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471.
K.B. Kalpana N. Devipriya K. Thayalan Venugopal P. Menon 《Chemico-biological interactions》2010,186(3):267-274
The present study was aimed to evaluate the radioprotective efficacy of dendrodoine analog (DA), an aminothiazole derivative against X-ray radiation-induced cellular damage in cultured human peripheral blood lymphocytes. Different concentrations of DA (2, 4, 6, 8, 10 μg/ml or 6.15, 12.29, 18.44, 24.59, 30.73 μM) were pre-incubated with lymphocytes for 30 min prior to irradiation [4 Gy] and the micronuclei (MN) scoring and comet assay were performed to fix the effective concentration of DA against 4 Gy irradiation-induced cellular damage. The results indicated that among all the concentrations, 6 μg/ml concentration of DA showed optimum protection by effectively decreasing the MN frequencies and comet attributes. Based on the above results, 6 μg/ml concentration of DA was fixed as the effective dose to further investigate its radioprotective efficacy. This was carried out by pre-incubating the lymphocytes with 6 μg/ml concentration of DA followed by exposure of the lymphocytes to different doses (1, 2, 3 and 4 Gy) of radiation and investigating the radiation-induced genetic damage (MN, comet assay, DNA fragmentation assay) and biochemical changes (changes in the level of enzymic and non-enzymic antioxidants, lipid peroxidation). The results indicated a dose-dependent increase in both genetic damage and thiobarbituric acid reactive substances (TBARS), accompanied by a significant decrease in the antioxidant status in the irradiated groups compared to DA treated groups which modulated the toxic effects through its antioxidant potential. Thus the current study shows DA to be an effective radioprotector against X-ray radiation induced in vitro cellular damage in lymphocytes. 相似文献
472.
Tania Luthra K. Naga Lalitha A. Uma Subhabrata Sen 《Bioorganic & medicinal chemistry》2018,26(18):4996-5005
Diabetes a non-communicable disease occurs either due to the lack of insulin or the inability of the human body to recognize it. The recent data indicated an increase in the trend of people diagnosed with type 2 diabetes mainly due to unhealthy life style. Here in we report a new class of oxindole derivatives 6a-kvia scaffold hopping of known α-glucosidase inhibitors 1–4. When molecular docking was performed against a homology model of α-glucosidase the resulting compound 6d revealed binding interactions comparable to 1–4. The compounds were accessed through a unique condensation-ring opening protocol of pyridofuranone building blocks. Overall the compounds exhibited decent binding to the yeast α-glucosidase, where the most potent compound 6h, inhibited the enzyme with IC50 of 0.6?µM. This was nearly threefold improvement from the original known compounds 1–4, selected to design the newer analogs. The reaction kinetics of 6h indicated competitive inhibition. 相似文献
473.
A study was initiated to categorize the seeds of various wild and cultivar legume varieties on the basis of their relative resistance to the bruchid, C. maculatus, and to correlate the important primary and secondary metabolites (non-protein anti-metabolites) in these seeds to the developmental parameters of the bruchid. In general, the wild seed varities showed greater amount of resistance to the bruchid attack when compared to that of the cultivar varieties. All the cultivar varieties studied showed higher amounts of primary metabolites, namely, proteins, carbohydrates, lipids and free amino acids thus showing a positive correlation between the primary metabolites content and the infestation rate. The wild varieties, however, showed significantly lower amounts of these primary metabolites and consequently a lower level of infestation. The non-protein anti-metabolites such as total phenols, ortho- dihydroxy phenols and tannis were significantly lower in the cultivars. The wild varieties, in contrast, revealed higher amounts of these secondary metabolites showing a negative correlation between these secondary metabolites content and the infestation rate. The study revealed that these non-protein anti-metabolites are important in conferring resistance to the seeds. 相似文献
474.
Attenuation of Marek's disease virus by deletion of open reading frame RLORF4 but not RLORF5a 下载免费PDF全文
Marek's disease (MD) in chickens is caused by the alphaherpesvirus MD virus (MDV) and is characterized by the development of lymphoblastoid tumors in multiple organs. The recent identification and cloning of RLORF4 and the finding that four of six attenuated strains of MDV contained deletions within RLORF4 suggested that it is involved in the attenuation process of MDV. To assess the role of RLORF4 in MD pathogenesis, its coding sequence was deleted in the pRB-1B bacterial artificial chromosome clone. Additionally, RLORF5a was deleted separately to examine its importance for oncogenesis. The sizes of plaques produced by MDV reconstituted from pRB-1BdeltaRLORF5a (rRB-1BdeltaRLORF5a) were similar to those produced by the parental pRB-1B virus (rRB-1B). In contrast, virus reconstituted from pRB-1BDeltaRLORF4 (rRB-1BdeltaRLORF4) produced significantly larger plaques. Replication of the latter virus in cultured cells was higher than that of rRB-1B or rRB-1BdeltaRLORF5a using quantitative PCR (qPCR) assays. In vivo, both deletion mutants and rRB-1B replicated at comparable levels at 4, 7, and 10 days postinoculation (p.i.), as determined by virus isolation and qPCR assays. At 14 days p.i., the number of PFU of virus isolated from chickens infected with rRB-1BdeltaRLORF4 was comparable to that from chickens infected with highly attenuated RB-1B and significantly lower than that from rRB-1B-infected birds. The number of tumors and kinetics of tumor production in chickens infected with rRB-1BdeltaRLORF5a were similar to those of P2a chickens infected with rRB-1B. In stark contrast, none of the chickens inoculated with rRB-1BdeltaRLORF4 died up to 13 weeks p.i.; however, two chickens had tumors at the termination of the experiment. The data indicate that RLORF4 is involved in attenuation of MDV, although the function of RLORF4 is still unknown. 相似文献
475.
Maria Angela M. Marques Marcia Berrêdo-Pinho Thabatta L. S. A. Rosa Venugopal Pujari Robertha M. R. Lemes Leticia M. S. Lery Carlos Adriano M. Silva Ana Carolina R. Guimar?es Georgia C. Atella William H. Wheat Patrick J. Brennan Dean C. Crick John T. Belisle Maria Cristina V. Pessolani 《Journal of bacteriology》2015,197(23):3698-3707
476.
477.
Object
Antiangiogenic treatments are beginning to give promising outcomes in many vascular diseases including tumor angiogenesis. In this current study the antiangiogenic and pro-apoptotic actions of α1(IV)NC1 and its N- and C- peptides α1S1(IV)NC1, α1S2(IV)NC1 were investigated in-vitro and in-vivo.Study Method
Endothelial cells (ECs) were treated with α1(IV)NC1, α1S1(IV)NC1, α1S2(IV)NC1 and in-vitro proliferation, migration, tube formation and apoptotic assays were executed. FasL, Fas, Caspase-8, -3 and PARP activations were studied using immunoblotting analysis using specific antibodies. Also the in-vivo antiangiogenic and pro-apoptotic effects were tested using α1(IV)NC1 in a mice model.Results
Like α1(IV)NC1, its N- and C- terminal α1S2(IV)NC1 and α1S1(IV)NC1 domains posses anti-proliferative, pro-apoptotic activity and inhibit ECs migration and tube formation in-vitro. Both α1S1(IV)NC1 and α1S2(IV)NC1 domains promote apoptosis by activating FasL and down stream apoptotic events including activation of caspase-8, -3 and PARP cleavage in a dose dependent manner in-vitro in ECs. Tumors in mice showed apoptotic TUNEL positive microvasculature upon α1(IV)NC1 treatment, indicating inhibition of tumor angiogenesis and tumor growth. Further, the antitumor activity of α1(IV)NC1 was abrogated when caspase-3 inhibitor was used. These results conform additional properties of α1(IV)NC1 as an endogenous angioinhibitor that induces apoptosis in-vitro and in-vivo by activating FasL mediated caspase-3.Significance
α1(IV)NC1 and its N- and C- terminal α1S1(IV)NC1 and α1S2(IV)NC1 domains also posses pro-apoptotic and angioinhibitory activity in-vitro and in-vivo. α1(IV)NC1 regulates tumor angiogenesis by activating FasL mediated apoptosis in-vitro and in-vivo. These results demonstrate that α1(IV)NC1 and its peptides inhibit neo-vascular diseases. 相似文献478.
479.
G. Ashok Kumar Sushil K. Jalali T. Venkatesan Richard Stouthamer P. Niranjana Y. Lalitha 《Biological Control》2009,49(3):207-213
ITS-2-RFLP method was employed to distinguish 12 different trichogrammatids consisting of indigenous and exotic species such as Trichogrammatoidea armigera and Tr. bactrae, Trichogramma achaeae, T. chilonis, T. japonicum, T. embryophagum, T. pretiosum (Thelytokous Form—TF), T. brassicae, T. dendrolimi, T. evanescens and T. mwanzai. ITS-2 region was amplified; complete ITS-2 sequences of nine species were deposited in Genbank. The size of the amplified product ranged from 500 to 900 bp. Restriction enzyme digestion of ITS-2 region showed different banding profiles for these 12 species. Dichotomous keys using the size of the ITS-2 product and the restriction fragment length polymorphism for the enzymes (EcoRI, MseI, MvaI, and TaqI) allowed quick species identification of these trichogrammatids. 相似文献
480.
Laurence P. Clarke Robert J. Nordstrom Huiming Zhang Pushpa Tandon Yantian Zhang George Redmond Keyvan Farahani Gary Kelloff Lori Henderson Lalitha Shankar James Deye Jacek Capala Paula Jacobs 《Translational oncology》2014,7(1):1-4
The purpose of this editorial is to provide a brief history of National Institutes of Health National Cancer Institute (NCI) workshops as related to quantitative imaging within the oncology setting. The editorial will then focus on the recently supported NCI initiatives, including the Quantitative Imaging Network (QIN) initiative and its organizational structure, including planned research goals and deliverables. The publications in this issue of Translational Oncology come from many of the current members of this QIN research network. 相似文献