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101.
Xiang R Liu Y Zhu L Dong W Qi Y 《Apoptosis : an international journal on programmed cell death》2006,11(11):1923-1932
It has been well established that FADD plays a critical role in the membrane bound death-inducing signaling complexes. Herein,
we report that endogenous FADD could interact with ectopic or endogenous RTN3/HAP. ER-bound RTN3 protein recruited endogenous
FADD to the ER membrane and subsequently initiated caspase-8 cascade, including activation of caspase-8, processing of Bid
and release of cytochrome c from mitochondria. Furthermore, we demonstrated that endogenous FADD was recruited by ER-bound endogenous RTN3 to the ER
membrane under the tunicamycin stimulation. The dominant negative form of FADD containing DD could abolish these RTN3 generated
events in the caspase-8 cascade. Moreover, we found that RTN3 induced caspase-9 processing was only partially resulted from
caspase-8 activation (data unshown), indicating that multiple caspase cascades participated in the apoptosis from RTN3 over-expression.
Furthermore, NogoB/ASY, a homologue of RTN3 and a potential RTN3 interacting protein, also associated with FADD and induced
cytochrome c release in a FADD dependent manner.
Rong Xiang and Yingle Liu equal contribution to this work. 相似文献
102.
H9N2 influenza viruses have been circulating worldwide in multiple avian species and have repeatedly infected humans to cause typical disease. The continued avian-to-human interspecies transmission of H9N2 viruses raises concerns about the possibility of viral adaption with increased virulence for humans. To investigate the genetic basis of H9N2 influenza virus host range and pathogenicity in mammals, we generated a mouse-adapted H9N2 virus (SD16-MA) that possessed significantly higher virulence than wide-type virus (SD16). Increased virulence was detectable after 8 sequential lung passages in mice. Five amino acid substitutions were found in the genome of SD16-MA compared with SD16 virus: PB2 (M147L, V250G and E627K), HA (L226Q) and M1 (R210K). Assessments of replication in mice showed that all of the SD16-MA PB2, HA and M1 genome segments increased virus replication; however, only the mouse-adapted PB2 significantly increased virulence. Although the PB2 E627K amino acid substitution enhanced viral polymerase activity and replication, none of the single mutations of mouse adapted PB2 could confer increased virulence on the SD16 backbone. The combination of M147L and E627K significantly enhanced viral replication ability and virulence in mice. Thus, our results show that the combination of PB2 amino acids at position 147 and 627 is critical for the increased pathogenicity of H9N2 influenza virus in mammalian host. 相似文献
103.
Rondeau G McClelland M Nguyen T Risques R Wang Y Judex M Cho AH Welsh J 《Nucleic acids research》2005,33(11):e100
Low abundance mRNAs are more difficult to examine using microarrays than high abundance mRNAs due to the effect of concentration on hybridization kinetics and signal-to-noise ratios. This report describes the use of low complexity representations (LCRs) of mRNA as the targets for cDNA microarrays. Individual sequences in LCRs are more highly represented than in the mRNA populations from which they are derived, leading to favorable hybridization kinetics. LCR targets permit the measurement of abundance changes that are difficult to measure using oligo(dT) priming for target synthesis. An oligo(dT)-primed target and three LCRs detect twice as many differentially regulated genes as could be detected by the oligo(dT)-primed target alone, in an experiment in which serum-starved fibroblasts responded to the reintroduction of serum. Thus, this target preparation strategy considerably increases the sensitivity of cDNA microarrays. 相似文献
104.
Haining Yu Shasha Cai Jiuxiang Gao Chen Wang Xue Qiao Hui Wang Lan Feng Yipeng Wang 《Biochemistry. Biokhimii?a》2016,81(2):152-162
Trypsins are key proteins important in animal protein digestion by breaking down the peptide bonds on the carboxyl side of lysine and arginine residues, hence it has been used widely in various biotechnological processes. In the current study, a full-length cDNA library with capacity of 5·105 CFU/ml from the duck (Anas platyrhynchos) was constructed. Using express sequence tag (EST) sequencing, genes coding two trypsins were identified and two full-length trypsin cDNAs were then obtained by rapid-amplification of cDNA end (RACE)-PCR. Using Blast, they were classified into the trypsin I and II subfamilies, but both encoded a signal peptide, an activation peptide, and a 223-a.a. mature protein located in the C-terminus. The two deduced mature proteins were designated as trypsin-IAP and trypsin-IIAP, and their theoretical isoelectric points (pI) and molecular weights (MW) were 7.99/23466.4 Da and 4.65/24066.0 Da, respectively. Molecular characterizations of genes were further performed by detailed bioinformatics analysis. Phylogenetic analysis revealed that trypsin-IIAP has an evolution pattern distinct from trypsin-IAP, suggesting its evolutionary advantage. Then the duck trypsin-IIAP was expressed in an Escherichia coli system, and its kinetic parameters were measured. The three dimensional structures of trypsin-IAP and trypsin-IIAP were predicted by homology modeling, and the conserved residues required for functionality were identified. Two loops controlling the specificity of the trypsin and the substrate-binding pocket represented in the model are almost identical in primary sequences and backbone tertiary structures of the trypsin families. 相似文献
105.
Objective
The current study explored the correlation of Helicobacter pylori and the polymorphisms of human leukocyte antigen II (HLA-II) alleles with Graves disease (GD).Methods
A total of 216 patients with GD were recruited. 102 healthy volunteers constituted the control group. Levels of H. pylori immunoglobulin G (IgG) antibodies and H. pylori cytotoxin-associated gene A (CagA) IgG antibodies were detected using enzyme-linked immunosorbent assays. Molecular typing of the HLA-II alleles was conducted using polymerase chain reaction with sequence specific primers.Results
H. pylori, particularly CagA-positive strains, HLA-DQA1*0201, and HLA-DQA1*0501 were associated with GD (P = 0.015, OR = 1.811; P = 0.000, OR = 3.085; P = 0.000, OR = 0.315; and P = 0.004, OR = 2.844, respectively). Patients with CagA-positive H. pylori and negative HLA-DQA1*0201 or positive HLA-DQA1*0501 were more likely exposed to GD compared with those with only one of these indices.Conclusion
CagA-positive H. pylori, negative HLA-DQA1*0201, or positive HLA-DQA1*0501 may increase the risk of GD. 相似文献106.
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109.
Alterations in leaf trichomes, stomatal characteristics and epidermal cellular features were investigated in micropropagated
rhubarb (Rheum rhaponticum L.) PC49. The results showed that micropropagated regenerants had produced significantly lower stomatal index, but larger
epidermal cell size than conventional plants. In addition, altered trichome morphology and abnormal stomata, e.g. twin-stomata
were constantly noted only in micropropagated plants. The microscopic observation demonstrated a substantially larger intercellular
space in palisade and mesophyll only in leaves of micropropagated plants. But the results showed no difference in chloroplast
number and chlorophyll content between micropropagated and conventional plants. All the abnormalities suggest somaclonal variation
may have occurred in micropropagated rhubarb PC49. 相似文献
110.
Xu Q Zhang P Hu C Liu X Qi Y Liu Y 《Journal of biochemistry and molecular biology》2006,39(4):406-411
Signaling lymphocyte activation molecule (SLAM; also known as CD150) is a newly identified cellular receptor for measles virus (MV). The interaction between MV Haemagglutin (MVH) and SLAM is an initial step for MV entry. We have identified several novel SLAM binding sites at residues S429, T436 and H437 of MVH protein and MVH mutants in these residues dramatically decrease the ability to interaction with the cell surface SLAM and fail to coprecipitation with SLAM in vivo as well as malfunction in syncytium formation. At the same time, K58, S59 and H61 of SLAM was also identified to be critical for MVH and SLAM binding. Further, these residues may be useful targets for the development of measles therapy. 相似文献