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991.
Katarzyna Bociąg Emilia Rekowska Krzysztof Banaś 《Oceanological and hydrobiological studies.》2011,40(2):30-36
The subject of this work is a comparative analysis of stonewort populations in 5 lobelia lakes of the Kashubian Lakeland based on literature data from the mid-1970s and the authors’ own studies from 2006. In the 1970s 15 sites of 7 stonewort species: Chara delicatula, C. fragilis, C. tomentosa, C. rudis, Nitella flexilis, N. opaca and N. mucronata were recorded in the lakes under study. The populations of C. delicatula and N. flexilis occupied the area from 0.3 to 6 m deep and were characterized by 20% cover on average. Thirty years later, in 2006, the presence of only 6 out of 15 stands was confirmed: 3 of C. delicatula and 3 of N. flexilis. Thus, a total of 9 stands (60%) and 5 species (71%) had disappeared completely. The majority of the preserved populations survived in a vestigial form. Population areas of C. delicatula reached a depth of 2 m and their cover did not exceed 5%. Populations of N. flexilis occupied the littoral up to a depth of 7 m and had 10% cover. The disappearance of stoneworts was probably caused by both anthropogenic factors and natural processes. 相似文献
992.
993.
Support provided by nurses to parents of hospitalized children – cultural adaptation and validation of Nurse Parent Support Tool and initial research results
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994.
This article summarizes a process which exemplifies the potential impact of municipal investment on the burden of cardiovascular disease (CVD) in city populations. We report on Developing an evidence-based approach to city public health planning and investment in Europe (DECiPHEr), a project part funded by the European Union. It had twin objectives: first, to develop and validate a vocational educational training package for policy makers and political decision takers; second, to use this opportunity to iterate a robust and user-friendly investment tool for maximizing the public health impact of ‘mainstream’ municipal policies, programs and investments. There were seven stages in the development process shared by an academic team from Sheffield Hallam University and partners from four cities drawn from the WHO European Healthy Cities Network. There were five iterations of the model resulting from this process. The initial focus was CVD as the biggest cause of death and disability in Europe. Our original prototype ‘cost offset’ model was confined to proximal determinants of CVD, utilizing modified ‘Framingham’ equations to estimate the impact of population level cardiovascular risk factor reduction on future demand for acute hospital admissions. The DECiPHEr iterations first extended the scope of the model to distal determinants and then focused progressively on practical interventions. Six key domains of local influence on population health were introduced into the model by the development process: education, housing, environment, public health, economy and security. Deploying a realist synthesis methodology, the model then connected distal with proximal determinants of CVD. Existing scientific evidence and cities’ experiential knowledge were ‘plugged-in’ or ‘triangulated’ to elaborate the causal pathways from domain interventions to public health impacts. A key product is an enhanced version of the cost offset model, named Sheffield Health Effectiveness Framework Tool, incorporating both proximal and distal determinants in estimating the cost benefits of domain interventions. A key message is that the insights of the policy community are essential in developing and then utilising such a predictive tool. 相似文献
995.
Anna Lenart Katarzyna Wolny-Koładka 《Bulletin of environmental contamination and toxicology》2013,90(1):85-90
The present study aimed to identify the effect of heavy metal concentration and soil pH on the abundance of the selected soil microorganisms within ArcelorMittal Poland steelworks, Cracow. The analysis included 20 soil samples, where the concentration of Fe, Zn, Cd, Pb, Ni, Cu, Mn, Cr and soil pH were evaluated together with the number of mesophilic bacteria, fungi, Actinomycetes and Azotobacter spp. In the majority of samples soil pH was alkaline. The limits of heavy metals exceeded in eight samples and in one sample, the concentration of Zn exceeded 31-fold. Chromium was the element which most significantly limited the number of bacteria and Actinomycetes. 相似文献
996.
Kamil Goc Janusz Przewo
nik Katarzyna Witulska Leszek Chlubny Waldemar Tokarz Tomasz Strczek Jan Marek Michalik Jakub Jurczyk Ivo Utke Jerzy Lis Czesaw Kapusta 《Materials》2021,14(12)
A study of Ti3Al1−xSixC2 (x = 0 to x = 1) MAX-phase alloys is reported. The materials were obtained from mixtures of Ti3AlC2 and Ti3SiC2 powders with hot pressing sintering technique. They were characterised with X-ray diffraction, heat capacity, electrical resistivity, and magnetoresistance measurements. The results show a good quality crystal structure and metallic properties with high residual resistivity. The resistivity weakly varies with Si doping and shows a small, positive magnetoresistance effect. The magnetoresistance exhibits a quadratic dependence on the magnetic field, which indicates a dominant contribution from open electronic orbits. The Debye temperatures and Sommerfeld coefficient values derived from specific heat data show slight variations with Si content, with decreasing tendency for the former and an increase for the latter. Experimental results were supported by band structure calculations whose results are consistent with the experiment concerning specific heat, resistivity, and magnetoresistance measurements. In particular, they reveal that of the s-electrons at the Fermi level, those of Al and Si have prevailing density of states and, thus predominantly contribute to the metallic conductivity. This also shows that the high residual resistivity of the materials studied is an intrinsic effect, not due to defects of the crystal structure. 相似文献
997.
Bethalihem Teferi Samuel Marcin Barburski Jaroslaw R Blaszczak Ewa Witczak Katarzyna Abramczyk 《Materials》2021,14(11)
Utilizing textile-based acoustic materials can be considered basically from two points of view. First, it may be used as a sound absorbing material. Second, it may be used as a decoration that gives the surrounding area a new artistic appearance. To improve the acoustic possibilities of any woven fabric, it is necessary to study the influences of yarn characteristics and the internal structures of weave interlacement. To understand the impact of the yarn on the fabric, the samples were prepared using only polyester fiber as textured, twisted, and staple yarns. Regarding this experiment, the basic weave’s structure type, such as plain, rib, sateen, and twill, were used. Overall, 16 woven fabrics were prepared. The investigation was performed in the range of low to medium acoustic frequencies. The experiments were conducted in an anechoic chamber. Compared to other yarn types, fabrics formed from textured polyester yarn had higher sound absorption properties. Moreover, the observed results show that the different incidence angles of acoustic signals influence the measured sound absorption properties of a textile. 相似文献
998.
999.
1000.
Katarzyna Mizia-Stec Maciej Haberka PhD Magdalena Mizia PhD Artur Chmiel PhD Joanna Wierzbicka-Chmiel PhD Mariusz Skowerski PhD Zbigniew Gasior 《Journal of nuclear cardiology》2008,15(5):655-662
Background. Regardless of normal coronary angiograms, coronary artery calcium (CAC) can be found in cardiac syndrome X (CSX) patients.
According to some data, a relationship between the CAC score and markers of early atherosclerosis in CSX has been observed.
Our aim was to assess whether the extent of the CAC score assessed by multislice computed tomography (MSCT) with a 64-slice
system in CSX patients is related to brachial artery reactivity, intima-media thickness (IMT), and arterial compliance indexes.
Methods and Results. High-resolution ultrasound was used to measure flow-mediated dilatation (FMD) and nitroglycerin-mediated vasodilatation,
as well as the following parameters of arterial structural changes: IMT, pulse wave velocity, total arterial compliance, and
stiffness index. MSCT was used to assess the presence and the quantity of CAC. The study group consisted of 46 CSX patients
(mean age, 56.3±9 years), whereas the control group comprised 21 healthy subjects (mean age, 54.9±7 years). The assessment
of the vascular parameters showed significantly decreased FMD and increased IMT in the CSX subjects (9.06%±3.2% and 0.67±0.1
mm, respectively) in comparison to the control subjects (17.42%±8.4% [P=.008] and 0.57 ± 0.2 mm [P=.021], respectively). CAC was detectable in 19 CSX patients (41%) (CAC range according to Agatston score, 2–500; mean, 101.6;
median, 26.5) and in 1 control subject (4.8%) (CAC value, 13). CSX patients with detectable CAC were characterized by a significantly
higher age (P=.001), lower body mass index (P=.017), and increased stiffness index (P=.020); there were no differences in FMD and IMT values. In a multivariate logistic and linear regression analysis, age was
the only risk factor independently associated with the presence of CAC (P=.001) and the log(CAC+1) value (P=.01). In the subgroup of women, log(CAC+1) significantly correlated with age (r=0.587, P=.002) and stiffness index (r=0.427, P=.024), and in a borderline significant manner, it correlated with weight (r=−0.329, P=.07) and waist-hip ratio (r=0.315, P=.07). There were no significant correlations in the male subgroup.
Conclusions. Low ranges of CAC are frequently detectable in CSX patients, and the results are age-related and independent of impaired
early indexes of functional and structural vascular remodeling. 相似文献