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101.
To study the novel functionalized heterocyclic molecules with highly potential biological activity, two series of heterocyclic lactam derivatives containing the piperonyl moiety were designed and synthesized. The newly obtained compounds have been identified on the basis of analytical spectral data, including 1H NMR, 13C NMR, and ESI-MS. The target compounds were evaluated for their potential antifungal activities in vitro against twelve species of the plant pathogen fungi (Sclerotinia sclerotiorum, Rhizoctonia solani, Rap Sclerotinia stemrot, Fusarium graminearum, Phomopsis adianticola, Pestallozzia theae, Pestalotiopsis guepinii, Alternaria tenuis Nees, Monilinia fructicola, Colletotrichum gloeosporioides, Phytophthora capsici, Magnaporthe oryzae). Preliminary bioassays suggested that all prepared compounds I114 displayed broad-spectrum and moderate antifungal activities compared with the positive control hymexazol, especially for Sclerotinia sclerotiorum, Rap Sclerotinia stemrot, and Monilinia fructicola. In particular, the inhibition rate of compound I9 exhibited good inhibition activity reached 95.16% against Sclerotinia sclerotiorum, and compounds I5, I12 against Phytophthora capsici were 93.44%, 91.25%. Further studies revealed that compounds I5 (IC50 = 19.13 µM) and I12 (IC50 = 9.12 µM) exhibited obviously antifungal activities against Phytophthora capsici, which were better than that of commercial agricultural fungicide hymexazol (IC50 = 325.45 µM). Therefore, these target compounds could be further studied and explored as a lead skeleton for discovery of novel antifungal agents.  相似文献   
102.
By using a new Fragment-Based Virtual Screen strategy, two series of novel FBA-II inhibitors (thiourea derivatives) were de novo discovered based on the active site of fructose-1, 6-bisphosphate aldolase from Cyanobacterial (CyFBA). In comparison, most of the N-(2-benzoylhydrazine-1-carbonothioyl) benzamide derivatives (L14~L22) exhibit higher CyFBA-II inhibitory activities compared to N-(phenylcarbamothioyl) benzamide derivatives (L1~L13). Especially, compound L14 not only shows higher CyFBA-II activity (Ki?=?0.65?μM), but also exhibits most potent in vivo activity against Synechocystis sp. PCC 6803 (EC50?=?0.09?ppm), higher (7-fold) than that of our previous inhibitor (EC50?=?0.6?ppm). The binding modes of compound L14 and CyFBA-II were further elucidated by jointly using DOX computational protocol, MM-PBSA and site-directed mutagenesis assays. The positive results suggest that strategy adopted in this study was promising to rapidly discovery the potent inhibitors with novel scaffolds. The satisfactory algicide activities suggest that the thiourea derivatives is very likely to be a promising lead for the development of novel specific algicides to solve Cyanobacterial harmful algal blooms (CHABs).  相似文献   
103.
Dopamine D1/D2 receptors are important targets for drug discovery in the treatment of central nervous system diseases. To discover new and potential D1/D2 ligands, 17 derivatives of tetrahydroprotoberberine (THPB) with various substituents were prepared by chemical synthesis or microbial transformation using Streptomyces griseus ATCC 13273. Their functional activities on D1 and D2 receptors were determined by cAMP assay and calcium flux assay. Seven compounds showed high activity on D1/D2 receptor with low IC50 values less than 1?µM. Especially, top compound 5 showed strong antagonistic activity on both D1 and D2 receptor with an IC50 of 0.391 and 0.0757?µM, respectively. Five compounds displayed selective antagonistic activity on D1 and D2 receptor. The SAR studies revealed that (1) the hydroxyl group at C-9 position plays an important role in keeping a good activity and small or fewer substituents on ring D of THPBs may also stimulate their effects, (2) the absence of substituents at C-9 position tends to be more selective for D2 receptor, and (3) hydroxyl substitution at C-2 position and the substitution at C-9 position may facilitate the conversion of D1 receptor from antagonist to agonist. Molecular docking simulations found that Asp 103/Asp 114, Ser 107/Cys 118, and Trp 285/ Trp 386 of D1/ D2 receptors are the key residues, which have strong interactions with the active D1/D2 compounds and may influence their functional profiles.  相似文献   
104.
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106.
2,3-Indolinedione derivatives have been identified as a novel class of promising agents for cancer treatment. In this study, eighteen 2,3-indolinedione derivatives were designed and synthesized, and their anticancer activities against mantle cell lymphoma (MCL) cells were evaluated. Most of them exhibited significant antiproliferative activity against the tested cell lines, and compound K5 was the most potent (MCL cellular IC50 = 0.4–0.7 μM). Further, compound K5 could induce cell apoptosis and cell cycle arrest in G2/M phase. Additionally, the results of drug-likeness analysis demonstrated that these novel 2,3-indolinedione derivatives could have potential as novel treatment strategies for MCL.  相似文献   
107.
天然的间苯三酚类化合物来源广泛、结构新颖,具有多种药理活性,是目前天然药物化学的研究热点之一。本文对近十年发现的天然间苯三酚类化合物的化学结构和药理活性的研究进展做了调研和综述,以期对该类化合物进一步的研究提供参考。  相似文献   
108.
气候变化和人类活动是对陆地生态系统碳循环产生重要影响的两个因素,定量评估气候变化与人类活动对植被净初级生产力(NPP)的相对影响,对深入理解其驱动机制和控制荒漠化发展具有重要意义。以疏勒河流域为研究区,利用遥感和气象数据计算潜在NPP(PNPP)及其与实际NPP(ANPP)之间的差值,分别衡量了气候变化和人类活动对流域NPP的相对影响。研究结果表明:(1)2001—2015年疏勒河流域年ANPP整体呈缓慢增加趋势,与全国和西北地区相比,普遍较低,流域植被整体生产力水平不高。流域年ANPP空间分布呈现上游祁连山区和中下游绿洲区ANPP较高,而中下游荒漠戈壁区ANPP较低的分布格局。(2)2001—2015年流域年PNPP的变化趋势表明,降水量的变化是导致疏勒河流域植被退化加剧或缓解的主要气候驱动因素,但气温的变化对植被的影响较为复杂。(3)2001—2015年流域大部分地区植被退化系人类活动造成的,但人类活动的负向影响力在减弱。(4)气候变化和人类活动对植被NPP的相对影响均表现出明显的空间异质性,其中人类活动是疏勒河流域植被变化的主要驱动因素。  相似文献   
109.
雨生红球藻中虾青素的研究与应用   总被引:1,自引:0,他引:1  
雨生红球藻是单细胞微藻,其中的虾青素具有抗氧化、抗肿瘤、预防心脑血管疾病等多种生物活性,在食品、医药、保健品、化妆品及养殖业有诸多用途。概述了雨生红球藻虾青素含量影响因素,雨生红球藻培养方法、虾青素的提取方法及其应用领域等最新研究成果,为虾青素的开发利用提供帮助。  相似文献   
110.
Fourteen phenolic derivatives including two new compounds (1, 2), one new natural product (10) and eleven known ones (3 - 9 and 11–14) were obtained from the roots of Fallopia multiflora var. ciliinervis. The structures were determined using IR, MS, 1D and 2D NMR spectroscopy and the absolute configuration of the new structure (2) was deduced by ECD experiments. All of the isolated compounds were assayed for their cytotoxic activities against three tumor cell lines (A549, HCT116 and SW620) and the results showed that compounds 12-14 showed cytotoxicities against A549 cells while compounds 10 and 11 showed cytotoxicities against SW620 cells.  相似文献   
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