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161.
Electrochemistry of microperoxidase-11 (MPx-11) anchored on the mixed self-assembled monolayer (SAM) of 2-(2-mercaptoethylpyrazine) (PET) and 4,4'-dithiodibutyric acid (DTB) on gold (Au) electrode and the biosensing of uric acid (UA) is described. MPx-11 has been covalently anchored on the mixed SAM of PET and DTB on Au electrode. MPx-11 on the mixed self-assembly exhibits reversible redox response characteristic of a surface confined species. The heterocyclic ring of PET promotes the electron transfer between the electrode and the redox protein. The apparent standard rate constant kapps obtained for the redox reaction of MPx-11 on the mixed monolayer is approximately 2.15 times higher than that on the single monolayer of DTB modified electrode. MPx-11 efficiently mediates the electrocatalytic reduction of H2O2. MPx-11 electrode is highly sensitive to H2O2 and it shows linear response for a wide concentration range. The electrocatalytic activity of the MPx-11 electrode is combined with the enzymatic activity of uricase (UOx) to fabricate uric acid biosensor. The bienzyme assembly is highly sensitive towards UA and it could detect UA as low as 2 microM at the potential of -0.1 V. The biosensor shows linear response with a sensitivity of 3.4+/-0.08 nA cm(-2) microM(-1). Ascorbate (AA) and paracetamol (PA) do not significantly interfere in the amperometric sensing of UA. 相似文献
162.
Ira Vashisht Prashant Mishra Tarun Pal Sreekrishna Chanumolu Tiratha Raj Singh Rajinder Singh Chauhan 《Planta》2015,241(5):1269-1270
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Population status and habitat occupancy of endangered river dolphins in the Karnali River system of Nepal during low water season
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Shambhu Paudel Yajna Prasad Timilsina Jennifer Lewis Tom Ingersoll Shant Raj Jnawali 《Marine Mammal Science》2015,31(2):707-719
Ganges river dolphin abundance has undergone a predominant decline across its range since monitoring began. In Nepal, disappearance from some of the rivers it once used has already occurred. Today this species can only be found in three river systems in Nepal, the Karnali, Sapta Koshi, and Narayani, but numbers are low in these locations. To determine the abundance of dolphins remaining in the Karnali system (which includes the Karnali, Geruwa, and Mohana), and factors affecting dolphin habitat use, we conducted surveys where we recorded dolphin presence. Dolphins within this river system were sighted only in the Karnali and an abundance estimate of 5.04 ± 0.753 SE was calculated. This pattern of ranging differed from that previously reported (from previous sightings only in the Geruwa to current sightings only in the Karnali). River depth likely contributed to the presence or absence of dolphins. Shifts in available habitat between the Geruwa and Karnali have resulted from changes in the course of the main stream Karnali following construction of the Chisapani irrigation intake. Because of the low numbers of dolphins reported, there is great concern that loss of this species in Nepal is likely in the near future. 相似文献
167.
Analysis of Pathogenic Diversity of the Rice Bacterial Blight Pathogen (Xanthomonas oryzae pv. oryzae) in the Andaman Islands and Identification of Effective Resistance Genes
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Raj K. Gautam Pankaj K. Singh Krishnan Sakthivel Muthulingam Srikumar Naresh Kumar Krishna Kumar Awnindra K. Singh Sibnarayan Dam Roy 《Journal of Phytopathology》2015,163(6):423-432
Bacterial blight (BB) caused by Xanthomonas oryzae pv. oryzae (Xoo) is a major disease of rice in the tropics for which genetic resistance in the host plants is the only effective solution. This study aimed at identification of resistance gene combinations effective against Xoo isolates and fingerprinting of the Xoo isolates of Andaman Islands (India). Here, we report the reaction of 21 rice BB differentials possessing Xa1 to Xa21 genes individually and in different combinations to various isolates of pathogen collected from Andaman Islands. Pathological screening results of 14 isolates revealed that among individual genes tested across 2 years, Xa4, Xa7 and Xa21 conferred resistance reaction across all isolates, whereas among combinations, IRBB 50 (Xa4 + xa5), IRBB 52 (Xa4 + Xa21) and IRBB 60 (Xa4 + xa5 + xa13 + Xa21) conveyed effective resistance against tested isolates. The nature of genetic diversity among four isolates selected on the basis of geographical isolation in the islands was studied through DNA finger printing. The RAPD primers S111, S119, S1117, S1109, S1103, S109 and S105 were found to be better indicators of molecular diversity among isolates than JEL primers. The diversity analysis grouped 14 isolates into three major clusters based on disease reaction wherein isolate no. 8 was found the most divergent as well as highly virulent. The remaining isolates were classified into two distinct groups. The importance of the study in the context of transfer of resistance gene(s) in the local cultivars specifically for tropical island conditions is presented and discussed. 相似文献
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Holger Maier Christine Schütt Ralph Steinkamp Anja Hurt Elida Schneltzer Philipp Gormanns Christoph Lengger Mark Griffiths David Melvin Neha Agrawal Rafael Alcantara Arthur Evans David Gannon Simon Holroyd Christian Kipp Navis Pretheeba Raj David Richardson Sophie LeBlanc Laurent Vasseur Hiroshi Masuya Kimio Kobayashi Tomohiro Suzuki Nobuhiko Tanaka Shigeharu Wakana Alison Walling David Clary Juan Gallegos Helmut Fuchs Martin Hrabě de Angelis Valerie Gailus-Durner 《Mammalian genome》2015,26(9-10):467-481
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Jae Hoon Sul Towfique Raj Simone de Jong Paul I.W. de Bakker Soumya Raychaudhuri Roel A. Ophoff Barbara E. Stranger Eleazar Eskin Buhm Han 《American journal of human genetics》2015,96(6):857-868
In studies of expression quantitative trait loci (eQTLs), it is of increasing interest to identify eGenes, the genes whose expression levels are associated with variation at a particular genetic variant. Detecting eGenes is important for follow-up analyses and prioritization because genes are the main entities in biological processes. To detect eGenes, one typically focuses on the genetic variant with the minimum p value among all variants in cis with a gene and corrects for multiple testing to obtain a gene-level p value. For performing multiple-testing correction, a permutation test is widely used. Because of growing sample sizes of eQTL studies, however, the permutation test has become a computational bottleneck in eQTL studies. In this paper, we propose an efficient approach for correcting for multiple testing and assess eGene p values by utilizing a multivariate normal distribution. Our approach properly takes into account the linkage-disequilibrium structure among variants, and its time complexity is independent of sample size. By applying our small-sample correction techniques, our method achieves high accuracy in both small and large studies. We have shown that our method consistently produces extremely accurate p values (accuracy > 98%) for three human eQTL datasets with different sample sizes and SNP densities: the Genotype-Tissue Expression pilot dataset, the multi-region brain dataset, and the HapMap 3 dataset. 相似文献
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