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1.
G J Ebrahim 《BMJ (Clinical research ed.)》1987,295(6608):1222-1223
2.
Kroczynska B Evangelista CM Samant SS Elguindi EC Blond SY 《The Journal of biological chemistry》2004,279(12):11432-11443
The murine tumor cell DnaJ-like protein 1 or MTJ1/ERdj1 is a membrane J-domain protein enriched in microsomal and nuclear fractions. We previously showed that its lumenal J-domain stimulates the ATPase activity of the molecular chaperone BiP/GRP78 (Chevalier, M., Rhee, H., Elguindi, E. C., and Blond, S. Y. (2000) J. Biol. Chem. 275, 19620-19627). MTJ1/ERdj1 also contains a large carboxyl-terminal cytosolic extension composed of two tryptophan-mediated repeats or SANT domains for which the function(s) is unknown. Here we describe the cloning of the human homologue HTJ1 and its interaction with alpha(1)-antichymotrypsin (ACT), a member of the serine proteinase inhibitor (serpin) family. The interaction was initially identified in a two-hybrid screening and further confirmed in vitro by dot blots, native electrophoresis, and fluorescence studies. The second SANT domain of HTJ1 (SANT2) was found to be sufficient for binding to ACT, both in yeast and in vitro. Single tryptophan-alanine substitutions at two strictly conserved residues significantly (Trp-497) or totally (Trp-520) abolished the interaction with ACT. SANT2 binds to human ACT with an intrinsic affinity equal to 0.5 nm. Preincubation of ACT with nearly stoichiometric concentrations of SANT2 wild-type but not SANT2: W520A results in an apparent loss of ACT inhibitory activity toward chymotrypsin. Kinetic analysis indicates that the formation of the covalent inhibitory complex ACT-chymotrypsin is significantly delayed in the presence of SANT2 with no change on the catalytic efficiency of the enzyme. This work demonstrates for the first time that the SANT2 domain of MTJ1/HTJ1/ERdj1 mediates stable and high affinity protein-protein interactions. 相似文献
3.
Shanil Ebrahim Luis Montoya Wanda Truong Sandy Hsu Mostafa Kamal el Din Alonso Carrasco-Labra Jason W. Busse Stephen D. Walter Diane Heels-Ansdell Rachel Couban Irene Patelis-Siotis Marg Bellman L. Esther de Graaf David J. A. Dozois Peter J. Bieling Gordon H. Guyatt 《PloS one》2012,7(11)
Objectives
To systematically summarize the randomized trial evidence regarding the relative effectiveness of cognitive behavioural therapy (CBT) in patients with depression in receipt of disability benefits in comparison to those not receiving disability benefits.Data Sources
All relevant RCTs from a database of randomized controlled and comparative studies examining the effects of psychotherapy for adult depression (http://www.evidencebasedpsychotherapies.org), electronic databases (MEDLINE, EMBASE, PSYCINFO, AMED, CINAHL and CENTRAL) to June 2011, and bibliographies of all relevant articles.Study Eligibility Criteria, Participants and Intervention
Adult patients with major depression, randomly assigned to CBT versus minimal/no treatment or care-as-usual.Study Appraisal and Synthesis Methods
Three teams of reviewers, independently and in duplicate, completed title and abstract screening, full text review and data extraction. We performed an individual patient data meta-analysis to summarize data.Results
Of 92 eligible trials, 70 provided author contact information; of these 56 (80%) were successfully contacted to establish if they captured receipt of benefits as a baseline characteristic; 8 recorded benefit status, and 3 enrolled some patients in receipt of benefits, of which 2 provided individual patient data. Including both patients receiving and not receiving disability benefits, 2 trials (227 patients) suggested a possible reduction in depression with CBT, as measured by the Beck Depression Inventory, mean difference [MD] (95% confidence interval [CI]) = −2.61 (−5.28, 0.07), p = 0.06; minimally important difference of 5. The effect appeared larger, though not significantly, in those in receipt of benefits (34 patients) versus not receiving benefits (193 patients); MD (95% CI) = −4.46 (−12.21, 3.30), p = 0.26.Conclusions
Our data does not support the hypothesis that CBT has smaller effects in depressed patients receiving disability benefits versus other patients. Given that the confidence interval is wide, a decreased effect is still possible, though if the difference exists, it is likely to be small. 相似文献4.
5.
Kheradmand K Kamali K Fathipour Y Goltapeh EM Ueckermann EA 《Journal of economic entomology》2007,100(4):1098-1103
The free-living mite species Sancassania rodionovi (Zachvatkin) (Acari: Acaridae), is a serious pest of mushrooms in Iran. Studies were conducted to examine the development of this mite in relation to temperature on two mushroom species: Agaricus bisporus Lange (button mushroom) and Pleurotus ostreatus Kummer (oyster mushroom). The developmental time of this acarid mite was studied at eight constant temperatures, ranging from 5 to 40 degrees C, and developmental rates were modeled as a function of temperature. Sancassania rodionovi completed immature development in 17.35 +/- 0.58 and 20.17 +/- 0.88 d at 25 degrees C on button and oyster mushrooms, respectively. When the mite fed on button mushroom, the rate of development increased gradually from 10 to 35 degrees C. Using a linear model, the developmental zero was estimated to be 3.50 degrees C with a thermal constant of 357.14 degree-days. The Logan 10, Briere 1, and Thermodynamic models adequately described the data for this mite and yielded R2 values >0.95; these models provided estimates of optimum temperature for development of 33.244, 32.145, and 32.148 degrees C, respectively. Understanding the influence of temperature on development of S. rodionovi is discussed with respect to pest management in mushroom production. 相似文献
6.
Azari H Osborne GW Yasuda T Golmohammadi MG Rahman M Deleyrolle LP Esfandiari E Adams DJ Scheffler B Steindler DA Reynolds BA 《PloS one》2011,6(6):e20941
Large-scale proliferation and multi-lineage differentiation capabilities make neural stem cells (NSCs) a promising renewable source of cells for therapeutic applications. However, the practical application for neuronal cell replacement is limited by heterogeneity of NSC progeny, relatively low yield of neurons, predominance of astrocytes, poor survival of donor cells following transplantation and the potential for uncontrolled proliferation of precursor cells. To address these impediments, we have developed a method for the generation of highly enriched immature neurons from murine NSC progeny. Adaptation of the standard differentiation procedure in concert with flow cytometry selection, using scattered light and positive fluorescent light selection based on cell surface antibody binding, provided a near pure (97%) immature neuron population. Using the purified neurons, we screened a panel of growth factors and found that bone morphogenetic protein-4 (BMP-4) demonstrated a strong survival effect on the cells in vitro, and enhanced their functional maturity. This effect was maintained following transplantation into the adult mouse striatum where we observed a 2-fold increase in the survival of the implanted cells and a 3-fold increase in NeuN expression. Additionally, based on the neural-colony forming cell assay (N-CFCA), we noted a 64 fold reduction of the bona fide NSC frequency in neuronal cell population and that implanted donor cells showed no signs of excessive or uncontrolled proliferation. The ability to provide defined neural cell populations from renewable sources such as NSC may find application for cell replacement therapies in the central nervous system. 相似文献
7.
Hanneke Vlaming Tibor van Welsem Erik L de Graaf David Ontoso AF Maarten Altelaar Pedro A San-Segundo Albert JR Heck Fred van Leeuwen 《EMBO reports》2014,15(10):1077-1084
Histone H2B ubiquitination is a dynamic modification that promotes methylation of histone H3K79 and H3K4. This crosstalk is important for the DNA damage response and has been implicated in cancer. Here, we show that in engineered yeast strains, ubiquitins tethered to every nucleosome promote H3K79 and H3K4 methylation from a proximal as well as a more distal site, but only if in a correct orientation. This plasticity indicates that the exact location of the attachment site, the native ubiquitin-lysine linkage and ubiquitination cycles are not critical for trans-histone crosstalk in vivo. The flexibility in crosstalk also indicates that other ubiquitination events may promote H3 methylation. 相似文献
8.
Effect of neohesperidin dihydrochalcone on the activity and stability of alpha‐amylase: a comparative study on bacterial,fungal, and mammalian enzymes 下载免费PDF全文
Elaheh Kashani‐Amin Azadeh Ebrahim‐Habibi Bagher Larijani Ali Akbar Moosavi‐Movahedi 《Journal of molecular recognition : JMR》2015,28(10):605-613
Neohesperidin dihydrochalcone (NHDC) was recently introduced as an activator of mammalian alpha‐amylase. In the current study, the effect of NHDC has been investigated on bacterial and fungal alpha‐amylases. Enzyme assays and kinetic analysis demonstrated the capability of NHDC to significantly activate both tested alpha‐amylases. The ligand activation pattern was found to be more similar between the fungal and mammalian enzyme in comparison with the bacterial one. Further, thermostability experiments indicated a stability increase in the presence of NHDC for the bacterial enzyme. In silico (docking) test locates a putative binding site for NHDC on alpha‐amylase surface in domain B. This domain shows differences in various alpha‐amylase types, and the different behavior of the ligand toward the studied enzymes may be attributed to this fact. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
9.
10.
Ebrahim Eskandari-Nasab Seyed-Shahab-adin Hasani Majid Naderi Simin Sadeghi-Bojd Mohsen Taheri 《Nucleosides, nucleotides & nucleic acids》2017,36(3):170-180
We examined the possible relationship between three RAGE polymorphisms, ?429C/T, ?374 T/A, and 63-bp deletion, and susceptibility to childhood acute lymphoblastic leukemia (ALL) in an Iranian population. This study included 75 ALL patients and 115 healthy subjects. Genotyping was performed using HEXA-ARMS-polymerase chain reaction. We found no significant association among RAGE gene polymorphisms and the risk for ALL at genotype, allelic and haplotype levels (P > 0.05). The hemoglobin levels were higher in patients with RAGE ?374 TT than in the TA carriers (P = 0.019). Our results demonstrated that the RAGE gene variations were not associated with risk of pediatrics ALL. 相似文献