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11.
The emerging of Quantum Dots utilization in industrial or medicinal fields involved a potentially increase of these nanoparticles in environment. In this work, the genotoxic (comet assay) and oxidative effects (SOD activity, TBARS) of functionalized‐QDs and cadmium chloride were investigated on Hediste diversicolor and Eisenia fetida coelomocytes. Results demonstrated that functionalized‐QDs (QDNs) and cadmium chloride induced DNA damages through different mechanisms that depended on the nano‐ or ionic nature of Cd. The minimal genotoxic concentrations for H. diversicolor (<0.001ng/g for QDNs and CdCl2) were lower than for E. fetida (between 0.01 and 0.1 ng/g for QDNs, and between 0.001 and 0.01 ng/g for CdCl2). These results showed that H. diversicolor was more sensitive than E. fetida. The two contaminants had a low impact on the oxidative stress markers. © 2014 Wiley Periodicals, Inc. Environ Toxicol 30: 918–926, 2015.  相似文献   
12.
We studied a patient with mild beta-thalassaemia major under treatment with the oral chelator deferiprone (DFP or L1) for about 10 yr (L1 veteran). Due to poor compliance with desferrioxamine, the patient started compassionate use of DFP at an age of 23 yr with a serum ferritin of 5200 microg/L. Monitoring iron overload by SQUID biosusceptometry revealed a dramatic decrease of liver iron concentrations from 4500 to 950 microg/g(liver) within 9.5 yr. A good clinical response to chelation treatment with DFP was observed together with an improvement of liver and cardiac function and a reduction in the hepatitis virus load.  相似文献   
13.
Decellularized matrices are steadily gaining popularity to study the biology of cells and tissues, as they represent a biomimetic environment in which cells can recapitulate certain behaviours that share similarities with those observed in vivo. Basically, biochemistry, microstructure and mechanics of the decellularized matrices are the most valuable properties that differentiate these culturing systems from conventional bidimensional models. Several procedures to decellularize tissues have been proposed so far, with the common aim to preserve the tissue chemical/physical properties of the original tissue. However, these processes are complex, time‐consuming and expensive. In this work, we propose a cost‐effective, easy‐to‐produce decellularized dermal matrix, derived from animal skin. The chemical/physical processes to obtain the matrices proved to not alter matrix structure and did not induce cytotoxicity issues. To test the validity of the decellularized matrices as a model to study the behaviour of tumour cells in vitro, we performed microstructural and mechanical investigations as well as cell proliferation assays. In particular, three different tumour cell lines were used, which proliferated and invaded the matrix with no additional treatments. Decellularized skin scaffold, presented in this work, could be a strong competitor for conventional 3D systems like synthetic porous scaffolds or hydrogels. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
14.
The leukemic population in 63 patients with acute myeloid leukemia (AML) was studied with 15 monoclonal antibodies that detect lineage-related and stage-related antigens on normal hemopoietic cells. Indirect immunofluorescence and fluorescence-activated cell sorting showed that subpopulations of leukemic cells reacted with some or all antibodies, but the percentage of cells reacting with a single antibody varied widely among patients. The composite antigenic phenotype of the various cases, as determined by immunofluorescence assay, did not correlate with the French-American-British morphological classification. Furthermore, some cells in each case failed to express any antigen normally expressed on myelomonocytic precursors from the level of the early CFU-GM to the mature granulocyte or monocyte. In double-fluorescence experiments, the individual cells expressed none, one, or both antigens. These results demonstrate that there is considerable subpopulation heterogeneity in AML. This heterogeneity may considerably limit or complicate the use of monoclonal antibodies for diagnosis, prognosis, and treatment of acute nonlymphocytic leukemia (ANLL).  相似文献   
15.
The S region of the mouse H-2 complex is genetically defined by a series of alleles, or pseudoalleles, which control the level of a serum globulin, Ss, and of its allotypic vairatn, Slp. In contrast with the products of other genes in the complex, no homologue of the Ss protein has been found in other species, except the rat. In the present study, a component in human plasma was identified which cross-reacts with anti-mouse Ss, and which also displays electrophoretic and size similarities to the mouse Ss protein. This component was isolated and characterized immunochemically as the fourth component of human complement (C'4 or beta1E globulin). Several antisera monospecific for human C'4 cross-react with the mouse Ss protein and detect its genetically determined quantitative variations.  相似文献   
16.
Clinical and Experimental Medicine - The aim of the study is to evaluate the prognostic value of early PCSK9 levels in non-intubated septic patients admitted to the emergency department. This...  相似文献   
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18.
Ethylmalonic encephalopathy (EE) is a rare autosomal recessive disorder characterized by early onset encephalopathy, chronic diarrhoea, petechiae, orthostatic acrocyanosis and defective cytochrome c oxidase (COX) in muscle and brain. High levels of lactic, ethylmalonic and methylsuccinic acids are detected in body fluids. EE is caused by mutations in ETHE1, a mitochondrial sulphur dioxygenase. By studying a suitable mouse model, we found that loss of ETHE1 leads to accumulation of sulphide, which is a poison for COX and other enzymatic activities thus accounting for the main features of EE. We report here the first autopsy case of a child with a genetically confirmed diagnosis of EE, and compare the histological, histochemical and immunohistochemical findings with those of the constitutive Ethe1 (-/-) mice. In addition to COX depleted cells, widespread endothelial lesions of arterioles and capillaries of the brain and gastrointestinal tract were the pathologic hallmarks in both organisms. Our findings of diffuse vascular damage of target critical organs are in keeping with the hypothesis that the pathologic effects of ETHE1 deficiency may stem from high levels of circulating hydrogen sulphide rather than the inability of specific organs to detoxify its endogenous production.  相似文献   
19.
Three mechanical heart valves (two bileaflet prostheses and a tilting one) were investigated in a basic hardware setup in order to evaluate with a hydrophone their opening and closing action in time and in amplitude of each beat. The recorded signal was then segmented into the series of cycles xi(t) having a temporal duration equal to the working period imposed on the valve. Two return maps were defined, in order to evaluate the degree of dispersion of the resulting scatter plot: (i) the amplitude map xi(t) versus xi+1(t); (ii) the delay map for the closure of the valve within each beat versus the successive ones. To evaluate the results obtained, two indices were proposed based on both the degree of dispersion and the deviation of the regression line of the resulting scatter plot with respect to the bisector of the map plane. The tilting disc valve showed a lower degree of dispersion, both in the amplitude signal and in the closure time delays, with respect to the other two bileaflet heart valves. The methodology proposed here could be regarded as an alternative non-invasive tool to investigate the dynamic behaviour of prosthetic heart valves, especially in the case of their suspected failure.  相似文献   
20.
Chronic enzootic haematuria (CEH) is a severe syndrome due to prolonged ingestion of toxic principles of bracken fern, such as quercetin and ptaquiloside. Little information is available on chromosomal instability of cattle with access to bracken fern and suffering from CEH. In the present study, 45 cattle, aged from 7 to 12 years and pastured in the south of Italy, were cytogenetically investigated for the first time in search of both chromosomal aberrations (aneuploidy, gaps, chromatid breaks, chromosome breaks and fragments) and sister chromatid exchanges (SCEs). Of these animals, 30 (group 1) had access to bracken fern and showed signs of CEH, and 15 (group 2; control) did not. Percentage of abnormal cells (aneuploidy, chromatid breaks, chromosome breaks and fragments) was higher in animals affected by CEH (34.7%, group 1) than that (24.3%) reached in the control (group 2). The same results were achieved when including gaps. Indeed, the mean number of cells with structural aberrations excluding gaps (chromatid breaks, chromosome breaks and fragments) per cell was higher (P<0.001) in animals affected by CEH (0.16+/-0.36) than that (0.09+/-0.29) found in the control. Chromosome fragility in cells of animals affected by CEH was also confirmed when applying the SCE test: statistically higher levels (P<0.001) of SCEs were observed in animals with CEH (7.35+/-3.59 SCE/cell, group 1) than those in the control (5.40+/-2.68 SCE/cell).  相似文献   
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