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21.
Pratichi Singh Arthi Venkatesan Parasuraman Padmanabhan Balazs Gulyas Febin Prabhu Dass J 《Journal of cellular biochemistry》2020,121(1):534-544
Hepatitis C virus (HCV) infection is among the leading causes of hepatocellular carcinoma and liver cirrhosis globally, with a high economic burden. The disease progression is well established, but less is known about the spontaneous HCV infection clearance. This study tries to establish the relationship between codon biasness and expression of HCV clearance candidate genes in normal and HCV infected liver tissues. A total of 112 coding sequences comprising 151 679 codons were subjected to the computation of codon indices, namely relative synonymous codon usage, an effective number of codon (Nc), frequency of optimal codon, codon adaptation index, codon bias index, and base compositions. Codon indices report of GC3s, GC12, hydropathicity, and aromaticity implicates both mutational and translational selection in the candidate gene set. This was further correlated with the differentially expressed genes among the selected genes using BioGPS. A significant correlation is observed between the gene expression of normal liver and cancerous liver tissues with codon bias (Nc). Gene expression is also correlated with relative codon bias values, indicating that CCL5, APOA2, CD28, IFITM1, and TNFSF4 genes have higher expression. These results are quite encouraging in selecting the high responsive genes in HCV clearance. However, there could be additional genes which could also orchestrate the clearance role with the above mentioned first line of defensive genes. 相似文献
22.
S Mathiyazhagan K Kavitha S Nakkeeran G Chandrasekar K Manian P Renukadevi 《Archives Of Phytopathology And Plant Protection》2013,46(3):183-199
Bacillus subtilis (BSCBE4), Pseudomonas chlororaphis (PA23), endophytic P. fluorescens (ENPF1) inhibited the mycelial growth of stem blight pathogen Corynespora casiicola (Berk and Curt)Wei under in vitro. All these bacterial isolates produced both hydroxamate and carboxylate type of siderophores. But the siderophore production was maximum with the isolate ENPF1. Delivering of talc based formulation of BSCBE4 through seedling dip and foliar application effectively reduced stem blight disease incidence and increased the dry matter production under pot culture and field conditions. Application of BSCBE4, PA23 and ENPF1 increased the defense related enzymes such as peroxidase, polyphenol oxidase, chitinase and β-1,3 glucanase in P. amarus up to ten days after challenge inoculation with C. cassicola. Native gel electrophoretic analysis revealed that challenge inoculation of pathogen with BSCBE4 and PA23 induced both peroxidase and polyphnol oxidase isoforms. 相似文献
23.
Venkatesan Suryanarayanan 《Journal of biomolecular structure & dynamics》2013,31(16):4303-4319
p300/CBP Associated Factor (PCAF) bromodomain (BRD), a lysine acetyltransferases, has emerged as a promising drug target as its dysfunction is linked to onset and progression of several diseases like cancer, diabetes, AIDS, etc. In this study, a three featured E-Pharmacophore (ARR) was generated based on acetyllysine mimicking inhibitor of PCAF BRD which is available as co-crystal structure (PDB ID: 5FDZ). It was used for filtering small molecule databases followed by molecular docking and consequently validated using enrichment calculation. The resulted hits were found to be congeners which show the predictive power of E-Pharmacophore hypothesis. Further, Induced Fit Docking method, Binding energy calculation, ADME prediction, Single Point Energy calculation and Molecular Dynamics simulation were performed to find better hits against PCAF BRD. Based on the results, it was concluded that Asn803, Tyr809 and Tyr802 along with a water molecule (HOH1001) plays crucial role in binding with inhibitor. It is also proposed that four hits from Life Chemicals database namely, F2276-0099, F2276-0008, F2276-0104 and F2276-0106 could act as potent drug molecules for PCAF BRD. Thus, the present study is strongly believed to have bright impact on rational drug design of potent and novel congeners of PCAF BRD inhibitors. 相似文献
24.
Marine bacteria from the hull of a ship in the form of biofilms or microfouling were isolated, cultured, and identified by phylogenetic analysis using 16S rDNA sequences. With an average length of 946 bp, all the 16 sequences were classified using the Ribosomal database project (RDP) and were submitted to the National Center for Biotechnology Information. Phylogenetic analysis using 16S rDNA sequences indicated that the 16 strains belonged to the Firmicutes (IK-MB6 Exiguobacterium aurantiacum, IK-MB7 Exiguobacterium arabatum, IK-MB8 Exiguobacterium arabatum, IK-MB9 Jeotgalibacillus alimentarius, IK-MB10 Bacillus megaterium, IK-MB11 Bacillus pumilus, IK-MB12 Bacillus pumilus, IK-MB13 Bacillus pumilus, IK-MB14 Bacillus megaterium), High GC, Gram-positive bacteria (IK-MB2 Micrococcus luteus, IK-MB5 Micrococcus luteus, IK-MB16 Arthrobacter mysorens), G-Proteobacteria (IK-MB3 Halomonas aquamarina, IK-MB15 Halotalea alkalilenta), CFB group bacteria (IK-MB1 Myroides odoratimimus), and Enterobacteria (IK-MB4 Proteus mirabilis). Among the 16 strains, representatives of the Firmicutes were dominant (56.25%) compared to the high GC, Gram-positive bacteria (18.75%), G-Proteobacteria (12.5%), CFB group bacteria (6.25%), and Enterobacteria (6.25%). Analysis revealed that majority of marine species found in marine biofilm are of anthropogenic origin. 相似文献
25.
Corey R. Johnson Suresh Kumar Gorla Mandapati Kavitha Minjia Zhang Xiaoping Liu Boris Striepen Jan R. Mead Gregory D. Cuny Lizbeth Hedstrom 《Bioorganic & medicinal chemistry letters》2013,23(4):1004-1007
Cryptosporidium parvum (Cp) is a potential biowarfare agent and major cause of diarrhea and malnutrition. This protozoan parasite relies on inosine 5′-monophosphate dehydrogenase (IMPDH) for the production of guanine nucleotides. A CpIMPDH-selective N-aryl-3,4-dihydro-3-methyl-4-oxo-1-phthalazineacetamide inhibitor was previously identified in a high throughput screening campaign. Herein we report a structure–activity relationship study for the phthalazinone-based series that resulted in the discovery of benzofuranamide analogs that exhibit low nanomolar inhibition of CpIMPDH. In addition, the antiparasitic activity of select analogs in a Toxoplasma gondii model of C. parvum infection is also presented. 相似文献
26.
Kavitha Sankaranarayanan Anurag Varshney Kavitha Sankaranarayanan Anurag Varshney 《Molecular membrane biology》2013,30(5):389-400
Voltage gated potassium channels are tetrameric membrane proteins, which have a central role in cellular excitability. Human Kv1.4 channels open on membrane depolarization and inactivate rapidly by a ‘ball and chain’ mechanism whose molecular determinants have been mapped to the cytoplasmic N terminus of the channel. Here we show that the other terminal end of the channel also plays a role in channel inactivation. Swapping the C-terminal residues of hKv1.4 with those from two non-inactivating channels (hKv1.1 and hKv1.2) affects the rates of inactivation, as well as the recovery of the channel from the inactivated state. Secondary structure predictions of the hKv1.4 sequence reveal a helical structure at its distal C-terminal. Complete removal or partial disruption of this helical region results in channels with remarkably slowed inactivation kinetics. The ionic selectivity and voltage-dependence of channel opening were similar to hKv1.4, indicative of an unperturbed channel pore. These results demonstrate that fast inactivation is modulated by structural elements in the C-terminus, suggesting that the process involves the concerted action of the N- and C-termini. 相似文献
27.
28.
Objectives
Circulating Fibroblast Growth Factor 21 (FGF21) levels are increased in insulin resistant states such as obesity, type 2 diabetes mellitus and gestational diabetes mellitus (GDM). In addition, GDM is associated with serious maternal and fetal complications. We sought to study human cerebrospinal fluid (CSF) and corresponding circulating FGF21 levels in women with gestational diabetes mellitus (GDM) and in age and BMI matched control subjects. We also assessed FGF21 secretion from GDM and control human placental explants.Design
CSF and corresponding plasma FGF21 levels of 24 women were measured by ELISA [12 GDM (age: 26–47 years, BMI: 24.3–36.3 kg/m2) and 12 controls (age: 22–40 years, BMI: 30.1–37.0 kg/m2)]. FGF21 levels in conditioned media were secretion from GDM and control human placental explants were also measured by ELISA.Results
Glucose, HOMA-IR and circulating NEFA levels were significantly higher in women with GDM compared to control subjects. Plasma FGF21 levels were significantly higher in women with GDM compared to control subjects [234.3 (150.2–352.7) vs. 115.5 (60.5–188.7) pg/ml; P<0.05]. However, there was no significant difference in CSF FGF21 levels in women with GDM compared to control subjects. Interestingly, CSF/Plasma FGF21 ratio was significantly lower in women with GDM compared to control subjects [0.4 (0.3–0.6) vs. 0.8 (0.5–1.6); P<0.05]. FGF21 secretion into conditioned media was significantly lower in human placental explants from women with GDM compared to control subjects (P<0.05).Conclusions
The central actions of FGF21 in GDM subjects maybe pivotal in the pathogenesis of insulin resistance in GDM subjects. The significance of FGF21 produced by the placenta remains uncharted and maybe crucial in our understanding of the patho-physiology of GDM and its associated maternal and fetal complications. Future research should seek to elucidate these points. 相似文献29.
Laura Tardieu Venkatesan Sundaram Andrew O. Adogwa Gary W. Garcia 《Acta zoologica》2020,101(4):384-391
The morphology of the gastrointestinal tract (GI) is a strong indicator of the dietary habits of a species. The goal of this study was to describe the gross and microanatomy of the digestive tract of the neo-tropical opossum (Didelphis marsupialis insularis) and relate them to the animals’ food habits. GI tracts from 12 adult animals were used for this study. Results found the small intestine made up 65.9% of the GI tract, and the stomach was simple with a prominent caecum. Histologically, the oesophageal mucosa was non-keratinized and glands were found throughout the oesophagus. The large intestine showed a great number of goblet cells, the jejunum possessed well-developed villi, and Peyer's patches were absent in the ileum. The absence of keratinization of the epithelial lining of the oesophagus and stomach and a high lymphocytic infiltration throughout the small and large intestine reflected a more carnivorous diet, whereas the presence of a well-developed caecum in the large intestine indicated the ability to digest plant matter. Overall, the morphology of GI tract of D. m. insularis displayed both carnivorous and herbivorous features, allowing us to conclude that it is an omnivorous animal. 相似文献
30.
Kavitha Kothur Louise Wienholt Esther M Tantsis John Earl Sushil Bandodkar Kristina Prelog Fiona Tea Sudarshini Ramanathan Fabienne Brilot Russell C. Dale 《PloS one》2016,11(2)