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971.
Due to the unpredictable climate change, drought stress is being considered as one of the major threats to crop production. Wheat (Triticum aestivum L. cv. BARI Gom-26) being a dry season crop frequently faces scarcity of water and results in a lower yield. Therefore, this experiment aims to explore the role of different organic amendments (OAs) in mitigating drought stress-induced damage. The pot experiment consisted of different organic amendments viz. compost, vermicompost and poultry manure @0.09 kg m−2 soil, biochar @2.5% w/w soil and chitosan @1% w/w soil which was imposed on the plants grown under both well-watered and drought conditions. Results showed that drought stress reduced plant height (15%), SPAD value (16%), relative water content (13%), number of spikelet spike−1 (17%), number of grains spike−1 (12%), and 100-grain weight (18%). Organic amendments act as a protectant and reduce drought stress-induced damages by enhancing the morpho-physiological and yield attributes. Vermicompost enhanced SPAD value by 18%, number of spikelets spike−1 by 20%, number of grains spike−1 by 17%, whereas poultry manure increased plant height by 16% under drought condition compared to control plant. Unlike other OAs applied, vermicompost was proved to be capable of reducing the higher lipid peroxidation and proline content raised by drought condition. Drought stress-induced increment of catalase, ascorbate peroxidase and glutathione reductase activities were also efficiently modulated by the organic amendment application. The present study concluded that OAs play significant roles in alleviating drought stressinduced damages by improving the morpho-physiological attributes and among the different types of OAs used vermicompost performed better which in addition ceased the production of reactive oxygen species.  相似文献   
972.
Tomato is an important field crop, and nutritional imbalances frequently reduce its yield. Diagnosis and Recommendation Integrated System (DRIS), uses ratios for nutrient deficiency diagnosis instead of absolute concentration in plant tests. In this study, local DRIS norms for the field tomatoes were established and the nutrient(s) limiting tomatoes yield were determined. Tomato leaves were analyzed for nutrients, to identify nutritional status using the DRIS approach. One hundred tomatoes fields were selected from Chatter Plain Khyber Pakhtunkhwa and the Sheikupura Punjab Pakistan. The first fully matured leaf was sampled, rinsed, dried and ground for analyzing P, K, Ca, Mg, Cu, Fe, Mn and Zn using an Inductively Coupled Plasma Atomic Emission Spectrophotometer (ICP AES). Plant tissue N and S were measured by the combustion method. The tomatoes yields were recorded at each location. The data were divided into high-yielding (≥3.79 kg/10 plant) and low-yielding (<3.79 kg/10 plant) populations and norms were computed using standard DRIS procedures. High-yielding plant population had a statistically greater mean S and Fe than the low-yielding population. The average balance index, the sum of functions, for S and Fe were −11.04 and −5.17 which reflected deficiency of S and Fe. Plant nutrients norms established may optimize plant nutrition in field tomatoes for high yield.  相似文献   
973.
Awan  Sliha  Hashmi  Aisha N.  Taj  Rizwan  Munir  Sadaf  Habib  Rabia  Batool  Sajida  Azam  Maleeha  Qamar  Raheel  Nurulain  Syed M. 《Biochemical genetics》2022,60(2):720-737
Biochemical Genetics - Major depressive disorder (MDD) is characterized as clinical depression, which primarily affects the mood and behaviour of an individual. In the present study...  相似文献   
974.
BioMetals - In this communication, we feature the synthesis and in-depth characterization of a series of silver(I) complexes obtained from the complexation of quinolin-4-yl Schiff base ligands...  相似文献   
975.

Background

Cryoballoon-based pulmonary vein isolation (PVI) is a treatment option for atrial fibrillation (AF). Left atrial volume (LAV) and left atrial volume index (LAVi) are important parameters for long term success of PVI. Galectin-3 (Gal-3) and neutrophil to lymphocyte ratio (N/L ratio) are biomarkers to demonstrate the cardiac fibrosis and remodelling.

Methods

50 patients with symptomatic PAF despite ≥1 antiarrhythmic drug(s), who underwent PVI were enrolled. LAV, LAVi, Gal-3 and N/L ratio were calculated before ablation and after ablation at 6 and 12 months. According to AF recurrence patients were divided into two groups, recurrent AF (n?=?14) and non-recurrent AF (n?=?36).

Results

In both groups (recurrent and non-recurrent), initial and 12 months follow-up LAV values were 41.39?±?18.13?ml and 53.24?±?22.11?ml vs 48.85?±?12.89?ml and 42.08?±?13.85 (p?=?0.037). LAVi were 20.9?±?8.91 ml/m2 and 26.85?±?11.28 ml/m2 vs 25.36?±?6.21 and 21.87?±?6.66 (p?=?0.05) for recurrent and non-recurrent AF groups, respectively. In both groups PVI had no significant effect on serum Gal-3 levels and N/L ratio during 12 months follow-up. The comparison between two groups at the end of 12th month showed Gal-3 values of 6.66?±?4.09?ng/ml and 6.02?±?2.95?ng/ml (p?=?0.516), N/L ratio values of 2.28?±?1.07 103/μl and 1.98?±?0.66?103/μl (p?=?0.674).

Conclusion

LAV and LAVi are useful to predict the remodelling of the left atrium and AF recurrence after cryoballoon-based PVI. However, biomarkers such as Gal-3 and N/L ratio are not associated with AF recurrence.  相似文献   
976.
977.
Abstract

High content of chromium in plants hampers plants’ metabolism, disrupts plant growth and development. Therefore, improving plants’ tolerance to Cr toxicity is very essential. In our present study, we investigated the role of citric acid (CA) on chromium detoxification in terms of stress tolerance in rice. Application of CA under Cr stress restore the growth parameters, total protein content and membrane stability confirming that CA plays important role in Cr detoxification in rice. However, supplementation of CA under Cr stress caused no significant change in root Cr content but increased shoot Cr concentration (97?µg/g) compare with Cr stressed plant (24?µg/gm), suggesting that CA alleviates Cr toxicity by its chelating properties. Moreover, Fe content showed no significant changes due to CA supplementation under Cr stress, implying that Fe regulation is not involved with CA-mediated mitigation of Cr toxicity in rice. Furthermore, increased CAT, POD, and GR activity along with raised metabolites (glutathione and proline) indicates active participation in ROS scavenging and palliate the Cr toxicity in rice.  相似文献   
978.
Enzyme‐coated polymeric membranes are versatile catalysts for biofuel production and other chemical production from feedstock, like plant biomass. Such bioreactors are more energy efficient than high temperature methods because enzymes catalyze chemical reactions near room temperature. A major challenge in processing plant biomass is the presence of lignin, a complex aromatic polymer that resists chemical breakdown. Therefore, membranes coated with enzymes such as laccase that can degrade lignin are sought for energy extraction systems. We present an experimental study on optimizing an enzyme‐based membrane bioreactor and investigate the tradeoff between high flow rate and short dwell time in the active region. In this work, zero flow rate voltammetry experiments confirm the electrochemical activity of Trametes versicolor laccase on conductive polymer electrodes, and a flow‐through spectroscopy device with laccase‐coated porous nylon membranes is used with a colorimetric laccase activity indicator to measure the catalysis rate and percent conversion as a function of reactant flow rate. Membrane porosity before and after laccase coating is verified with electron microscopy.  相似文献   
979.
The development of biodegradation treatment processes for oil sands process-affected water (OSPW) has been progressing in recent years with the promising potential of biofilm reactors. Previously, the granular activated carbon (GAC) biofilm process was successfully employed for treatment of a large variety of recalcitrant organic compounds in domestic and industrial wastewaters. In this study, GAC biofilm microbial development and degradation efficiency were investigated for OSPW treatment by monitoring the biofilm growth on the GAC surface in raw and ozonated OSPW in batch bioreactors. The GAC biofilm community was characterized using a next-generation 16S rRNA gene pyrosequencing technique that revealed that the phylum Proteobacteria was dominant in both OSPW and biofilms, with further in-depth analysis showing higher abundances of Alpha- and Gammaproteobacteria sequences. Interestingly, many known polyaromatic hydrocarbon degraders, namely, Burkholderiales, Pseudomonadales, Bdellovibrionales, and Sphingomonadales, were observed in the GAC biofilm. Ozonation decreased the microbial diversity in planktonic OSPW but increased the microbial diversity in the GAC biofilms. Quantitative real-time PCR revealed similar bacterial gene copy numbers (>109 gene copies/g of GAC) for both raw and ozonated OSPW GAC biofilms. The observed rates of removal of naphthenic acids (NAs) over the 2-day experiments for the GAC biofilm treatments of raw and ozonated OSPW were 31% and 66%, respectively. Overall, a relatively low ozone dose (30 mg of O3/liter utilized) combined with GAC biofilm treatment significantly increased NA removal rates. The treatment of OSPW in bioreactors using GAC biofilms is a promising technology for the reduction of recalcitrant OSPW organic compounds.  相似文献   
980.
Recently various pathways of human telomere (ht) DNA folding into G-quadruplexes and of ligand binding to these structures have been proposed. However, the key issue as to the nature of forces driving the folding and recognition processes remains unanswered. In this study, structural changes of 22-mer ht-DNA fragment (Tel22), induced by binding of ions (K+, Na+) and specific bisquinolinium ligands, were monitored by calorimetric and spectroscopic methods and by gel electrophoresis. Using the global model analysis of a wide variety of experimental data, we were able to characterize the thermodynamic forces that govern the formation of stable Tel22 G-quadruplexes, folding intermediates, and ligand-quadruplex complexes, and then predict Tel22 behavior in aqueous solutions as a function of temperature, salt concentration, and ligand concentration. On the basis of the above, we believe that our work sets the framework for better understanding the heterogeneity of ht-DNA folding and binding pathways, and its structural polymorphism.  相似文献   
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