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61.
Concentrations of lindane from adipose tissue i.e. omentum of sheep from homesteads of island Krk that were treated with lindane, were compared with the concentrations of lindane measured in adipose tissue of non treated sheep from husbandry cooperative on island Cres. Evaluation of food safety for this samples were estimated by comparing obtained results and maximum tolerance concentration (MTC) for lindane (2.0 and 0.2 mg/kg). In treated lambs from Krk measured concentrations of lindane were in range from 0.0038 to 1.8644 mg/kg, and in treated sheep from 0.0094 to 1.646 mg/kg. In control group of lambs and sheep concentration of lindane was < or = 0.0051 mg/kg. Estimation of food safety based on the results from this research are discussable, regarding the fact that MTC prescribed before year 2007 was 2.0 mg/kg. When the new law Regulations of MTC for residues of pesticides in food and animal feed (NN 119/07) came into the force prescribed MTC was 0.02 mg/kg. If food safety of sheep meat from Krk would be estimated based on latter, then 73.4% of samples of lamb meat and 80% of sheep meat could be proclaimed unsafe for human consumption. It is encouraging that after completion of using lindane in year 2005, levels of lindane in adipose tissue of lamb from Krk in year 2006 were under the concentration set by new legislate (< 0.02 mg/kg).  相似文献   
62.
Many wildlife populations are declining due to anthropologic and environmental pressures. Indicators can facilitate detection of and reaction to population declines. We tested spatial population pattern variables as indicators for the future fate of capercaillie populations in Slovenia. This population was surveyed from 1979 to 1983, 1998 to 2000, and 2008 to 2011. We tested the following indicators of spatial population patterns: the proportion of occupied leks in the neighbourhood of each lek, the distance to the nth nearest occupied lek, the distance to the centre of the cluster and the distance to the closest neighbouring cluster. The AUC and conditional and marginal R2 were used to evaluate the strength of the indicators. There was a steep decline in the number of leks in the Dinaric Mountains during the period 1980–2010, while the number of leks in the Eastern Slovenian Alps and Julian Alps decreased until 2000 and then stabilized. There was an increase in the distance to the nearest occupied leks over the years, but there were differences in this indicator between the clusters. A combination of the distance to the fourth nearest occupied lek and the occupancy of the first nine leks best predicted the future of a lek, showing that the indicators used in the study can be used to predict the future fate of a lek. Our results can help guide future conservation and management decisions to conserve capercaille populations.  相似文献   
63.
The aim of this study was to be able to reversibly bind histidine-rich proteins to the surface of maghemite magnetic nanoparticles via coordinative bonding using Zn ions as the anchoring points. We showed that in order to adsorb Zn ions on the maghemite, the surface of the latter needs to be modified. As silica is known to strongly adsorb zinc ions, we chose to modify the maghemite nanoparticles with a nanometre-thick silica layer. This layer appeared to be thin enough for the maghemite nanoparticles to preserve their superparamagnetic nature. As a model the histidine-rich protein bovine serum albumin (BSA) was used. The release of the BSA bound to Zn-decorated silica-coated maghemite nanoparticles was analysed using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). We demonstrated that the bonding of the BSA to such modified magnetic nanoparticles is highly reversible and can be controlled by an appropriate change of the external conditions, such as a pH decrease or the presence/supply of other chelating compounds.  相似文献   
64.
Epstein M 《Bioethics》2007,21(1):23-31
This paper explores one of the most politically sensitive and intellectually neglected issues in bioethics--the interface between the history of contemporary end-of-life ethics and the economics of life and death. It suggests that contrary to general belief, economic impulses have increasingly become part of the conditions in which contemporary end-of-life ethics continues to evolve. Although this conclusion does not refute the philosophical justifications provided by the ethics for itself, it may cast new light upon its social role.  相似文献   
65.
This epidemiological study is completed on island Rab, located in North Adriatic Sea. For this study it is important that Adriatic Sea has one of the highest solar radiations in geographical area of Europe. The aim of this epidemiological study is to estimate correlation between incidence of Age-Related Macular Degeneration (AMD) and exposure of sunlight in two different populations on island Rab. In the first group of population of island Rab, agriculturists and fishermen (n = 1300), incidence of AMD was in 18%, but in urban population only 2.5%. It is very interesting that correlation exists between incidence of AMD and exfoliation syndrome. In the group of chronic exposure to sunlight (agriculturists and fishermen) exfoliation syndrome exists in 28%, but in urban population it has never been seen. The age in both populations was 45-65 years. We can conclude that there is a very significant correlation between chronic exposure to sunlight and appearance of AMD.  相似文献   
66.
The sustainable and scalable production of hydrogen through hydrogen evolution reaction (HER) and oxygen through oxygen evolution reaction (OER) in water splitting demands efficient and robust electrocatalysts. Currently, state‐of‐the‐art electrocatalysts of Pt and IrO2/RuO2 exhibit the benchmark catalytic activity toward HER and OER, respectively. However, expanding their practical application is hindered by their exorbitant price and scarcity. Therefore, the development of alternative effective electrocatalysts for water splitting is crucial. In the last few decades, substantial effort has been devoted to the development of alternative HER/OER and water splitting catalysts based on various transition metals (including Fe, Co, Ni, Mo, and atomic Pt) which show promising catalytic activities and durability. In this review, after a brief introduction and basic mechanism of HER/OER, the authors systematically discuss the recent progress in design, synthesis, and application of single atom and cluster‐based HER/OER and water splitting catalysts. Moreover, the crucial factors that can tune the activity of catalysts toward HER/OER and water splitting such as morphology, crystal defects, hybridization of metals with nonmetals, heteroatom doping, alloying, and formation of metals inside graphitic layered materials are discussed. Finally, the existing challenges and future perspectives for improving the performance of electrocatalysts for water splitting are addressed.  相似文献   
67.
Traction force microscopy (TFM) has emerged as a versatile technique for the measurement of single-cell-generated forces. TFM has gained wide use among mechanobiology laboratories, and several variants of the original methodology have been proposed. However, issues related to the experimental setup and, most importantly, data analysis of cell traction datasets may restrain the adoption of TFM by a wider community. In this review, we summarize the state of the art in TFM-related research, with a focus on the analytical methods underlying data analysis. We aim to provide the reader with a friendly compendium underlying the potential of TFM and emphasizing the methodological framework required for a thorough understanding of experimental data. We also compile a list of data analytics tools freely available to the scientific community for the furtherance of knowledge on this powerful technique.  相似文献   
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Dendritic cell (DC)-based immunotherapy is a promising strategy for the elimination of minimal residual disease in patients with acute myeloid leukemia (AML). Particularly, patients with a high risk of relapse who are not eligible for hematopoietic stem cell transplantation could benefit from such a therapeutic approach. Here, we review our extensive studies on the development of a protocol for the generation of DCs with improved immunogenicity and optimized for the use in cell-based immunotherapy. This new generation DC vaccine combines the production of DCs in only 3 days with Toll-like receptor-signaling-induced cell maturation. These mature DCs are then loaded with RNA encoding the leukemia-associated antigens Wilm’s tumor protein 1 and preferentially expressed antigen in melanoma in order to stimulate an AML-specific T-cell-based immune response. In vitro as well as in vivo studies demonstrated the enhanced capacity of these improved DCs for the induction of tumor-specific immune responses. Finally, a proof-of-concept Phase I/II clinical trial is discussed for post-remission AML patients with high risk for disease relapse.  相似文献   
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