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61.
The metabolic reasons associated with differential sensitivity of C3 and C4 plant species to enhanced UV-B under varying soil nutrient levels are not well understood. In the present study, spinach (Spinacia oleracea L. var All Green), a C3 and amaranthus (Amaranthus tricolor L. var Pusa Badi Chaulai), a C4 plant were subjected to enhanced UV-B (280–315 nm; 7.2 kJ m?2 day?1) over ambient under varying soil nutrient levels. The nutrient amendments were recommended Nitrogen (N), Phosphorus (P), Potassium (K), 1.5× recommended NPK, 1.5× recommended N and 1.5× recommended K. Enhanced UV-B negatively affected both the species at all nutrient levels, but the reductions varied with nutrient concentration and combinations. Reductions in photosynthetic rate, stomatal conductance and chlorophyll content were significantly more in spinach compared with amaranthus. The reduction in photosynthetic rate was maximum at 1.5× recommended K and minimum in 1.5× NPK amended plants. The oxidative damage to membranes measured in terms of malondialdehyde content was significantly higher in spinach compared with amaranthus. Enhanced UV-B reduced SOD activity in both the plants except in amaranthus at 1.5× recommended K. POX activity increased under enhanced UV-B at all nutrient levels in amaranthus, but only at 1.5× K in spinach. Amaranthus had significantly higher UV-B-absorbing compounds than spinach even under UV-B stress. Lowest reductions in yield and total biomass under enhanced UV-B compared with ambient were observed in amaranthus grown at 1.5× recommended NPK. Enhanced UV-B did not significantly change the nitrogen use efficiency in amaranthus at all NPK levels, but reduced in spinach except at 1.5× K. These findings suggest that the differential sensitivity of the test species under enhanced UV-B at varying nutrient levels is due to varying antioxidative and UV-B screening capacity, and their ability to utilize nutrients. Amaranthus tolerated enhanced UV-B stress more than spinach at all nutrient levels and 1.5× recommended NPK lowered the sensitivity maximally to enhanced UV-B with respect to photosynthesis, biomass and yield. PCA score has also confirmed the lower sensitivity of amaranthus compared with spinach with respect to the measured physiological and biochemical parameters. 相似文献
62.
We evaluated the effects of brucine on N-nitrosodiethylamine (DENA)-induced hepatocarcinogenesis in rats. Initiation of hepatocarcinogenesis was done by intraperitoneal injection of diethylnitrosamine (DENA) followed by promotion with phenobarbital. The rats were exposed to dietary brucine for 4 weeks prior to initiation, and the treatment was continued for 22 consecutive weeks. Brucine decreased the incidence, total number, multiplicity, size and volume of preneoplastic hepatic nodules in a dose-dependent manner. Administration of DENA induced hepatocellular carcinoma (HCC), as evidenced by changes in histopathological architecture, increased activity of cytochrome P450, decreased activity of glutathione Stransferase (GST) as well as decreased antioxidant status, enhanced lipid peroxidation, increased liver marker enzymes. Western blot analysis showed decreased expression of cyclin D1 and Bcl-2 with activation of caspase-3 and increased expression of Bax. Immunohistochemical demonstrated the decreased expression of the PCNA and VEGF. These results indicate that brucine prevents lipid peroxidation and hepatic cell damage and also protects the antioxidant system in DENA-induced hepatocarcinogenesis. 相似文献
63.
Nathaniel P. Sharp Aneil F. Agrawal 《Evolution; international journal of organic evolution》2013,67(4):1189-1195
In populations with males and females, sexual selection may often represent a major component of overall selection. Sexual selection could act to eliminate deleterious alleles in concert with other forms of selection, thereby improving the fitness of sexual populations. Alternatively, the divergent reproductive strategies of the sexes could promote the maintenance of sexually antagonistic variation, causing sexual populations to be less fit. The net impact of sexual selection on fitness is not well understood, due in part to limited data on the sex‐specific effects of spontaneous mutations on total fitness. Using a set of mutation accumulation lines of Drosophila melanogaster, we found that mutations were deleterious in both sexes and had larger effects on fitness in males than in females. This pattern is expected to reduce the mutation load of sexual females and promote the maintenance of sexual reproduction. 相似文献
64.
Chandra Bhushan Mishra Dimpy Sharma Amresh Prakash Namrata Kumari Nitin Kumar Pratibha Mehta Luthra 《Bioorganic & medicinal chemistry》2013,21(19):6077-6083
Novel 2-thioxothiazole derivatives (6–19) as potential adenosine A2A receptor (A2AR) antagonists were synthesized. The strong interaction of the compounds (6–19) with A2AR in docking study was confirmed by high binding affinity with human A2AR expressed in HEK293T cells using radioligand-binding assay. The compound 19 demonstrated very high selectivity for A2AR as compared to standard A2AR antagonist SCH58261. Decrease in A2AR-coupled release of endogenous cAMP in treated HEK293T cells demonstrated in vitro A2AR antagonist potential of the compound 19. Attenuation in haloperidol-induced impairment (catalepsy) in Swiss albino male mice pre-treated with compound 19 is evocative to explore its prospective in therapy of PD. 相似文献
65.
Renu Deswal Ravi Gupta Vivek Dogra Raksha Singh Jasmeet Kaur Abat Abhijit Sarkar Yogesh Mishra Vandana Rai Yelam Sreenivasulu Ramesh Sundar Amalraj Manish Raorane Ram Prasad Chaudhary Ajay Kohli Ashok Prabhakar Giri Niranjan Chakraborty Sajad Majeed Zargar Vishwanath Prasad Agrawal Ganesh Kumar Agrawal Dominique Job Jenny Renaut Randeep Rakwal 《Physiology and Molecular Biology of Plants》2013,19(4):461-477
Plant proteomics has made tremendous contributions in understanding the complex processes of plant biology. Here, its current status in India and Nepal is discussed. Gel-based proteomics is predominantly utilized on crops and non-crops to analyze majorly abiotic (49 %) and biotic (18 %) stress, development (11 %) and post-translational modifications (7 %). Rice is the most explored system (36 %) with major focus on abiotic mainly dehydration (36 %) stress. In spite of expensive proteomics setup and scarcity of trained workforce, output in form of publications is encouraging. To boost plant proteomics in India and Nepal, researchers have discussed ground level issues among themselves and with the International Plant Proteomics Organization (INPPO) to act in priority on concerns like food security. Active collaboration may help in translating this knowledge to fruitful applications. 相似文献
66.
67.
The aggregation of biotherapeutics is a major hindrance to the development of successful drug candidates; however, the propensity to aggregate is often identified too late in the development phase to permit modification to the protein's sequence. Incorporating rational design for the stability of proteins in early discovery has numerous benefits. We engineered out aggregation-prone regions on the Fab domain of a therapeutic monoclonal antibody, bevacizumab, to rationally design a biobetter drug candidate. With the purpose of stabilizing bevacizumab with respect to aggregation, 2 strategies were undertaken: single point mutations of aggregation-prone residues and engineering a glycosylation site near aggregation-prone residues to mask these residues with a carbohydrate moiety. Both of these approaches lead to comparable decreases in aggregation, with an up to 4-fold reduction in monomer loss. These single mutations and the new glycosylation pattern of the Fab domain do not modify binding to the target. Biobetters with increased stability against aggregation can therefore be generated in a rational manner, by either removing or masking the aggregation-prone region or crowding out protein-protein interactions. 相似文献
68.
69.
Trivedi Jayati Singh Jasvinder Atray Neeraj Ray S. S. Agrawal Deepti 《Bioprocess and biosystems engineering》2019,42(12):2047-2054
Bioprocess and Biosystems Engineering - In the present study, the effect of irradiance on growth performance of Scenedesmus obliquus was investigated, and various non-linear growth models were... 相似文献
70.
Yamini Thakur Mamta Tripathi Bharati Verma Rubi Khilari Rainy Agrawal Likheshwari 《Nucleosides, nucleotides & nucleic acids》2019,38(7):481-508
The polyadenylic acid [poly(A)] tail of mRNA plays a noteworthy role in the initiation of the translation, maturation, and stability of mRNA. It also significantly contributes to the production of alternate proteins in eukaryotic cells. Hence, it has recently been recognized as a prospective drug target. Binding affinity of bis(N-p-tolylbenzohydroxamato)Cobalt(II), [N-p-TBHA-Co(II)] (1) and bis(N-p-naphthylbenzohydroxamato)Copper(II), [N-p-NBHA-Cu(II)] (2) complexes with poly(A) have been investigated by biophysical techniques namely, absorption spectroscopy, fluorescence spectroscopy, diffuse reflectance infrared Fourier transform spectroscopy, circular dichroism spectroscopy, viscometric measurements and through molecular docking studies. The intrinsic binding constants (Kb) of complexes were determined following the order of N-p-TBHA-Co(II)] > N-p-NBHA-Cu(II), along with hyperchromism and a bathochromic shift for both complexes. The fluorescence quenching method revealed an interaction between poly(A)-N-p-TBHA-Co(II)/poly(A)-N-p-NBHA-Cu(II). The mode of binding was also determined via the fluorescence ferrocyanide quenching method. The increase in the viscosity of poly(A) that occurred from increasing the concentration of the N-p-TBHA-Co(II)/N-p-NBHA-Cu(II) complex was scrutinized. The characteristics of the interaction site of poly(A) with N-p-TBHA-Co(II)/N-p-NBHA-Cu(II) were adenine and phosphate groups, as revealed by DRS-FTIR spectroscopy. Based on these observations, a partial intercalative mode of the binding of poly(A) has been proposed for both complexes. Circular dichroism confirmed the interaction of both the complexes with poly(A). The molecular docking results illustrated that complexes strongly interact with poly(A) via the relative binding energies of the docked structure as ?259.39eV and ?226.30eV for N-p-TBHA-Co(II) and N-p-NBHA-Cu(II) respectively. Moreover, the binding affinity of N-p-TBHA-Co(II) is higher in all aspects than N-p-NBHA-Cu(II) for poly(A). 相似文献