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51.
Marcel Prothmann Florian von Knobelsdorff-Brenkenhoff Agnieszka T?pper Matthias A. Dieringer Etham Shahid Andreas Graessl Jan Rieger Darius Lysiak C. Thalhammer Till Huelnhagen Peter Kellman Thoralf Niendorf Jeanette Schulz-Menger 《PloS one》2016,11(2)
Background
Cardiovascular Magnetic Resonance (CMR) provides valuable information in patients with hypertrophic cardiomyopathy (HCM) based on myocardial tissue differentiation and the detection of small morphological details. CMR at 7.0T improves spatial resolution versus today’s clinical protocols. This capability is as yet untapped in HCM patients. We aimed to examine the feasibility of CMR at 7.0T in HCM patients and to demonstrate its capability for the visualization of subtle morphological details.Methods
We screened 131 patients with HCM. 13 patients (9 males, 56 ±31 years) and 13 healthy age- and gender-matched subjects (9 males, 55 ±31years) underwent CMR at 7.0T and 3.0T (Siemens, Erlangen, Germany). For the assessment of cardiac function and morphology, 2D CINE imaging was performed (voxel size at 7.0T: (1.4x1.4x2.5) mm3 and (1.4x1.4x4.0) mm3; at 3.0T: (1.8x1.8x6.0) mm3). Late gadolinium enhancement (LGE) was performed at 3.0T for detection of fibrosis.Results
All scans were successful and evaluable. At 3.0T, quantification of the left ventricle (LV) showed similar results in short axis view vs. the biplane approach (LVEDV, LVESV, LVMASS, LVEF) (p = 0.286; p = 0.534; p = 0.155; p = 0.131). The LV-parameters obtained at 7.0T where in accordance with the 3.0T data (pLVEDV = 0.110; pLVESV = 0.091; pLVMASS = 0.131; pLVEF = 0.182). LGE was detectable in 12/13 (92%) of the HCM patients. High spatial resolution CINE imaging at 7.0T revealed hyperintense regions, identifying myocardial crypts in 7/13 (54%) of the HCM patients. All crypts were located in the LGE-positive regions. The crypts were not detectable at 3.0T using a clinical protocol.Conclusions
CMR at 7.0T is feasible in patients with HCM. High spatial resolution gradient echo 2D CINE imaging at 7.0T allowed the detection of subtle morphological details in regions of extended hypertrophy and LGE. 相似文献52.
The structures of two new aliphatic acids, isomuronic and neuropogolic acid, from the lichen Neuropogon trachycarpus, were established by spectroscopic (MS, 1H and 13C NMR) and chemical evidence. Circular dichroism data allowed the configuration of isomuronic acid to be assigned as 2R. 相似文献
53.
Sawomir Marek Dominik Tomaszewski Roma ytkowiak Anna Jasiska Marcin Zadworny Krystyna Boratyska Monika Dering Darius Danusevi
ius Jacek Oleksyn Tomasz P. Wyka 《Plant, cell & environment》2022,45(1):121-132
The commonly observed negative relationship between stomatal density (SD) and atmospheric CO2 has led to SD being proposed as an indicator of atmospheric CO2 concentration. The use of SD as a proxy for CO2, however, has been hampered by an insufficient understanding of the intraspecific variation of this trait. We hypothesized that SD in Pinus sylvestris, a widely distributed conifer, varies geographically and that this variation is determined by major climatic variables. By sampling needles from naturally growing trees along a latitudinal range of 32.25°, equivalent to 13.7°C gradient of mean annual temperature (MAT) across Europe, we found that SD decreased from the warmest southern sites to the coldest sites in the north at a rate of 4 stomata per mm2 for each 1°C, with MAT explaining 44% of the variation. Additionally, samples from a provenance trial exhibited a positive relationship between SD and the MAT of the original localities, suggesting that high SD is an adaptation to warm temperature. Our study revealed one of the strongest intraspecific relationships between SD and climate in any woody species, supporting the utility of SD as a temperature, rather than direct CO2, proxy. In addition, our results predict the response of SD to climate warming. 相似文献
54.
Zebra mussel filtration rates and regulating factors have been addressed earlier in a number of studies. Still, only a few
of them have taken into consideration the refiltration phenomenon, and therefore the direct extrapolation of experimental
results may only give the potential filtering capacity, and hence, over- or underestimate the actual amount of seston being
removed by zebra mussels in an ecosystem. The current experimental study aimed to gain insight into the refiltration effect
on the clearance rate of the zebra mussels at relatively high seston concentrations, and its potential role in controlling
the filtration efficiency of the zebra mussel population. The experiment was conducted in a laboratory flume following the
Latin squares design with one fixed (mussel density) and three random factors (initial total particulate matter (TPM) concentration,
flume “wall effect” and distance from the flume inflow area) considered. The results showed the significant effects of mussel
density and the TPM concentration on the effective clearance rate (ECR) of zebra mussels. The higher ECR values were obtained
at denser mussel clumps and lower TPM concentrations. The flume “wall effect” had no significant effect on the ECR, whereas
the distance from the flume inflow area appeared to have a significant impact. A positive relationship between ECR and the
zebra mussel density was most evident in the proximity of the TPM source. Based on the results, we assume that at high TPM
concentration, refiltration may assert itself by the elevated net clearance rate of mussels within dense clumps compared to
that of mussels at relatively low individual densities. This should be taken into consideration while modelling and assessing
the role of the zebra mussel in energy flow and redistribution of organic matter in an ecosystem. 相似文献
55.
Suryo Rahmanto Y Kalinowski DS Lane DJ Lok HC Richardson V Richardson DR 《The Journal of biological chemistry》2012,287(10):6960-6968
Nitrogen monoxide (NO) markedly affects intracellular iron metabolism, and recent studies have shown that molecules traditionally involved in drug resistance, namely GST and MRP1 (multidrug resistance-associated protein 1), are critical molecular players in this process. This is mediated by interaction of these proteins with dinitrosyl-dithiol-iron complexes (Watts, R. N., Hawkins, C., Ponka, P., and Richardson, D. R. (2006) Proc. Natl. Acad. Sci. U.S.A. 103, 7670-7675; Lok, H. C., Suryo Rahmanto, Y., Hawkins, C. L., Kalinowski, D. S., Morrow, C. S., Townsend, A. J., Ponka, P., and Richardson, D. R. (2012) J. Biol. Chem. 287, 607-618). These complexes are bioavailable, have a markedly longer half-life compared with free NO, and form in cells after an interaction between iron, NO, and glutathione. The generation of dinitrosyl-dithiol-iron complexes acts as a common currency for NO transport and storage by MRP1 and GST P1-1, respectively. Understanding the biological trafficking mechanisms involved in the metabolism of NO is vital for elucidating its many roles in cellular signaling and cytotoxicity and for development of new therapeutic targets. 相似文献
56.
57.
Anastasija?ZaikoEmail author Darius?Daunys Sergej?Olenin 《Helgoland Marine Research》2009,63(1):85-94
Habitat engineering role of the invasive zebra mussel Dreissena polymorpha (Pallas) was studied in the Curonian lagoon, a shallow water body in the SE Baltic. Impacts of live zebra mussel clumps and
its shell deposits on benthic biodiversity were differentiated and referred to unmodified (bare) sediments. Zebra mussel bed
was distinguished from other habitat types by higher benthic invertebrate biomass, abundance, and species richness. The impact
of live mussels on biodiversity was more pronounced than the effect of shell deposits. The structure of macrofaunal community
in the habitats with >103 g/m2 of shell deposits devoid of live mussels was similar to that found within the zebra mussel bed. There was a continuous shift
in species composition and abundance along the gradient ‘bare sediments—shell deposits—zebra mussel bed’. The engineering
impact of zebra mussel on the benthic community became apparent both in individual patches and landscape-level analyses. 相似文献
58.
59.