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Luisa F. Escobar-Alvarado Mabel Vaca-Mier Raymundo López-Callejas 《International journal of phytoremediation》2018,20(2):184-189
Industrial pollutants such as heavy metals and hydrocarbons in soils represent a serious concern due to their persistence and negative effects on the environment, affecting cellular processes in living organisms and even causing mutations and cancer. The main objectives of this work were to evaluate the efficiency of Opuntia ficus in the phytoremediation of a soil polluted with used motor oil. Two other species, one with different and one with similar characteristics, relatively, were used for comparison purposes: Lolium perenne and Aloe barbadensis. The effect of the plants on lead solubility and bioaccumulation, the biomass production of each specie and the microbial counts and bacterial identification for each experiment was studied. Total petroleum hydrocarbons (TPH) were measured every 5 weeks throughout the 20-week phytoremediation experiment. At the end of the experiment soluble Pb, Pb extracted by the plant species, microbiological counts, total biomass and bacterial species in soil were analyzed. Even though Lolium perenne showed the highest TPH removal (47%), Opuntia ficus produced the highest biomass and similar removal (46%). Since Opuntia ficus requires low amounts of water and grows fast, it would be a suitable option in the remediation of soils polluted with hydrocarbons and/or heavy metals. 相似文献
165.
Melisa Gómez-Garrido José Mora Navarro Francisco J. Murcia Navarro Ángel Faz Cano 《International journal of phytoremediation》2018,20(10):1033-1042
Phytoextraction is a green technique for the removal of soil contaminants by plants uptake with the subsequent elimination of the generated biomass. The halophytic plant Suaeda vera Forssk. ex J.F.Gmel. is an native Mediterranean species able to tolerate and accumulate salts and heavy metals in their tissues. The objective of this study was to explore the potential use of S. vera for soil metal phytoextraction and to assess the impact of different chelating agents such as natural organic acids (oxalic acid [OA], citric acid [CA]), amino acids (AA) and Pseudomonas fluorescens bacteria (PFB) on the metal uptake and translocation. After 12 months, the highest accumulation of Cu was observed in the root/stem of PFB plots (17.62/8.19 mg/kg), in the root/stem of CA plots for Zn (31.16/23.52 mg/kg) and in the root of OA plots for Cr (10.53 mg/kg). The highest accumulation of metals occurred in the roots (27.33–50.76 mg/kg). Zn was the metal that accumulated at the highest rates in most cases. The phytoextraction percentages were higher for Cu and Zn (~2%) with respect to Cr (~1%). The percentages of metal removal from soil indicate the need to monitor soil properties, to recognize the influence of each treatment and to increase the concentration of bioavailable metals by the use of agricultural management practices aimed at promoting plant growth. 相似文献
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Rafael Bielza Galindo Jesús Llorente Gutiérrez José Luis Pérez González Asunción Mora Casado David Blanco Díaz Javier Escalera Alonso Adoración Morales Fernández Cristina Molano Ortiz Beredys Esmirla García López Nazaret del Amo del Arco Juan Pablo Barro Ordovas Estefanía Arias Muñana Marta Neira Álvarez David Sanz Rosa Jorge Fco. Gómez Cerezo 《Revista espa?ola de geriatría y gerontología》2018,53(1):38-44
Introduction
There are no previous studies evaluating the effect of intravenous iron therapy on functional and cognitive status of patients with hip fracture (HF).Material and methods
A single-centre randomised, placebo-controlled, double-blind and parallel treatment, clinical trial has been designed to assess the efficacy of intravenous iron therapy during the peri-operative period in elderly patients suffering from a HF. Blinding will be ensured by the packaging of the drug infusion system. On days 1, 3, and 5 from admission, the intervention group will receive 200 mg Venofer® (iron sucrose) diluted in 100 ml saline, and the control group 100 ml saline, also on days 1, 3 and 5. Patients will received conventional treatment in ortho-geriatric unit of the Hospital Infanta Sofia. Functional variables (activities of daily living and walking), cognitive (cognitive status and delirium), surgical, demographic and clinical characteristics will be collected during admission in order to assess the impact of treatment. A safety analysis of the treatment will also performed. Patients will be followed-up at 3, 6, and 12 months.Results
The study will attempt to provide evidence on the impact of the intravenous iron administration on functional recovery. It will be determined whether iron therapy negatively affects the incidence of post-operative delirium. Finally, report will be presented on the safety data of intravenous iron in elderly HF patients, as well as the impact on allogenic blood transfusion savings.Conclusions
The inclusion of elderly HF patients admitted to an ortho-geriatric unit, in a clinical trial, will help to improve the knowledge of the treatment impact on a usual scenario, and provide useful data for use in other units. 相似文献168.
Projects funded by International Development Research Centre (IDRC) of Canada and the European Commission have enabled the
examination of more than 3000 samples of maize collected from all regions of Costa Rica at different stages, from the growing
crop through storage to final sale, and at different water contents. Contamination with Aspergillus flavus was frequent and
about 80% of samples contained more than 20 ng aflatoxins g-1 grain. Average contamination with aflatoxins in the Brunca Region
was > 274 ng g -1 while that in other regions was < 70 ng g -1. Except in Brunca region, where it averaged 376 ng g -1, contamination
of grain from commercial sources was slightly less than of that from farms (≤15 ng g-1). It appeared that samples kept on
the cob after harvest contained almost no aflatoxin while shelled samples were frequently highly contaminated. Experiments
were therefore done in Brunca and Huetar Atlantic Regions, utilising 34 experimental maize crops to study in detail the development
of A. flavus and aflatoxin from before harvest, through postharvest treatment before drying and through storage for six months.
A. flavus was isolated more frequently from maize shelled immediately after harvest than from that kept on the cob until it
could be dried, and from more samples from the Brunca Region than from the Huetar Atlantic Region. Samples harvested with
≥18% water content often contained >70% of grains infected with A. flavus but sometimes there were few grains infected. As
found in the initial survey, more aflatoxin contamination developed in shelled maize than in that handled on the cob during
the period from harvesting to drying, especially if the delay was more than 5 days, and more in Brunca than in Huetar. Shelled
grain contained 400–800 ng aflatoxin g -1 in Brunca but <100 ng g-1 in Huetar while grain kept on the cob contained <30 ng
g-1, even with >18% water content. Incidence of Fusarium spp. exceeded 50% except where A. flavus colonized more than 80%
of grains.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
169.
Jesús E. Blanco Miguel Blanco Jorge Blanco Azucena Mora Luis Balaguer Luis Cuervo Carlos Balsalobre Francisco Muoa 《Microbiology and immunology》1997,41(2):77-82
A field study was carried out with the objective of investigating the prevalence of enteropathogenic Escherichia coli (EPEC) with the eae gene in diarrhoeic rabbits. EPEC eae+ were isolated from 60 (74%) of 81 diarrhoeic rabbits sampled in 30 industrial fattening farms localized in the four provinces of Galicia (northwestern Spain). Attaching and effacing lesions were found in 44 of 50 animals processed for histology. The 111 E. coli strains identified belonged to 19 different O serogroups and 13 biotypes. However, 53 (48%) of the strains belonged to serogroup O103 and 36 (32%) showed the serobiotype O103:B14. The eae gene was significantly more frequent (100%; 47 of 47) among the highly pathogenic rhamnose-negative strains of serobiotypes O103:B6 and O103:B14 than among the E. coli strains belonging to other serobiotypes (36%; 23 of 64) (P < 0.001). In this first report about the prevalence of EPEC with the eae gene in rabbits, we conclude that the class of E. coli strains observed is a common cause of diarrhoea in Galician rabbit farms, and that highly pathogenic rhamnose-negative strains of serotype O103:K-:H2 and biotype B14 are specially predominant. 相似文献
170.
Microbial footprints of Pseudomonas aeruginosa MDC attached for 1 h to clean or silanized glass were analyzed with fluorescently labeled lectin probes. Footprint composition varied, depending on cell physiology and substratum surface chemistry. This suggests that substratum physicochemistry affected the structure of cell surfaces of adsorbed organisms. 相似文献