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31.
John Ludbrook 《Critical reviews in biochemistry and molecular biology》2013,48(5):339-358
The overall goal of this review is to summarize the current body of knowledge about the structure and function of major proteins of Bacillus anthracis and/or similar spore-forming organisms. B. anthracis is a key spore-forming biological threat agent, as well as human and animal Gram-positive bacterial pathogen. The structural information described here is limited to approximately the last 5 years. This information is then related to the role of the selected proteins in pathogenesis and in the possible development of novel vaccine and/or other antimicrobial agents against spore-forming organisms, including anthrax, a disease caused by B. anthracis.Among spore-forming bacteria, Bacillus and Clostridium species are the predominant spore-forming bacilli that cause serious diseases. The biochemical properties and mechanism of catalysis of the novel spore germination protease that degrades small, acid-soluble proteins protecting DNA against damage, a cofactor independent phosphoglycerate mutase, NAD+ synthetase, and the three know B. anthracis toxins, protective antigen, lethal factor, and edema factor are described. The studies described in this work review and unify selected information critical for the prevention of microbial diseases such as anthrax. A strategy for the structure-guided development of new prophylactic and therapeutic agents is discussed. 相似文献
32.
ABSTRACTMethyl green (MG) is an inexpensive, nonproprietary, traditional histological stain for cell nuclei. When bound to DNA and upon excitation with orange-red light, it fluoresces brightly in the far red region. We compared MG with ethidium bromide (EtBr), the conventional stain for DNA in gels, and Serva DNA stain G? (SDsG), a proprietary stain marketed as a safer alternative to EtBr for staining of electrophoresed DNA bands in agarose and polyacrylamide gels. DNA-MG fluorescence was recorded and 2.4 μg/ml MG produced crisp images of electrophoresed DNA after incubation for 10 min. Stain solutions were stable and detection limits for faint bands as well as relative densitometric quantitation were equivalent to EtBr. MG, EtBr and SDsG cost 0.0192, 0.024 and 157.5 US cents/test, respectively. MG is an effective stain for visualizing DNA in agarose and polyacrylamide gels. Its major advantages including low cost, comparable quality of staining, storage at room temperature, photo-resistance and low mutagenic profile outweigh its disadvantages such as staining of tracking dye and requirement for a gel documentation system with a red filter. 相似文献
33.
Kamil Musilek Ondrej Holas Kamil Kuca Daniel Jun Vlastimil Dohnal Veronika Opletalova 《Journal of enzyme inhibition and medicinal chemistry》2013,28(1):70-76
Six AChE monooxime-monocarbamoyl reactivators with an (E)-but-2-ene linker were synthesized using modification of currently known synthetic pathways. Their potency to reactivate AChE inhibited by the nerve agent tabun and insecticide paraoxon was tested in vitro. The reactivation efficacies of pralidoxime, HI-6, obidoxime, K048, K075 and the newly prepared reactivators were compared. According to the results obtained, one reactivator seems to be promising against tabun-inhibited AChE and two reactivators against paraoxon-inhibited AChE. The best results were obtained for bisquaternary substances with at least one oxime group in position four. 相似文献
34.
Daniel C. Capaldi Alessandra Eleuteri Qin Chen Raymond F. Schinazi 《Nucleosides, nucleotides & nucleic acids》2013,32(4):403-416
Abstract The synthesis of pyrimidine nucleosides, cis-N-1-[(2-hydroxymethyl)-1,3-dioxan-5-yl]uracil (4) cis-N-1-[(2-hydroxymethyl)-1,3-dioxan-5-yl]thymine (5) and cis-N-1-[(2-hydroxymethyl)-1,3-dioxan-5-yl]cytosine (6) and their corresponding trans isomers is described. Compound 4 showed modest, selective activity against human immunodeficiency virus in acutely infected primary human lymphocytes. 相似文献
35.
Chang Hyun Oh Lian Jin Liu Joon Hee Hong 《Nucleosides, nucleotides & nucleic acids》2013,32(10):721-733
A novel 3′,4′-dimethyl-5′-norcarbocyclic adenosine phosphonic acid was prepared using acyclic stereoselective route from 4-hydroxybutan-2-one (4). To improve the cellular permeability and enhance the anti-HIV activity of this phosphonic acid, a (bis)SATE phosphonodiester nucleoside prodrug (20) was prepared and its chemical stability was evaluated. The newly synthesized bis(SATE) analogue (20) and its parent nucleoside phosphonic acid (18) were assayed for anti-HIV activity using an in vitro assay system in a CEM cell line. 相似文献
36.
Etsuko Kawashima Yasuhiro Nakanishi Yusuke Terui Hideyuki Tomitori Keiko Kashiwagi Yusuke Ohba 《Nucleosides, nucleotides & nucleic acids》2013,32(4):196-205
Pyrrole polyamide-2′-deoxyguanosine 5′-phosphate hybrid (Hybrid 4) was synthesized and evaluated in terms of the inhibition of mouse mammary carcinoma FM3A cell growth. Hybrid 4 was found to exhibit dose-dependent inhibition of cell growth. 相似文献
37.
The discovery of threosyl phosphonate nucleoside (PMDTA, EC50 = 2.53 μM) as a potent anti-HIV agent has led to the synthesis and biological evaluation of 5 ′-deoxyversions of threosyl phosphonate nucleosides from 1,4-dihydroxy-2-butene. The synthesized nucleoside phosphonic acid analogues 14 and 19 were tested for anti-HIV activity as well as cytotoxicity. The adenine analogue 14 exhibits moderate in vitro anti-HIV-1 activity (EC50 = 12.6 μM). 相似文献
38.
On the basis of the discovery that the threosyl nucleoside phosphonate PMDTA is a potent anti-HIV compound, we synthesized several 4′-trifluoromethyl-5′-deoxyapiosyl nucleoside phosphonic acids and evaluated their anti-HIV activity. An efficient synthetic route was optimized, starting from an α-trifluoromethyl-α,β-unsaturated ester. Glycosylation of the purine nucleosidic bases with a glycosyl donor yielded modified nucleoside intermediates, which were then phosphonated and hydrolyzed to provide the targeted nucleoside analogs. Once synthesized, the anti-HIV and cytotoxic activities of each analog were evaluated. None of the analogs showed significant anti-HIV activity at concentrations up to 100 μM. 相似文献
39.
Yuan Yuan Zhang Jun Hong Liu Yuan ming Zhou Yu Yan Zhang Ying Liu Ting Yun Gong Jing Wang 《Process Biochemistry》2013,48(8):1119-1125
A new two-phase kinetic model of sporulation of Clonostachys rosea in a new solid-state fermentation (SSF) reactor was proposed. The model including exponential and logistic models was applied to study the simultaneous effect of temperature, initial moisture content, medium thickness and surface porosity of the plastic membrane on C. rosea sporulation. The model fits experimental data very well and allows accurate predictions of spore production. The maximum spore production achieved 3.360 × 1010 (spores/gDM), about 10 times greater than that in traditional SSF reactor(data not shown). The new reactor can provide two times sporulation surface area. Moisture content can be adjusted by changing the surface porosity to meet the spore production. Two mixings carried out during fermentation makes medium loose and results in a mass of new sporulation surface area. Therefore, the new SSF reactor would have great potential for application in bulk spore production of fungal biocontrol agents. 相似文献
40.
目的:设计并合成抗肿瘤药物帕玛度胺的3位N取代的新型类似物。方法:从3-硝基邻苯二甲酸(2)和N-(叔丁氧羰基).L-谷氨酰胺(4)出发,经过六步反应得到目标化合物。3-硝基邻苯二甲酸(2)经脱水制得3-硝基邻苯二甲酸酐(3)。用N-(叔丁氧羰基)-L-谷氨酰胺(4)经闭环、脱保护制得3-氨基-2,6-哌啶二酮三氟乙酸盐(6)。4与6经缩合、钯碳催化氢化制得免疫调节剂Pomalidomide(8),(8)经过酰化得到3-乙酰氨基-N-(2,6-二氧代-3-哌啶基)邻苯二甲酰亚胺(1)。以(4)计总收率约34.9%。结果:得到3-乙酰氨基-N-(2,6-二氧代-3-哌啶基)-邻苯二甲酰亚胺(1),应用于细胞活性测试。结论:改进了帕玛度胺的合成工艺,得到了3位N乙酰化的新型帕玛度胺类似物(1),初步研究显示(1)的生物活性与帕玛度胺接近。 相似文献