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1.
Abstract Monoclonal antibodies have been developed and used as specific probe to locate and identify a 29-kDa molecule of axenic Entamoeba histolytica trophozoites. Monoclonal antibody produced by clone C8 (MoAb C8) strongly agglutinated the amoebic trophozoites. THe immunofluorescence of live E. histolytica trophozoites and surface fluorescence of acetone-fixed trophozoites by MoAb C8 indicated existence of a 29-kDa molecule on surface-associated plasma membrane of E. histolytica . The monoclonal antibody belonged to IgG1 isotype. The prior treatment of E. histolytica trophozoites with MoAb C8 resulted in significant ( P < 0.01) reduction in adherence of amoebic trophozoites to cultured Chinese Hamster Ovary cells and significant ( P < 0.01) reduction in cytotoxicity to cultured Baby Hamster Kidney cells. Pretreatment of amoebic trophozoites with MoAb C8 prior to cultivation in TPS-1 medium resulted in significant ( P < 0.01) reduction in growth of the parasite. Thus, the data suggested that the surface-exposed 29-kDa molecule may be one of the receptors involved in E. histolytica host cell interactions and may possibly modulate amoebic disease processes. 相似文献
2.
The development of a sensitive and specific enzyme immunoassay for GA3 is reported. This method was based on the use of peroxidase labelled GA3 and immobilized antibodies. In order to obtain a rapid immunoassay, several steps of purification were analyzed to show their necessity. Barley seed extracts were assayed at different steps of purification to exhibit the effect of extract components on the assay. It was demonstrated that HPLC had to be performed when a selective quantitation of GA3 was required. This assay allowed GA3 to be measured with reproducibility as its unmethylated form and the quantitation of GA3 in barley seeds with this enzyme immunoassay was correlated to a GC-MS method.Abbreviations GA3
gibberellin A3
- EIA
enzyme immunoassay
- DMF
dimethylformamide
- TEA
tri(n)ethylamine
- BSA
bovine serum albumin
- OVA
ovalbumine
- ECF
ethylchloroformate
- PB
phosphate buffer 相似文献
3.
Natural antibodies to interferon-gamma 总被引:3,自引:0,他引:3
Natural antibodies to interferon (IFN)-γ were detected in the serum of virus-infected patients and also, at a low titre, in
the serum of healthy subjects. The increased titre of antibodies to IFN-γ in the sera of virus-infected patients, and its
decrease with clinical resolution, indicate that these antibodies are related to viral infection and probably reflect IFN-γ
production as a result of antigenic stimulationin vivo. Natural antibodies to IFN-γ were affinity purified and studied for their capability to interferein vitro with the multiple activities of the lymphokine. Data obtained show that these human anti-IFN-γ antibodies have no inhibitory
effect on the antiviral and antiproliferative activity of IFN-γ and do not interfere with the binding of the lymphokine to
its specific cell receptor. Instead, they can inhibit the expression of HLA-DR antigens induced by IFN-γ on U937 cells and
interfere, in mixed lymphocyte culture, with the proliferation of lymphocytes and the generation of cytotoxic lymphocytes.
Experiments in animal models suggest that natural antibodies to IFN-γ may have a role in the immunoregulatory process limiting
the intensity and/or duration of immune response. As they can interfere only with the immunomodulating activities of IFN-γ,
these antibodies might open up new therapeutic approaches to diseases with evidence of activated cell-mediated immunity. 相似文献
4.
E. Bravo G. Carpinelli E. Proietti F. Belardelli A. Cantafora F. Podo 《FEBS letters》1990,260(2):220-224
The monocarboxylate (pyruvate) transporter from pea (Pisum sativum) mitochondria was identified by means of a specific monoclonal antibody. The antibody blocked pyruvate-dependent oxaloacetate metabolism without interfering with the metabolism of malate, -ketoglutarate, or glycine. The antibody also blocked the pyruvate/pyruvate exchange reaction of the partially purified transporter reconstituted into phospholipid membranes. Using the specific monoclonal antibody, the transporter was identified on Western blots as a minor 19 kDa protein. 相似文献
5.
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7.
Aurélien Sokal Pascal Chappert Giovanna Barba-Spaeth Anais Roeser Slim Fourati Imane Azzaoui Alexis Vandenberghe Ignacio Fernandez Annalisa Meola Magali Bouvier-Alias Etienne Crickx Asma Beldi-Ferchiou Sophie Hue Laetitia Languille Marc Michel Samia Baloul France Noizat-Pirenne Marine Luka Matthieu Mahévas 《Cell》2021,184(5):1201-1213.e14
8.
《Cell》2021,184(22):5593-5607.e18
9.
Johannes F. Scheid Christopher O. Barnes Basak Eraslan Andrew Hudak Jennifer R. Keeffe Lisa A. Cosimi Eric M. Brown Frauke Muecksch Yiska Weisblum Shuting Zhang Toni Delorey Ann E. Woolley Fadi Ghantous Sung-Moo Park Devan Phillips Betsabeh Tusi Kathryn E. Huey-Tubman Alexander A. Cohen Ramnik J. Xavier 《Cell》2021,184(12):3205-3221.e24
10.
J. P. DUBEY 《The Journal of eukaryotic microbiology》1997,44(6):592-602
ABSTRACT. The development of Toxoplasma gondii was studied in mice fed bradyzoites. At one hour after oral inoculation (HAI), bradyzoites were found in cells of the surface epithelium and the lamina propria of the small intestine, primarily the ileum. Division into two tachyzoites was first observed at 18 HA1 in the intestine. At 24 HAI, organisms were also seen in mesenteric lymph nodes. Organisms were first detected in the brain at six days after oral inoculation with bradyzoites (DAI) but not consistently until 10 DAI. Immunohistochemical staining with bradyzoite specific (BAG-5 antigen) anti-serum showed that bradyzoites retained their BAG-5 reactivity even after the first division into two tachyzoites in the intestine at 18 HAL BAG-5 positive organisms were not seen 2–5 DAI. BAG-5 antigens reappeared in T. gondii at 6 DAI. Whole mice and individual tissues of mice fed bradyzoites were bioassayed in cats and mice for the presence of bradyzoites. Feces of cats fed murine tissues were examined for oocyst shedding for short prepatent periods. Bradyzoites were present in the intestines of mice up to 12 HA1 but not at 18 HAI, and tachyzoites and not bradyzoites disseminated to other tissues from the intestine. Bradyzoites were again detected 6 DAI. Using the mouse bioassay, T. gondii was first detected in peripheral blood at 24 HA1 and more consistently at 48 HAL Using a pepsin-digestion procedure and mouse bioassay, organisms were demonstrated in many tissues of mice 15 and 49 DAI. 相似文献