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111.
The incorporation of [14C]-acetate, [14C]-mevalonate and [14C]-desmosterol into cholesterol in the muscle mitochondria of the brown shrimpPenaeus aztecus (Ives) is more as compared to that in hepatopancreas. [14C]-Desmosterol is more efficiently incorporated into cholesterol in comparison with [14C]-acetate. The muscle mitochondria from males incorporated more [14C]-mevalonate into cholesterol than those from females, while the converse is true in the hepatopancreatic mitochondria. 相似文献
112.
Kaushik Ghosh Rajagopal Chattopadhyaya 《Journal of biomolecular structure & dynamics》2013,31(4):557-567
Abstract The circular dichroism spectra of three different purified carboxy terminal fragments 93–236, 112–236 and 132–236 of the bacteriophage γ cI repressor have been measured and compared with those of the intact repressor and the amino terminal fragment 1–92. All three carboxy terminal fragments contain mostly β-strands and loops, a minor helix content increasing with the size of the fragment, showing that the 93–131 region previously called a hinge is structured. Fourier transformed infrared spectra also showed that fragment 93–236 contains α-helices, β-sheets and turns but fragment 132–236 contains no detectable α-helix, only β-sheets and turns. Papain is known to cleave the γ repressor, but it is shown here that it cannot cleave the operator-bound repressor dimer. For the 132–236 fragment, both the wt and the SN228 mutant previously shown to be dimerization defective in the intact, gave similar dimerization properties as investigated by HPLC at 2 to 100 µM protein concentration, with a KD of 13.2 µM and 19.1 µM respectively. The papain cleavage for wt and SN228 proceed at equal rates for the first cleavage at 92–93; however, the subsequent cleavages are faster for SN228. The three Cys residues in the 132–236 fragment were found to be unreactive upon incubation with DTNB, indicating the thiol sulfur atoms are buried in the repressor carboxy terminal domain. Denaturation of the 132–236 fragment studied by tryptophan fluorescence shows two transitions centered at 1.5 M and 4.5 M of urea. 相似文献
113.
The fluorescent probe erythrosine 5′-iodoacetamide (ER) binds to mitochondrial NADH-CoQ reductase (Complex-I) accompanied by an enhancement of the fluorescence intensity. The binding of the CoQ analogue, 2,3-dimethoxy-5-methyl-6-decyl-1,4-benzoquinone (DB), decreased the fluorescence intensity of the ER:Complex-I system. The ‘site 1’ inhibitor rotenone did not decrease the fluorescence intensity showing the non-identical nature of the binding sites of DB and rotenone. Also, the reduced form of DB did not decrease the fluorescence intensity. The decrease of the fluorescence intensity by DB was shown to be due to the removal of bound ER by DB. The rapid kinetics of ER binding was studied by temperature-jump relaxation. While DB caused complete elimination of the relaxation process in the ER:Complex-I system, rotenone caused only a decrease in the relaxation rate, suggesting conformational change. The relaxation rate showed a pH dependence with a maximum around pH 7.5. 相似文献
114.
Ravichandran Yesuvadian Janarthanan Krishnamoorthy Ayyalusamy Ramamoorthy Anirban Bhunia 《Biochemical and biophysical research communications》2014
Recently, γ-secretase modulators (GSM) have been shown to interact directly with the amyloid precursor protein (APP) and simultaneously inhibit the activity of the Presenilin domain of γ-secretase. A clear understanding of the molecular recognition pathways by which GSM can target both γ-secretase and Aβ precursor protein can lead to the development of more effective inhibitors. To examine whether this direct interaction with APP affects the downstream Aβ fibril formation, we chose to investigate three different molecules in this study: Sulindac sulfide, Semagacestat and E2012 from the class of generation I GSMs, γ-secretase inhibitors (GSI), and generation II GSM molecules, respectively. Firstly, through NMR based ligand titration, we identified that Sulindac sulfide and Semagacestat interact strongly with Aβ40 monomers, whereas E2012 does not. Secondly, using saturation transfer difference (STD) NMR experiments, we found that all three molecules bind equally well with Aβ40 fibrils. To determine if these interactions with the monomer/fibril lead to a viable inhibition of the fibrillation process, we designed an NMR based time-dependent assay and accurately distinguished the inhibitors from the non-inhibitors within a short period of 12 h. Based on this pre-seeded fibril assay, we conclude that none of these molecules inhibit the ongoing fibrillation, rather ligands such as Semagacestat and E2012 accelerated the rate of aggregation. 相似文献
115.
Summary When a leguminous crop like cowpea was included in a crop rotation of Ganga 5 maize, CO 7 ragi and CO 2 cowpea, the total nitrogen content in the soil was considerably increased even in the unfertilized plots. The leguminous crop fixed atmospheric nitrogen at the rate of 205 kg N/hectare/year. Potassium did not influence the status whereas phosphorus, over a background of N, improved it. Considerable quantity of N fixed was observed to have been redistributed in the soil which depended on the fertilization pattern. 相似文献
116.
Background
Endocytosis is a key regulator of growth factor signaling pathways. Recent studies showed that the localization to endosomes of intracellular mediators of growth factor signaling may be required for their function. Although there is substantial evidence linking endocytosis and growth factor signaling in cultured cells, there has been little study of the endosomal localization of signaling components in intact tissues or organs. 相似文献117.
Ramansu Goswami Suprabhat Mukherjee Vipin Singh Rana Dhira Rani Saha Rajagopal Raman Pratap Kumar Padhy 《Geomicrobiology journal》2013,30(1):17-26
Bengal Basin is known for severe arsenic contamination. In the present study, we have isolated six bacteria from the arsenic contaminated surface water of Bengal Basin. 16S rDNA sequence analysis identified them as Microbacterium oleivorans, Acinetobacter soli, Acinetobacter venetianus, Acinetobacter junii, Acinetobacter baumannii, Acinetobacter calcoaceticus. All the isolates possess arsenic accumulation potential and high molecular weight plasmid (>10 kb). PCR amplification indicated the presence of arsenic-resistance genes (arsB and aoxB) either in the genome or plasmid or in both in the isolated bacteria (except in Acinetobacter venetianus). Exposure to arsenic affected bacterial growth and induced alteration in cytoplasmic membrane integrity. 相似文献
118.
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120.
Mark A. Seefeld Hong Lin Joerg Holenz Dave Downie Brian Donovan Tingting Fu Kishore Pasikanti Wei Zhen Matthew Cato Khuram W. Chaudhary Pat Brady Tania Bakshi Dwight Morrow Sridharan Rajagopal Swapan Kumar Samanta Naveena Madhyastha Bharathi Mohan Kuppusamy Robert W. Dougherty Yasuji Matsuoka 《Bioorganic & medicinal chemistry letters》2018,28(23-24):3793-3797
Neuronal voltage-gated potassium channels, KV7s, are the molecular mediators of the M current and regulate membrane excitability in the central and peripheral neuronal systems. Herein, we report novel small molecule KV7 openers that demonstrate anti-seizure activities in electroshock and pentylenetetrazol-induced seizure models without influencing Rotarod readouts in mice. The anti-seizure activity was determined to be proportional to the unbound concentration in the brain. KV7 channels are also expressed in the bladder smooth muscle (detrusor) and activation of these channels may cause localized undesired effects. Therefore, the impact of individual KV7 isoforms was investigated in human detrusor tissue using a panel of KV7 openers with distinct activity profiles among KV7 isoforms. KCNQ4 and KCNQ5 mRNA were highly expressed in detrusor tissue, yet a compound that has significantly reduced activity on homomeric KV7.4 did not reduce detrusor contraction. This may suggest that the homomeric KV7.4 channel plays a less significant role in bladder contraction and further investigation is needed. 相似文献