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71.
72.
Synthesis and biological evaluation of potential modulators of malarial glutathione-S-transferase(s)
Rumana Ahmad Arvind K. Srivastava Rama Pati Tripathi Sanjay Batra Rolf D. Walter 《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):327-342
Glutathione-S-transferase(s) (E.C.2.5.1.18, GSTs) have been investigated in parasitic protozoans with respect to their biochemistry and they have been identified as potential vaccine candidates in protozoan parasites and as a target in the synthesis of new antiparasitic agents. In a search towards the identification of novel biochemical targets for antimalarial drug design, the area of Plasmodium glutathione metabolism provides a number of promising chemotherapeutic targets. GST activity was determined in various subcellular fractions of malarial parasites Plasmodium yoelii and was found to be localized mainly in the cytosolic fraction (specific activity, c. 0.058 ± 0.016 μmol/min/mg protein). Hemin, a known inhibitor of mammalian GST(s), maximally inhibited this enzyme from P. yoelii to nearly 86%. In a search towards synthetic modulators of malarial GST(s), 575 compounds belonging to various chemical classes were screened for their effect on crude GST from P. yoelii and 92 compounds belonging to various chemical classes were studied on recombinant GST from P. falciparum. Among all the compounds screened, 83 compounds inhibited/stimulated the enzyme from P. yoelii/P. falciparum to the extent of 40% or more. 相似文献
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74.
Abid Ali Divya Gupta Gaurava Srivastava Ashok sharma 《Journal of biomolecular structure & dynamics》2019,37(8):2061-2071
The discovery of NDM-1 and its variants has caused the emergence of antibiotic resistance in the community and hospital setting, causing major concern for health care across the globe. New Delhi Metallo-β-lactamase is known to hydrolyse almost all β-lactam antibiotics. Studies have shown the hydrolytic activates of NDM-1 and some of its variants, however a comparative study of these NDM variants has not been explored in detail. Hence, we proposed to check their catalytic activity by performing a comparative study between NDM-1 and its variants. The study was initiated to clone NDM variants (NDM-1, NDM-4, NDM-5, NDM-6 and NDM-7) followed by overexpression of the recombinant proteins to check their hydrolytic properties against β-lactam antibiotics. The minimum inhibitory concentration of carbapenems antibiotics for blaNDM-5 clone was found four fold increased, whereas no change was observed in the clones having other variants. The hydrolytic activity of carbapenem with NDM-5 variant was found to be augmented as per the kinetics parameter where Km was decreased and kcat, kcat/Km values increased as compared to the NDM-1. Molecular docking studies were employed to identify the variations in the binding ability among all NDM variants with imipenem or meropenem. Simulation studies at 100?ns showed a good stability of NDM-5 with imipenem and meropenem as compared to NDM-1. CD spectroscopy data revealed significant changes in the secondary structure of NDM variants. We conclude that NDM-5 showed higher hydrolytic activity as compared to other variants. This study provides a comparative analysis of the severity of NDM producing strains. 相似文献
75.
Satyajeet Das Sagar Batra Pramodkumar P. Gupta Mukesh Kumar Vijay Kumar Srivastava Anupam Jyoti Nagendra Singh Sanket Kaushik 《Journal of molecular recognition : JMR》2019,32(11)
Enterococcus faecalis is a gram‐positive, rod‐shape bacteria responsible for around 65% to 80% of all enterococcal nosocomial infections. It is multidrug resistant (MDR) bacterium resistant to most of the first‐line antibiotics. Due to the emergence of MDR strains, there is an urgent need to find novel targets to develop new antibacterial drugs against E. faecalis. In this regard, we have identified naphthoate synthase (1,4‐dihydroxy‐2‐naphthoyl‐CoA synthase, EC: 4.1.3.36; DHNS) as an anti‐E. faecalis target, as it is an essential enzyme for menaquinone (vitamin K2) synthetic pathway in the bacterium. Thus, inhibiting naphtholate synthase may consequently inhibit the bacteria's growth. In this regard, we report here cloning, expression, purification, and preliminary structural studies of naphthoate synthase along with in silico modeling, molecular dynamic simulation of the model and docking studies of naphthoate synthase with quercetin, a plant alkaloid. Biochemical studies have indicated quercetin, a plant flavonoid as the potential lead compound to inhibit catalytic activity of EfDHNS. Quercetin binding has also been validated by spectrofluorimetric studies in order to confirm the bindings of the ligand compound with EfDHNS at ultralow concentrations. Reported studies may provide a base for structure‐based drug development of antimicrobial compounds against E. faecalis. 相似文献
76.
Chandra Dinesh Srivastava Rashmi Gupta Vadakattu V. S. R. Franco Christopher M. M. Paasricha Nishat Saifi Shabnam K. Tuteja Narendra Sharma Anil Kumar 《Plant and Soil》2019,441(1-2):261-281
Plant and Soil - Plant growth promoting bacteria (PGPB) containing 1-aminocyclopropane-1-carboxylate (ACC) deaminase can play an important role in abiotic stress tolerance in plants, particularly... 相似文献
77.
Ravi K. Asthana Arunima Srivastava Akhilesh P. Singh Deepali Sureshwar P. Singh Gopal Nath Ranjana Srivastava Brahm S. Srivastava 《Journal of applied phycology》2006,18(1):33-39
The active principle in a methanolic extract of the laboratory-grown cyanobacterium, Fischerella sp. isolated from Neem (Azadirachta indica) tree bark was active against Mycobacterium tuberculosis, Enterobacter aerogenes, Staphylococcus aureus, Pseudomonas aeruginosa, Salmonella typhi, Escherichia coli as well as three multi-drug resistant E. coli strains in in vitro assays. Based on MS, UV, IR 1H NMR analyses the active principle is proposed to be hapalindole T having the empirical formula C21H23N2ClSO and a molecular weight of 386 with the melting point range 179–182 °C. The estimated production of Hapalindole T from the cyanobacterium is 1.25 mg g−1 lyophilized biomass. It is suggested that cyanobacteria colonizing specialized niches such as tree bark could be an antibacterial drug resource. 相似文献
78.
Darshani Priya Sen Sarma Shreya Srivastava Amit K. Baishya Rinku Kumar Deepak 《Phytochemistry Reviews》2022,21(6):1761-1842
Phytochemistry Reviews - Triterpenes are naturally occurring derivatives biosynthesized following the isoprene rule of Ruzicka. The triterpenes have been reported to possess a wide range of... 相似文献
79.
Yadav Shweta Gupta Ekta Patel Anju Srivastava Suchi Mishra Virendra Kumar Singh Poonam C. Srivastava Pankaj Kumar Barik Saroj Kanta 《Reviews in Environmental Science and Biotechnology》2022,21(3):771-798
Reviews in Environmental Science and Bio/Technology - In the past few decades, pollution from microplastics has emerged as an important issue on a global scale. These plastic particles are mainly... 相似文献
80.
Tiwari Anjani Kumar Adhikari Anupriya Mishra Lokesh Chandra Srivastava Abhishek 《Neurochemical research》2022,47(9):2499-2512
Neurochemical Research - Human/animal brain is a unique organ with substantially high metabolism but it contains no energy reserve that is the reason it requires continuous supply of O2 and energy... 相似文献