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961.
T Bhaskar Kumar Ch Sumanth S Vaishaly M Srinivasa Rao KB Chandra Sekhar CL Meda A Kandale D Rambabu G Rama Krishna C Malla Reddy K Shiva Kumar KV Parsa M Pal 《Bioorganic & medicinal chemistry letters》2012,22(17):5639-5647
Novel polysubstituted pyrroles have been designed and accessed via a one-pot multicomponent reaction followed by Pd-mediated C-C bond forming reactions. All the compounds synthesized were tested for their PDE4B inhibitory properties in vitro and two of them obtained via Heck reaction showed significant inhibition. The docking results suggested that these alkenyl derivatives containing ester moiety interact well with the PDE4B protein in silico where the ester carbonyl oxygen played a key role. The pyrrole framework presented here could be a new template for the identification of small molecule based novel inhibitors of PDE4. The single crystal X-ray data of a representative compound is presented. 相似文献
962.
RR Pandey A Srivastava R Malasoni A Naqvi A Jain JP Maikhuri S Paliwal G Gupta AK Dwivedi 《Bioorganic & medicinal chemistry letters》2012,22(17):5735-5738
A series of twenty two derivatives of 3-(1-alkyl/aminoalkyl-3-vinyl-piperidin-4-yl)-1-(quinolin-4-yl)-propan-1-one and their 2-methylene derivatives were synthesized from naturally abundant cinchonine (I). Tartarate salts of these compounds were prepared and evaluated for spermicidal activity. The most active compounds (24, 27, 34, 36, and 38) showing potent spermicidal activity were further evaluated against different strains of Trichomonas vaginalis, for antimicrobial activity, in HeLa cell lines for cytotoxicity and against Lactobacillus jensenii for eco-safety. The tartarate of 3-(1-pentyl-3-vinyl-piperidin-4-yl)-1-(quinolin-4-yl)-propan-1-one (27) was found to be more active than N-9 in spermicidal activity. 相似文献
963.
M Ravinder B Mahendar S Mattapally KV Hamsini TN Reddy C Rohit K Srinivas SK Banerjee VJ Rao 《Bioorganic & medicinal chemistry letters》2012,22(18):6010-6015
Twenty-six 2-pyridone derivatives (8a-8z), which are structurally analogous to amrinone and milrinone two important cardiotonic drugs, are synthesized and characterized. The synthesis of 2-pyridone derivatives involves addition, followed by cyclization between Baylis-Hillman acetates (7a-7k) and enamino esters or nitriles (3a-3e). Thus synthesized pyridones were subjected to PDE3 inhibitory activity, 14 pyridones were found to be hits out of 26 pyridones synthesized and out of 14 hits, there are 5 pyridones found to be lead compounds having excellent PDE3 inhibitory activity. Further we have carried out computational analysis to understand protein/enzyme and 2-pyridone derivative interactions to identify amino acid residues involved in the vicinity of binding and compared with milrinone drug. 相似文献
964.
Shingnapurkar D Dandawate P Anson CE Powell AK Afrasiabi Z Sinn E Pandit S Venkateswara Swamy K Franzblau S Padhye S 《Bioorganic & medicinal chemistry letters》2012,22(9):3172-3176
Currently used anti-tubercular drugs target actively growing Mycobacterium tuberculosis (Mtb) but there are no current therapies targeting persistent mycobacteria. Isocitrate lyase (ICL) is an important enzyme of the glyoxylate shunt pathway used by Mtb for sustaining intracellular infection in inflammatory macrophages under conditions of stress such as nutrient depletion and anaerobic metabolism. Since the humans do not possess this enzyme it constitutes an attractive target for selective drug design. Present work describes synthesis and structural characterization of pyruvate-isoniazid conjugates and their copper complexes with potent anti-tubercular activities against M. tuberculosis H37Rv. 相似文献
965.
Venkat Ragavan R Vijayakumar V Rajesh K Palakshi Reddy B Karthikeyan S Suchetha Kumari N 《Bioorganic & medicinal chemistry letters》2012,22(12):4193-4197
A series of β-keto esters were synthesized from heteroaryl esters and ethyl acetate using LiHMDS as base at -50 to -30 °C. The increase in yields of cross condensed product were observed and the percentage of self condensed product was reduced drastically by applying the suitable base (LiHMDS), solvent and the minimum amount of ethyl acetate. All these β-keto esters were characterized using (1)H NMR, (13)C NMR and mass spectral data. A plausible mechanism is also depicted to prove the formation of trans-esterified products. All the synthesized compounds were subjected to test for their cytotoxicity towards various cancer cell lines and also tested for their antimicrobial activity towards various bacterial and fungal strains and some of them were found to have promising activity. 相似文献
966.
Chaturvedula PV Pin S Tholady G Conway CM Macor JE Dubowchik GM 《Bioorganic & medicinal chemistry letters》2012,22(14):4719-4722
We report the synthesis of rigid spirocyclic systems as conformationally constrained variants of the Ala-Phe-NH(2) dipeptide amide C-terminus of the calcitonin gene-related peptide (CGRP). CGRP receptor antagonists containing these moieties displayed potent affinity, functional antagonism and excellent oxidative stability. Structure-activity relationship studies demonstrated the relative importance of hydrogen bond donor/acceptor functionalities and the preferred orientation of an aromatic ring. Antagonists showed potent and full reversal of CGRP-induced dilation of ex vivo human intracranial arteries. 相似文献
967.
Mandadapu SR Weerawarna PM Gunnam MR Alliston KR Lushington GH Kim Y Chang KO Groutas WC 《Bioorganic & medicinal chemistry letters》2012,22(14):4820-4826
A series of structurally-diverse α-ketoamides and α-ketoheterocycles was synthesized and subsequently investigated for inhibitory activity against norovirus 3CL protease in vitro, as well as anti-norovirus activity in a cell-based replicon system. The synthesized compounds were found to inhibit norovirus 3CL protease in vitro and to also exhibit potent anti-norovirus activity in a cell-based replicon system. 相似文献
968.
Kamal A Srikanth YV Ramaiah MJ Khan MN Kashi Reddy M Ashraf M Lavanya A Pushpavalli SN Pal-Bhadra M 《Bioorganic & medicinal chemistry letters》2012,22(1):571-578
A series of bisindole-pyrrolobenzodiazepine conjugates (5a-f) linked through different alkane spacers was prepared and evaluated for their anticancer activity. All compounds exhibited significant anticancer potency and the most potent compounds 5b and 5e were taken up for detailed studies on MCF-7 cell line. Cell cycle effects were examined apart from investigating the inhibition of tubulin polymerization for compounds 2a, 2b, 5b and 5e at 2μM. FACS analysis showed that at higher concentrations (4 and 8μM) there was an increase of sub-G1 phase cells and decrease of G2/M phase cells, thus indicating that compounds 5b and 5e are effective in causing apoptosis in MCF-7 cells. It was also observed that compounds 5b and 5e showed the down regulation of histone deacetylase protein levels such as HDAC1, 2, 3, 8 and increase in the levels of p21, followed by apoptotic cell death. The apoptotic nature of these compounds was further evidenced by increased expression of cleaved-PARP and active caspase-7 in MCF-7 cells. 相似文献
969.
Purushotham Reddy S Chinnababu B Shekhar V Kumar Reddy D Bhanuprakash GV Velatoor LR Venkateswara Rao J Venkateswarlu Y 《Bioorganic & medicinal chemistry letters》2012,22(12):4182-4184
A simple, highly efficient and stereoselective synthetic route has been developed for synthesis of alpinoid-C (1) and its analogues (2, 3 and 4) from commercially available starting materials by using Wittig olefination, Sharpless asymmetric epoxidation, Grubbs cross metathesis as key steps. All the compounds showed moderate anti-proliferative activity against human leukemia/carcinoma (U-937, THP-1, COLO-205 and HepG2) and mouse melanoma (B16-F10) cancer cell lines. Compounds 3 and 4 are found to be most potent with an IC(50) of 7.53 μM and 32.26 μM on THP-1, 11.12 μM and 7.21 μM on COLO-205 cell lines, respectively. 相似文献
970.
Semi-synthesis and bio-evaluation of polybrominated diphenyl ethers from the sponge Dysidea herbacea
Srikanth Reddy T Suryakiran N Narasimhulu M Ramesh D Chinni Mahesh K Sai Krishna A Kavitha P Venkateswara Rao J Venkateswarlu Y 《Bioorganic & medicinal chemistry letters》2012,22(14):4900-4906
The sponge Dysidea herbacea was collected from the Mandapam Coast, Tamilnadu, India. Isolated gram quantities of hydroxylated polybrominated diphenyl ether (HO-PBDE) and semi-synthesized a series of new PBDEs derivatives and tested them for antibacterial and cytotoxic activities. 相似文献