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111.
Rafael Gregorio Mendes Britta Koch Alicja Bachmatiuk Ahmed Aboud El-Gendy Yulia Krupskaya Armin Springer Rüdiger Klingeler Oliver Schmidt Bernd Büchner Samuel Sanchez Mark Hermann Rümmeli 《Biochimica et Biophysica Acta (BBA)/General Subjects》2014
Background
Iron oxide nanoparticles hold great promise for future biomedical applications. To this end numerous studies on iron oxide nanoparticles have been conducted. One aspect these studies reveal is that nanoparticle size and shape can trigger different cellular responses through endocytic pathways, cell viability and early apoptosis. However, systematic studies investigating the size dependence of iron oxide nanoparticles with highly defined diameters across multiple cells lines are not available yet.Methods
Iron oxide nanoparticles with well-defined size distributions were prepared. All samples were thoroughly characterized and the cytotoxicity for four standard cell lines (HeLa Kyoto, human osteosarcoma (U2OS), mouse fibroblasts (NIH 3T3) and mouse macrophages (J7442)) where investigated.Results
Our findings show that small differences in size distribution (ca. 10 nm) of iron oxide nanoparticles do not influence cytotoxicity, while uptake is size dependent. Cytotoxicity is dose-dependent. Broad distributions of nanoparticles are more easily internalized as compared to the narrow distributions for two of the cell lines tested (HeLa Kyoto and mouse macrophages (J7442)).Conclusion
The data indicate that it is not feasible to probe changes in cytotoxicity within a small size range (10 nm). However, TEM investigations of the nanoparticles indicate that cellular uptake is size dependent.General significance
The present work compares narrow and broad distributions for various samples of carbon-coated iron oxide nanoparticles. The data highlights that cells differentiate between nanoparticle sizes as indicated by differences in cellular uptake. This information provides valuable knowledge to better understand the interaction of nanoparticles and cells. 相似文献112.
Seeds of alfalfa (Medicago sativa L.) can exhibit seedcoat imposed dormancy, which produces hard seeds within a seed lot. These seeds do not germinate because they do not imbibe water due to a barrier to water entry in the seed coat. The aim of this work was to analyze the anatomical and chemical characteristics of the testa of alfalfa seeds with respect to water permeability levels. The anatomy of seeds of the cv. Baralfa 85 was studied and structural substances, polyphenols, tannins and cutin present in the testa of seeds of different water permeability levels were determined. The anatomical characteristics of the seed coat and the proportions of components were found to determine the permeability level of the seed coat, an aspect that is associated with the physical seed dormancy level. Anatomically, increased thickness of the testa was associated with a lower permeability level. The difference may be attributed to the variation in cuticle thickness, length of macrosclereids and thickness of the cell wall, and presence and development of osteosclereids. From the physiological and chemical points of view, the mechanism of physical dormancy of the testa is explained by a greater amount of components that repel water and cement the cell wall, such as polyphenols, lignins, condensed tannins, pectic substances, and a lower proportion of cellulose and hemicellulose. 相似文献
113.
Andre M Siqueira Janieldo A Cavalcante Shelia Vítor-Silva Roberto C Reyes-Lecca Aline C Alencar Wuelton M Monteiro Márcia AA Alexandre Mour?o Maria Paula G Caterina Guinovart Quique Bassat Maria das Gra?as C Alecrim Marcus VG Lacerda 《Memórias do Instituto Oswaldo Cruz》2014,109(5):569-576
Anaemia is amongst the major complications of malaria, a major public health problem
in the Amazon Region in Latin America. We examined the haemoglobin (Hb)
concentrations of malaria-infected patients and compared it to that of
malaria-negative febrile patients and afebrile controls. The haematological
parameters of febrile patients who had a thick-blood-smear performed at an infectious
diseases reference centre of the Brazilian Amazon between December 2009-January 2012
were retrieved together with clinical data. An afebrile community control group was
composed from a survey performed in a malaria-endemic area. Hb concentrations and
anaemia prevalence were analysed according to clinical-epidemiological status and
demographic characteristics. In total, 7,831 observations were included. Patients
with Plasmodium falciparum infection had lower mean Hb
concentrations (10.5 g/dL) followed by P. vivax-infected individuals
(12.4 g/dL), community controls (12.8 g/dL) and malaria-negative febrile patients
(13.1 g/dL) (p < 0.001). Age, gender and clinical-epidemiological status were
strong independent predictors for both outcomes. Amongst malaria-infected
individuals, women in the reproductive age had considerably lower Hb concentrations.
In this moderate transmission intensity setting, both vivax and falciparum malaria
are associated with reduced Hb concentrations and risk of anaemia throughout a wide
age range. 相似文献
114.
Khalid A El-Gendy Gary K Atkin Robert E Brightwell Paul Richman Jeremy I Livingstone 《International Seminars in Surgical Oncology : ISSO》2008,5(1):22
Reported is an unusual case of adjacent thoracic lymph nodes demonstrating metastases from two different primary malignancies. A 51 year-old woman with a previous history of bilateral breast cancer underwent a radical gastro-oesophagectomy for adenocarcinoma of the lower third of the oesophagus. The resection specimen demonstrated breast and oesophageal metastases in adjacent thoracic lymph nodes. Mechanisms for this phenomenon, including the known local immune suppression on lymphoid cells by oesophageal carcinoma cells, are discussed. 相似文献
115.
Archives of Microbiology - 相似文献
116.
117.