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151.
Golaszewski SM Siedentopf CM Koppelstaetter F Fend M Ischebeck A Gonzalez-Felipe V Haala I Struhal W Mottaghy FM Gallasch E Felber SR Gerstenbrand F 《NeuroImage》2006,29(3):923-929
The purpose of this study was to investigate the sensorimotor cortex response to plantar vibrotactile stimulation using a newly developed MRI compatible vibration device. Ten healthy subjects (20-45 years) were investigated. Vibrotactile stimulation of the sole of the foot with a frequency of 50 Hz and a displacement of 1 mm was performed during fMRI (echo-planar imaging sequence at 1.5 T) using an MRI compatible moving magnet actuator that is able to produce vibration frequencies between 0 and 100 Hz and displacement amplitudes between 0 and 4 mm. The fMRI measurement during vibrotactile stimulation of the right foot revealed brain activation contralaterally within the primary sensorimotor cortex, bilaterally within the secondary somatosensory cortex, bilaterally within the superior temporal, inferior parietal, and posterior insular region, bilaterally within the anterior and posterior cingular gyrus, bilaterally within the thalamus and caudate nucleus, contralaterally within the lentiform nucleus, and bilaterally within the anterior and posterior cerebellar lobe. The advantages of the new MRI compatible vibration device include effective transmission of the stimulus and controlled vibration amplitudes, frequencies, and intensities. The results indicate that plantar vibration can be a suitable paradigm to observe activation within the sensorimotor network in fMRI. Furthermore, the method may be used to determine the optimal responsiveness of the individual sensorimotor network. 相似文献
152.
Burkhard Vangerow Dietrich Häfner Horst Rueckoldt Gernot Marx Nils Ott Martin Leuwer Ilka Frerking Paul G. Germann 《Intensive care medicine》2001,27(9):1526-1531
OBJECTIVE: To assess the effects of C1 inhibitor (INH) administration and r-SP-C surfactant application on oxygenation and lung histology in an acute respiratory distress syndrome model. DESIGN AND SETTING: Randomized, controlled experimental study in an animal research laboratory. Material: 36 adult male Sprague-Dawley rats. INTERVENTIONS: Animals were subjected to repetitive lung lavage. Four experimental groups and two control groups were studied: groups 1 and 2 served as controls. Animals of groups 3-6 received 200 U/kg body weight C1-INH (group 3), 25 mg/kg r-SP-C surfactant (group 4) or both (group 5) at 60 min postlavage (pl). Animals of group 6 were treated with 200 U/kg C1-INH1 at 10 min pl. Animals of group 1 were killed 60 min (min) pl, animals of groups 2-6 were killed at 210 min pl. Thereafter the lungs were excised for histological examination. MEASUREMENTS AND RESULTS: Hyaline membrane formation, intra-alveolar neutrophil (PMN) accumulation and intra-alveolar/perivascular haemorrhage were graded semiquantitatively (0-4). Blood gases were determined 120, 150, 180 and 210 min pl. At 210 min pl pO(2) in group 4 (456+/-74 mmHg) and group 5 (387+/-155 mmHg) was significantly higher than in controls (72+/-29 mmHg) or after C1-INH monotherapy (group 3: 120+/-103, group 6: 63+/-12 mmHg). PMN infiltration after C1-INH monotherapy was significantly less severe than in controls. The combination of r-SP-C surfactant and C1-INH led to significantly lower PMN infiltration than surfactant monotherapy. CONCLUSION: In this lavage-induced acute respiratory distress syndrome model the administration of C1-INH might be followed by a higher clinical efficacy of exogenously supplied recombinant SP-C surfactant. 相似文献
153.
154.
裸大鼠人结肠癌细胞肝转移模型的建立 总被引:3,自引:0,他引:3
沈岩 《中华实验外科杂志》1999,16(3):272-272
为评价涉及肝、血管等外科操作的肝转移治疗模式,我们成功地在个体较大的裸大鼠体内建立了人结肠癌(HCC)细胞肝转移模型,并可利用该模型筛选高转移性细胞系,现报道如下:一、材料与方法SPF条件饲养、鼠龄4周的雄性Rowett棵大鼠(Hsd:RH-un/un)38只用于本实验。人结肠中分化腺癌细胞系WIDr、HT-29及HT-29的2个亚系HT-29。和HT-29b(分别通过体外组织培养从母代HT-29和HT-29a的棵大鼠肝转移灶获得)培养于含体积分数为Ic%胎牛血清、100U/ml青霉素、10oms/L链霉素和L一谷氨酸胺dJRP-Mll640中,在37C、体积分… 相似文献
155.
156.
Maria Alenita Oliveira Ana Luisa Godoy Fernandes Lucia Ande Santos Maria Amélia Dos Santos Carvalho Sonia Maria Faresin Ilka Lopes Santoro 《The Journal of asthma》2007,44(5):407-410
Aim. To study any discriminative properties of SF-36 and QQL-EPM in stable and non-controlled moderate asthmatic patients. Methods. A total of 63 asthmatic patients were assessed regarding asthma symptoms, FEV1 % predicted value, PEF, ED visits and hospitalizations, QQL-EPM and SF-36 questionnaires. Results. QQL-EPM highlighted significance in all domains to distinguish stable from non-controlled patients (p = 0.0001) while SF-36 was only significant in 3 of its 7 domains (p = 0.009). Conclusion. The study showed that the specific quality of life questionnaire for asthma (QQL-EPM) demonstrates better discriminative properties that characterize asthma control when compared with the more generic SF-36 questionnaire. 相似文献
157.
158.
Oehlmann J Schulte-Oehlmann U Bachmann J Oetken M Lutz I Kloas W Ternes TA 《Environmental health perspectives》2006,114(Z1):127-133
Previous investigations have shown that bisphenol A (BPA) induces a superfeminization syndrome in the freshwater snail Marisa cornuarietis at concentrations as low as 1 microg/L. Superfemales are characterized by the formation of additional female organs, enlarged accessory sex glands, gross malformations of the pallial oviduct, and a stimulation of egg and clutch production, resulting in increased female mortality. However, these studies were challenged on the basis of incomplete experimentation. Therefore, the objective of the current approach was to bridge several gaps in knowledge by conducting additional experiments. In an initial series of experiments, study results from the reproductive phase of the snails were evaluated in the sub-micrograms per liter range. Before and after the spawning season, superfemale responses were observed [NOEC (no observed effect concentration) 7.9 ng/L, EC10 (effective concentration at 10%) 13.9 ng/L], which were absent during the spawning season. A further experiment investigated the temperature dependence of BPA responses by exposing snails at two temperatures in parallel. The adverse effect of BPA was at least partially masked at 27 degrees C (EC10 998 ng/L) when compared with 20 degrees C (EC10 14.8 ng/L). In M. cornuarietis, BPA acts as an estrogen receptor (ER) agonist, because effects were completely antagonized by a co-exposure to tamoxifen and Faslodex. Antiandrogenic effects of BPA, such as a significant decrease in penis length at 20 degrees C, were also observed. Competitive receptor displacement experiments indicate the presence of androgen- and estrogen-specific binding sites. The affinity for BPA of the estrogen binding sites in M. cornuarietis is higher than that of the ER in aquatic vertebrates. The results emphasize that prosobranchs are affected by BPA at lower concentrations than are other wildlife groups, and the findings also highlight the importance of exposure conditions. 相似文献
159.
Frerking I Sengler C Günther A Walmrath HD Stevens P Witt H Landt O Pison U Nickel R 《Critical care medicine》2005,33(10):2404-2406
OBJECTIVE: Different risk factors are presumably involved in the pathogenesis of acute respiratory distress syndrome (ARDS) including genetic factors. Clara cell protein 16 (CC16) is a potential candidate gene for ARDS susceptibility because reduced levels of the anti-inflammatory CC16 have been observed in bronchoalveolar lavage fluids or serum of patients with different inflammatory lung diseases. Furthermore, CC16 potently inhibits phospholipase A2, which plays a major role in ARDS pathophysiology. A functional polymorphism (-26G>A) was previously identified and related to decreased CC16 levels, asthma, and asthma severity. DESIGN: Observational study. SETTINGS: Adults with ARDS were recruited from intensive care units in two university medical centers. SUBJECTS: We evaluated the role of this genetic variant in 117 German patients with ARDS and 373 German controls. MEASUREMENTS: The CC16 -26G>A polymorphism was analyzed by melting-curve analysis using a pair of fluorescence resonance energy transfer probes. MAIN RESULTS: CC16 genotype frequencies in ARDS patients did not differ from those seen in controls. Also, the allele frequencies were identical in patients compared with controls (0.66 and 0.34). Moreover, only one of the patients who died (n = 27) was homozygous for the -26A allele. CONCLUSIONS: The CC16 -26G>A polymorphism does not affect the susceptibility to and the outcome of ARDS. 相似文献
160.
Steinberg CE Höss S Kloas W Lutz I Meinelt T Pflugmacher S Wiegand C 《Environmental toxicology》2004,19(4):409-411
Humic substances comprise the majority of organic matter in freshwater ecosystems and were thought to be inert or refractory, except for photolytic degradation. However, evidence is increasing that humic substances interact with aquatic organisms similarly to weak anthropogenic chemicals with nonspecific and specific effects. One specific effect is a hormonelike effect, namely, modulation of the number of offspring, which was first described with the nematode Caenorhabditis elegans. Yet a hormonelike effect is not restricted to only the nematode. With the ornamental swordtail fish, Xiphophorus helleri, and the South African clawed frog, Xenopus laevis, we present phenomenological evidence that slight feminization occurred when these vertebrate species were exposed to a synthetic humic substance, a condensation product of polyphenols. The slight feminization was dose dependent. 相似文献