographic and pairwise genetic distances in the characterization of five sheep populations using 15 microsatellite markers. The average F statistics across loci were F IT = 0.523 ± 0.140, F ST = 0.363 ± 0.131, and F IS = 0.263 ± 0.092. The average heterozygosity was 0.716 ± 0.069, polymorphism information content was 0.691 ± 0.070, and effective number of alleles was 3.736 ± 0.998. Sheep populations clustered into group 1 (Hu and Tong breeds) and group 2 (small-tailed Han, Wadi, and Tan breeds). Reynolds’ distance varied from 0.0062 to 0.0499, and the range of gene flow (N m) was 4.8834–40.0726 among the sheep populations. The results showed that the genetic structure of the five populations was not consistent with their genetic distances, and the population genetic divergence was not linearly related to geographic distance as indicated by a Mantel test (P = 0.7936). 相似文献