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101.
Naveen Kumar Arora Ekta Khare Ji Hoon Oh Sun Chul Kang Dinesh K. Maheshwari 《World journal of microbiology & biotechnology》2008,24(4):581-585
Rhizoctonia solani and Phytophthora capsici are two of the most destructive phytopathogens occurring worldwide and are only partly being managed by traditional control
strategies. Fluorescent Pseudomonas isolates PGC1 and PGC2 were checked for the antifungal potential against R. solani and P. capsici. Both the isolates were screened for the ability to produce a range of antifungal compounds. The results of this study indicated
the role of chitinase and β-1,3-glucanase in the inhibition of R. solani, however, antifungal metabolites of a non-enzymatic nature were responsible for inhibition of P. capsici. The study confirmed that multiple and diverse mechanisms are adopted by the same antagonist to suppress different phytopathogens,
as evidenced in case of R. solani and P. capsici. 相似文献
102.
Dinesh S. Bhoj Mohammad Ahsanullah 《Biometrical journal. Biometrische Zeitschrift》1993,35(3):355-359
The test statistics are proposed for testing the equality of the coefficients of variation of two normal populations based on independent samples. The asymptotic distributions of the statistics are approximated by well-known distributions. The empirical sizes and powers of these statistics are computed and compared. 相似文献
103.
104.
Qingqing Zhou Tristan A. Reekie Ramzi H. Abbassi Dinesh Indurthi Venkata Josep S. Font Renae M. Ryan Lenka Munoz Michael Kassiou 《Bioorganic & medicinal chemistry》2018,26(22):5852-5869
Dual-specificity tyrosine phosphorylation-related kinase 1A (DYRK1A) is a dual-specificity protein kinase that catalyses phosphorylation and autophosphorylation. Higher DYRK1A expression correlates with cancer, in particular glioblastoma present within the brain. We report here the synthesis and biological evaluation of new heterocyclic diphenolic derivatives designed as novel DYRK1A inhibitors. The generation of these heterocycles such as benzimidazole, imidazole, naphthyridine, pyrazole-pyridines, bipyridine, and triazolopyrazines was made based on the structural modification of the lead DANDY and tested for their ability to inhibit DYRK1A. None of these derivatives showed significant DYRK1A inhibition but provide valuable knowledge around the importance of the 7-azaindole moiety. These data will be of use for developing further structure-activity relationship studies to improve the selective inhibition of DYRK1A. 相似文献
105.
Alfonso Aceves‐Aparicio Horacio Tapia‐McClung Rogelio Macías‐Ordóñez Dinesh Rao 《Ethology : formerly Zeitschrift fur Tierpsychologie》2018,124(7):458-467
Less than 0.2% of all spider species live in close associations with conspecifics. Among these, subsocial spiders show characteristics of both solitary spiders (e.g., individuals disperse for breeding) and social spiders (e.g., prolonged cooperative behaviours at least prior to independent reproduction). Dispersing individuals build small webs, usually with one inhabitant, whereas colonies are large webs with plant debris and harbouring multiple females. We studied the spatiotemporal dynamics of dispersal in the subsocial spider Anelosimus baeza. We followed the occupancy of all colonies and dispersal webs over the breeding season by mapping the number and sex of spiders with respect to their location in three dimensions. We studied the settlement patterns of new webs and fluctuation in web occupancy through movement between occupied and abandoned webs of colonies and dispersal webs. The occupancy of webs was highly dynamic with changes occurring at small time scales. The similarity in the patterns of web occupancy by females among dispersal webs was partially explained by their spatial and their temporal proximity. Our results suggest that dispersal webs may be used by spiders as a temporary refuge by both sexes during the breeding season. Patterns described here suggest new approaches to dispersal studies in group living spiders. 相似文献
106.
Enhanced reproductive success revealed key strategy for persistence of devastated populations in Himalayan food‐deceptive orchid,Dactylorhiza hatagirea 下载免费PDF全文
Anthropogenic disturbances adversely affect populations of rare and endemic plants, resulting in reduction of their population size and performance. Among different plant groups, deceptive terrestrial orchids are vulnerable and possess greater extinction risks because of rarity in occurrence. To understand the response of food‐deceptive terrestrial orchids to disturbances, we selected Dactylorhiza hatagirea as our representative species, which is endemic to Himalaya, and studied its natural populations. This species is rare for being habitat specific, pollination limited and threatened in its natural habitats. We tested the hypothesis that disturbances lead to reduction in population size and plant performance of food‐deceptive terrestrial orchids. For assessing the impact of disturbance, two contrasting groups, heavily devastated (HD) and lightly devastated (LD), were identified on the basis of frequency and intensity of disturbance (harvesting of plant for tubers) by interviewing local people, medicinal plant extractors and shepherds. HD sites, in comparison to LD sites, were found to have smaller population sizes, but showed an increase in plant growth traits (plant height, specific leaf area, leaf N and specific shoot length). Similarly, plants at HD sites were found to have invested less in inflorescence (inflorescence size, inflorescence length, inflorescence length fraction and flowers per length), but despite that showed higher reproductive success. This was a clear indication of enhanced performance of its populations driven by disturbances. Our findings suggested that food‐deceptive species in small populations tend to reduce the probability of population extinction and have the capability to recover rapidly if conserved in time. 相似文献
107.
Meenakshi Sharma Dinesh Kumar Krishna Mohan Poluri 《Biochimica et Biophysica Acta (BBA)/General Subjects》2018,1862(4):924-935
Background
Characterization of partially collapsed protein conformations at atomic level is a daunting task due to their inherent flexibility and conformational heterogeneity. T7 bacteriophage endolysin (T7L) is a single-domain amidase that facilitates the lysis of Gram-negative bacteria. T7L exhibits a pH-dependent structural transition from native state to partially folded (PF) conformation. In the pH range 5–3, T7L PF states display differential ANS binding characteristics.Methods
CD, fluorescence, NMR spectroscopy and lysis assays were used to investigate the structure-stability- dynamics relationships of T7L PF conformations.Results
Structural studies indicated a partial loss of secondary/tertiary structures compared to its native state. The loss in the tertiary structure and the hydrophobic core opening increases upon decrease of pH from 5 to 3. Thermal denaturation experiments delineated that the pH?5 conformation is thermally irreversible in contrast to pH?3, depicting that hydrophobic core opening is essential for thermal reversibility. Further, urea dependent unfolding features of PF state at pH?5 and 4 evidenced for a collapsed conformation at intermediate urea concentrations. Residue level studies revealed that α1-helix and β3-β4 segment of T7L are the major contributors for such a structural collapse and inherent dynamics.Conclusions
The results suggested that the low pH PF states of T7L are heterogeneous and exhibits differential structural, unfolding, thermal reversibility, and dynamic features.General significance
Unraveling the structure-stability characteristics of different endolysin conformations is essential for designing novel chimeric and engineered phage endolysins as broadband antimicrobial agents over a varied pH range. 相似文献108.
109.
This paper investigates the effect of temperature on the elastic modulus of carbon nanotube-polyethylene (CNT-PE) nanocomposite and its interface using molecular dynamics (MD) simulations, by utilizing the second-generation polymer consistent force field (PCFF). Two CNTs—armchair and zigzag—were selected as reinforcing nano-fillers, and amorphous PE was used as the polymer matrix. For atomistic modelling of the nanocomposite, the commercially available code Materials Studio 8.0 was used and all other MD simulations were subsequently performed using the open source code Large-Scale Atomic/Molecular Massively Parallel Simulator (LAMMPS). To obtain the elastic modulus of the nanocomposite, stress-strain curves were drawn at different temperatures by performing uniaxial deformation tests on the nanocomposite material, whereas the curvatures of the interfacial interaction energy vs. strain curves were utilized to obtain Young’s modulus of the interface. In addition, the glass transition temperatures of the polymer matrix and nanocomposites were also evaluated using density-temperature curves. Based on the results, it is concluded that, irrespective of temperature condition, a nanocomposite reinforced with CNT of larger chirality (i.e., armchair) yields a higher value of Young’s modulus of the nanocomposite and its interface. It was also found that, at the phase transition (from a glassy to a rubbery state) temperature (i.e., glass transition temperature), Young’s moduli of the polymer matrix, nanocomposite, and its interface drop suddenly. The results obtained from MD simulations were verified with results obtained from continuum-based rule-of-mixtures. 相似文献
110.